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src/EspSoftwareSerial/LICENSE

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+That's all there is to it!

src/EspSoftwareSerial/README.md

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+# EspSoftwareSerial
+
+## Implementation of the Arduino software serial library for the ESP8266 / ESP32 family
+
+This fork implements interrupt service routine best practice.
+In the receive interrupt, instead of blocking for whole bytes
+at a time - voiding any near-realtime behavior of the CPU - only level
+change and timestamp are recorded. The more time consuming phase
+detection and byte assembly are done in the main code.
+
+Except at high bitrates, depending on other ongoing activity,
+interrupts in particular, this software serial adapter
+supports full duplex receive and send. At high bitrates (115200bps)
+send bit timing can be improved at the expense of blocking concurrent
+full duplex receives, with the
+`EspSoftwareSerial::UART::enableIntTx(false)` function call.
+
+The same functionality is given as the corresponding AVR library but
+several instances can be active at the same time. Speed up to 115200 baud
+is supported. Besides a constructor compatible to the AVR SoftwareSerial class,
+and updated constructor that takes no arguments exists, instead the `begin()`
+function can handle the pin assignments and logic inversion.
+It also has optional input buffer capacity arguments for byte buffer and ISR bit buffer.
+This way, it is a better drop-in replacement for the hardware serial APIs on the ESP MCUs.
+
+Please note that due to the fact that the ESPs always have other activities
+ongoing, there will be some inexactness in interrupt timings. This may
+lead to inevitable, but few, bit errors when having heavy data traffic
+at high baud rates.
+
+This library supports ESP8266, ESP32, ESP32-S2 and ESP32-C3 devices.
+
+## Resource optimization
+
+The memory footprint can be optimized to just fit the amount of expected
+incoming asynchronous data.
+For this, the `EspSoftwareSerial::UART` constructor provides two arguments. First, the
+octet buffer capacity for assembled received octets can be set. Read calls are
+satisfied from this buffer, freeing it in return.
+Second, the signal edge detection buffer of 32bit fields can be resized.
+One octet may require up to to 10 fields, but fewer may be needed,
+depending on the bit pattern. Any read or write calls check this buffer
+to assemble received octets, thus promoting completed octets to the octet
+buffer, freeing fields in the edge detection buffer.
+
+Look at the swsertest.ino example. There, on reset, ASCII characters ' ' to 'z'
+are sent. This happens not as a block write, but in a single write call per
+character. As the example uses a local loopback wire, every outgoing bit is
+immediately received back. Therefore, any single write call causes up to
+10 fields - depending on the exact bit pattern - to be occupied in the signal
+edge detection buffer. In turn, as explained before, each single write call
+also causes received bit assembly to be performed, promoting these bits from
+the signal edge detection buffer to the octet buffer as soon as possible.
+Explaining by way of contrast, if during a a single write call, perhaps because
+of using block writing, more than a single octet is received, there will be a
+need for more than 10 fields in the signal edge detection buffer.
+The necessary capacity of the octet buffer only depends on the amount of incoming
+data until the next read call.
+
+For the swsertest.ino example, this results in the following optimized
+constructor arguments to spend only the minimum RAM on buffers required:
+
+The octet buffer capacity (`bufCapacity`) is 95 (93 characters net plus two tolerance).
+The signal edge detection buffer capacity (`isrBufCapacity`) is 11, as each
+single octet can have up to 11 bits on the wire,
+which are immediately received during the write, and each
+write call causes the signal edge detection to promote the previously sent and
+received bits to the octet buffer.
+
+In a more generalized scenario, calculate the bits (use message size in octets
+times 10) that may be asynchronously received to determine the value for
+`isrBufCapacity` in the constructor. Also use the number of received octets
+that must be buffered for reading as the value of `bufCapacity`.
+The more frequently your code calls write or read functions, the greater the
+chances are that you can reduce the `isrBufCapacity` footprint without losing data,
+and each time you call read to fetch from the octet buffer, you reduce the
+need for space there.
+
+## EspSoftwareSerial::Config and parity
+The configuration of the data stream is done via a `EspSoftwareSerial::Config`
+argument to `begin()`. Word lengths can be set to between 5 and 8 bits, parity
+can be N(one), O(dd) or E(ven) and 1 or 2 stop bits can be used. The default is
+`SWSERIAL_8N1` using 8 bits, no parity and 1 stop bit but any combination can
+be used, e.g. `SWSERIAL_7E2`. If using EVEN or ODD parity, any parity errors
+can be detected with the `readParity()` and `parityEven()` or `parityOdd()`
+functions respectively. Note that the result of `readParity()` always applies
+to the preceding `read()` or `peek()` call, and is undefined if they report
+no data or an error.
+
+To allow flexible 9-bit and data/addressing protocols, the additional parity
+modes MARK and SPACE are also available. Furthermore, the parity mode can be
+individually set in each call to `write()`.
+
+This allows a simple implementation of protocols where the parity bit is used to
+distinguish between data and addresses/commands ("9-bit" protocols). First set
+up EspSoftwareSerial::UART with parity mode SPACE, e.g. `SWSERIAL_8S1`. This will add a
+parity bit to every byte sent, setting it to logical zero (SPACE parity).
+
+To detect incoming bytes with the parity bit set (MARK parity), use the
+`readParity()` function. To send a byte with the parity bit set, just add
+`MARK` as the second argument when writing, e.g. `write(ch, SWSERIAL_PARITY_MARK)`.
+
+## Checking for correct pin selection / configuration 
+In general, most pins on the ESP8266 and ESP32 devices can be used by EspSoftwareSerial, 
+however each device has a number of pins that have special functions or require careful
+handling to prevent undesirable situations, for example they are connected to the 
+on-board SPI flash memory or they are used to determine boot and programming modes 
+after powerup or brownouts. These pins are not able to be configured by this library.
+
+The exact list for each device can be found in the
+[ESP32 data sheet](https://www.espressif.com/sites/default/files/documentation/esp32_datasheet_en.pdf)
+in sections 2.2 (Pin Descriptions) and 2.4 (Strapping pins). There is a discussion
+dedicated to the use of GPIO12 in this
+[note about GPIO12](https://github.com/espressif/esp-idf/tree/release/v3.2/examples/storage/sd_card#note-about-gpio12).
+Refer to the `isValidPin()`, `isValidRxPin()` and `isValidTxPin()`
+functions in the `EspSoftwareSerial::GpioCapabilities` class for the GPIO restrictions
+enforced by this library by default.
+
+The easiest and safest method is to test the object returned at runtime, to see if 
+it is valid. For example:
+
+```
+#include <SoftwareSerial.h>
+
+#define MYPORT_TX 12
+#define MYPORT_RX 13
+
+EspSoftwareSerial::UART myPort;
+
+[...]
+
+Serial.begin(115200); // Standard hardware serial port
+
+myPort.begin(38400, SWSERIAL_8N1, MYPORT_RX, MYPORT_TX, false);
+if (!myPort) { // If the object did not initialize, then its configuration is invalid
+  Serial.println("Invalid EspSoftwareSerial pin configuration, check config"); 
+  while (1) { // Don't continue with invalid configuration
+    delay (1000);
+  }
+} 
+
+[...]
+```
+
+## Using and updating EspSoftwareSerial in the esp8266com/esp8266 Arduino build environment
+
+EspSoftwareSerial is both part of the BSP download for ESP8266 in Arduino,
+and it is set up as a Git submodule in the esp8266 source tree,
+specifically in `.../esp8266/libraries/SoftwareSerial` when using a Github
+repository clone in your Arduino sketchbook hardware directory.
+This supersedes any version of EspSoftwareSerial installed for instance via
+the Arduino library manager, it is not required to install EspSoftwareSerial
+for the ESP8266 separately at all, but doing so has ill effect.
+
+The responsible maintainer of the esp8266 repository has kindly shared the
+following command line instructions to use, if one wishes to manually
+update EspSoftwareSerial to a newer release than pulled in via the ESP8266 Arduino BSP:
+
+To update esp8266/arduino EspSoftwareSerial submodule to lastest master:
+
+Clean it (optional):
+```shell
+$ rm -rf libraries/SoftwareSerial
+$ git submodule update --init
+```
+Now update it:
+```shell
+$ cd libraries/SoftwareSerial
+$ git checkout master
+$ git pull
+```

src/EspSoftwareSerial/examples/bitpattern/bitpattern.ino

@@ -0,0 +1,71 @@
+#include "SoftwareSerial.h"
+
+#ifndef D5
+#if defined(ESP8266)
+#define D8 (15)
+#define D5 (14)
+#define D7 (13)
+#define D6 (12)
+#define RX (3)
+#define TX (1)
+#elif defined(ESP32)
+#define D8 (5)
+#define D5 (18)
+#define D7 (23)
+#define D6 (19)
+#define RX (3)
+#define TX (1)
+#endif
+#endif
+
+EspSoftwareSerial::UART swSer;
+#ifdef ESP8266
+auto logSer = EspSoftwareSerial::UART(-1, TX);
+auto hwSer = Serial;
+#else
+auto logSer = Serial;
+auto hwSer = Serial1;
+#endif
+
+constexpr uint32_t TESTBPS = 115200;
+
+void setup() {
+	delay(2000);
+#ifdef ESP8266
+	hwSer.begin(TESTBPS, ::SERIAL_8N1);
+	hwSer.swap();
+#else
+	hwSer.begin(TESTBPS, ::SERIAL_8N1, D6, D5);
+#endif
+	logSer.begin(115200);
+	logSer.println(PSTR("\nOne Wire Half Duplex Bitpattern and Datarate Test"));
+	swSer.begin(TESTBPS, EspSoftwareSerial::SWSERIAL_8N1, D6, D5);
+	swSer.enableIntTx(true);
+	logSer.println(PSTR("Tx on swSer"));
+}
+
+uint8_t val = 0xff;
+
+void loop() {
+	swSer.write((uint8_t)0x00);
+	swSer.write(val);
+	swSer.write(val);
+	auto start = ESP.getCycleCount();
+	int rxCnt = 0;
+	while (ESP.getCycleCount() - start < ESP.getCpuFreqMHz() * 1000000 / 10) {
+		if (hwSer.available()) {
+			auto rxVal = hwSer.read();
+			if ((!rxCnt && rxVal) || (rxCnt && rxVal != val)) {
+				logSer.printf(PSTR("Rx bit error: tx = 0x%02x, rx = 0x%02x\n"), val, rxVal);
+			}
+			++rxCnt;
+		}
+	}
+	if (rxCnt != 3) {
+		logSer.printf(PSTR("Rx cnt error, tx = 0x%02x\n"), val);
+	}
+	++val;
+	if (!val) {
+		logSer.println("Starting over");
+	}
+}

src/EspSoftwareSerial/examples/circular_queue_mp_test/mp_queue_test.cpp

@@ -0,0 +1,74 @@
+// circular_mp_test.cpp : This file contains the 'main' function. Program execution begins and ends there.
+//
+
+#include <iostream>
+#include <thread>
+#include <chrono>
+#include <vector>
+#include "circular_queue/circular_queue_mp.h"
+
+struct qitem
+{
+	// produer id
+	int id;
+	// monotonic increasing value
+	int val = 0;
+};
+
+constexpr int TOTALMESSAGESTARGET = 60000000;
+// reserve one thread as consumer
+const auto THREADS = std::thread::hardware_concurrency() / 2 - 1;
+const int MESSAGES = TOTALMESSAGESTARGET / THREADS;
+circular_queue<std::thread> threads(THREADS);
+circular_queue_mp<qitem> queue(threads.capacity()* MESSAGES / 10);
+std::vector<int> checks(threads.capacity());
+
+int main()
+{
+	using namespace std::chrono_literals;
+	std::cerr << "Utilizing " << THREADS << " producer threads" << std::endl;
+	for (int i = 0; i < threads.capacity(); ++i)
+	{
+		threads.push(std::thread([i]() {
+			for (int c = 0; c < MESSAGES;)
+			{
+				// simulate some load
+				auto start = std::chrono::system_clock::now();
+				while (std::chrono::system_clock::now() - start < 1us);
+				if (queue.push({ i, c }))
+				{
+					++c;
+				}
+				else
+				{
+					//std::cerr << "queue full" << std::endl;
+					//std::this_thread::sleep_for(10us);
+				}
+				//if (0 == c % 10000) std::this_thread::sleep_for(10us);
+			}
+			}));
+	}
+	for (int o = 0; o < threads.available() * MESSAGES; ++o)
+	{
+		auto now = std::chrono::system_clock::now();
+		while (!queue.available())
+		{
+			auto starvedFor = std::chrono::system_clock::now() - now;
+			if (starvedFor > 20s) std::cerr << "queue starved for > 20s" << std::endl;
+			//std::this_thread::sleep_for(20ms);
+		}
+		auto item = queue.pop();
+		if (checks[item.id] != item.val)
+		{
+			std::cerr << "item mismatch" << std::endl;
+		}
+		checks[item.id] = item.val + 1;
+		if (0 == item.val % 1000) std::this_thread::sleep_for(100us);
+	}
+	while (threads.available())
+	{
+		auto thread = threads.pop();
+		thread.join();
+	}
+	return 0;
+}

src/EspSoftwareSerial/examples/loopback/loopback.ino

@@ -0,0 +1,279 @@
+#include <SoftwareSerial.h>
+
+// On ESP8266:
+// Local EspSoftwareSerial loopback, connect D5 (rx) and D6 (tx).
+// For local hardware loopback, connect D5 to D8 (tx), D6 to D7 (rx).
+// For hardware send/sink, connect D7 (rx) and D8 (tx).
+// Hint: The logger is run at 9600bps such that enableIntTx(true) can remain unchanged. Blocking
+// interrupts severely impacts the ability of the EspSoftwareSerial devices to operate concurrently
+// and/or in duplex mode.
+// Operating in software serial full duplex mode, runs at 19200bps and few errors (~2.5%).
+// Operating in software serial half duplex mode (both loopback and repeater),
+// runs at 57600bps with nearly no errors.
+// Operating loopback in full duplex, and repeater in half duplex, runs at 38400bps with nearly no errors.
+// On ESP32:
+// For EspSoftwareSerial or hardware send/sink, connect D5 (rx) and D6 (tx).
+// Hardware Serial2 defaults to D4 (rx), D3 (tx).
+// For local hardware loopback, connect D5 (rx) to D3 (tx), D6 (tx) to D4 (rx).
+
+#ifndef D5
+#if defined(ESP8266)
+#define D8 (15)
+#define D5 (14)
+#define D7 (13)
+#define D6 (12)
+#define RX (3)
+#define TX (1)
+#elif defined(ESP32)
+#define D8 (5)
+#define D5 (18)
+#define D7 (23)
+#define D6 (19)
+#define RX (3)
+#define TX (1)
+#endif
+#endif
+
+// Pick only one of HWLOOPBACK, HWSOURCESWSINK, or HWSOURCESINK
+//#define HWLOOPBACK 1
+//#define HWSOURCESWSINK 1
+//#define HWSOURCESINK 1
+#define HALFDUPLEX 1
+
+#ifdef ESP32
+constexpr int IUTBITRATE = 19200;
+#else
+constexpr int IUTBITRATE = 19200;
+#endif
+
+#if defined(ESP8266)
+constexpr EspSoftwareSerial::Config swSerialConfig = EspSoftwareSerial::SWSERIAL_8E1;
+constexpr SerialConfig hwSerialConfig = ::SERIAL_8E1;
+#elif defined(ESP32)
+constexpr EspSoftwareSerial::Config swSerialConfig = EspSoftwareSerial::SWSERIAL_8E1;
+constexpr uint32_t hwSerialConfig = ::SERIAL_8E1;
+#else
+constexpr unsigned swSerialConfig = 3;
+#endif
+constexpr bool invert = false;
+
+constexpr int BLOCKSIZE = 16; // use fractions of 256
+
+unsigned long start;
+const char effTxTxt[] PROGMEM = "eff. tx: ";
+const char effRxTxt[] PROGMEM = "eff. rx: ";
+int txCount;
+int rxCount;
+int expected;
+int rxErrors;
+int rxParityErrors;
+constexpr int ReportInterval = IUTBITRATE / 8;
+
+#if defined(ESP8266)
+#if defined(HWLOOPBACK) || defined(HWSOURCESWSINK)
+HardwareSerial& hwSerial(Serial);
+EspSoftwareSerial::UART serialIUT;
+EspSoftwareSerial::UART logger;
+#elif defined(HWSOURCESINK)
+HardwareSerial& serialIUT(Serial);
+EspSoftwareSerial::UART logger;
+#else
+EspSoftwareSerial::UART serialIUT;
+HardwareSerial& logger(Serial);
+#endif
+#elif defined(ESP32)
+#if defined(HWLOOPBACK) || defined (HWSOURCESWSINK)
+HardwareSerial& hwSerial(Serial2);
+EspSoftwareSerial::UART serialIUT;
+#elif defined(HWSOURCESINK)
+HardwareSerial& serialIUT(Serial2);
+#else
+EspSoftwareSerial::UART serialIUT;
+#endif
+HardwareSerial& logger(Serial);
+#else
+EspSoftwareSerial::UART serialIUT(14, 12);
+HardwareSerial& logger(Serial);
+#endif
+
+void setup() {
+#if defined(ESP8266)
+#if defined(HWLOOPBACK) || defined(HWSOURCESINK) || defined(HWSOURCESWSINK)
+    Serial.begin(IUTBITRATE, hwSerialConfig, ::SERIAL_FULL, 1, invert);
+    Serial.swap();
+    Serial.setRxBufferSize(2 * BLOCKSIZE);
+    logger.begin(9600, EspSoftwareSerial::SWSERIAL_8N1, -1, TX);
+#else
+    logger.begin(9600);
+#endif
+#if !defined(HWSOURCESINK)
+    serialIUT.begin(IUTBITRATE, swSerialConfig, D5, D6, invert, 2 * BLOCKSIZE);
+#ifdef HALFDUPLEX
+    serialIUT.enableIntTx(false);
+#endif
+#endif
+#elif defined(ESP32)
+#if defined(HWLOOPBACK) || defined(HWSOURCESWSINK)
+    Serial2.begin(IUTBITRATE, hwSerialConfig, D4, D3, invert);
+    Serial2.setRxBufferSize(2 * BLOCKSIZE);
+#elif defined(HWSOURCESINK)
+    serialIUT.begin(IUTBITRATE, hwSerialConfig, D5, D6, invert);
+    serialIUT.setRxBufferSize(2 * BLOCKSIZE);
+#endif
+#if !defined(HWSOURCESINK)
+    serialIUT.begin(IUTBITRATE, swSerialConfig, D5, D6, invert, 2 * BLOCKSIZE);
+#ifdef HALFDUPLEX
+    serialIUT.enableIntTx(false);
+#endif
+#endif
+    logger.begin(9600);
+#else
+#if !defined(HWSOURCESINK)
+    serialIUT.begin(IUTBITRATE);
+#endif
+    logger.begin(9600);
+#endif
+
+    logger.println(PSTR("Loopback example for EspEspSoftwareSerial"));
+
+    start = micros();
+    txCount = 0;
+    rxCount = 0;
+    rxErrors = 0;
+    rxParityErrors = 0;
+    expected = -1;
+}
+
+unsigned char c = 0;
+
+void loop() {
+#ifdef HALFDUPLEX
+    char block[BLOCKSIZE];
+#endif
+    char inBuf[BLOCKSIZE];
+    for (int i = 0; i < BLOCKSIZE; ++i) {
+#ifndef HALFDUPLEX
+#ifdef HWSOURCESWSINK
+        hwSerial.write(c);
+#else
+        serialIUT.write(c);
+#endif
+#ifdef HWLOOPBACK
+        int avail = hwSerial.available();
+        while ((0 == (i % 8)) && avail > 0) {
+            int inCnt = hwSerial.read(inBuf, min(avail, min(BLOCKSIZE, hwSerial.availableForWrite())));
+            hwSerial.write(inBuf, inCnt);
+            avail -= inCnt;
+        }
+#endif
+#else
+        block[i] = c;
+#endif
+        c = (c + 1) % 256;
+        ++txCount;
+    }
+#ifdef HALFDUPLEX
+#ifdef HWSOURCESWSINK
+    hwSerial.write(block, BLOCKSIZE);
+#else
+    serialIUT.write(block, BLOCKSIZE);
+#endif
+#endif
+#ifdef HWSOURCESINK
+#if defined(ESP8266)
+    if (serialIUT.hasOverrun()) { logger.println(PSTR("serialIUT.overrun")); }
+#endif
+#else
+    if (serialIUT.overflow()) { logger.println(PSTR("serialIUT.overflow")); }
+#endif
+
+    int inCnt;
+    uint32_t deadlineStart;
+
+#ifdef HWLOOPBACK
+    // starting deadline for the first bytes to become readable
+    deadlineStart = ESP.getCycleCount();
+    inCnt = 0;
+    while ((ESP.getCycleCount() - deadlineStart) < (1000000UL * 12 * BLOCKSIZE) / IUTBITRATE * 24 * ESP.getCpuFreqMHz()) {
+        int avail = hwSerial.available();
+        inCnt += hwSerial.read(&inBuf[inCnt], min(avail, min(BLOCKSIZE - inCnt, hwSerial.availableForWrite())));
+        if (inCnt >= BLOCKSIZE) { break; }
+        // wait for more outstanding bytes to trickle in
+        if (avail) deadlineStart = ESP.getCycleCount();
+    }
+    hwSerial.write(inBuf, inCnt);
+#endif
+
+    // starting deadline for the first bytes to come in
+    deadlineStart = ESP.getCycleCount();
+    inCnt = 0;
+    while ((ESP.getCycleCount() - deadlineStart) < (1000000UL * 12 * BLOCKSIZE) / IUTBITRATE * 8 * ESP.getCpuFreqMHz()) {
+        int avail;
+        if (0 != (swSerialConfig & 070))
+            avail = serialIUT.available();
+        else
+            avail = serialIUT.read(inBuf, BLOCKSIZE);
+        for (int i = 0; i < avail; ++i)
+        {
+            unsigned char r;
+            if (0 != (swSerialConfig & 070))
+                r = serialIUT.read();
+            else
+                r = inBuf[i];
+            if (expected == -1) { expected = r; }
+            else {
+                expected = (expected + 1) % (1UL << (5 + swSerialConfig % 4));
+            }
+            if (r != expected) {
+                ++rxErrors;
+                expected = -1;
+            }
+#ifndef HWSOURCESINK
+            if (serialIUT.readParity() != (static_cast<bool>(swSerialConfig & 010) ? serialIUT.parityOdd(r) : serialIUT.parityEven(r)))
+            {
+                ++rxParityErrors;
+            }
+#elif defined(ESP8266)
+            // current ESP8266 API does not flag parity errors separately
+            if (serialIUT.hasRxError())
+            {
+                ++rxParityErrors;
+            }
+#endif
+            ++rxCount;
+            ++inCnt;
+        }
+
+        if (inCnt >= BLOCKSIZE) { break; }
+        // wait for more outstanding bytes to trickle in
+        if (avail) deadlineStart = ESP.getCycleCount();
+    }
+
+    const uint32_t interval = micros() - start;
+    if (txCount >= ReportInterval && interval) {
+        uint8_t wordBits = (5 + swSerialConfig % 4) + static_cast<bool>(swSerialConfig & 070) + 1 + ((swSerialConfig & 0300) ? 1 : 0);
+        logger.println(String(PSTR("tx/rx: ")) + txCount + PSTR("/") + rxCount);
+        const long txCps = txCount * (1000000.0 / interval);
+        const long rxCps = rxCount * (1000000.0 / interval);
+        logger.print(String(FPSTR(effTxTxt)) + wordBits * txCps + PSTR("bps, ")
+            + effRxTxt + wordBits * rxCps + PSTR("bps, ")
+            + rxErrors + PSTR(" errors (") + 100.0 * rxErrors / (!rxErrors ? 1 : rxCount) + PSTR("%)"));
+        if (0 != (swSerialConfig & 070))
+        {
+            logger.print(PSTR(" (")); logger.print(rxParityErrors); logger.println(PSTR(" parity errors)"));
+        }
+        else
+        {
+            logger.println();
+        }
+        txCount = 0;
+        rxCount = 0;
+        rxErrors = 0;
+        rxParityErrors = 0;
+        expected = -1;
+        // resync
+        delay(1000UL * 12 * BLOCKSIZE / IUTBITRATE * 16);
+        serialIUT.flush();
+        start = micros();
+    }
+}

src/EspSoftwareSerial/examples/onewiretest/onewiretest.ino

@@ -0,0 +1,59 @@
+#include "SoftwareSerial.h"
+
+#ifndef D5
+#if defined(ESP8266)
+#define D5 (14)
+#define D6 (12)
+#elif defined(ESP32)
+#define D5 (18)
+#define D6 (19)
+#endif
+#endif
+
+EspSoftwareSerial::UART swSer1;
+EspSoftwareSerial::UART swSer2;
+
+void checkSwSerial(EspSoftwareSerial::UART* ss) {
+	byte ch;
+	while (!Serial.available());
+	ss->enableTx(true);
+	while (Serial.available()) {
+		ch = Serial.read();
+		ss->write(ch);
+	}
+	ss->enableTx(false);
+	// wait 1 second for the reply from EspSoftwareSerial if any
+	delay(1000);
+	if (ss->available()) {
+		Serial.print(PSTR("\nResult:"));
+		while (ss->available()) {
+			ch = (byte)ss->read();
+			Serial.print(ch < 0x10 ? PSTR(" 0") : PSTR(" "));
+			Serial.print(ch, HEX);
+		}
+		Serial.println();
+	}
+}
+
+void setup() {
+	delay(2000);
+	Serial.begin(115200);
+	Serial.println(PSTR("\nOne Wire Half Duplex Serial Tester"));
+	swSer1.begin(115200, EspSoftwareSerial::SWSERIAL_8N1, D6, D6, false, 256);
+	// high speed half duplex, turn off interrupts during tx
+	swSer1.enableIntTx(false);
+	swSer2.begin(115200, EspSoftwareSerial::SWSERIAL_8N1, D5, D5, false, 256);
+	// high speed half duplex, turn off interrupts during tx
+	swSer2.enableIntTx(false);
+}
+
+void loop() {
+	Serial.println(PSTR("\n\nTesting on swSer1"));
+	Serial.print(PSTR("Enter something to send using swSer1."));
+	checkSwSerial(&swSer1);
+
+	Serial.println(PSTR("\n\nTesting on swSer2"));
+	Serial.print(PSTR("Enter something to send using swSer2."));
+	checkSwSerial(&swSer2);
+
+}

src/EspSoftwareSerial/examples/onreceive/onreceive.ino

@@ -0,0 +1,80 @@
+// On ESP8266:
+// Runs up to 115200bps at 80MHz, 250000bps at 160MHz, with nearly zero errors.
+// This example is currently not ported to ESP32, which is based on FreeRTOS.
+
+#include <SoftwareSerial.h>
+
+#ifndef D5
+#define D8 (15)
+#define D5 (14)
+#define D7 (13)
+#define D6 (12)
+#define RX (3)
+#define TX (1)
+#endif
+
+#define BAUD_RATE 115200
+#define MAX_FRAMEBITS (1 + 8 + 1 + 2)
+
+EspSoftwareSerial::UART testSerial;
+
+// Becomes set from ISR / IRQ callback function.
+std::atomic<bool> rxPending(false);
+
+void IRAM_ATTR receiveHandler() {
+	rxPending.store(true);
+	esp_schedule();
+}
+
+void setup() {
+	Serial.begin(115200);
+	Serial.setDebugOutput(false);
+	Serial.swap();
+	testSerial.begin(BAUD_RATE, EspSoftwareSerial::SWSERIAL_8N1, RX, TX);
+	// Only half duplex this way, but reliable TX timings for high bps
+	testSerial.enableIntTx(false);
+	testSerial.onReceive(receiveHandler);
+
+	testSerial.println(PSTR("\nSoftware serial onReceive() event test started"));
+
+	for (char ch = ' '; ch <= 'z'; ch++) {
+		testSerial.write(ch);
+	}
+	testSerial.println();
+}
+
+void loop() {
+#ifdef ESP8266
+	bool isRxPending = rxPending.load();
+	if (isRxPending) {
+		rxPending.store(false);
+	}
+#else
+	bool isRxPending = m_isrOverflow.exchange(false);
+#endif
+	auto avail = testSerial.available();
+	if (isRxPending && !avail) {
+		// event fired on start bit, wait until first stop bit of longest frame
+		delayMicroseconds(1 + MAX_FRAMEBITS * 1000000 / BAUD_RATE);
+		avail = testSerial.available();
+	}
+	if (!avail) {
+		// On development board, idle power draw at USB:
+		// with yield() 77mA, 385mW (160MHz: 82mA, 410mW)
+		// with esp_suspend() 20mA, 100mW (at 160MHz, too)
+		//yield();
+		esp_suspend();
+		return;
+	}
+	// try to force to half-duplex
+	decltype(avail) prev_avail;
+	do {
+		delayMicroseconds(1 + MAX_FRAMEBITS * 1000000 / BAUD_RATE);
+		prev_avail = avail;
+	} while (prev_avail != (avail = testSerial.available()));
+	while (avail > 0) {
+		testSerial.write(testSerial.read());
+		avail = testSerial.available();
+	}
+	testSerial.println();
+}

src/EspSoftwareSerial/examples/repeater/repeater.ino

@@ -0,0 +1,199 @@
+#include <SoftwareSerial.h>
+
+// On ESP8266:
+// EspSoftwareSerial loopback for remote source (loopback.ino), or hardware loopback.
+// Connect source D5 (rx) to local D8 (tx), source D6 (tx) to local D7 (rx).
+// Hint: The logger is run at 9600bps such that enableIntTx(true) can remain unchanged. Blocking
+// interrupts severely impacts the ability of the EspSoftwareSerial devices to operate concurrently
+// and/or in duplex mode.
+// On ESP32:
+// For software or hardware loopback, connect source rx to local D8 (tx), source tx to local D7 (rx).
+
+#ifndef D5
+#if defined(ESP8266)
+#define D8 (15)
+#define D5 (14)
+#define D7 (13)
+#define D6 (12)
+#define RX (3)
+#define TX (1)
+#elif defined(ESP32)
+#define D8 (5)
+#define D5 (18)
+#define D7 (23)
+#define D6 (19)
+#define RX (3)
+#define TX (1)
+#endif
+#endif
+
+#define HWLOOPBACK 1
+#define HALFDUPLEX 1
+
+#ifdef ESP32
+constexpr int IUTBITRATE = 19200;
+#else
+constexpr int IUTBITRATE = 19200;
+#endif
+
+#if defined(ESP8266)
+constexpr EspSoftwareSerial::Config swSerialConfig = EspSoftwareSerial::SWSERIAL_8E1;
+constexpr SerialConfig hwSerialConfig = ::SERIAL_8E1;
+#elif defined(ESP32)
+constexpr EspSoftwareSerial::Config swSerialConfig = EspSoftwareSerial::SWSERIAL_8E1;
+constexpr uint32_t hwSerialConfig = ::SERIAL_8E1;
+#else
+constexpr unsigned swSerialConfig = 3;
+#endif
+constexpr bool invert = false;
+
+constexpr int BLOCKSIZE = 16; // use fractions of 256
+
+unsigned long start;
+const char bitRateTxt[] PROGMEM = "Effective data rate: ";
+int rxCount;
+int seqErrors;
+int parityErrors;
+int expected;
+constexpr int ReportInterval = IUTBITRATE / 8;
+
+#if defined(ESP8266)
+#if defined(HWLOOPBACK)
+HardwareSerial& repeater(Serial);
+EspSoftwareSerial::UART logger;
+#else
+EspSoftwareSerial::UART repeater;
+HardwareSerial& logger(Serial);
+#endif
+#elif defined(ESP32)
+#if defined(HWLOOPBACK)
+HardwareSerial& repeater(Serial2);
+#else
+EspSoftwareSerial::UART repeater;
+#endif
+HardwareSerial& logger(Serial);
+#else
+EspSoftwareSerial::UART repeater(14, 12);
+HardwareSerial& logger(Serial);
+#endif
+
+void setup() {
+#if defined(ESP8266)
+#if defined(HWLOOPBACK)
+    repeater.begin(IUTBITRATE, hwSerialConfig, ::SERIAL_FULL, 1, invert);
+    repeater.swap();
+    repeater.setRxBufferSize(2 * BLOCKSIZE);
+    logger.begin(9600, EspSoftwareSerial::SWSERIAL_8N1, -1, TX);
+#else
+    repeater.begin(IUTBITRATE, swSerialConfig, D7, D8, invert, 4 * BLOCKSIZE);
+#ifdef HALFDUPLEX
+    repeater.enableIntTx(false);
+#endif
+    logger.begin(9600);
+#endif
+#elif defined(ESP32)
+#if defined(HWLOOPBACK)
+    repeater.begin(IUTBITRATE, hwSerialConfig, D7, D8, invert);
+    repeater.setRxBufferSize(2 * BLOCKSIZE);
+#else
+    repeater.begin(IUTBITRATE, swSerialConfig, D7, D8, invert, 4 * BLOCKSIZE);
+#ifdef HALFDUPLEX
+    repeater.enableIntTx(false);
+#endif
+#endif
+    logger.begin(9600);
+#else
+    repeater.begin(IUTBITRATE);
+    logger.begin(9600);
+#endif
+
+    logger.println(PSTR("Repeater example for EspEspSoftwareSerial"));
+    start = micros();
+    rxCount = 0;
+    seqErrors = 0;
+    parityErrors = 0;
+    expected = -1;
+}
+
+void loop() {
+#ifdef HWLOOPBACK
+#if defined(ESP8266)
+    if (repeater.hasOverrun()) { logger.println(PSTR("repeater.overrun")); }
+#endif
+#else
+    if (repeater.overflow()) { logger.println(PSTR("repeater.overflow")); }
+#endif
+
+#ifdef HALFDUPLEX
+    char block[BLOCKSIZE];
+#endif
+    // starting deadline for the first bytes to come in
+    uint32_t deadlineStart = ESP.getCycleCount();
+    int inCnt = 0;
+    while ((ESP.getCycleCount() - deadlineStart) < (1000000UL * 12 * BLOCKSIZE) / IUTBITRATE * 24 * ESP.getCpuFreqMHz()) {
+        int avail = repeater.available();
+        for (int i = 0; i < avail; ++i)
+        {
+            int r = repeater.read();
+            if (r == -1) { logger.println(PSTR("read() == -1")); }
+            if (expected == -1) { expected = r; }
+            else {
+                expected = (expected + 1) % (1UL << (5 + swSerialConfig % 4));
+            }
+            if (r != expected) {
+                ++seqErrors;
+                expected = -1;
+            }
+#ifndef HWLOOPBACK
+            if (repeater.readParity() != (static_cast<bool>(swSerialConfig & 010) ? repeater.parityOdd(r) : repeater.parityEven(r)))
+            {
+                ++parityErrors;
+            }
+#elif defined(ESP8266)
+            // current ESP8266 API does not flag parity errors separately
+            if (repeater.hasRxError())
+            {
+                ++parityErrors;
+            }
+#endif
+            ++rxCount;
+#ifdef HALFDUPLEX
+            block[inCnt] = r;
+#else
+            repeater.write(r);
+#endif
+            if (++inCnt >= BLOCKSIZE) { break; }
+        }
+        if (inCnt >= BLOCKSIZE) { break; }
+        // wait for more outstanding bytes to trickle in
+        if (avail) deadlineStart = ESP.getCycleCount();
+    }
+
+#ifdef HALFDUPLEX
+    repeater.write(block, inCnt);
+#endif
+
+    if (rxCount >= ReportInterval) {
+        auto end = micros();
+        unsigned long interval = end - start;
+        long cps = rxCount * (1000000.0 / interval);
+        long seqErrorsps = seqErrors * (1000000.0 / interval);
+        logger.print(String(FPSTR(bitRateTxt)) + 10 * cps + PSTR("bps, ")
+            + seqErrorsps + PSTR("cps seq. errors (") + 100.0 * seqErrors / rxCount + PSTR("%)"));
+#ifndef HWLOOPBACK
+        if (0 != (swSerialConfig & 070))
+        {
+            logger.print(PSTR(" (")); logger.print(parityErrors); logger.println(PSTR(" parity errors)"));
+        }
+        else
+#endif
+        {
+            logger.println();
+        }
+        start = end;
+        rxCount = 0;
+        seqErrors = 0;
+        parityErrors = 0;
+        expected = -1;
+    }
+}

src/EspSoftwareSerial/examples/swsertest/swsertest.ino

@@ -0,0 +1,79 @@
+// On ESP8266:
+// At 80MHz runs up 57600bps, and at 160MHz CPU frequency up to 115200bps with only negligible errors.
+// Connect pin 13 to 15.
+// For verification and as a example for how to use SW serial on the USB to PC connection,
+// which allows the use of HW Serial on GPIO13 and GPIO15 instead, #define SWAPSERIAL below.
+// Notice how the bitrates are also swapped then between RX/TX and GPIO13/GPIO15.
+// Builtin debug output etc. must be stopped on HW Serial in this case, as it would interfere with the
+// external communication on GPIO13/GPIO15.
+
+#include <SoftwareSerial.h>
+
+#ifndef D5
+#if defined(ESP8266)
+#define D8 (15)
+#define D5 (14)
+#define D7 (13)
+#define D6 (12)
+#define RX (3)
+#define TX (1)
+#elif defined(ESP32)
+#define D8 (5)
+#define D5 (18)
+#define D7 (23)
+#define D6 (19)
+#define RX (3)
+#define TX (1)
+#endif
+#endif
+
+#ifdef ESP32
+#define BAUD_RATE 57600
+#else
+#define BAUD_RATE 57600
+#endif
+
+#undef SWAPSERIAL
+
+#ifndef SWAPSERIAL
+auto& usbSerial = Serial;
+EspSoftwareSerial::UART testSerial;
+#else
+EspSoftwareSerial::UART usbSerial;
+auto& testSerial = Serial;
+#endif
+
+void setup() {
+#ifndef SWAPSERIAL
+    usbSerial.begin(115200);
+    // Important: the buffer size optimizations here, in particular the isrBufSize (11) that is only sufficiently
+    // large to hold a single word (up to start - 8 data - parity - stop), are on the basis that any char written
+    // to the loopback EspSoftwareSerial adapter gets read before another write is performed.
+    // Block writes with a size greater than 1 would usually fail. Do not copy this into your own project without
+    // reading the documentation.
+    testSerial.begin(BAUD_RATE, EspSoftwareSerial::SWSERIAL_8N1, D7, D8, false, 95, 11);
+#else
+    testSerial.begin(115200);
+    testSerial.setDebugOutput(false);
+    testSerial.swap();
+    usbSerial.begin(BAUD_RATE, EspSoftwareSerial::SWSERIAL_8N1, RX, TX, false, 95);
+#endif
+
+    usbSerial.println(PSTR("\nSoftware serial test started"));
+
+    for (char ch = ' '; ch <= 'z'; ch++) {
+        testSerial.write(ch);
+    }
+    testSerial.println();
+}
+
+void loop() {
+    while (testSerial.available() > 0) {
+        usbSerial.write(testSerial.read());
+        yield();
+    }
+    while (usbSerial.available() > 0) {
+        testSerial.write(usbSerial.read());
+        yield();
+    }
+}

src/EspSoftwareSerial/keywords.txt

@@ -0,0 +1,43 @@
+#######################################
+# Syntax Coloring Map for EspSoftwareSerial
+# (esp8266)
+#######################################
+
+#######################################
+# Datatypes (KEYWORD1)
+#######################################
+
+EspSoftwareSerial	KEYWORD1
+SoftwareSerial	KEYWORD1
+
+#######################################
+# Methods and Functions (KEYWORD2)
+#######################################
+
+begin	KEYWORD2
+baudRate	KEYWORD2
+setTransmitEnablePin	KEYWORD2
+enableIntTx	KEYWORD2
+overflow	KEYWORD2
+available	KEYWORD2
+peek	KEYWORD2
+read	KEYWORD2
+flush	KEYWORD2
+write	KEYWORD2
+enableRx	KEYWORD2
+enableTx	KEYWORD2
+listen	KEYWORD2
+end	KEYWORD2
+isListening	KEYWORD2
+stopListening	KEYWORD2
+onReceive	KEYWORD2
+
+#######################################
+# Constants (LITERAL1)
+#######################################
+
+SW_SERIAL_UNUSED_PIN	LITERAL1
+SWSERIAL_5N1	LITERAL1
+SWSERIAL_6N1	LITERAL1
+SWSERIAL_7N1	LITERAL1
+SWSERIAL_8N1	LITERAL1

src/EspSoftwareSerial/library.json

@@ -0,0 +1,26 @@
+{
+    "name": "EspSoftwareSerial",
+    "version": "8.1.0",
+    "description": "Implementation of the Arduino software serial for ESP8266/ESP32.",
+    "keywords": [
+        "serial", "io", "softwareserial"
+    ],
+    "repository":
+    {
+        "type": "git",
+        "url": "https://github.com/plerup/espsoftwareserial"
+    },
+    "authors": [
+        {
+            "name": "Dirk Kaar"
+        },
+        {
+            "name": "Peter Lerup"
+        }
+    ],
+    "license": "LGPL-2.1+",
+    "frameworks": "arduino",
+    "platforms": [
+        "espressif8266", "espressif32"
+    ]
+}

src/EspSoftwareSerial/library.properties

@@ -0,0 +1,9 @@
+name=EspSoftwareSerial
+version=8.1.0
+author=Dirk Kaar, Peter Lerup
+maintainer=Dirk Kaar <dok@dok-net.net>
+sentence=Implementation of the Arduino software serial for ESP8266/ESP32.
+paragraph=
+category=Signal Input/Output
+url=https://github.com/plerup/espsoftwareserial/
+architectures=esp8266,esp32

src/EspSoftwareSerial/src/SoftwareSerial.cpp

@@ -0,0 +1,621 @@
+/*
+
+SoftwareSerial.cpp - Implementation of the Arduino software serial for ESP8266/ESP32.
+Copyright (c) 2015-2016 Peter Lerup. All rights reserved.
+Copyright (c) 2018-2019 Dirk O. Kaar. All rights reserved.
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#include "SoftwareSerial.h"
+#include <Arduino.h>
+
+using namespace EspSoftwareSerial;
+
+#ifndef ESP32
+uint32_t UARTBase::m_savedPS = 0;
+#else
+portMUX_TYPE UARTBase::m_interruptsMux = portMUX_INITIALIZER_UNLOCKED;
+#endif
+
+ALWAYS_INLINE_ATTR inline void IRAM_ATTR UARTBase::disableInterrupts()
+{
+#ifndef ESP32
+    m_savedPS = xt_rsil(15);
+#else
+    taskENTER_CRITICAL(&m_interruptsMux);
+#endif
+}
+
+ALWAYS_INLINE_ATTR inline void IRAM_ATTR UARTBase::restoreInterrupts()
+{
+#ifndef ESP32
+    xt_wsr_ps(m_savedPS);
+#else
+    taskEXIT_CRITICAL(&m_interruptsMux);
+#endif
+}
+
+constexpr uint8_t BYTE_ALL_BITS_SET = ~static_cast<uint8_t>(0);
+
+UARTBase::UARTBase() {
+}
+
+UARTBase::UARTBase(int8_t rxPin, int8_t txPin, bool invert)
+{
+    m_rxPin = rxPin;
+    m_txPin = txPin;
+    m_invert = invert;
+}
+
+UARTBase::~UARTBase() {
+    end();
+}
+
+void UARTBase::setRxGPIOPinMode() {
+    if (m_rxValid) {
+        pinMode(m_rxPin, m_rxGPIOHasPullUp && m_rxGPIOPullUpEnabled ? INPUT_PULLUP : INPUT);
+    }
+}
+
+void UARTBase::setTxGPIOPinMode() {
+    if (m_txValid) {
+        pinMode(m_txPin, m_txGPIOOpenDrain ? OUTPUT_OPEN_DRAIN : OUTPUT);
+    }
+}
+
+void UARTBase::begin(uint32_t baud, Config config,
+    int8_t rxPin, int8_t txPin,
+    bool invert) {
+    if (-1 != rxPin) m_rxPin = rxPin;
+    if (-1 != txPin) m_txPin = txPin;
+    m_oneWire = (m_rxPin == m_txPin);
+    m_invert = invert;
+    m_dataBits = 5 + (config & 07);
+    m_parityMode = static_cast<Parity>(config & 070);
+    m_stopBits = 1 + ((config & 0300) ? 1 : 0);
+    m_pduBits = m_dataBits + static_cast<bool>(m_parityMode) + m_stopBits;
+    m_bitTicks = (microsToTicks(1000000UL) + baud / 2) / baud;
+    m_intTxEnabled = true;
+}
+
+void UARTBase::beginRx(bool hasPullUp, int bufCapacity, int isrBufCapacity) {
+    m_rxGPIOHasPullUp = hasPullUp;
+    m_rxReg = portInputRegister(digitalPinToPort(m_rxPin));
+    m_rxBitMask = digitalPinToBitMask(m_rxPin);
+    m_buffer.reset(new circular_queue<uint8_t>((bufCapacity > 0) ? bufCapacity : 64));
+    if (m_parityMode)
+    {
+        m_parityBuffer.reset(new circular_queue<uint8_t>((m_buffer->capacity() + 7) / 8));
+        m_parityInPos = m_parityOutPos = 1;
+    }
+    m_isrBuffer.reset(new circular_queue<uint32_t, UARTBase*>((isrBufCapacity > 0) ?
+        isrBufCapacity : m_buffer->capacity() * (2 + m_dataBits + static_cast<bool>(m_parityMode))));
+    if (m_buffer && (!m_parityMode || m_parityBuffer) && m_isrBuffer) {
+        m_rxValid = true;
+        setRxGPIOPinMode();
+    }
+}
+
+void UARTBase::beginTx() {
+#if !defined(ESP8266)
+    m_txReg = portOutputRegister(digitalPinToPort(m_txPin));
+#endif
+    m_txBitMask = digitalPinToBitMask(m_txPin);
+    m_txValid = true;
+    if (!m_oneWire) {
+        setTxGPIOPinMode();
+        digitalWrite(m_txPin, !m_invert);
+    }
+}
+
+void UARTBase::end()
+{
+    enableRx(false);
+    m_txValid = false;
+    if (m_buffer) {
+        m_buffer.reset();
+    }
+    m_parityBuffer.reset();
+    if (m_isrBuffer) {
+        m_isrBuffer.reset();
+    }
+}
+
+uint32_t UARTBase::baudRate() {
+    return 1000000UL / ticksToMicros(m_bitTicks);
+}
+
+void UARTBase::setTransmitEnablePin(int8_t txEnablePin) {
+    if (-1 != txEnablePin) {
+        m_txEnableValid = true;
+        m_txEnablePin = txEnablePin;
+        pinMode(m_txEnablePin, OUTPUT);
+        digitalWrite(m_txEnablePin, LOW);
+    }
+    else {
+        m_txEnableValid = false;
+    }
+}
+
+void UARTBase::enableIntTx(bool on) {
+    m_intTxEnabled = on;
+}
+
+void UARTBase::enableRxGPIOPullUp(bool on) {
+    m_rxGPIOPullUpEnabled = on;
+    setRxGPIOPinMode();
+}
+
+void UARTBase::enableTxGPIOOpenDrain(bool on) {
+    m_txGPIOOpenDrain = on;
+    setTxGPIOPinMode();
+}
+
+void UARTBase::enableTx(bool on) {
+    if (m_txValid && m_oneWire) {
+        if (on) {
+            enableRx(false);
+            setTxGPIOPinMode();
+            digitalWrite(m_txPin, !m_invert);
+        }
+        else {
+            setRxGPIOPinMode();
+            enableRx(true);
+        }
+    }
+}
+
+void UARTBase::enableRx(bool on) {
+    if (m_rxValid && on != m_rxEnabled) {
+        if (on) {
+            m_rxLastBit = m_pduBits - 1;
+            // Init to stop bit level and current tick
+            m_isrLastTick = (microsToTicks(micros()) | 1) ^ m_invert;
+            if (m_bitTicks >= microsToTicks(1000000UL / 74880UL))
+                attachInterruptArg(digitalPinToInterrupt(m_rxPin), reinterpret_cast<void (*)(void*)>(rxBitISR), this, CHANGE);
+            else
+                attachInterruptArg(digitalPinToInterrupt(m_rxPin), reinterpret_cast<void (*)(void*)>(rxBitSyncISR), this, m_invert ? RISING : FALLING);
+        }
+        else {
+            detachInterrupt(digitalPinToInterrupt(m_rxPin));
+        }
+        m_rxEnabled = on;
+    }
+}
+
+int UARTBase::read() {
+    if (!m_rxValid) { return -1; }
+    if (!m_buffer->available()) {
+        rxBits();
+        if (!m_buffer->available()) { return -1; }
+    }
+    auto val = m_buffer->pop();
+    if (m_parityBuffer)
+    {
+        m_lastReadParity = m_parityBuffer->peek() & m_parityOutPos;
+        m_parityOutPos <<= 1;
+        if (!m_parityOutPos)
+        {
+            m_parityOutPos = 1;
+            m_parityBuffer->pop();
+        }
+    }
+    return val;
+}
+
+int UARTBase::read(uint8_t* buffer, size_t size) {
+    if (!m_rxValid) { return 0; }
+    int avail;
+    if (0 == (avail = m_buffer->pop_n(buffer, size))) {
+        rxBits();
+        avail = m_buffer->pop_n(buffer, size);
+    }
+    if (!avail) return 0;
+    if (m_parityBuffer) {
+        uint32_t parityBits = avail;
+        while (m_parityOutPos >>= 1) ++parityBits;
+        m_parityOutPos = (1 << (parityBits % 8));
+        m_parityBuffer->pop_n(nullptr, parityBits / 8);
+    }
+    return avail;
+}
+
+size_t UARTBase::readBytes(uint8_t* buffer, size_t size) {
+    if (!m_rxValid || !size) { return 0; }
+    size_t count = 0;
+    auto start = millis();
+    do {
+        auto readCnt = read(&buffer[count], size - count);
+        count += readCnt;
+        if (count >= size) break;
+        if (readCnt) {
+            start = millis();
+        }
+        else {
+            optimistic_yield(1000UL);
+        }
+    } while (millis() - start < _timeout);
+    return count;
+}
+
+int UARTBase::available() {
+    if (!m_rxValid) { return 0; }
+    rxBits();
+    int avail = m_buffer->available();
+    if (!avail) {
+        optimistic_yield(10000UL);
+    }
+    return avail;
+}
+
+void UARTBase::lazyDelay() {
+    // Reenable interrupts while delaying to avoid other tasks piling up
+    if (!m_intTxEnabled) { restoreInterrupts(); }
+    const auto expired = microsToTicks(micros()) - m_periodStart;
+    const int32_t remaining = m_periodDuration - expired;
+    const uint32_t ms = remaining > 0 ? ticksToMicros(remaining) / 1000UL : 0;
+    if (ms > 0)
+    {
+        delay(ms);
+    }
+    else
+    {
+        optimistic_yield(10000UL);
+    }
+    // Assure that below-ms part of delays are not elided
+    preciseDelay();
+    // Disable interrupts again if applicable
+    if (!m_intTxEnabled) { disableInterrupts(); }
+}
+
+void IRAM_ATTR UARTBase::preciseDelay() {
+    uint32_t ticks;
+    do {
+        ticks = microsToTicks(micros());
+    } while ((ticks - m_periodStart) < m_periodDuration);
+    m_periodDuration = 0;
+    m_periodStart = ticks;
+}
+
+void IRAM_ATTR UARTBase::writePeriod(
+    uint32_t dutyCycle, uint32_t offCycle, bool withStopBit) {
+    preciseDelay();
+    if (dutyCycle)
+    {
+#if defined(ESP8266)
+        if (16 == m_txPin) {
+            GP16O = 1;
+        }
+        else {
+            GPOS = m_txBitMask;
+        }
+#else
+        *m_txReg = *m_txReg | m_txBitMask;
+#endif
+        m_periodDuration += dutyCycle;
+        if (offCycle || (withStopBit && !m_invert)) {
+            if (!withStopBit || m_invert) {
+                preciseDelay();
+            }
+            else {
+                lazyDelay();
+            }
+        }
+    }
+    if (offCycle)
+    {
+#if defined(ESP8266)
+        if (16 == m_txPin) {
+            GP16O = 0;
+        }
+        else {
+            GPOC = m_txBitMask;
+        }
+#else
+        *m_txReg = *m_txReg & ~m_txBitMask;
+#endif
+        m_periodDuration += offCycle;
+        if (withStopBit && m_invert) lazyDelay();
+    }
+}
+
+size_t UARTBase::write(uint8_t byte) {
+    return write(&byte, 1);
+}
+
+size_t UARTBase::write(uint8_t byte, Parity parity) {
+    return write(&byte, 1, parity);
+}
+
+size_t UARTBase::write(const uint8_t* buffer, size_t size) {
+    return write(buffer, size, m_parityMode);
+}
+
+size_t IRAM_ATTR UARTBase::write(const uint8_t* buffer, size_t size, Parity parity) {
+    if (m_rxValid) { rxBits(); }
+    if (!m_txValid) { return -1; }
+
+    if (m_txEnableValid) {
+        digitalWrite(m_txEnablePin, HIGH);
+    }
+    // Stop bit: if inverted, LOW, otherwise HIGH
+    bool b = !m_invert;
+    uint32_t dutyCycle = 0;
+    uint32_t offCycle = 0;
+    if (!m_intTxEnabled) {
+        // Disable interrupts in order to get a clean transmit timing
+        disableInterrupts();
+    }
+    const uint32_t dataMask = ((1UL << m_dataBits) - 1);
+    bool withStopBit = true;
+    m_periodDuration = 0;
+    m_periodStart = microsToTicks(micros());
+    for (size_t cnt = 0; cnt < size; ++cnt) {
+        uint8_t byte = pgm_read_byte(buffer + cnt) & dataMask;
+        // push LSB start-data-parity-stop bit pattern into uint32_t
+        // Stop bits: HIGH
+        uint32_t word = ~0UL;
+        // inverted parity bit, performance tweak for xor all-bits-set word
+        if (parity && m_parityMode)
+        {
+            uint32_t parityBit;
+            switch (parity)
+            {
+            case PARITY_EVEN:
+                // from inverted, so use odd parity
+                parityBit = byte;
+                parityBit ^= parityBit >> 4;
+                parityBit &= 0xf;
+                parityBit = (0x9669 >> parityBit) & 1;
+                break;
+            case PARITY_ODD:
+                // from inverted, so use even parity
+                parityBit = byte;
+                parityBit ^= parityBit >> 4;
+                parityBit &= 0xf;
+                parityBit = (0x6996 >> parityBit) & 1;
+                break;
+            case PARITY_MARK:
+                parityBit = 0;
+                break;
+            case PARITY_SPACE:
+                // suppresses warning parityBit uninitialized
+            default:
+                parityBit = 1;
+                break;
+            }
+            word ^= parityBit;
+        }
+        word <<= m_dataBits;
+        word |= byte;
+        // Start bit: LOW
+        word <<= 1;
+        if (m_invert) word = ~word;
+        for (int i = 0; i <= m_pduBits; ++i) {
+            bool pb = b;
+            b = word & (1UL << i);
+            if (!pb && b) {
+                writePeriod(dutyCycle, offCycle, withStopBit);
+                withStopBit = false;
+                dutyCycle = offCycle = 0;
+            }
+            if (b) {
+                dutyCycle += m_bitTicks;
+            }
+            else {
+                offCycle += m_bitTicks;
+            }
+        }
+        withStopBit = true;
+    }
+    writePeriod(dutyCycle, offCycle, true);
+    if (!m_intTxEnabled) {
+        // restore the interrupt state if applicable
+        restoreInterrupts();
+    }
+    if (m_txEnableValid) {
+        digitalWrite(m_txEnablePin, LOW);
+    }
+    return size;
+}
+
+void UARTBase::flush() {
+    if (!m_rxValid) { return; }
+    m_buffer->flush();
+    if (m_parityBuffer)
+    {
+        m_parityInPos = m_parityOutPos = 1;
+        m_parityBuffer->flush();
+    }
+}
+
+bool UARTBase::overflow() {
+    bool res = m_overflow;
+    m_overflow = false;
+    return res;
+}
+
+int UARTBase::peek() {
+    if (!m_rxValid) { return -1; }
+    if (!m_buffer->available()) {
+        rxBits();
+        if (!m_buffer->available()) return -1;
+    }
+    auto val = m_buffer->peek();
+    if (m_parityBuffer) m_lastReadParity = m_parityBuffer->peek() & m_parityOutPos;
+    return val;
+}
+
+void UARTBase::rxBits() {
+#ifdef ESP8266
+    if (m_isrOverflow.load()) {
+        m_overflow = true;
+        m_isrOverflow.store(false);
+    }
+#else
+    if (m_isrOverflow.exchange(false)) {
+        m_overflow = true;
+    }
+#endif
+
+    m_isrBuffer->for_each(m_isrBufferForEachDel);
+
+    // A stop bit can go undetected if leading data bits are at same level
+    // and there was also no next start bit yet, so one word may be pending.
+    // Check that there was no new ISR data received in the meantime, inserting an
+    // extraneous stop level bit out of sequence breaks rx.
+    if (m_rxLastBit < m_pduBits - 1) {
+        const uint32_t detectionTicks = (m_pduBits - 1 - m_rxLastBit) * m_bitTicks;
+        if (!m_isrBuffer->available() && microsToTicks(micros()) - m_isrLastTick > detectionTicks) {
+            // Produce faux stop bit level, prevents start bit maldetection
+            // tick's LSB is repurposed for the level bit
+            rxBits(((m_isrLastTick + detectionTicks) | 1) ^ m_invert);
+        }
+    }
+}
+
+void UARTBase::rxBits(const uint32_t isrTick) {
+    const bool level = (m_isrLastTick & 1) ^ m_invert;
+
+    // error introduced by edge value in LSB of isrTick is negligible
+    uint32_t ticks = isrTick - m_isrLastTick;
+    m_isrLastTick = isrTick;
+
+    uint32_t bits = ticks / m_bitTicks;
+    if (ticks % m_bitTicks > (m_bitTicks >> 1)) ++bits;
+    while (bits > 0) {
+        // start bit detection
+        if (m_rxLastBit >= (m_pduBits - 1)) {
+            // leading edge of start bit?
+            if (level) break;
+            m_rxLastBit = -1;
+            --bits;
+            continue;
+        }
+        // data bits
+        if (m_rxLastBit < (m_dataBits - 1)) {
+            uint8_t dataBits = min(bits, static_cast<uint32_t>(m_dataBits - 1 - m_rxLastBit));
+            m_rxLastBit += dataBits;
+            bits -= dataBits;
+            m_rxCurByte >>= dataBits;
+            if (level) { m_rxCurByte |= (BYTE_ALL_BITS_SET << (8 - dataBits)); }
+            continue;
+        }
+        // parity bit
+        if (m_parityMode && m_rxLastBit == (m_dataBits - 1)) {
+            ++m_rxLastBit;
+            --bits;
+            m_rxCurParity = level;
+            continue;
+        }
+        // stop bits
+        // Store the received value in the buffer unless we have an overflow
+        // if not high stop bit level, discard word
+        if (bits >= static_cast<uint32_t>(m_pduBits - 1 - m_rxLastBit) && level) {
+            m_rxCurByte >>= (sizeof(uint8_t) * 8 - m_dataBits);
+            if (!m_buffer->push(m_rxCurByte)) {
+                m_overflow = true;
+            }
+            else {
+                if (m_parityBuffer)
+                {
+                    if (m_rxCurParity) {
+                        m_parityBuffer->pushpeek() |= m_parityInPos;
+                    }
+                    else {
+                        m_parityBuffer->pushpeek() &= ~m_parityInPos;
+                    }
+                    m_parityInPos <<= 1;
+                    if (!m_parityInPos)
+                    {
+                        m_parityBuffer->push();
+                        m_parityInPos = 1;
+                    }
+                }
+            }
+        }
+        m_rxLastBit = m_pduBits - 1;
+        // reset to 0 is important for masked bit logic
+        m_rxCurByte = 0;
+        m_rxCurParity = false;
+        break;
+    }
+}
+
+void IRAM_ATTR UARTBase::rxBitISR(UARTBase* self) {
+    const bool level = *self->m_rxReg & self->m_rxBitMask;
+    const uint32_t curTick = microsToTicks(micros());
+    const bool empty = !self->m_isrBuffer->available();
+
+    // Store level and tick in the buffer unless we have an overflow
+    // tick's LSB is repurposed for the level bit
+    if (!self->m_isrBuffer->push((curTick | 1U) ^ !level)) self->m_isrOverflow.store(true);
+    // Trigger rx callback only when receiver is starved
+    if (empty) self->m_rxHandler();
+}
+
+void IRAM_ATTR UARTBase::rxBitSyncISR(UARTBase* self) {
+    bool level = self->m_invert;
+    const uint32_t start = microsToTicks(micros());
+    uint32_t wait = self->m_bitTicks;
+    const bool empty = !self->m_isrBuffer->available();
+
+    // Store level and tick in the buffer unless we have an overflow
+    // tick's LSB is repurposed for the level bit
+    if (!self->m_isrBuffer->push(((start + wait) | 1U) ^ !level)) self->m_isrOverflow.store(true);
+
+    for (uint32_t i = 0; i < self->m_pduBits; ++i) {
+        while (microsToTicks(micros()) - start < wait) {};
+        wait += self->m_bitTicks;
+
+        // Store level and tick in the buffer unless we have an overflow
+        // tick's LSB is repurposed for the level bit
+        if (static_cast<bool>(*self->m_rxReg & self->m_rxBitMask) != level)
+        {
+            if (!self->m_isrBuffer->push(((start + wait) | 1U) ^ level)) self->m_isrOverflow.store(true);
+            level = !level;
+        }
+    }
+    // Trigger rx callback only when receiver is starved
+    if (empty) self->m_rxHandler();
+}
+
+void UARTBase::onReceive(const Delegate<void(), void*>& handler) {
+    disableInterrupts();
+    m_rxHandler = handler;
+    restoreInterrupts();
+}
+
+void UARTBase::onReceive(Delegate<void(), void*>&& handler) {
+    disableInterrupts();
+    m_rxHandler = std::move(handler);
+    restoreInterrupts();
+}
+
+#if __GNUC__ < 12
+// The template member functions below must be in IRAM, but due to a bug GCC doesn't currently
+// honor the attribute. Instead, it is possible to do explicit specialization and adorn
+// these with the IRAM attribute:
+// Delegate<>::operator (), circular_queue<>::available,
+// circular_queue<>::available_for_push, circular_queue<>::push_peek, circular_queue<>::push
+
+template void IRAM_ATTR delegate::detail::DelegateImpl<void*, void>::operator()() const;
+template size_t IRAM_ATTR circular_queue<uint32_t, UARTBase*>::available() const;
+template bool IRAM_ATTR circular_queue<uint32_t, UARTBase*>::push(uint32_t&&);
+template bool IRAM_ATTR circular_queue<uint32_t, UARTBase*>::push(const uint32_t&);
+#endif // __GNUC__ < 12
+

src/EspSoftwareSerial/src/SoftwareSerial.h

@@ -0,0 +1,449 @@
+/*
+SoftwareSerial.h - Implementation of the Arduino software serial for ESP8266/ESP32.
+Copyright (c) 2015-2016 Peter Lerup. All rights reserved.
+Copyright (c) 2018-2019 Dirk O. Kaar. All rights reserved.
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+#ifndef __SoftwareSerial_h
+#define __SoftwareSerial_h
+
+#include "circular_queue/circular_queue.h"
+#include <Stream.h>
+
+namespace EspSoftwareSerial {
+
+// Interface definition for template argument of BasicUART
+class IGpioCapabilities {
+public:
+    static constexpr bool isValidPin(int8_t pin);
+    static constexpr bool isValidInputPin(int8_t pin);
+    static constexpr bool isValidOutputPin(int8_t pin);
+    // result is only defined for a valid Rx pin
+    static constexpr bool hasPullUp(int8_t pin);
+};
+
+class GpioCapabilities : private IGpioCapabilities {
+public:
+    static constexpr bool isValidPin(int8_t pin) {
+    #if defined(ESP8266)
+        return (pin >= 0 && pin <= 16) && !isFlashInterfacePin(pin);
+    #elif defined(ESP32)
+        // Remove the strapping pins as defined in the datasheets, they affect bootup and other critical operations
+        // Remmove the flash memory pins on related devices, since using these causes memory access issues.
+    #ifdef CONFIG_IDF_TARGET_ESP32
+        // Datasheet https://www.espressif.com/sites/default/files/documentation/esp32_datasheet_en.pdf,
+        // Pinout    https://docs.espressif.com/projects/esp-idf/en/latest/esp32/_images/esp32-devkitC-v4-pinout.jpg
+        return (pin == 1) || (pin >= 3 && pin <= 5) ||
+            (pin >= 12 && pin <= 15) ||
+            (!psramFound() && pin >= 16 && pin <= 17) ||
+            (pin >= 18 && pin <= 19) ||
+            (pin >= 21 && pin <= 23) || (pin >= 25 && pin <= 27) || (pin >= 32 && pin <= 39);
+    #elif CONFIG_IDF_TARGET_ESP32S2
+        // Datasheet https://www.espressif.com/sites/default/files/documentation/esp32-s2_datasheet_en.pdf,
+        // Pinout    https://docs.espressif.com/projects/esp-idf/en/latest/esp32s2/_images/esp32-s2_saola1-pinout.jpg
+        return (pin >= 1 && pin <= 21) || (pin >= 33 && pin <= 44);
+    #elif CONFIG_IDF_TARGET_ESP32C3
+        // Datasheet https://www.espressif.com/sites/default/files/documentation/esp32-c3_datasheet_en.pdf,
+        // Pinout    https://docs.espressif.com/projects/esp-idf/en/latest/esp32c3/_images/esp32-c3-devkitm-1-v1-pinout.jpg
+        return (pin >= 0 && pin <= 1) || (pin >= 3 && pin <= 7) || (pin >= 18 && pin <= 21);
+    #else
+        return pin >= 0;
+    #endif
+    #else
+        return pin >= 0;
+    #endif
+    }
+
+    static constexpr bool isValidInputPin(int8_t pin) {
+        return isValidPin(pin)
+    #if defined(ESP8266)
+            && (pin != 16)
+    #endif
+            ;
+    }
+
+    static constexpr bool isValidOutputPin(int8_t pin) {
+        return isValidPin(pin)
+    #if defined(ESP32)
+    #ifdef CONFIG_IDF_TARGET_ESP32
+            && (pin < 34)
+    #elif CONFIG_IDF_TARGET_ESP32S2
+            && (pin <= 45)
+    #elif CONFIG_IDF_TARGET_ESP32C3
+            // no restrictions
+    #endif
+    #endif
+            ;
+    }
+
+    // result is only defined for a valid Rx pin
+    static constexpr bool hasPullUp(int8_t pin) {
+    #if defined(ESP32)
+        return !(pin >= 34 && pin <= 39);
+    #else
+        (void)pin;
+        return true;
+    #endif
+    }
+};
+
+enum Parity : uint8_t {
+    PARITY_NONE = 000,
+    PARITY_EVEN = 020,
+    PARITY_ODD = 030,
+    PARITY_MARK = 040,
+    PARITY_SPACE = 070,
+};
+
+enum Config {
+    SWSERIAL_5N1 = PARITY_NONE,
+    SWSERIAL_6N1,
+    SWSERIAL_7N1,
+    SWSERIAL_8N1,
+    SWSERIAL_5E1 = PARITY_EVEN,
+    SWSERIAL_6E1,
+    SWSERIAL_7E1,
+    SWSERIAL_8E1,
+    SWSERIAL_5O1 = PARITY_ODD,
+    SWSERIAL_6O1,
+    SWSERIAL_7O1,
+    SWSERIAL_8O1,
+    SWSERIAL_5M1 = PARITY_MARK,
+    SWSERIAL_6M1,
+    SWSERIAL_7M1,
+    SWSERIAL_8M1,
+    SWSERIAL_5S1 = PARITY_SPACE,
+    SWSERIAL_6S1,
+    SWSERIAL_7S1,
+    SWSERIAL_8S1,
+    SWSERIAL_5N2 = 0200 | PARITY_NONE,
+    SWSERIAL_6N2,
+    SWSERIAL_7N2,
+    SWSERIAL_8N2,
+    SWSERIAL_5E2 = 0200 | PARITY_EVEN,
+    SWSERIAL_6E2,
+    SWSERIAL_7E2,
+    SWSERIAL_8E2,
+    SWSERIAL_5O2 = 0200 | PARITY_ODD,
+    SWSERIAL_6O2,
+    SWSERIAL_7O2,
+    SWSERIAL_8O2,
+    SWSERIAL_5M2 = 0200 | PARITY_MARK,
+    SWSERIAL_6M2,
+    SWSERIAL_7M2,
+    SWSERIAL_8M2,
+    SWSERIAL_5S2 = 0200 | PARITY_SPACE,
+    SWSERIAL_6S2,
+    SWSERIAL_7S2,
+    SWSERIAL_8S2,
+};
+
+/// This class is compatible with the corresponding AVR one, however,
+/// the constructor takes no arguments, for compatibility with the
+/// HardwareSerial class.
+/// Instead, the begin() function handles pin assignments and logic inversion.
+/// It also has optional input buffer capacity arguments for byte buffer and ISR bit buffer.
+/// Bitrates up to at least 115200 can be used.
+class UARTBase : public Stream {
+public:
+    UARTBase();
+    /// Ctor to set defaults for pins.
+    /// @param rxPin the GPIO pin used for RX
+    /// @param txPin -1 for onewire protocol, GPIO pin used for twowire TX
+    UARTBase(int8_t rxPin, int8_t txPin = -1, bool invert = false);
+    UARTBase(const UARTBase&) = delete;
+    UARTBase& operator= (const UARTBase&) = delete;
+    virtual ~UARTBase();
+    /// Configure the UARTBase object for use.
+    /// @param baud the TX/RX bitrate
+    /// @param config sets databits, parity, and stop bit count
+    /// @param rxPin -1 or default: either no RX pin, or keeps the rxPin set in the ctor
+    /// @param txPin -1 or default: either no TX pin (onewire), or keeps the txPin set in the ctor
+    /// @param invert true: uses invert line level logic
+    /// @param bufCapacity the capacity for the received bytes buffer
+    /// @param isrBufCapacity 0: derived from bufCapacity. The capacity of the internal asynchronous
+    ///        bit receive buffer, a suggested size is bufCapacity times the sum of
+    ///        start, data, parity and stop bit count.
+    void begin(uint32_t baud, Config config,
+        int8_t rxPin, int8_t txPin, bool invert);
+
+    uint32_t baudRate();
+    /// Transmit control pin.
+    void setTransmitEnablePin(int8_t txEnablePin);
+    /// Enable (default) or disable interrupts during tx.
+    void enableIntTx(bool on);
+    /// Enable (default) or disable internal rx GPIO pull-up.
+    void enableRxGPIOPullUp(bool on);
+    /// Enable or disable (default) tx GPIO output mode.
+    void enableTxGPIOOpenDrain(bool on);
+
+    bool overflow();
+
+    int available() override;
+#if defined(ESP8266)
+    int availableForWrite() override {
+#else
+    int availableForWrite() {
+#endif
+        if (!m_txValid) return 0;
+        return 1;
+    }
+    int peek() override;
+    int read() override;
+    /// @returns The verbatim parity bit associated with the last successful read() or peek() call
+    bool readParity()
+    {
+        return m_lastReadParity;
+    }
+    /// @returns The calculated bit for even parity of the parameter byte
+    static bool parityEven(uint8_t byte) {
+        byte ^= byte >> 4;
+        byte &= 0xf;
+        return (0x6996 >> byte) & 1;
+    }
+    /// @returns The calculated bit for odd parity of the parameter byte
+    static bool parityOdd(uint8_t byte) {
+        byte ^= byte >> 4;
+        byte &= 0xf;
+        return (0x9669 >> byte) & 1;
+    }
+    /// The read(buffer, size) functions are non-blocking, the same as readBytes but without timeout
+    int read(uint8_t* buffer, size_t size)
+#if defined(ESP8266)
+        override
+#endif
+        ;
+    /// The read(buffer, size) functions are non-blocking, the same as readBytes but without timeout
+    int read(char* buffer, size_t size) {
+        return read(reinterpret_cast<uint8_t*>(buffer), size);
+    }
+    /// @returns The number of bytes read into buffer, up to size. Times out if the limit set through
+    ///          Stream::setTimeout() is reached.
+    size_t readBytes(uint8_t* buffer, size_t size) override;
+    /// @returns The number of bytes read into buffer, up to size. Times out if the limit set through
+    ///          Stream::setTimeout() is reached.
+    size_t readBytes(char* buffer, size_t size) override {
+        return readBytes(reinterpret_cast<uint8_t*>(buffer), size);
+    }
+    void flush() override;
+    size_t write(uint8_t byte) override;
+    size_t write(uint8_t byte, Parity parity);
+    size_t write(const uint8_t* buffer, size_t size) override;
+    size_t write(const char* buffer, size_t size) {
+        return write(reinterpret_cast<const uint8_t*>(buffer), size);
+    }
+    size_t write(const uint8_t* buffer, size_t size, Parity parity);
+    size_t write(const char* buffer, size_t size, Parity parity) {
+        return write(reinterpret_cast<const uint8_t*>(buffer), size, parity);
+    }
+    operator bool() const {
+        return (-1 == m_rxPin || m_rxValid) && (-1 == m_txPin || m_txValid) && !(-1 == m_rxPin && m_oneWire);
+    }
+
+    /// Disable or enable interrupts on the rx pin.
+    void enableRx(bool on);
+    /// One wire control.
+    void enableTx(bool on);
+
+    // AVR compatibility methods.
+    bool listen() { enableRx(true); return true; }
+    void end();
+    bool isListening() { return m_rxEnabled; }
+    bool stopListening() { enableRx(false); return true; }
+
+    /// onReceive sets a callback that will be called in interrupt context
+    /// when data is received.
+    /// More precisely, the callback is triggered when UARTBase detects
+    /// a new reception, which may not yet have completed on invocation.
+    /// Reading - never from this interrupt context - should therefore be
+    /// delayed at least for the duration of one incoming word.
+    void onReceive(const Delegate<void(), void*>& handler);
+    /// onReceive sets a callback that will be called in interrupt context
+    /// when data is received.
+    /// More precisely, the callback is triggered when UARTBase detects
+    /// a new reception, which may not yet have completed on invocation.
+    /// Reading - never from this interrupt context - should therefore be
+    /// delayed at least for the duration of one incoming word.
+    void onReceive(Delegate<void(), void*>&& handler);
+
+    [[deprecated("function removed; semantics of onReceive() changed; check the header file.")]]
+    void perform_work();
+
+    using Print::write;
+
+protected:
+    void beginRx(bool hasPullUp, int bufCapacity, int isrBufCapacity);
+    void beginTx();
+    // Member variables
+    int8_t m_rxPin = -1;
+    int8_t m_txPin = -1;
+    bool m_invert = false;
+
+private:
+    // It's legal to exceed the deadline, for instance,
+    // by enabling interrupts.
+    void lazyDelay();
+    // Synchronous precise delay
+    void preciseDelay();
+    // If withStopBit is set, either cycle contains a stop bit.
+    // If dutyCycle == 0, the level is not forced to HIGH.
+    // If offCycle == 0, the level remains unchanged from dutyCycle.
+    void writePeriod(
+        uint32_t dutyCycle, uint32_t offCycle, bool withStopBit);
+    // safely set the pin mode for the Rx GPIO pin
+    void setRxGPIOPinMode();
+    // safely set the pin mode for the Tx GPIO pin
+    void setTxGPIOPinMode();
+    /* check m_rxValid that calling is safe */
+    void rxBits();
+    void rxBits(const uint32_t isrTick);
+    static void disableInterrupts();
+    static void restoreInterrupts();
+
+    static void rxBitISR(UARTBase* self);
+    static void rxBitSyncISR(UARTBase* self);
+
+    static inline uint32_t IRAM_ATTR microsToTicks(uint32_t micros) ALWAYS_INLINE_ATTR {
+        return micros << 1;
+    }
+    static inline uint32_t ticksToMicros(uint32_t ticks) ALWAYS_INLINE_ATTR {
+        return ticks >> 1;
+    }
+
+    // Member variables
+    volatile uint32_t* m_rxReg;
+    uint32_t m_rxBitMask;
+#if !defined(ESP8266)
+    volatile uint32_t* m_txReg;
+#endif
+    uint32_t m_txBitMask;
+    int8_t m_txEnablePin = -1;
+    uint8_t m_dataBits;
+    bool m_oneWire;
+    bool m_rxValid = false;
+    bool m_rxEnabled = false;
+    bool m_txValid = false;
+    bool m_txEnableValid = false;
+    /// PDU bits include data, parity and stop bits; the start bit is not counted.
+    uint8_t m_pduBits;
+    bool m_intTxEnabled;
+    bool m_rxGPIOHasPullUp = false;
+    bool m_rxGPIOPullUpEnabled = true;
+    bool m_txGPIOOpenDrain = false;
+    Parity m_parityMode;
+    uint8_t m_stopBits;
+    bool m_lastReadParity;
+    bool m_overflow = false;
+    uint32_t m_bitTicks;
+    uint8_t m_parityInPos;
+    uint8_t m_parityOutPos;
+    int8_t m_rxLastBit; // 0 thru (m_pduBits - m_stopBits - 1): data/parity bits. -1: start bit. (m_pduBits - 1): stop bit.
+    uint8_t m_rxCurByte = 0;
+    std::unique_ptr<circular_queue<uint8_t> > m_buffer;
+    std::unique_ptr<circular_queue<uint8_t> > m_parityBuffer;
+    uint32_t m_periodStart;
+    uint32_t m_periodDuration;
+#ifndef ESP32
+    static uint32_t m_savedPS;
+#else
+    static portMUX_TYPE m_interruptsMux;
+#endif
+    // the ISR stores the relative bit times in the buffer. The inversion corrected level is used as sign bit (2's complement):
+    // 1 = positive including 0, 0 = negative.
+    std::unique_ptr<circular_queue<uint32_t, UARTBase*> > m_isrBuffer;
+    const Delegate<void(uint32_t&&), UARTBase*> m_isrBufferForEachDel { [](UARTBase* self, uint32_t&& isrTick) { self->rxBits(isrTick); }, this };
+    std::atomic<bool> m_isrOverflow { false };
+    uint32_t m_isrLastTick;
+    bool m_rxCurParity = false;
+    Delegate<void(), void*> m_rxHandler;
+};
+
+template< class GpioCapabilities > class BasicUART : public UARTBase {
+    static_assert(std::is_base_of<IGpioCapabilities, GpioCapabilities>::value,
+        "template argument is not derived from IGpioCapabilities");
+public:
+    BasicUART() : UARTBase() {
+    }
+    /// Ctor to set defaults for pins.
+    /// @param rxPin the GPIO pin used for RX
+    /// @param txPin -1 for onewire protocol, GPIO pin used for twowire TX
+    BasicUART(int8_t rxPin, int8_t txPin = -1, bool invert = false) :
+        UARTBase(rxPin, txPin, invert) {
+    }
+
+    /// Configure the BasicUART object for use.
+    /// @param baud the TX/RX bitrate
+    /// @param config sets databits, parity, and stop bit count
+    /// @param rxPin -1 or default: either no RX pin, or keeps the rxPin set in the ctor
+    /// @param txPin -1 or default: either no TX pin (onewire), or keeps the txPin set in the ctor
+    /// @param invert true: uses invert line level logic
+    /// @param bufCapacity the capacity for the received bytes buffer
+    /// @param isrBufCapacity 0: derived from bufCapacity. The capacity of the internal asynchronous
+    ///        bit receive buffer, a suggested size is bufCapacity times the sum of
+    ///        start, data, parity and stop bit count.
+    void begin(uint32_t baud, Config config,
+        int8_t rxPin, int8_t txPin, bool invert,
+        int bufCapacity = 64, int isrBufCapacity = 0) {
+        UARTBase::begin(baud, config, rxPin, txPin, invert);
+        if (GpioCapabilities::isValidInputPin(rxPin)) {
+            beginRx(GpioCapabilities:: hasPullUp(rxPin), bufCapacity, isrBufCapacity);
+        }
+        if (GpioCapabilities::isValidOutputPin(txPin)) {
+            beginTx();
+        }
+        enableRx(true);
+    }
+    void begin(uint32_t baud, Config config,
+        int8_t rxPin, int8_t txPin) {
+        begin(baud, config, rxPin, txPin, m_invert);
+    }
+    void begin(uint32_t baud, Config config,
+        int8_t rxPin) {
+        begin(baud, config, rxPin, m_txPin, m_invert);
+    }
+    void begin(uint32_t baud, Config config = SWSERIAL_8N1) {
+        begin(baud, config, m_rxPin, m_txPin, m_invert);
+    }
+    void setTransmitEnablePin(int8_t txEnablePin) {
+        UARTBase::setTransmitEnablePin(
+            GpioCapabilities::isValidOutputPin(txEnablePin) ? txEnablePin : -1);
+    }
+};
+
+using UART = BasicUART< GpioCapabilities >;
+
+}; // namespace EspSoftwareSerial
+
+using SoftwareSerial = EspSoftwareSerial::UART;
+using namespace EspSoftwareSerial;
+
+#if __GNUC__ < 12
+// The template member functions below must be in IRAM, but due to a bug GCC doesn't currently
+// honor the attribute. Instead, it is possible to do explicit specialization and adorn
+// these with the IRAM attribute:
+// Delegate<>::operator (), circular_queue<>::available,
+// circular_queue<>::available_for_push, circular_queue<>::push_peek, circular_queue<>::push
+
+extern template void delegate::detail::DelegateImpl<void*, void>::operator()() const;
+extern template size_t circular_queue<uint32_t, EspSoftwareSerial::UARTBase*>::available() const;
+extern template bool circular_queue<uint32_t, EspSoftwareSerial::UARTBase*>::push(uint32_t&&);
+extern template bool circular_queue<uint32_t, EspSoftwareSerial::UARTBase*>::push(const uint32_t&);
+#endif // __GNUC__ < 12
+
+#endif // __SoftwareSerial_h
+

src/EspSoftwareSerial/src/circular_queue/MultiDelegate.h

@@ -0,0 +1,567 @@
+/*
+MultiDelegate.h - A queue or event multiplexer based on the efficient Delegate
+class
+Copyright (c) 2019-2020 Dirk O. Kaar. All rights reserved.
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#ifndef __MULTIDELEGATE_H
+#define __MULTIDELEGATE_H
+
+#include <iterator>
+#if defined(ESP8266) || defined(ESP32) || !defined(ARDUINO)
+#include <atomic>
+#else
+#include "circular_queue/ghostl.h"
+#endif
+
+#if defined(ESP8266)
+#include <interrupts.h>
+using esp8266::InterruptLock;
+#elif defined(ARDUINO)
+class InterruptLock {
+public:
+    InterruptLock() {
+        noInterrupts();
+    }
+    ~InterruptLock() {
+        interrupts();
+    }
+};
+#else
+#include <mutex>
+#endif
+
+namespace
+{
+
+    template< typename Delegate, typename R, bool ISQUEUE = false, typename... P>
+    struct CallP
+    {
+        static R execute(Delegate& del, P... args)
+        {
+            return del(std::forward<P...>(args...));
+        }
+    };
+
+    template< typename Delegate, bool ISQUEUE, typename... P>
+    struct CallP<Delegate, void, ISQUEUE, P...>
+    {
+        static bool execute(Delegate& del, P... args)
+        {
+            del(std::forward<P...>(args...));
+            return true;
+        }
+    };
+
+    template< typename Delegate, typename R, bool ISQUEUE = false>
+    struct Call
+    {
+        static R execute(Delegate& del)
+        {
+            return del();
+        }
+    };
+
+    template< typename Delegate, bool ISQUEUE>
+    struct Call<Delegate, void, ISQUEUE>
+    {
+        static bool execute(Delegate& del)
+        {
+            del();
+            return true;
+        }
+    };
+
+}
+
+namespace delegate
+{
+    namespace detail
+    {
+
+        template< typename Delegate, typename R, bool ISQUEUE = false, size_t QUEUE_CAPACITY = 32, typename... P>
+        class MultiDelegatePImpl
+        {
+        public:
+            MultiDelegatePImpl() = default;
+            ~MultiDelegatePImpl()
+            {
+                *this = nullptr;
+            }
+
+            MultiDelegatePImpl(const MultiDelegatePImpl&) = delete;
+            MultiDelegatePImpl& operator=(const MultiDelegatePImpl&) = delete;
+
+            MultiDelegatePImpl(MultiDelegatePImpl&& md)
+            {
+                first = md.first;
+                last = md.last;
+                unused = md.unused;
+                nodeCount = md.nodeCount;
+                md.first = nullptr;
+                md.last = nullptr;
+                md.unused = nullptr;
+                md.nodeCount = 0;
+            }
+
+            MultiDelegatePImpl(const Delegate& del)
+            {
+                add(del);
+            }
+
+            MultiDelegatePImpl(Delegate&& del)
+            {
+                add(std::move(del));
+            }
+
+            MultiDelegatePImpl& operator=(MultiDelegatePImpl&& md)
+            {
+                first = md.first;
+                last = md.last;
+                unused = md.unused;
+                nodeCount = md.nodeCount;
+                md.first = nullptr;
+                md.last = nullptr;
+                md.unused = nullptr;
+                md.nodeCount = 0;
+                return *this;
+            }
+
+            MultiDelegatePImpl& operator=(std::nullptr_t)
+            {
+                if (last)
+                    last->mNext = unused;
+                if (first)
+                    unused = first;
+                while (unused)
+                {
+                    auto to_delete = unused;
+                    unused = unused->mNext;
+                    delete(to_delete);
+                }
+                return *this;
+            }
+
+            MultiDelegatePImpl& operator+=(const Delegate& del)
+            {
+                add(del);
+                return *this;
+            }
+
+            MultiDelegatePImpl& operator+=(Delegate&& del)
+            {
+                add(std::move(del));
+                return *this;
+            }
+
+        protected:
+            struct Node_t
+            {
+                ~Node_t()
+                {
+                    mDelegate = nullptr; // special overload in Delegate
+                }
+                Node_t* mNext = nullptr;
+                Delegate mDelegate;
+            };
+
+            Node_t* first = nullptr;
+            Node_t* last = nullptr;
+            Node_t* unused = nullptr;
+            size_t nodeCount = 0;
+
+            // Returns a pointer to an unused Node_t,
+            // or if none are available allocates a new one,
+            // or nullptr if limit is reached
+            Node_t* IRAM_ATTR get_node_unsafe()
+            {
+                Node_t* result = nullptr;
+                // try to get an item from unused items list
+                if (unused)
+                {
+                    result = unused;
+                    unused = unused->mNext;
+                }
+                // if no unused items, and count not too high, allocate a new one
+                else if (nodeCount < QUEUE_CAPACITY)
+                {
+#if defined(ESP8266) || defined(ESP32)            	
+                    result = new (std::nothrow) Node_t;
+#else
+                    result = new Node_t;
+#endif
+                    if (result)
+                        ++nodeCount;
+                }
+                return result;
+            }
+
+            void recycle_node_unsafe(Node_t* node)
+            {
+                node->mDelegate = nullptr; // special overload in Delegate
+                node->mNext = unused;
+                unused = node;
+            }
+
+#ifndef ARDUINO
+            std::mutex mutex_unused;
+#endif
+        public:
+            class iterator : public std::iterator<std::forward_iterator_tag, Delegate>
+            {
+            public:
+                Node_t* current = nullptr;
+                Node_t* prev = nullptr;
+                const Node_t* stop = nullptr;
+
+                iterator(MultiDelegatePImpl& md) : current(md.first), stop(md.last) {}
+                iterator() = default;
+                iterator(const iterator&) = default;
+                iterator& operator=(const iterator&) = default;
+                iterator& operator=(iterator&&) = default;
+                operator bool() const
+                {
+                    return current && stop;
+                }
+                bool operator==(const iterator& rhs) const
+                {
+                    return current == rhs.current;
+                }
+                bool operator!=(const iterator& rhs) const
+                {
+                    return !operator==(rhs);
+                }
+                Delegate& operator*() const
+                {
+                    return current->mDelegate;
+                }
+                Delegate* operator->() const
+                {
+                    return &current->mDelegate;
+                }
+                iterator& operator++() // prefix
+                {
+                    if (current && stop != current)
+                    {
+                        prev = current;
+                        current = current->mNext;
+                    }
+                    else
+                        current = nullptr; // end
+                    return *this;
+                }
+                iterator& operator++(int) // postfix
+                {
+                    iterator tmp(*this);
+                    operator++();
+                    return tmp;
+                }
+            };
+
+            iterator begin()
+            {
+                return iterator(*this);
+            }
+            iterator end() const
+            {
+                return iterator();
+            }
+
+            const Delegate* add(const Delegate& del)
+            {
+                return add(Delegate(del));
+            }
+
+            const Delegate* add(Delegate&& del)
+            {
+                if (!del)
+                    return nullptr;
+
+#ifdef ARDUINO
+                InterruptLock lockAllInterruptsInThisScope;
+#else
+                std::lock_guard<std::mutex> lock(mutex_unused);
+#endif
+
+                Node_t* item = ISQUEUE ? get_node_unsafe() :
+#if defined(ESP8266) || defined(ESP32)            	
+                    new (std::nothrow) Node_t;
+#else
+                    new Node_t;
+#endif
+                if (!item)
+                    return nullptr;
+
+                item->mDelegate = std::move(del);
+                item->mNext = nullptr;
+
+                if (last)
+                    last->mNext = item;
+                else
+                    first = item;
+                last = item;
+
+                return &item->mDelegate;
+            }
+
+            iterator erase(iterator it)
+            {
+                if (!it)
+                    return end();
+#ifdef ARDUINO
+                InterruptLock lockAllInterruptsInThisScope;
+#else
+                std::lock_guard<std::mutex> lock(mutex_unused);
+#endif
+                auto to_recycle = it.current;
+
+                if (last == it.current)
+                    last = it.prev;
+                it.current = it.current->mNext;
+                if (it.prev)
+                {
+                    it.prev->mNext = it.current;
+                }
+                else
+                {
+                    first = it.current;
+                }
+                if (ISQUEUE)
+                    recycle_node_unsafe(to_recycle);
+                else
+                    delete to_recycle;
+                return it;
+            }
+
+            bool erase(const Delegate* const del)
+            {
+                auto it = begin();
+                while (it)
+                {
+                    if (del == &(*it))
+                    {
+                        erase(it);
+                        return true;
+                    }
+                    ++it;
+                }
+                return false;
+            }
+
+            operator bool() const
+            {
+                return first;
+            }
+
+            R operator()(P... args)
+            {
+                auto it = begin();
+                if (!it)
+                    return {};
+
+                static std::atomic<bool> fence(false);
+                // prevent recursive calls
+#if defined(ARDUINO) && !defined(ESP32)
+                if (fence.load()) return {};
+                fence.store(true);
+#else
+                if (fence.exchange(true)) return {};
+#endif
+
+                R result;
+                do
+                {
+                    result = CallP<Delegate, R, ISQUEUE, P...>::execute(*it, args...);
+                    if (result && ISQUEUE)
+                        it = erase(it);
+                    else
+                        ++it;
+#if defined(ESP8266) || defined(ESP32)
+                    // running callbacks might last too long for watchdog etc.
+                    optimistic_yield(10000);
+#endif
+                } while (it);
+
+                fence.store(false);
+                return result;
+            }
+        };
+
+        template< typename Delegate, typename R = void, bool ISQUEUE = false, size_t QUEUE_CAPACITY = 32>
+        class MultiDelegateImpl : public MultiDelegatePImpl<Delegate, R, ISQUEUE, QUEUE_CAPACITY>
+        {
+        public:
+            using MultiDelegatePImpl<Delegate, R, ISQUEUE, QUEUE_CAPACITY>::MultiDelegatePImpl;
+
+            R operator()()
+            {
+                auto it = this->begin();
+                if (!it)
+                    return {};
+
+                static std::atomic<bool> fence(false);
+                // prevent recursive calls
+#if defined(ARDUINO) && !defined(ESP32)
+                if (fence.load()) return {};
+                fence.store(true);
+#else
+                if (fence.exchange(true)) return {};
+#endif
+
+                R result;
+                do
+                {
+                    result = Call<Delegate, R, ISQUEUE>::execute(*it);
+                    if (result && ISQUEUE)
+                        it = this->erase(it);
+                    else
+                        ++it;
+#if defined(ESP8266) || defined(ESP32)
+                    // running callbacks might last too long for watchdog etc.
+                    optimistic_yield(10000);
+#endif
+                } while (it);
+
+                fence.store(false);
+                return result;
+            }
+        };
+
+        template< typename Delegate, typename R, bool ISQUEUE, size_t QUEUE_CAPACITY, typename... P> class MultiDelegate;
+
+        template< typename Delegate, typename R, bool ISQUEUE, size_t QUEUE_CAPACITY, typename... P>
+        class MultiDelegate<Delegate, R(P...), ISQUEUE, QUEUE_CAPACITY> : public MultiDelegatePImpl<Delegate, R, ISQUEUE, QUEUE_CAPACITY, P...>
+        {
+        public:
+            using MultiDelegatePImpl<Delegate, R, ISQUEUE, QUEUE_CAPACITY, P...>::MultiDelegatePImpl;
+        };
+
+        template< typename Delegate, typename R, bool ISQUEUE, size_t QUEUE_CAPACITY>
+        class MultiDelegate<Delegate, R(), ISQUEUE, QUEUE_CAPACITY> : public MultiDelegateImpl<Delegate, R, ISQUEUE, QUEUE_CAPACITY>
+        {
+        public:
+            using MultiDelegateImpl<Delegate, R, ISQUEUE, QUEUE_CAPACITY>::MultiDelegateImpl;
+        };
+
+        template< typename Delegate, bool ISQUEUE, size_t QUEUE_CAPACITY, typename... P>
+        class MultiDelegate<Delegate, void(P...), ISQUEUE, QUEUE_CAPACITY> : public MultiDelegatePImpl<Delegate, void, ISQUEUE, QUEUE_CAPACITY, P...>
+        {
+        public:
+            using MultiDelegatePImpl<Delegate, void, ISQUEUE, QUEUE_CAPACITY, P...>::MultiDelegatePImpl;
+
+            void operator()(P... args)
+            {
+                auto it = this->begin();
+                if (!it)
+                    return;
+
+                static std::atomic<bool> fence(false);
+                // prevent recursive calls
+#if defined(ARDUINO) && !defined(ESP32)
+                if (fence.load()) return;
+                fence.store(true);
+#else
+                if (fence.exchange(true)) return;
+#endif
+
+                do
+                {
+                    CallP<Delegate, void, ISQUEUE, P...>::execute(*it, args...);
+                    if (ISQUEUE)
+                        it = this->erase(it);
+                    else
+                        ++it;
+#if defined(ESP8266) || defined(ESP32)
+                    // running callbacks might last too long for watchdog etc.
+                    optimistic_yield(10000);
+#endif
+                } while (it);
+
+                fence.store(false);
+            }
+        };
+
+        template< typename Delegate, bool ISQUEUE, size_t QUEUE_CAPACITY>
+        class MultiDelegate<Delegate, void(), ISQUEUE, QUEUE_CAPACITY> : public MultiDelegateImpl<Delegate, void, ISQUEUE, QUEUE_CAPACITY>
+        {
+        public:
+            using MultiDelegateImpl<Delegate, void, ISQUEUE, QUEUE_CAPACITY>::MultiDelegateImpl;
+
+            void operator()()
+            {
+                auto it = this->begin();
+                if (!it)
+                    return;
+
+                static std::atomic<bool> fence(false);
+                // prevent recursive calls
+#if defined(ARDUINO) && !defined(ESP32)
+                if (fence.load()) return;
+                fence.store(true);
+#else
+                if (fence.exchange(true)) return;
+#endif
+
+                do
+                {
+                    Call<Delegate, void, ISQUEUE>::execute(*it);
+                    if (ISQUEUE)
+                        it = this->erase(it);
+                    else
+                        ++it;
+#if defined(ESP8266) || defined(ESP32)
+                    // running callbacks might last too long for watchdog etc.
+                    optimistic_yield(10000);
+#endif
+                } while (it);
+
+                fence.store(false);
+            }
+        };
+
+    }
+
+}
+
+/**
+The MultiDelegate class template can be specialized to either a queue or an event multiplexer.
+It is designed to be used with Delegate, the efficient runtime wrapper for C function ptr and C++ std::function.
+@tparam Delegate specifies the concrete type that MultiDelegate bases the queue or event multiplexer on.
+@tparam ISQUEUE modifies the generated MultiDelegate class in subtle ways. In queue mode (ISQUEUE == true),
+               the value of QUEUE_CAPACITY enforces the maximum number of simultaneous items the queue can contain.
+               This is exploited to minimize the use of new and delete by reusing already allocated items, thus
+               reducing heap fragmentation. In event multiplexer mode (ISQUEUE = false), new and delete are
+               used for allocation of the event handler items.
+               If the result type of the function call operator of Delegate is void, calling a MultiDelegate queue
+               removes each item after calling it; a Multidelegate event multiplexer keeps event handlers until
+               explicitly removed.
+               If the result type of the function call operator of Delegate is non-void, in a MultiDelegate queue
+               the type-conversion to bool of that result determines if the item is immediately removed or kept
+               after each call: if true is returned, the item is removed. A Multidelegate event multiplexer keeps event
+               handlers until they are explicitly removed.
+@tparam QUEUE_CAPACITY is only used if ISQUEUE == true. Then, it sets the maximum capacity that the queue dynamically
+               allocates from the heap. Unused items are not returned to the heap, but are managed by the MultiDelegate
+               instance during its own lifetime for efficiency.
+*/
+template< typename Delegate, bool ISQUEUE = false, size_t QUEUE_CAPACITY = 32>
+class MultiDelegate : public delegate::detail::MultiDelegate<Delegate, typename Delegate::target_type, ISQUEUE, QUEUE_CAPACITY>
+{
+public:
+    using delegate::detail::MultiDelegate<Delegate, typename Delegate::target_type, ISQUEUE, QUEUE_CAPACITY>::MultiDelegate;
+};
+
+#endif // __MULTIDELEGATE_H

src/EspSoftwareSerial/src/circular_queue/circular_queue.h

@@ -0,0 +1,384 @@
+/*
+circular_queue.h - Implementation of a lock-free circular queue for EspSoftwareSerial.
+Copyright (c) 2019 Dirk O. Kaar. All rights reserved.
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#ifndef __circular_queue_h
+#define __circular_queue_h
+
+#ifdef ARDUINO
+#include <Arduino.h>
+#endif
+
+#if defined(ESP8266) || defined(ESP32) || !defined(ARDUINO)
+#include <atomic>
+#include <memory>
+#include <algorithm>
+#include "Delegate.h"
+using std::min;
+#else
+#include "ghostl.h"
+#endif
+
+#if !defined(ESP32) && !defined(ESP8266)
+#define IRAM_ATTR
+#endif
+
+#if defined(__GNUC__)
+#undef ALWAYS_INLINE_ATTR
+#define ALWAYS_INLINE_ATTR __attribute__((always_inline))
+#else
+#define ALWAYS_INLINE_ATTR
+#endif
+
+/*!
+    @brief	Instance class for a single-producer, single-consumer circular queue / ring buffer (FIFO).
+            This implementation is lock-free between producer and consumer for the available(), peek(),
+            pop(), and push() type functions.
+*/
+template< typename T, typename ForEachArg = void >
+class circular_queue
+{
+public:
+    /*!
+        @brief	Constructs a valid, but zero-capacity dummy queue.
+    */
+    circular_queue() : m_bufSize(1)
+    {
+        m_inPos.store(0);
+        m_outPos.store(0);
+    }
+    /*!
+        @brief  Constructs a queue of the given maximum capacity.
+    */
+    circular_queue(const size_t capacity) : m_bufSize(capacity + 1), m_buffer(new T[m_bufSize])
+    {
+        m_inPos.store(0);
+        m_outPos.store(0);
+    }
+    circular_queue(circular_queue&& cq) :
+        m_bufSize(cq.m_bufSize), m_buffer(cq.m_buffer), m_inPos(cq.m_inPos.load()), m_outPos(cq.m_outPos.load())
+    {}
+    ~circular_queue()
+    {
+        m_buffer.reset();
+    }
+    circular_queue(const circular_queue&) = delete;
+    circular_queue& operator=(circular_queue&& cq)
+    {
+        m_bufSize = cq.m_bufSize;
+        m_buffer = cq.m_buffer;
+        m_inPos.store(cq.m_inPos.load());
+        m_outPos.store(cq.m_outPos.load());
+    }
+    circular_queue& operator=(const circular_queue&) = delete;
+
+    /*!
+        @brief	Get the numer of elements the queue can hold at most.
+    */
+    size_t capacity() const
+    {
+        return m_bufSize - 1;
+    }
+
+    /*!
+        @brief	Resize the queue. The available elements in the queue are preserved.
+                This is not lock-free and concurrent producer or consumer access
+                will lead to corruption.
+        @return True if the new capacity could accommodate the present elements in
+                the queue, otherwise nothing is done and false is returned.
+    */
+    bool capacity(const size_t cap);
+
+    /*!
+        @brief	Discard all data in the queue.
+    */
+    void flush()
+    {
+        m_outPos.store(m_inPos.load());
+    }
+
+    /*!
+        @brief	Get a snapshot number of elements that can be retrieved by pop.
+    */
+    size_t IRAM_ATTR available() const
+    {
+        int avail = static_cast<int>(m_inPos.load() - m_outPos.load());
+        if (avail < 0) avail += m_bufSize;
+        return avail;
+    }
+
+    /*!
+        @brief	Get the remaining free elementes for pushing.
+    */
+    size_t IRAM_ATTR available_for_push() const
+    {
+        int avail = static_cast<int>(m_outPos.load() - m_inPos.load()) - 1;
+        if (avail < 0) avail += m_bufSize;
+        return avail;
+    }
+
+    /*!
+        @brief	Peek at the next element pop will return without removing it from the queue.
+        @return An rvalue copy of the next element that can be popped. If the queue is empty,
+                return an rvalue copy of the element that is pending the next push.
+    */
+    T peek() const
+    {
+        const auto outPos = m_outPos.load(std::memory_order_relaxed);
+        std::atomic_thread_fence(std::memory_order_acquire);
+        return m_buffer[outPos];
+    }
+
+    /*!
+        @brief	Peek at the next pending input value.
+        @return A reference to the next element that can be pushed.
+    */
+    T& IRAM_ATTR pushpeek()
+    {
+        const auto inPos = m_inPos.load(std::memory_order_relaxed);
+        std::atomic_thread_fence(std::memory_order_acquire);
+        return m_buffer[inPos];
+    }
+
+    /*!
+        @brief	Release the next pending input value, accessible by pushpeek(), into the queue.
+        @return true if the queue accepted the value, false if the queue
+                was full.
+    */
+    bool IRAM_ATTR push()
+    {
+        const auto inPos = m_inPos.load(std::memory_order_acquire);
+        const size_t next = (inPos + 1) % m_bufSize;
+        if (next == m_outPos.load(std::memory_order_relaxed)) {
+            return false;
+        }
+        std::atomic_thread_fence(std::memory_order_release);
+        m_inPos.store(next, std::memory_order_release);
+        return true;
+    }
+
+    /*!
+        @brief	Move the rvalue parameter into the queue.
+        @return true if the queue accepted the value, false if the queue
+                was full.
+    */
+    bool IRAM_ATTR push(T&& val)
+    {
+        const auto inPos = m_inPos.load(std::memory_order_acquire);
+        const size_t next = (inPos + 1) % m_bufSize;
+        if (next == m_outPos.load(std::memory_order_relaxed)) {
+            return false;
+        }
+        m_buffer[inPos] = std::move(val);
+        std::atomic_thread_fence(std::memory_order_release);
+        m_inPos.store(next, std::memory_order_release);
+        return true;
+    }
+
+    /*!
+        @brief	Push a copy of the parameter into the queue.
+        @return true if the queue accepted the value, false if the queue
+                was full.
+    */
+    inline bool IRAM_ATTR push(const T& val) ALWAYS_INLINE_ATTR
+    {
+        T v(val);
+        return push(std::move(v));
+    }
+
+#if defined(ESP8266) || defined(ESP32) || !defined(ARDUINO)
+    /*!
+        @brief	Push copies of multiple elements from a buffer into the queue,
+                in order, beginning at buffer's head.
+        @return The number of elements actually copied into the queue, counted
+                from the buffer head.
+    */
+    size_t push_n(const T* buffer, size_t size);
+#endif
+
+    /*!
+        @brief	Pop the next available element from the queue.
+        @return An rvalue copy of the popped element, or a default
+                value of type T if the queue is empty.
+    */
+    T pop();
+
+#if defined(ESP8266) || defined(ESP32) || !defined(ARDUINO)
+    /*!
+        @brief	Pop multiple elements in ordered sequence from the queue to a buffer.
+                If buffer is nullptr, simply discards up to size elements from the queue.
+        @return The number of elements actually popped from the queue to
+                buffer.
+    */
+    size_t pop_n(T* buffer, size_t size);
+#endif
+
+    /*!
+        @brief	Iterate over and remove each available element from queue,
+                calling back fun with an rvalue reference of every single element.
+    */
+#if defined(ESP8266) || defined(ESP32) || !defined(ARDUINO)
+    void for_each(const Delegate<void(T&&), ForEachArg>& fun);
+#else
+    void for_each(Delegate<void(T&&), ForEachArg> fun);
+#endif
+
+    /*!
+        @brief	In reverse order, iterate over, pop and optionally requeue each available element from the queue,
+                calling back fun with a reference of every single element.
+                Requeuing is dependent on the return boolean of the callback function. If it
+                returns true, the requeue occurs.
+    */
+#if defined(ESP8266) || defined(ESP32) || !defined(ARDUINO)
+    bool for_each_rev_requeue(const Delegate<bool(T&), ForEachArg>& fun);
+#else
+    bool for_each_rev_requeue(Delegate<bool(T&), ForEachArg> fun);
+#endif
+
+protected:
+    size_t m_bufSize;
+#if defined(ESP8266) || defined(ESP32) || !defined(ARDUINO)
+    std::unique_ptr<T[]> m_buffer;
+#else
+    std::unique_ptr<T> m_buffer;
+#endif
+    std::atomic<size_t> m_inPos;
+    std::atomic<size_t> m_outPos;
+};
+
+template< typename T, typename ForEachArg >
+bool circular_queue<T, ForEachArg>::capacity(const size_t cap)
+{
+    if (cap + 1 == m_bufSize) return true;
+    else if (available() > cap) return false;
+    std::unique_ptr<T[] > buffer(new T[cap + 1]);
+    const auto available = pop_n(buffer, cap);
+    m_buffer.reset(buffer);
+    m_bufSize = cap + 1;
+    m_inPos.store(available, std::memory_order_relaxed);
+    m_outPos.store(0, std::memory_order_relaxed);
+    return true;
+}
+
+#if defined(ESP8266) || defined(ESP32) || !defined(ARDUINO)
+template< typename T, typename ForEachArg >
+size_t circular_queue<T, ForEachArg>::push_n(const T* buffer, size_t size)
+{
+    const auto inPos = m_inPos.load(std::memory_order_acquire);
+    const auto outPos = m_outPos.load(std::memory_order_relaxed);
+
+    size_t blockSize = (outPos > inPos) ? outPos - 1 - inPos : (outPos == 0) ? m_bufSize - 1 - inPos : m_bufSize - inPos;
+    blockSize = min(size, blockSize);
+    if (!blockSize) return 0;
+    int next = (inPos + blockSize) % m_bufSize;
+
+    auto dest = m_buffer.get() + inPos;
+    std::copy_n(std::make_move_iterator(buffer), blockSize, dest);
+    size = min(size - blockSize, outPos > 1 ? static_cast<size_t>(outPos - next - 1) : 0);
+    next += size;
+    dest = m_buffer.get();
+    std::copy_n(std::make_move_iterator(buffer + blockSize), size, dest);
+
+    std::atomic_thread_fence(std::memory_order_release);
+    m_inPos.store(next, std::memory_order_release);
+    return blockSize + size;
+}
+#endif
+
+template< typename T, typename ForEachArg >
+T circular_queue<T, ForEachArg>::pop()
+{
+    const auto outPos = m_outPos.load(std::memory_order_acquire);
+    if (m_inPos.load(std::memory_order_relaxed) == outPos) return {};
+
+    std::atomic_thread_fence(std::memory_order_acquire);
+
+    auto val = std::move(m_buffer[outPos]);
+
+    m_outPos.store((outPos + 1) % m_bufSize, std::memory_order_release);
+    return val;
+}
+
+#if defined(ESP8266) || defined(ESP32) || !defined(ARDUINO)
+template< typename T, typename ForEachArg >
+size_t circular_queue<T, ForEachArg>::pop_n(T* buffer, size_t size) {
+    size_t avail = size = min(size, available());
+    if (!avail) return 0;
+    const auto outPos = m_outPos.load(std::memory_order_acquire);
+    size_t n = min(avail, static_cast<size_t>(m_bufSize - outPos));
+
+    std::atomic_thread_fence(std::memory_order_acquire);
+
+    if (buffer) {
+        buffer = std::copy_n(std::make_move_iterator(m_buffer.get() + outPos), n, buffer);
+        avail -= n;
+        std::copy_n(std::make_move_iterator(m_buffer.get()), avail, buffer);
+    }
+
+    m_outPos.store((outPos + size) % m_bufSize, std::memory_order_release);
+    return size;
+}
+#endif
+
+template< typename T, typename ForEachArg >
+#if defined(ESP8266) || defined(ESP32) || !defined(ARDUINO)
+void circular_queue<T, ForEachArg>::for_each(const Delegate<void(T&&), ForEachArg>& fun)
+#else
+void circular_queue<T, ForEachArg>::for_each(Delegate<void(T&&), ForEachArg> fun)
+#endif
+{
+    auto outPos = m_outPos.load(std::memory_order_acquire);
+    const auto inPos = m_inPos.load(std::memory_order_relaxed);
+    std::atomic_thread_fence(std::memory_order_acquire);
+    while (outPos != inPos)
+    {
+        fun(std::move(m_buffer[outPos]));
+        outPos = (outPos + 1) % m_bufSize;
+        m_outPos.store(outPos, std::memory_order_release);
+    }
+}
+
+template< typename T, typename ForEachArg >
+#if defined(ESP8266) || defined(ESP32) || !defined(ARDUINO)
+bool circular_queue<T, ForEachArg>::for_each_rev_requeue(const Delegate<bool(T&), ForEachArg>& fun)
+#else
+bool circular_queue<T, ForEachArg>::for_each_rev_requeue(Delegate<bool(T&), ForEachArg> fun)
+#endif
+{
+    auto inPos0 = circular_queue<T, ForEachArg>::m_inPos.load(std::memory_order_acquire);
+    auto outPos = circular_queue<T, ForEachArg>::m_outPos.load(std::memory_order_relaxed);
+    if (outPos == inPos0) return false;
+    auto pos = inPos0;
+    auto outPos1 = inPos0;
+    const auto posDecr = circular_queue<T, ForEachArg>::m_bufSize - 1;
+    std::atomic_thread_fence(std::memory_order_acquire);
+    do {
+        pos = (pos + posDecr) % circular_queue<T, ForEachArg>::m_bufSize;
+        T&& val = std::move(circular_queue<T, ForEachArg>::m_buffer[pos]);
+        if (fun(val))
+        {
+            outPos1 = (outPos1 + posDecr) % circular_queue<T, ForEachArg>::m_bufSize;
+            if (outPos1 != pos) circular_queue<T, ForEachArg>::m_buffer[outPos1] = std::move(val);
+        }
+    } while (pos != outPos);
+    std::atomic_thread_fence(std::memory_order_release);
+    circular_queue<T, ForEachArg>::m_outPos.store(outPos1, std::memory_order_release);
+    return true;
+}
+
+#endif // __circular_queue_h

src/EspSoftwareSerial/src/circular_queue/circular_queue_mp.h

@@ -0,0 +1,310 @@
+/*
+circular_queue_mp.h - Implementation of a lock-free circular queue for EspSoftwareSerial.
+Copyright (c) 2019 Dirk O. Kaar. All rights reserved.
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#ifndef __circular_queue_mp_h
+#define __circular_queue_mp_h
+
+#include "circular_queue.h"
+
+#if defined(ESP8266)
+#include <interrupts.h>
+using esp8266::InterruptLock;
+#endif
+
+/*!
+    @brief	Instance class for a multi-producer, single-consumer circular queue / ring buffer (FIFO).
+            This implementation is lock-free between producers and consumer for the available(), peek(),
+            pop(), and push() type functions.
+*/
+template< typename T, typename ForEachArg = void >
+class circular_queue_mp : protected circular_queue<T, ForEachArg>
+{
+public:
+    circular_queue_mp() : circular_queue<T, ForEachArg>()
+    {
+        m_inPos_mp.store(0);
+        m_concurrent_mp.store(0);
+    }
+    circular_queue_mp(const size_t capacity) : circular_queue<T, ForEachArg>(capacity)
+    {
+        m_inPos_mp.store(0);
+        m_concurrent_mp.store(0);
+    }
+    circular_queue_mp(circular_queue_mp<T, ForEachArg>&& cq) : circular_queue<T, ForEachArg>(std::move(cq))
+    {
+        m_inPos_mp.store(cq.m_inPos_mp.load());
+        m_concurrent_mp.store(cq.m_concurrent_mp.load());
+    }
+    circular_queue_mp& operator=(circular_queue_mp&& cq)
+    {
+        circular_queue<T, ForEachArg>::operator=(std::move(cq));
+        m_inPos_mp.store(cq.m_inPos_mp.load());
+        m_concurrent_mp.store(cq.m_concurrent_mp.load());
+    }
+    circular_queue_mp& operator=(const circular_queue_mp&) = delete;
+
+    using circular_queue<T, ForEachArg>::capacity;
+    using circular_queue<T, ForEachArg>::flush;
+    using circular_queue<T, ForEachArg>::peek;
+    using circular_queue<T, ForEachArg>::pop;
+    using circular_queue<T, ForEachArg>::pop_n;
+    using circular_queue<T, ForEachArg>::for_each;
+    using circular_queue<T, ForEachArg>::for_each_rev_requeue;
+
+    T& pushpeek() = delete;
+    bool push() = delete;
+
+    inline size_t IRAM_ATTR available() const ALWAYS_INLINE_ATTR
+    {
+        return circular_queue<T, ForEachArg>::available();
+    }
+    inline size_t IRAM_ATTR available_for_push() const ALWAYS_INLINE_ATTR
+    {
+        return circular_queue<T, ForEachArg>::available_for_push();
+    }
+
+    /*!
+        @brief	Resize the queue. The available elements in the queue are preserved.
+                This is not lock-free and concurrent producer or consumer access
+                will lead to corruption.
+        @return True if the new capacity could accommodate the present elements in
+                the queue, otherwise nothing is done and false is returned.
+    */
+    bool capacity(const size_t cap);
+
+    /*!
+        @brief	Move the rvalue parameter into the queue, guarded
+                for multiple concurrent producers.
+        @return true if the queue accepted the value, false if the queue
+                was full.
+    */
+    bool push(T&& val);
+
+    /*!
+        @brief	Push a copy of the parameter into the queue, guarded
+                for multiple concurrent producers.
+        @return true if the queue accepted the value, false if the queue
+                was full.
+    */
+    inline bool IRAM_ATTR push(const T& val) ALWAYS_INLINE_ATTR
+    {
+        T v(val);
+        return push(std::move(v));
+    }
+
+    /*!
+        @brief	Push copies of multiple elements from a buffer into the queue,
+                in order, beginning at buffer's head. This is safe for
+                multiple producers.
+        @return The number of elements actually copied into the queue, counted
+                from the buffer head.
+    */
+#if defined(ESP8266) || defined(ESP32) || !defined(ARDUINO)
+    size_t push_n(const T* buffer, size_t size);
+#endif
+
+protected:
+    std::atomic<size_t> m_inPos_mp;
+    std::atomic<int> m_concurrent_mp;
+};
+
+template< typename T, typename ForEachArg >
+bool circular_queue_mp<T, ForEachArg>::capacity(const size_t cap)
+{
+    if (cap + 1 == circular_queue<T, ForEachArg>::m_bufSize) return true;
+    else if (!circular_queue<T, ForEachArg>::capacity(cap)) return false;
+    m_inPos_mp.store(circular_queue<T, ForEachArg>::m_inPos.load(std::memory_order_relaxed),
+        std::memory_order_relaxed);
+    m_concurrent_mp.store(0, std::memory_order_relaxed);
+    return true;
+}
+
+template< typename T, typename ForEachArg >
+bool IRAM_ATTR circular_queue_mp<T, ForEachArg>::push(T&& val)
+{
+    size_t inPos_mp;
+    size_t next;
+#if !defined(ESP32) && defined(ARDUINO)
+    class InterruptLock {
+    public:
+        InterruptLock() {
+            noInterrupts();
+        }
+        ~InterruptLock() {
+            interrupts();
+        }
+    };
+    {
+        InterruptLock lock;
+#else
+    ++m_concurrent_mp;
+    do
+    {
+#endif
+        inPos_mp = m_inPos_mp.load(std::memory_order_relaxed);
+        next = (inPos_mp + 1) % circular_queue<T, ForEachArg>::m_bufSize;
+        if (next == circular_queue<T, ForEachArg>::m_outPos.load(std::memory_order_relaxed)) {
+#if !defined(ESP32) && defined(ARDUINO)
+            return false;
+        }
+        m_inPos_mp.store(next, std::memory_order_relaxed);
+        m_concurrent_mp.store(m_concurrent_mp.load(std::memory_order_relaxed) + 1,
+            std::memory_order_relaxed);
+        std::atomic_thread_fence(std::memory_order_release);
+    }
+#else
+            int concurrent_mp;
+            do
+            {
+                inPos_mp = m_inPos_mp.load();
+                concurrent_mp = m_concurrent_mp.load();
+                if (1 == concurrent_mp)
+                {
+                    circular_queue<T, ForEachArg>::m_inPos.store(inPos_mp, std::memory_order_release);
+                }
+            }
+            while (!m_concurrent_mp.compare_exchange_weak(concurrent_mp, concurrent_mp - 1));
+            return false;
+        }
+    }
+    while (!m_inPos_mp.compare_exchange_weak(inPos_mp, next));
+#endif
+
+    circular_queue<T, ForEachArg>::m_buffer[inPos_mp] = std::move(val);
+
+    std::atomic_thread_fence(std::memory_order_release);
+
+#if !defined(ESP32) && defined(ARDUINO)
+    {
+        InterruptLock lock;
+        if (1 == m_concurrent_mp.load(std::memory_order_relaxed))
+        {
+            inPos_mp = m_inPos_mp.load(std::memory_order_relaxed);
+            circular_queue<T, ForEachArg>::m_inPos.store(inPos_mp, std::memory_order_relaxed);
+        }
+        m_concurrent_mp.store(m_concurrent_mp.load(std::memory_order_relaxed) - 1,
+            std::memory_order_relaxed);
+        std::atomic_thread_fence(std::memory_order_release);
+    }
+#else
+    int concurrent_mp;
+    do
+    {
+        inPos_mp = m_inPos_mp.load();
+        concurrent_mp = m_concurrent_mp.load();
+        if (1 == concurrent_mp)
+        {
+            circular_queue<T, ForEachArg>::m_inPos.store(inPos_mp, std::memory_order_release);
+        }
+    }
+    while (!m_concurrent_mp.compare_exchange_weak(concurrent_mp, concurrent_mp - 1));
+#endif
+
+    return true;
+}
+
+#if defined(ESP8266) || defined(ESP32) || !defined(ARDUINO)
+template< typename T, typename ForEachArg >
+size_t circular_queue_mp<T, ForEachArg>::push_n(const T* buffer, size_t size)
+{
+    const auto outPos = circular_queue<T, ForEachArg>::m_outPos.load(std::memory_order_relaxed);
+    size_t inPos_mp;
+    size_t next;
+    size_t blockSize;
+#if !defined(ESP32) && defined(ARDUINO)
+    {
+        InterruptLock lock;
+#else
+    ++m_concurrent_mp;
+    do
+    {
+#endif
+        inPos_mp = m_inPos_mp.load(std::memory_order_relaxed);
+        blockSize = (outPos > inPos_mp) ? outPos - 1 - inPos_mp : (outPos == 0) ? circular_queue<T, ForEachArg>::m_bufSize - 1 - inPos_mp : circular_queue<T, ForEachArg>::m_bufSize - inPos_mp;
+        blockSize = min(size, blockSize);
+        if (!blockSize)
+        {
+#if !defined(ESP32) && defined(ARDUINO)
+            return 0;
+        }
+        next = (inPos_mp + blockSize) % circular_queue<T, ForEachArg>::m_bufSize;
+        m_inPos_mp.store(next, std::memory_order_relaxed);
+        m_concurrent_mp.store(m_concurrent_mp.load(std::memory_order_relaxed) + 1,
+            std::memory_order_relaxed);
+        std::atomic_thread_fence(std::memory_order_release);
+    }
+#else
+            int concurrent_mp = m_concurrent_mp.load();
+            do
+            {
+                inPos_mp = m_inPos_mp.load();
+                concurrent_mp = m_concurrent_mp.load();
+                if (1 == concurrent_mp)
+                {
+                    circular_queue<T, ForEachArg>::m_inPos.store(inPos_mp, std::memory_order_release);
+                }
+            }
+            while (!m_concurrent_mp.compare_exchange_weak(concurrent_mp, concurrent_mp - 1));
+            return false;
+        }
+    }
+    while (!m_inPos_mp.compare_exchange_weak(inPos_mp, next));
+#endif
+
+    auto dest = circular_queue<T, ForEachArg>::m_buffer.get() + inPos_mp;
+    std::copy_n(std::make_move_iterator(buffer), blockSize, dest);
+    size = min(size - blockSize, outPos > 1 ? static_cast<size_t>(outPos - next - 1) : 0);
+    next += size;
+    dest = circular_queue<T, ForEachArg>::m_buffer.get();
+    std::copy_n(std::make_move_iterator(buffer + blockSize), size, dest);
+
+    std::atomic_thread_fence(std::memory_order_release);
+
+#if !defined(ESP32) && defined(ARDUINO)
+    {
+        InterruptLock lock;
+        if (1 == m_concurrent_mp.load(std::memory_order_relaxed))
+        {
+            inPos_mp = m_inPos_mp.load(std::memory_order_relaxed);
+            circular_queue<T, ForEachArg>::m_inPos.store(inPos_mp, std::memory_order_relaxed);
+        }
+        m_concurrent_mp.store(m_concurrent_mp.load(std::memory_order_relaxed) - 1,
+            std::memory_order_relaxed);
+        std::atomic_thread_fence(std::memory_order_release);
+    }
+#else
+    int concurrent_mp;
+    do
+    {
+        inPos_mp = m_inPos_mp.load();
+        concurrent_mp = m_concurrent_mp.load();
+        if (1 == concurrent_mp)
+        {
+            circular_queue<T, ForEachArg>::m_inPos.store(inPos_mp, std::memory_order_release);
+        }
+    }
+    while (!m_concurrent_mp.compare_exchange_weak(concurrent_mp, concurrent_mp - 1));
+#endif
+
+    return blockSize + size;
+}
+
+#endif
+
+#endif // __circular_queue_mp_h

src/EspSoftwareSerial/src/circular_queue/ghostl.h

@@ -0,0 +1,94 @@
+/*
+ghostl.h - Implementation of a bare-bones, mostly no-op, C++ STL shell
+           that allows building some Arduino ESP8266/ESP32
+           libraries on Aruduino AVR.
+Copyright (c) 2019 Dirk O. Kaar. All rights reserved.
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#ifndef __ghostl_h
+#define __ghostl_h
+
+#if defined(ARDUINO_ARCH_SAMD)
+#include <atomic>
+#endif
+
+using size_t = decltype(sizeof(char));
+
+namespace std
+{
+#if !defined(ARDUINO_ARCH_SAMD)
+    typedef enum memory_order {
+        memory_order_relaxed,
+        memory_order_acquire,
+        memory_order_release,
+        memory_order_seq_cst
+    } memory_order;
+    template< typename T > class atomic {
+    private:
+        T value;
+    public:
+        atomic() {}
+        atomic(T desired) { value = desired; }
+        void store(T desired, std::memory_order = std::memory_order_seq_cst) volatile noexcept { value = desired; }
+        T load(std::memory_order = std::memory_order_seq_cst) const volatile noexcept { return value; }
+    };
+    inline void atomic_thread_fence(std::memory_order order) noexcept {}
+    template< typename T > T&& move(T& t) noexcept { return static_cast<T&&>(t); }
+#endif
+
+    template< typename T, size_t long N > struct array
+    {
+        T _M_elems[N];
+        decltype(sizeof(0)) size() const { return N; }
+        T& operator[](decltype(sizeof(0)) i) { return _M_elems[i]; }
+        const T& operator[](decltype(sizeof(0)) i) const { return _M_elems[i]; }
+    };
+
+    template< typename T > class unique_ptr
+    {
+    public:
+        using pointer = T*;
+        unique_ptr() noexcept : ptr(nullptr) {}
+        unique_ptr(pointer p) : ptr(p) {}
+        pointer operator->() const noexcept { return ptr; }
+        T& operator[](decltype(sizeof(0)) i) const { return ptr[i]; }
+        void reset(pointer p = pointer()) noexcept
+        {
+            delete ptr;
+            ptr = p;
+        }
+        T& operator*() const { return *ptr; }
+    private:
+        pointer ptr;
+    };
+
+    template< typename T > using function = T*;
+    using nullptr_t = decltype(nullptr);
+
+    template<typename T>
+    struct identity {
+        typedef T type;
+    };
+
+    template <typename T>
+    inline T&& forward(typename identity<T>::type& t) noexcept
+    {
+        return static_cast<typename identity<T>::type&&>(t);
+    }
+}
+
+#endif // __ghostl_h

src/Software/assets/external_comps/cn.kevinkun.BingMap/assets/bingmap.html

@@ -0,0 +1,489 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <title></title>
+    <meta charset="utf-8" />
+	<meta content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0" name="viewport" />
+	<style>
+	*{
+		margin:0px;
+		padding:0px;
+	}
+	#myMap{
+		position:absolute;
+		width:100%;
+		height:100%;
+	}	
+</style>
+<!--
+<style>
+	.bm_bottomLeftOverlay{
+			display:none !important
+		}
+	</style>
+
+-->
+
+    <script type='text/javascript'>
+	var map;
+	var infobox;
+	var key;
+	var zoom = 15;
+	var center =[39.92, 116.40];
+	var disablePanning = false;
+	var disableZooming = false;
+	var maxZoom = 17;
+	var minZoom = 5;
+	var showLocateMeButton = true;
+	var showMapTypeSelector= true;
+	var showScalebar= true;
+	var showZoomButtons =true;
+	var mapType = "road";
+	
+	function GetMap() {
+		map = new Microsoft.Maps.Map('#myMap', {
+			//credentials: 'AmxEDXs-Yhwj3Uv5WvVB4Q6YvISdMjqrC-pPOw0rNKMu_5rrksVmAJkpcv5HJwJS',
+			zoom: zoom,
+			showDashboard: true,
+			showLocateMeButton:showLocateMeButton,
+			showMapTypeSelector:showMapTypeSelector,
+			showTermsLink: false,
+			//enableHighDpi:true,
+			enableClickableLogo: false,
+			//mapTypeId: Microsoft.Maps.MapTypeId.aerial,
+			//mapTypeId: Microsoft.Maps.MapTypeId.road,
+			maxZoom: maxZoom,
+			minZoom: minZoom,
+			disablePanning:disablePanning,
+			disableZooming:disableZooming,
+			//customMapStyle: myStyle,
+			liteMode: true,
+			showScalebar: showScalebar,
+			showZoomButtons: showZoomButtons,
+			center:realLocation(center),
+		});
+		setMapType(mapType);
+
+		infobox = new Microsoft.Maps.Infobox(map.getCenter(), {
+			visible: false,
+		});
+		infobox.setMap(map);
+
+		Microsoft.Maps.Events.addHandler(map, 'click', function(e) {
+
+			if (typeof(KevinkunBingMap) != "undefined") {
+				KevinkunBingMap.mapClicked(JSON.stringify([e.location.latitude, e.location.longitude]));
+			}
+			console.log(JSON.stringify([e.location.latitude, e.location.longitude]));
+		});
+
+		Microsoft.Maps.Events.addHandler(map, 'viewchangeend', function(e) {
+
+			if (typeof(KevinkunBingMap) != "undefined") {
+				KevinkunBingMap.mapViewChangedEnd(JSON.stringify([map.getCenter()
+					.latitude, map.getCenter()
+					.longitude
+				]), map.getZoom(), JSON.stringify(map.getBounds()
+					.bounds));
+			}
+			console.log(JSON.stringify([map.getCenter().latitude, 
+										map.getCenter().longitude]), 
+						map.getZoom(), 
+						JSON.stringify(map.getBounds().bounds));
+		});
+	}
+	
+	function setMapType(type) {
+		var mapTypeId;
+		switch (type) {
+		  case 'aerial':
+			mapTypeId = Microsoft.Maps.MapTypeId.aerial;
+			break;
+		  case 'canvasDark':
+			mapTypeId = Microsoft.Maps.MapTypeId.canvasDark;
+			break;
+		  case 'canvasLight':
+			mapTypeId = Microsoft.Maps.MapTypeId.canvasLight;
+			break;
+		 case 'birdseye':
+			mapTypeId = Microsoft.Maps.MapTypeId.birdseye;
+			break;
+		 case 'grayscale':
+			mapTypeId = Microsoft.Maps.MapTypeId.grayscale;
+			break;
+		 case 'streetside':
+			mapTypeId = Microsoft.Maps.MapTypeId.streetside;
+			break;
+		  default:
+			mapTypeId = Microsoft.Maps.MapTypeId.road;
+		}
+		map.setView({
+			mapTypeId: mapTypeId
+		});
+	}
+
+
+	function setZoom(z) {
+		map.setView({
+			zoom: z
+		});
+	}
+
+	function getZoom() {
+		return map.getZoom();
+	}
+
+	function setCenter(location) {
+		map.setView({
+			center: realLocation(location)
+		});
+	}
+
+	function getCenter() {
+		return [map.getCenter()
+			.latitude, map.getCenter()
+			.longitude
+		];
+	}
+
+	//视图的右上角和左下角纬度+经度
+	function getBounds() {
+		return map.getBounds()
+			.bounds;
+	}
+
+	function newPushpin(location, id, options) {
+		//options = {title: title,subTitle: subtitle,text: text, color: 'blue',icon: 'poi-custom.png',anchor: new Microsoft.Maps.Point(12, 39), draggable: draggable, };
+		var pin = new Microsoft.Maps.Pushpin(realLocation(location), options);
+		pin.id = id;
+		map.entities.push(pin);
+		Microsoft.Maps.Events.addHandler(pin, 'click', function(e) {
+
+			if (typeof(KevinkunBingMap) != "undefined") {
+				KevinkunBingMap.pushpinClicked(e.target.id, JSON.stringify([e.location.latitude, e.location.longitude]), JSON.stringify([e.point.x, e.point.y]));
+
+			}
+			console.log(e.target.id, JSON.stringify([e.location.latitude, e.location.longitude]), JSON.stringify([e.point.x, e.point.y]));
+		});
+		Microsoft.Maps.Events.addHandler(pin, 'dragend', function(e) {
+
+			if (typeof(KevinkunBingMap) != "undefined") {
+				KevinkunBingMap.pushpinDragEnd(e.target.id, JSON.stringify([e.location.latitude, e.location.longitude]), JSON.stringify([e.point.x, e.point.y]));
+			}
+			console.log(e.target.id, JSON.stringify([e.location.latitude, e.location.longitude]), JSON.stringify([e.point.x, e.point.y]));
+		});
+	}
+
+
+
+	function realLocation(location) {
+		return new Microsoft.Maps.Location(location[0], location[1]);
+	}
+
+	function newPolyline(locations, id, options) {
+		//options = {	strokeColor: 'red',strokeThickness: 3, strokeDashArray: [10,10] };
+		var bingLocations = [];
+		for (var i = 0; i < locations.length; i++) {
+			bingLocations.push(realLocation(locations[i]));
+		}
+		var polyline = new Microsoft.Maps.Polyline(bingLocations, options);
+		polyline.id = id;
+		map.entities.push(polyline);
+		Microsoft.Maps.Events.addHandler(polyline, 'click', function(e) {
+			if (typeof(KevinkunBingMap) != "undefined") {
+				KevinkunBingMap.polylineClicked(e.target.id, JSON.stringify([e.location.latitude, e.location.longitude]), JSON.stringify([e.point.x, e.point.y]));
+
+			}
+			console.log(e.target.id, JSON.stringify([e.location.latitude, e.location.longitude]), JSON.stringify([e.point.x, e.point.y]));
+		});
+	}
+
+	function setPolylineLocation(locations, id) {
+		var bingLocations = [];
+		for (var i = 0; i < locations.length; i++) {
+			bingLocations.push(realLocation(locations[i]));
+		}
+		for (var i = map.entities.getLength() - 1; i >= 0; i--) {
+			var line = map.entities.get(i);
+			if (line.id == id) {
+				line.setLocations(bingLocations);
+
+			}
+		}
+	}
+
+	function newPolygon(locations, id, options) {
+		//options = { fillColor: '#ff000022', strokeColor: '#00ff00', strokeThickness: 4, strokeDashArray: [10,5] };
+
+		var bingLocations = [];
+		for (var i = 0; i < locations.length; i++) {
+			bingLocations.push(realLocation(locations[i]));
+		}
+		var polygon = new Microsoft.Maps.Polygon(bingLocations, options);
+		polygon.id = id;
+		map.entities.push(polygon);
+		Microsoft.Maps.Events.addHandler(polygon, 'click', function(e) {
+			if (typeof(KevinkunBingMap) != "undefined") {
+				KevinkunBingMap.polygonClicked(e.target.id, JSON.stringify([e.location.latitude, e.location.longitude]), JSON.stringify([e.point.x, e.point.y]));
+
+			}
+			console.log(e.target.id, JSON.stringify([e.location.latitude, e.location.longitude]), JSON.stringify([e.point.x, e.point.y]));
+		});
+
+	}
+
+	function newPolygonRegular(center, distance, sides, id, options, angle) {
+		//options = { fillColor: '#ff000022', strokeColor: '#00ff00', strokeThickness: 4, strokeDashArray: [10,5] };
+		Microsoft.Maps.loadModule('Microsoft.Maps.SpatialMath', function() {
+			var locations = Microsoft.Maps.SpatialMath.getRegularPolygon(realLocation(center), distance, sides, Microsoft.Maps.SpatialMath.DistanceUnits.Kilometers,angle);
+			var polygon = new Microsoft.Maps.Polygon(locations, options);
+			polygon.id = id;
+			map.entities.push(polygon);
+			Microsoft.Maps.Events.addHandler(polygon, 'click', function(e) {
+				if (typeof(KevinkunBingMap) != "undefined") {
+					KevinkunBingMap.polygonClicked(e.target.id, JSON.stringify([e.location.latitude, e.location.longitude]), JSON.stringify([e.point.x, e.point.y]));
+				}
+				console.log(e.target.id, JSON.stringify([e.location.latitude, e.location.longitude]), JSON.stringify([e.point.x, e.point.y]));
+
+			});
+		});
+	}
+
+
+	function showInfobox(location, title, description, actions) {
+
+		var options = {
+			location: realLocation(location),
+			title: title,
+			description: description,
+			//maxWidth: 500,
+			showCloseButton:true,
+			actions: null,
+			visible: true,
+		};
+
+		if (actions instanceof Array && actions.length > 0) {
+			var realActions = [];
+			for (var i = 0; i < actions.length; i++) {
+				var option = {};
+				option.label = actions[i];
+				option.eventHandler = function(e) {
+
+					if (typeof(KevinkunBingMap) != "undefined") {
+						KevinkunBingMap.actionClicked(e.srcElement.innerText);
+
+
+					}
+					console.log(e.srcElement.innerText);
+					//hideInfobox();
+				};
+				realActions.push(option);
+
+			}
+			options.actions = realActions;
+		}
+
+		infobox.setOptions(options);
+	}
+
+	function hideInfobox() {
+		infobox.setOptions({
+			visible: false
+		});
+	}
+
+	var directionsManager;
+
+	function calculateDirections(locations,mode) {
+		Microsoft.Maps.loadModule('Microsoft.Maps.Directions', function() {
+			directionsManager = new Microsoft.Maps.Directions.DirectionsManager(map);
+			// Set Route Mode to driving
+			var routeMode;
+			if (mode == 'walking'){
+				routeMode = Microsoft.Maps.Directions.RouteMode.walking;
+			}else if (mode == 'transit'){
+				routeMode = Microsoft.Maps.Directions.RouteMode.transit;
+			}else if (mode == 'truck'){
+				routeMode = Microsoft.Maps.Directions.RouteMode.truck;
+			}else {
+				routeMode = Microsoft.Maps.Directions.RouteMode.driving;
+			}
+			
+			directionsManager.setRequestOptions({
+				distanceUnit: Microsoft.Maps.Directions.DistanceUnit.km,
+				routeMode: routeMode,
+				//routeDraggable: false,
+			});
+			for (var i = 0; i < locations.length; i++) {
+				var waypoint1 = new Microsoft.Maps.Directions.Waypoint({
+					address: "",
+					location: realLocation(locations[i])
+				});
+				directionsManager.addWaypoint(waypoint1);
+			}
+
+			// Set the element in which the itinerary will be rendered
+			directionsManager.setRenderOptions({ itineraryContainer: document.getElementById('printoutPanel') });
+
+			directionsManager.setRenderOptions({
+				drivingPolylineOptions: {
+					strokeColor: 'lightblue',
+					strokeThickness: 1
+				},
+				waypointPushpinOptions: {
+					title: ''
+				}
+			});
+
+			Microsoft.Maps.Events.addHandler(directionsManager, 'directionsError', directionsError);
+			Microsoft.Maps.Events.addHandler(directionsManager, 'directionsUpdated', directionsUpdated);
+
+			directionsManager.calculateDirections();
+		});
+	}
+
+	function directionsUpdated(e) {
+		console.log(e);
+		//Get the current route index.
+		var routeIdx = directionsManager.getRequestOptions()
+			.routeIndex;
+		var total = e.routeSummary.length;
+
+		//var options = [];
+		//for (var i = 0; i < e.routeSummary.length; i++) {
+			//var option = {};
+			//option.distance = e.route[routeIdx].distance;
+			//option.time = e.routeSummary[routeIdx].time;
+			//option.timeWithTraffic = e.routeSummary[routeIdx].timeWithTraffic;
+			//options.push(option);
+		//}
+
+		if (typeof(KevinkunBingMap) != "undefined") {
+			KevinkunBingMap.directionsUpdated(total, routeIdx+1, JSON.stringify(e.route[routeIdx]));
+		}
+		console.log(total, routeIdx+1, e.route[routeIdx]);
+	}
+
+	function directionsError(e) {
+		if (typeof(KevinkunBingMap) != "undefined") {
+			KevinkunBingMap.directionsError(JSON.stringify(e));
+		}
+		console.log(e);
+	}
+
+	function clearRoute() {
+		directionsManager.clearAll();
+	}
+
+	function remove(id) {
+		for (var i = map.entities.getLength() - 1; i >= 0; i--) {
+			var pin = map.entities.get(i);
+			if (pin.id == id) {
+				map.entities.removeAt(i);
+			}
+		}
+	}
+
+	function removeAll() {
+		map.entities.clear();
+	}
+
+	function getAddress(location) {
+		Microsoft.Maps.loadModule('Microsoft.Maps.Search', function() {
+			var searchManager = new Microsoft.Maps.Search.SearchManager(map);
+			var reverseGeocodeRequestOptions = {
+				location: realLocation(location),
+				callback: function(answer, userData) {
+					var ad = answer.address.formattedAddress;
+					if (typeof(KevinkunBingMap) != "undefined") {
+						KevinkunBingMap.gotAddress(ad);
+					}
+					console.log(ad);
+				}
+			};
+			searchManager.reverseGeocode(reverseGeocodeRequestOptions);
+		});
+	}
+
+	function getLocation(address) {
+		Microsoft.Maps.loadModule('Microsoft.Maps.Search', function() {
+			var searchManager = new Microsoft.Maps.Search.SearchManager(map);
+			var requestOptions = {
+				//bounds: map.getBounds(),
+				where: address,
+				callback: function(answer, userData) {
+
+					var result = [];
+					for (var i = 0; i < answer.results.length; i++) {
+						result.push([answer.results[i].name, [answer.results[i].location.latitude, answer.results[i].location.longitude]]);
+					}
+					if (typeof(KevinkunBingMap) != "undefined") {
+						KevinkunBingMap.gotLocation(JSON.stringify(result));
+					}
+					console.log(result);
+				}
+				
+			};
+			searchManager.geocode(requestOptions);
+		});
+	}
+
+	function getDistance(location1, location2) {
+		Microsoft.Maps.loadModule('Microsoft.Maps.SpatialMath', function() {
+			var dis = Microsoft.Maps.SpatialMath.getDistanceTo(realLocation(location1), realLocation(location2), Microsoft.Maps.SpatialMath.DistanceUnits.Kilometers);
+			if (typeof(KevinkunBingMap) != "undefined") {
+				KevinkunBingMap.gotDistance(dis);
+			}
+			console.log(dis);
+		});
+	}
+
+	function loadJS() {
+		
+		var script = document.createElement('script');
+		script.type = 'text/javascript';
+		script.src = 'http://www.bing.com/api/maps/mapcontrol?callback=GetMap&key=' + key;
+		script.async = true;
+		script.defer = true;
+		document.getElementsByTagName('head')[0].appendChild(script);
+	}
+
+	function getQueryVariable(variable) {
+		var query = window.location.search.substring(1);
+		var vars = query.split("&");
+		for (var i = 0; i < vars.length; i++) {
+			var pair = vars[i].split("=");
+			if (pair[0] == variable) {
+				return pair[1];
+			}
+		}
+		return (false);
+	}
+	var watchId;
+	function startTracking() {
+		
+		watchId = navigator.geolocation.watchPosition(function(position) {
+			var loc = [	position.coords.latitude, position.coords.longitude];
+			if (typeof(KevinkunBingMap) != "undefined") {
+				KevinkunBingMap.locationUpdated(JSON.stringify(loc));
+			}
+			console.log("locationUpdated", loc);
+		});
+	}
+	function stopTracking() {
+        // Cancel the geolocation updates.
+        navigator.geolocation.clearWatch(watchId);
+    }
+	//loadJS(getQueryVariable('key'));
+	//loadJS('AmxEDXs-Yhwj3Uv5WvVB4Q6YvISdMjqrC-pPOw0rNKMu_5rrksVmAJkpcv5HJwJS');
+
+
+    </script>
+	
+
+</head>
+<body>
+	<div id='printoutPanel' style='display:none'></div>
+    <div id='myMap'></div>
+</body>
+</html>

src/Software/assets/external_comps/cn.kevinkun.BingMap/files/component_build_infos.json

@@ -0,0 +1 @@
+[{"permissions":["android.permission.ACCESS_FINE_LOCATION"],"conditionalPermissions":{},"conditionalBroadcastReceivers":{},"libraries":[],"native":[],"broadcastReceiver":[],"assets":["pin3.png","pin2.png","bingmap.html","pin1.png"],"activities":[],"broadcastReceivers":[],"type":"cn.kevinkun.BingMap.BingMap","androidMinSdk":["7"]}]

src/Software/assets/external_comps/com.sunny.tts/components.json

@@ -0,0 +1 @@
+[{"categoryString":"EXTENSION","dateBuilt":"2023-09-21","nonVisible":"true","iconName":"https://res.cloudinary.com/andromedaviewflyvipul/image/upload/c_scale,h_20,w_20/v1571472765/ktvu4bapylsvnykoyhdm.png","methods":[{"deprecated":"false","name":"GetVoicesList","description":"Gets a list of voices in dictionary form","params":[]},{"deprecated":"false","name":"TextToSpeech","description":"Converts text to speech and saves audio file to output path","params":[{"name":"text","type":"text"},{"name":"outputhFile","type":"text"},{"name":"voiceName","type":"text"},{"name":"voiceGender","type":"text"},{"name":"voiceLang","type":"text"}]}],"blockProperties":[{"rw":"write-only","deprecated":"false","name":"ApiKey","description":"Set API key","type":"text"},{"rw":"write-only","deprecated":"false","name":"ResourceRegion","description":"Set resource region","type":"text"}],"helpUrl":"https://sunnythedeveloper.in/microsofttts-convert-text-to-audio-using-microsoft-texttospeech-api/","licenseName":"https://creativecommons.org/licenses/by-sa/4.0/","type":"com.sunny.tts.MicrosoftTTS","androidMinSdk":7,"versionName":"1","version":"4","external":"true","showOnPalette":"true","name":"MicrosoftTTS","helpString":"<p>Extension to convert Text to Speech using Microsoft Text-To-Speech API <br> Developed by Sunny Gupta<\/p>\n","events":[{"deprecated":"false","name":"GotVoicesList","description":"Event raised after gettting voices list. Each list element is a dictionary containing voice information.","params":[{"name":"reponseList","type":"list"}]},{"deprecated":"false","name":"GotError","description":"Event raised when error occurs","params":[{"name":"methodName","type":"text"},{"name":"errorMsg","type":"text"}]},{"deprecated":"false","name":"GotSpeechFile","description":"Event raised when text was successfully converted to audio and file was saved","params":[{"name":"outputFile","type":"text"}]}],"properties":[]}]

src/Software/assets/external_comps/com.sunny.tts/extension.properties

@@ -0,0 +1,2 @@
+type=external
+rush-version=1.2.4

src/Software/assets/external_comps/com.sunny.tts/files/component_build_infos.json

@@ -0,0 +1 @@
+[{"assets":[],"activities":[],"permissions":["android.permission.INTERNET"],"type":"com.sunny.tts.MicrosoftTTS","androidMinSdk":[7]}]

src/Software/src/appinventor/ai_karlzj/ruangong/Screen1.bky.2023-10-23T14_34_53+0800.backup

@@ -0,0 +1,10 @@
+<xml xmlns="http://www.w3.org/1999/xhtml">
+  <block type="component_event" id="Nu],`$R_Zo+h]%t0u=E{" x="undefined" y="undefined">
+    <mutation component_type="Button" instance_name="按钮1" event_name="Click"></mutation>
+    <field name="COMPONENT_SELECTOR">按钮1</field>
+    <statement name="DO">
+      <block type="controls_closeScreen" id="_5tFHD60tzn_~.}x1DrY"></block>
+    </statement>
+  </block>
+  <yacodeblocks ya-version="172" language-version="22"></yacodeblocks>
+</xml>

src/Software/src/appinventor/ai_karlzj/ruangong/Screen1.bky.2023-10-25T15_03_56+0800.backup

@@ -0,0 +1,41 @@
+<xml xmlns="http://www.w3.org/1999/xhtml">
+  <block type="component_set_get" id="D7C,mwN}q=UqZ*a5_PK=" x="-411" y="32">
+    <mutation component_type="Button" set_or_get="get" property_name="Enabled" is_generic="false" instance_name="按钮_避障"></mutation>
+    <field name="COMPONENT_SELECTOR">按钮_避障</field>
+    <field name="PROP">Enabled</field>
+  </block>
+  <block type="component_event" id="1E~cny;xyoBW`6/m=u_i" x="-415" y="87">
+    <mutation component_type="Button" instance_name="按钮_实时定位" event_name="Click"></mutation>
+    <field name="COMPONENT_SELECTOR">按钮_实时定位</field>
+    <statement name="DO">
+      <block type="controls_openAnotherScreen" id="$]%v|uY7Rfv~rk!)@z(3">
+        <value name="SCREEN">
+          <block type="text" id=".gh[SARAdd)M$4]M~[y%">
+            <field name="TEXT">dingwei</field>
+          </block>
+        </value>
+      </block>
+    </statement>
+  </block>
+  <block type="component_event" id="20%u[R^-3+ouiy8=/CZF" x="-420" y="187">
+    <mutation component_type="Button" instance_name="按钮_拨打电话" event_name="Click"></mutation>
+    <field name="COMPONENT_SELECTOR">按钮_拨打电话</field>
+    <statement name="DO">
+      <block type="controls_openAnotherScreen" id="JMzPot8U;!E~]~U4SNd+">
+        <value name="SCREEN">
+          <block type="text" id="rD6.uP~:nv;itN019[.z">
+            <field name="TEXT">calling</field>
+          </block>
+        </value>
+      </block>
+    </statement>
+  </block>
+  <block type="component_event" id="7H89A@N/?oES:zQX.*:v" x="-411" y="296">
+    <mutation component_type="Button" instance_name="按钮_关闭" event_name="Click"></mutation>
+    <field name="COMPONENT_SELECTOR">按钮_关闭</field>
+    <statement name="DO">
+      <block type="controls_closeScreen" id="r1-697xyD#}ga{a..=0l"></block>
+    </statement>
+  </block>
+  <yacodeblocks ya-version="172" language-version="22"></yacodeblocks>
+</xml>

src/Software/src/appinventor/ai_karlzj/ruangong/Screen1.scm

@@ -0,0 +1,4 @@
+#|
+$JSON
+{"authURL":["app.gzjkw.net","ai2.appinventor.mit.edu"],"YaVersion":"224","Source":"Form","Properties":{"$Name":"Screen1","$Type":"Form","$Version":"30","ActionBar":"True","AlignHorizontal":"3","AppName":"ruangong","ShowListsAsJson":"False","Theme":"AppTheme.Light.DarkActionBar","Title":"\u907f\u969c\u76d1\u6d4b","Uuid":"0","$Components":[{"$Name":"\u6c34\u5e73\u5e03\u5c404","$Type":"HorizontalArrangement","$Version":"4","AlignHorizontal":"3","Height":"378","Width":"-2","Uuid":"-1446214067","$Components":[{"$Name":"\u6309\u94ae_\u907f\u969c","$Type":"Button","$Version":"7","Text":"\u907f\u969c","Uuid":"-644814633"},{"$Name":"\u6309\u94ae_\u5b9e\u65f6\u5b9a\u4f4d","$Type":"Button","$Version":"7","Text":"\u5b9e\u65f6\u5b9a\u4f4d","Uuid":"-18939228"},{"$Name":"\u6309\u94ae_\u62e8\u6253\u7535\u8bdd","$Type":"Button","$Version":"7","Text":"\u62e8\u6253\u7535\u8bdd","Uuid":"2062084651"},{"$Name":"\u5217\u8868\u9009\u62e9\u6846_\u84dd\u7259","$Type":"ListPicker","$Version":"9","Text":"\u8fde\u63a5\u8bbe\u5907","Uuid":"-1183153014"}]},{"$Name":"\u6c34\u5e73\u5e03\u5c403","$Type":"HorizontalArrangement","$Version":"4","AlignHorizontal":"3","AlignVertical":"2","Uuid":"-2055779801","$Components":[{"$Name":"\u6807\u7b7e_\u8ddd\u79bb","$Type":"Label","$Version":"5","Text":"\u8ddd\u79bb\uff1a","Uuid":"1009622951"},{"$Name":"\u6587\u672c\u8f93\u5165\u6846_\u8ddd\u79bb","$Type":"TextBox","$Version":"6","ReadOnly":"True","Uuid":"-2128440146"},{"$Name":"\u64ad\u62a5","$Type":"CheckBox","$Version":"2","Text":"\u81ea\u52a8\u64ad\u62a5","Uuid":"405481945"}]},{"$Name":"\u5782\u76f4\u5e03\u5c401","$Type":"VerticalArrangement","$Version":"4","AlignHorizontal":"3","AlignVertical":"3","Height":"-1040","Width":"-2","Uuid":"2081953051","$Components":[{"$Name":"\u6c34\u5e73\u5e03\u5c402","$Type":"HorizontalArrangement","$Version":"4","AlignHorizontal":"3","AlignVertical":"2","Uuid":"177806287","$Components":[{"$Name":"\u6807\u7b7e_\u8ba1\u65f6","$Type":"Label","$Version":"5","Text":"\u8ba1\u65f6\uff1a","Uuid":"-911991431"},{"$Name":"\u6587\u672c\u8f93\u5165\u6846_\u8ba1\u65f6","$Type":"TextBox","$Version":"6","NumbersOnly":"True","Text":"1","Uuid":"-152203493"},{"$Name":"\u6309\u94ae2","$Type":"Button","$Version":"7","Text":"\u786e\u5b9a","Uuid":"-444567807"}]},{"$Name":"\u6c34\u5e73\u5e03\u5c405","$Type":"HorizontalArrangement","$Version":"4","AlignHorizontal":"2","AlignVertical":"3","Width":"-2","Uuid":"-1161251788","$Components":[{"$Name":"\u6309\u94ae_\u5173\u95ed","$Type":"Button","$Version":"7","Text":"\u5173\u95ed","Uuid":"1124974886"}]}]},{"$Name":"\u84dd\u7259\u5ba2\u6237\u7aef1","$Type":"BluetoothClient","$Version":"8","Uuid":"-1413619977"},{"$Name":"\u8ba1\u65f6\u56681","$Type":"Clock","$Version":"4","Uuid":"530919694"},{"$Name":"\u6587\u672c\u8bed\u97f3\u8f6c\u6362\u56681","$Type":"TextToSpeech","$Version":"6","Uuid":"-1761536897"},{"$Name":"\u77ed\u4fe1\u6536\u53d1\u56681","$Type":"Texting","$Version":"5","Uuid":"-1268134884"}]}}
+|#

src/Software/src/appinventor/ai_karlzj/ruangong/Screen1.scm.2023-10-23T14_24_48+0800.backup

@@ -0,0 +1,4 @@
+#|
+$JSON
+{"authURL":["app.gzjkw.net"],"YaVersion":"172","Source":"Form","Properties":{"$Name":"Screen1","$Type":"Form","$Version":"23","AppName":"ruangong","Title":"Screen1","Uuid":"0","$Components":[{"$Name":"\u5217\u8868\u663e\u793a\u68461","$Type":"ListView","$Version":"5","Uuid":"1220671722"},{"$Name":"\u6309\u94ae1","$Type":"Button","$Version":"6","Text":"\u5173\u95ed","Uuid":"-644814633"}]}}
+|#

src/Software/src/appinventor/ai_karlzj/ruangong/Screen1.scm.2023-10-25T15_02_46+0800.backup

@@ -0,0 +1,4 @@
+#|
+$JSON
+{"authURL":["app.gzjkw.net"],"YaVersion":"172","Source":"Form","Properties":{"$Name":"Screen1","$Type":"Form","$Version":"23","AlignHorizontal":"3","AlignVertical":"2","AppName":"ruangong","Title":"Screen1","Uuid":"0","$Components":[{"$Name":"\u6c34\u5e73\u5e03\u5c401","$Type":"HorizontalArrangement","$Version":"3","AlignHorizontal":"3","AlignVertical":"2","Uuid":"177113749","$Components":[{"$Name":"\u6309\u94ae_\u907f\u969c","$Type":"Button","$Version":"6","Text":"\u907f\u969c","Uuid":"-644814633"},{"$Name":"\u6309\u94ae_\u5b9e\u65f6\u5b9a\u4f4d","$Type":"Button","$Version":"6","Text":"\u5b9e\u65f6\u5b9a\u4f4d","Uuid":"-18939228"},{"$Name":"\u6309\u94ae_\u62e8\u6253\u7535\u8bdd","$Type":"Button","$Version":"6","Text":"\u62e8\u6253\u7535\u8bdd","Uuid":"2062084651"}]},{"$Name":"\u5782\u76f4\u5e03\u5c401","$Type":"VerticalArrangement","$Version":"3","AlignHorizontal":"2","AlignVertical":"2","Uuid":"-1007398740","$Components":[{"$Name":"\u6c34\u5e73\u5e03\u5c402","$Type":"HorizontalArrangement","$Version":"3","Uuid":"177806287","$Components":[{"$Name":"\u6807\u7b7e_\u8ba1\u65f6","$Type":"Label","$Version":"4","Text":"\u8ba1\u65f6\uff1a","Uuid":"-911991431"},{"$Name":"\u6587\u672c\u8f93\u5165\u6846_\u8ba1\u65f6","$Type":"TextBox","$Version":"5","Uuid":"-152203493"}]},{"$Name":"\u6c34\u5e73\u5e03\u5c403","$Type":"HorizontalArrangement","$Version":"3","Uuid":"-2055779801","$Components":[{"$Name":"\u6807\u7b7e_\u8ddd\u79bb","$Type":"Label","$Version":"4","Text":"\u8ddd\u79bb\uff1a","Uuid":"1009622951"},{"$Name":"\u6587\u672c\u8f93\u5165\u6846_\u8ddd\u79bb","$Type":"TextBox","$Version":"5","Uuid":"-2128440146"}]},{"$Name":"\u6309\u94ae_\u5173\u95ed","$Type":"Button","$Version":"6","Text":"\u5173\u95ed","Uuid":"1124974886"}]}]}}
+|#

src/Software/src/appinventor/ai_karlzj/ruangong/calling.scm

@@ -0,0 +1,4 @@
+#|
+$JSON
+{"authURL":["app.gzjkw.net","ai2.appinventor.mit.edu"],"YaVersion":"224","Source":"Form","Properties":{"$Name":"calling","$Type":"Form","$Version":"30","ActionBar":"True","AlignHorizontal":"3","AppName":"ruangong","ShowListsAsJson":"False","Theme":"AppTheme.Light.DarkActionBar","Title":"\u62e8\u6253\u7535\u8bdd","Uuid":"0","$Components":[{"$Name":"\u6c34\u5e73\u5e03\u5c401","$Type":"HorizontalArrangement","$Version":"4","AlignHorizontal":"3","Height":"-1040","Width":"-2","Uuid":"497758912","$Components":[{"$Name":"\u6309\u94ae_\u907f\u969c","$Type":"Button","$Version":"7","Text":"\u907f\u969c","Uuid":"-1955423566"},{"$Name":"\u6309\u94ae_\u5b9e\u65f6\u5b9a\u4f4d","$Type":"Button","$Version":"7","Text":"\u5b9e\u65f6\u5b9a\u4f4d","Uuid":"479692292"},{"$Name":"\u6309\u94ae_\u62e8\u6253\u7535\u8bdd","$Type":"Button","$Version":"7","Text":"\u62e8\u6253\u7535\u8bdd","Uuid":"-1181431767"}]},{"$Name":"\u5782\u76f4\u5e03\u5c401","$Type":"VerticalArrangement","$Version":"4","AlignHorizontal":"3","AlignVertical":"2","Uuid":"-1614689866","$Components":[{"$Name":"\u5217\u8868\u9009\u62e9\u6846_\u7535\u8bdd\u5217\u8868","$Type":"ListPicker","$Version":"9","ElementsFromString":"123,19968538899","Text":"\u9009\u62e9\u7d27\u6025\u8054\u7cfb\u4eba","Uuid":"-1795360827"}]},{"$Name":"\u6c34\u5e73\u5e03\u5c402","$Type":"HorizontalArrangement","$Version":"4","AlignHorizontal":"2","AlignVertical":"3","Height":"-1040","Width":"-2","Uuid":"923044023","$Components":[{"$Name":"\u6309\u94ae_\u5173\u95ed","$Type":"Button","$Version":"7","Text":"\u5173\u95ed","Uuid":"2024754233"}]},{"$Name":"\u7535\u8bdd\u62e8\u53f7\u5668_\u62e8\u6253\u7535\u8bdd","$Type":"PhoneCall","$Version":"3","Uuid":"-1369827363"}]}}
+|#

src/Software/src/appinventor/ai_karlzj/ruangong/dingwei.bky.2023-10-26T09_12_23+0800.backup

@@ -0,0 +1,41 @@
+<xml xmlns="http://www.w3.org/1999/xhtml">
+  <block type="component_event" id="l0r/-ENMfb_}qL~ed0!E" x="-472" y="-89">
+    <mutation component_type="Button" instance_name="按钮_避障" event_name="Click"></mutation>
+    <field name="COMPONENT_SELECTOR">按钮_避障</field>
+    <statement name="DO">
+      <block type="controls_openAnotherScreen" id="=fZ9R$eQnx9W=T/0WSns">
+        <value name="SCREEN">
+          <block type="text" id="9b{~^NYOdkLaS]=}B?0n">
+            <field name="TEXT">Screen1</field>
+          </block>
+        </value>
+      </block>
+    </statement>
+  </block>
+  <block type="component_set_get" id="]6?;)6zP7hTG8D.)LDl$" x="-468" y="8">
+    <mutation component_type="Button" set_or_get="get" property_name="Enabled" is_generic="false" instance_name="按钮_实时定位"></mutation>
+    <field name="COMPONENT_SELECTOR">按钮_实时定位</field>
+    <field name="PROP">Enabled</field>
+  </block>
+  <block type="component_event" id="20%u[R^-3+ouiy8=/CZF" x="-475" y="56">
+    <mutation component_type="Button" instance_name="按钮_拨打电话" event_name="Click"></mutation>
+    <field name="COMPONENT_SELECTOR">按钮_拨打电话</field>
+    <statement name="DO">
+      <block type="controls_openAnotherScreen" id="JMzPot8U;!E~]~U4SNd+">
+        <value name="SCREEN">
+          <block type="text" id="rD6.uP~:nv;itN019[.z">
+            <field name="TEXT">calling</field>
+          </block>
+        </value>
+      </block>
+    </statement>
+  </block>
+  <block type="component_event" id="7H89A@N/?oES:zQX.*:v" x="-472" y="152">
+    <mutation component_type="Button" instance_name="按钮_关闭" event_name="Click"></mutation>
+    <field name="COMPONENT_SELECTOR">按钮_关闭</field>
+    <statement name="DO">
+      <block type="controls_closeScreen" id="r1-697xyD#}ga{a..=0l"></block>
+    </statement>
+  </block>
+  <yacodeblocks ya-version="172" language-version="22"></yacodeblocks>
+</xml>

src/Software/src/appinventor/ai_karlzj/ruangong/dingwei.scm

@@ -0,0 +1,4 @@
+#|
+$JSON
+{"authURL":["app.gzjkw.net","ai2.appinventor.mit.edu"],"YaVersion":"224","Source":"Form","Properties":{"$Name":"dingwei","$Type":"Form","$Version":"30","ActionBar":"True","AlignHorizontal":"3","AppName":"ruangong","ShowListsAsJson":"False","Theme":"AppTheme.Light.DarkActionBar","Title":"\u5b9e\u65f6\u5b9a\u4f4d","Uuid":"0","$Components":[{"$Name":"\u6c34\u5e73\u5e03\u5c401","$Type":"HorizontalArrangement","$Version":"4","AlignHorizontal":"3","AlignVertical":"2","Uuid":"-655869917","$Components":[{"$Name":"\u6309\u94ae_\u907f\u969c","$Type":"Button","$Version":"7","Text":"\u907f\u969c","Uuid":"1440681744"},{"$Name":"\u6309\u94ae_\u5b9e\u65f6\u5b9a\u4f4d","$Type":"Button","$Version":"7","Text":"\u5b9e\u65f6\u5b9a\u4f4d","Uuid":"652290387"},{"$Name":"\u6309\u94ae_\u62e8\u6253\u7535\u8bdd","$Type":"Button","$Version":"7","Text":"\u62e8\u6253\u7535\u8bdd","Uuid":"1956743508"},{"$Name":"\u5217\u8868\u9009\u62e9\u6846_\u84dd\u7259","$Type":"ListPicker","$Version":"9","Text":"\u8fde\u63a5\u8bbe\u5907","Uuid":"1464195969"}]},{"$Name":"\u6c34\u5e73\u5e03\u5c403","$Type":"HorizontalArrangement","$Version":"4","AlignHorizontal":"3","AlignVertical":"2","Height":"-1060","Width":"-2","Uuid":"1743176679","$Components":[{"$Name":"Web\u6d4f\u89c8\u68461","$Type":"WebViewer","$Version":"10","Uuid":"177751501"}]},{"$Name":"\u6c34\u5e73\u5e03\u5c402","$Type":"HorizontalArrangement","$Version":"4","AlignHorizontal":"3","AlignVertical":"2","Uuid":"785425026","$Components":[{"$Name":"\u5237\u65b0","$Type":"Button","$Version":"7","Text":"\u5237\u65b0","Uuid":"-990679099"}]},{"$Name":"\u6c34\u5e73\u5e03\u5c404","$Type":"HorizontalArrangement","$Version":"4","AlignHorizontal":"2","AlignVertical":"3","Height":"-1020","Width":"-2","Uuid":"1670022820","$Components":[{"$Name":"\u6309\u94ae_\u5173\u95ed","$Type":"Button","$Version":"7","Text":"\u5173\u95ed","Uuid":"-1949803666"}]},{"$Name":"\u84dd\u7259\u5ba2\u6237\u7aef1","$Type":"BluetoothClient","$Version":"8","Uuid":"985772490"},{"$Name":"\u8ba1\u65f6\u56681","$Type":"Clock","$Version":"4","TimerInterval":"40000","Uuid":"-415083639"},{"$Name":"\u4f4d\u7f6e\u4f20\u611f\u56681","$Type":"LocationSensor","$Version":"3","Uuid":"-939539378"},{"$Name":"Web\u5ba2\u6237\u7aef1","$Type":"Web","$Version":"8","Uuid":"-1721494346"},{"$Name":"\u77ed\u4fe1\u6536\u53d1\u56681","$Type":"Texting","$Version":"5","Uuid":"-459111995"}]}}
+|#

src/Software/src/appinventor/ai_karlzj/ruangong/dingwei.scm.2023-10-26T09_12_57+0800.backup

@@ -0,0 +1,4 @@
+#|
+$JSON
+{"authURL":["app.gzjkw.net"],"YaVersion":"172","Source":"Form","Properties":{"$Name":"dingwei","$Type":"Form","$Version":"23","AlignHorizontal":"3","AlignVertical":"2","AppName":"ruangong","Title":"dingwei","Uuid":"0","$Components":[{"$Name":"\u6c34\u5e73\u5e03\u5c401","$Type":"HorizontalArrangement","$Version":"3","AlignHorizontal":"3","Uuid":"-655869917","$Components":[{"$Name":"\u6309\u94ae_\u907f\u969c","$Type":"Button","$Version":"6","Text":"\u907f\u969c","Uuid":"1440681744"},{"$Name":"\u6309\u94ae_\u5b9e\u65f6\u5b9a\u4f4d","$Type":"Button","$Version":"6","Text":"\u5b9e\u65f6\u5b9a\u4f4d","Uuid":"652290387"},{"$Name":"\u6309\u94ae_\u62e8\u6253\u7535\u8bdd","$Type":"Button","$Version":"6","Text":"\u62e8\u6253\u7535\u8bdd","Uuid":"1956743508"}]},{"$Name":"\u5782\u76f4\u5e03\u5c401","$Type":"VerticalArrangement","$Version":"3","AlignHorizontal":"2","Uuid":"525050555","$Components":[{"$Name":"\u6c34\u5e73\u5e03\u5c402","$Type":"HorizontalArrangement","$Version":"3","Uuid":"785425026","$Components":[{"$Name":"\u6807\u7b7e_\u8ba1\u65f6\u63d0\u793a","$Type":"Label","$Version":"4","Text":"\u8ba1\u65f6\uff1a","Uuid":"-1133475828"},{"$Name":"\u6587\u672c\u8f93\u5165\u6846_\u8ba1\u65f6","$Type":"TextBox","$Version":"5","Uuid":"2119337786"}]},{"$Name":"\u6309\u94ae_\u5173\u95ed","$Type":"Button","$Version":"6","Text":"\u5173\u95ed","Uuid":"139342436"}]}]}}
+|#

src/Software/youngandroidproject/project.properties

@@ -0,0 +1,19 @@
+#
+#Tue Nov 14 13:34:00 UTC 2023
+source=../src
+name=ruangong
+defaultfilescope=App
+main=appinventor.ai_dustinzrm.ruangong.Screen1
+color.accent=&HFFFF4081
+sizing=Responsive
+assets=../assets
+theme=AppTheme.Light.DarkActionBar
+showlistsasjson=False
+useslocation=False
+aname=ruangong
+actionbar=True
+color.primary=&HFF3F51B5
+build=../build
+versionname=1.0
+versioncode=1
+color.primary.dark=&HFF303F9F

src/esp32/hardware/cores/esp32/Arduino.h

@@ -0,0 +1,225 @@
+/*
+ Arduino.h - Main include file for the Arduino SDK
+ Copyright (c) 2005-2013 Arduino Team.  All right reserved.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#ifndef Arduino_h
+#define Arduino_h
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdarg.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <inttypes.h>
+
+#include "esp_arduino_version.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "freertos/semphr.h"
+#include "esp32-hal.h"
+#include "esp8266-compat.h"
+#include "soc/gpio_reg.h"
+
+#include "stdlib_noniso.h"
+#include "binary.h"
+
+#define PI 3.1415926535897932384626433832795
+#define HALF_PI 1.5707963267948966192313216916398
+#define TWO_PI 6.283185307179586476925286766559
+#define DEG_TO_RAD 0.017453292519943295769236907684886
+#define RAD_TO_DEG 57.295779513082320876798154814105
+#define EULER 2.718281828459045235360287471352
+
+#define SERIAL  0x0
+#define DISPLAY 0x1
+
+#define LSBFIRST 0
+#define MSBFIRST 1
+
+//Interrupt Modes
+#define RISING    0x01
+#define FALLING   0x02
+#define CHANGE    0x03
+#define ONLOW     0x04
+#define ONHIGH    0x05
+#define ONLOW_WE  0x0C
+#define ONHIGH_WE 0x0D
+
+#define DEFAULT 1
+#define EXTERNAL 0
+
+#ifndef __STRINGIFY
+#define __STRINGIFY(a) #a
+#endif
+
+// can't define max() / min() because of conflicts with C++
+#define _min(a,b) ((a)<(b)?(a):(b))  
+#define _max(a,b) ((a)>(b)?(a):(b))
+#define _abs(x) ((x)>0?(x):-(x))  // abs() comes from STL
+#define constrain(amt,low,high) ((amt)<(low)?(low):((amt)>(high)?(high):(amt)))
+#define _round(x)     ((x)>=0?(long)((x)+0.5):(long)((x)-0.5))  // round() comes from STL
+#define radians(deg) ((deg)*DEG_TO_RAD)
+#define degrees(rad) ((rad)*RAD_TO_DEG)
+#define sq(x) ((x)*(x))
+
+// ESP32xx runs FreeRTOS... disabling interrupts can lead to issues, such as Watchdog Timeout
+#define sei() portENABLE_INTERRUPTS()
+#define cli() portDISABLE_INTERRUPTS()
+#define interrupts() sei()
+#define noInterrupts() cli()
+
+#define clockCyclesPerMicrosecond() ( (long int)getCpuFrequencyMhz() )
+#define clockCyclesToMicroseconds(a) ( (a) / clockCyclesPerMicrosecond() )
+#define microsecondsToClockCycles(a) ( (a) * clockCyclesPerMicrosecond() )
+
+#define lowByte(w) ((uint8_t) ((w) & 0xff))
+#define highByte(w) ((uint8_t) ((w) >> 8))
+
+#define bitRead(value, bit) (((value) >> (bit)) & 0x01)
+#define bitSet(value, bit) ((value) |= (1UL << (bit)))
+#define bitClear(value, bit) ((value) &= ~(1UL << (bit)))
+#define bitToggle(value, bit) ((value) ^= (1UL << (bit)))
+#define bitWrite(value, bit, bitvalue) ((bitvalue) ? bitSet(value, bit) : bitClear(value, bit))
+
+// avr-libc defines _NOP() since 1.6.2
+#ifndef _NOP
+#define _NOP() do { __asm__ volatile ("nop"); } while (0)
+#endif
+
+#define bit(b) (1UL << (b))
+#define _BV(b) (1UL << (b))
+
+#define digitalPinToTimer(pin)      (0)
+#define analogInPinToBit(P)         (P)
+#if SOC_GPIO_PIN_COUNT <= 32
+#define digitalPinToPort(pin)       (0)
+#define digitalPinToBitMask(pin)    (1UL << digitalPinToGPIONumber(pin))
+#define portOutputRegister(port)    ((volatile uint32_t*)GPIO_OUT_REG)
+#define portInputRegister(port)     ((volatile uint32_t*)GPIO_IN_REG)
+#define portModeRegister(port)      ((volatile uint32_t*)GPIO_ENABLE_REG)
+#elif SOC_GPIO_PIN_COUNT <= 64
+#define digitalPinToPort(pin)       ((digitalPinToGPIONumber(pin)>31)?1:0)
+#define digitalPinToBitMask(pin)    (1UL << (digitalPinToGPIONumber(pin)&31))
+#define portOutputRegister(port)    ((volatile uint32_t*)((port)?GPIO_OUT1_REG:GPIO_OUT_REG))
+#define portInputRegister(port)     ((volatile uint32_t*)((port)?GPIO_IN1_REG:GPIO_IN_REG))
+#define portModeRegister(port)      ((volatile uint32_t*)((port)?GPIO_ENABLE1_REG:GPIO_ENABLE_REG))
+#else
+#error SOC_GPIO_PIN_COUNT > 64 not implemented
+#endif
+
+#define NOT_A_PIN -1
+#define NOT_A_PORT -1
+#define NOT_AN_INTERRUPT -1
+#define NOT_ON_TIMER 0
+
+typedef bool boolean;
+typedef uint8_t byte;
+typedef unsigned int word;
+
+#ifdef __cplusplus
+void setup(void);
+void loop(void);
+
+// The default is using Real Hardware random number generator  
+// But when randomSeed() is called, it turns to Psedo random
+// generator, exactly as done in Arduino mainstream
+long random(long);
+long random(long, long);
+// Calling randomSeed() will make random()
+// using pseudo random like in Arduino
+void randomSeed(unsigned long);
+// Allow the Application to decide if the random generator
+// will use Real Hardware random generation (true - default)
+// or Pseudo random generation (false) as in Arduino MainStream
+void useRealRandomGenerator(bool useRandomHW);
+#endif
+long map(long, long, long, long, long);
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+void init(void);
+void initVariant(void);
+void initArduino(void);
+
+unsigned long pulseIn(uint8_t pin, uint8_t state, unsigned long timeout);
+unsigned long pulseInLong(uint8_t pin, uint8_t state, unsigned long timeout);
+
+uint8_t shiftIn(uint8_t dataPin, uint8_t clockPin, uint8_t bitOrder);
+void shiftOut(uint8_t dataPin, uint8_t clockPin, uint8_t bitOrder, uint8_t val);
+
+#ifdef __cplusplus
+}
+
+#include <algorithm>
+#include <cmath>
+
+#include "WCharacter.h"
+#include "WString.h"
+#include "Stream.h"
+#include "Printable.h"
+#include "Print.h"
+#include "IPAddress.h"
+#include "Client.h"
+#include "Server.h"
+#include "Udp.h"
+#include "HardwareSerial.h"
+#include "Esp.h"
+#include "esp32/spiram.h"
+
+// Use float-compatible stl abs() and round(), we don't use Arduino macros to avoid issues with the C++ libraries
+using std::abs;
+using std::isinf;
+using std::isnan;
+using std::max;
+using std::min;
+using std::round;
+
+uint16_t makeWord(uint16_t w);
+uint16_t makeWord(uint8_t h, uint8_t l);
+
+#define word(...) makeWord(__VA_ARGS__)
+
+size_t getArduinoLoopTaskStackSize(void);
+#define SET_LOOP_TASK_STACK_SIZE(sz) size_t getArduinoLoopTaskStackSize() { return sz;}
+
+// allows user to bypass esp_spiram_test()
+#define BYPASS_SPIRAM_TEST(bypass) bool testSPIRAM(void) { if (bypass) return true; else return esp_spiram_test(); }
+
+unsigned long pulseIn(uint8_t pin, uint8_t state, unsigned long timeout = 1000000L);
+unsigned long pulseInLong(uint8_t pin, uint8_t state, unsigned long timeout = 1000000L);
+
+extern "C" bool getLocalTime(struct tm * info, uint32_t ms = 5000);
+extern "C" void configTime(long gmtOffset_sec, int daylightOffset_sec,
+        const char* server1, const char* server2 = nullptr, const char* server3 = nullptr);
+extern "C" void configTzTime(const char* tz,
+        const char* server1, const char* server2 = nullptr, const char* server3 = nullptr);
+
+void setToneChannel(uint8_t channel = 0);
+void tone(uint8_t _pin, unsigned int frequency, unsigned long duration = 0);
+void noTone(uint8_t _pin);
+
+#endif /* __cplusplus */
+
+#include "pins_arduino.h"
+#include "io_pin_remap.h"
+
+#endif /* _ESP32_CORE_ARDUINO_H_ */

src/esp32/hardware/cores/esp32/Client.h

@@ -0,0 +1,48 @@
+/*
+ Client.h - Base class that provides Client
+ Copyright (c) 2011 Adrian McEwen.  All right reserved.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#ifndef client_h
+#define client_h
+#include "Print.h"
+#include "Stream.h"
+#include "IPAddress.h"
+
+class Client: public Stream
+{
+public:
+    virtual int connect(IPAddress ip, uint16_t port) =0;
+    virtual int connect(const char *host, uint16_t port) =0;
+    virtual size_t write(uint8_t) =0;
+    virtual size_t write(const uint8_t *buf, size_t size) =0;
+    virtual int available() = 0;
+    virtual int read() = 0;
+    virtual int read(uint8_t *buf, size_t size) = 0;
+    virtual int peek() = 0;
+    virtual void flush() = 0;
+    virtual void stop() = 0;
+    virtual uint8_t connected() = 0;
+    virtual operator bool() = 0;
+protected:
+    uint8_t* rawIPAddress(IPAddress& addr)
+    {
+        return addr.raw_address();
+    }
+};
+
+#endif

src/esp32/hardware/cores/esp32/Esp.cpp

@@ -0,0 +1,450 @@
+/*
+ Esp.cpp - ESP31B-specific APIs
+ Copyright (c) 2015 Ivan Grokhotkov. All rights reserved.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include "Arduino.h"
+#include "Esp.h"
+#include "esp_sleep.h"
+#include "esp_spi_flash.h"
+#include <memory>
+#include <soc/soc.h>
+#include <esp_partition.h>
+extern "C" {
+#include "esp_ota_ops.h"
+#include "esp_image_format.h"
+}
+#include <MD5Builder.h>
+
+#include "soc/spi_reg.h"
+#include "esp_system.h"
+#ifdef ESP_IDF_VERSION_MAJOR // IDF 4+
+#if CONFIG_IDF_TARGET_ESP32 // ESP32/PICO-D4
+#include "esp32/rom/spi_flash.h"
+#include "soc/efuse_reg.h"
+#define ESP_FLASH_IMAGE_BASE 0x1000     // Flash offset containing flash size and spi mode
+#elif CONFIG_IDF_TARGET_ESP32S2
+#include "esp32s2/rom/spi_flash.h"
+#include "soc/efuse_reg.h"
+#define ESP_FLASH_IMAGE_BASE 0x1000
+#elif CONFIG_IDF_TARGET_ESP32S3
+#include "esp32s3/rom/spi_flash.h"
+#include "soc/efuse_reg.h"
+#define ESP_FLASH_IMAGE_BASE 0x0000     // Esp32s3 is located at 0x0000
+#elif CONFIG_IDF_TARGET_ESP32C3
+#include "esp32c3/rom/spi_flash.h"
+#define ESP_FLASH_IMAGE_BASE 0x0000     // Esp32c3 is located at 0x0000
+#else 
+#error Target CONFIG_IDF_TARGET is not supported
+#endif
+#else // ESP32 Before IDF 4.0
+#include "rom/spi_flash.h"
+#define ESP_FLASH_IMAGE_BASE 0x1000
+#endif
+
+// REG_SPI_BASE is not defined for S3/C3 ??
+
+#if CONFIG_IDF_TARGET_ESP32S3 || CONFIG_IDF_TARGET_ESP32C3
+  #ifndef REG_SPI_BASE
+  #define REG_SPI_BASE(i)     (DR_REG_SPI1_BASE + (((i)>1) ? (((i)* 0x1000) + 0x20000) : (((~(i)) & 1)* 0x1000 )))
+  #endif // REG_SPI_BASE
+#endif // TARGET
+
+/**
+ * User-defined Literals
+ *  usage:
+ *
+ *   uint32_t = test = 10_MHz; // --> 10000000
+ */
+
+unsigned long long operator"" _kHz(unsigned long long x)
+{
+    return x * 1000;
+}
+
+unsigned long long operator"" _MHz(unsigned long long x)
+{
+    return x * 1000 * 1000;
+}
+
+unsigned long long operator"" _GHz(unsigned long long x)
+{
+    return x * 1000 * 1000 * 1000;
+}
+
+unsigned long long operator"" _kBit(unsigned long long x)
+{
+    return x * 1024;
+}
+
+unsigned long long operator"" _MBit(unsigned long long x)
+{
+    return x * 1024 * 1024;
+}
+
+unsigned long long operator"" _GBit(unsigned long long x)
+{
+    return x * 1024 * 1024 * 1024;
+}
+
+unsigned long long operator"" _kB(unsigned long long x)
+{
+    return x * 1024;
+}
+
+unsigned long long operator"" _MB(unsigned long long x)
+{
+    return x * 1024 * 1024;
+}
+
+unsigned long long operator"" _GB(unsigned long long x)
+{
+    return x * 1024 * 1024 * 1024;
+}
+
+
+EspClass ESP;
+
+void EspClass::deepSleep(uint32_t time_us)
+{
+    esp_deep_sleep(time_us);
+}
+
+void EspClass::restart(void)
+{
+    esp_restart();
+}
+
+uint32_t EspClass::getHeapSize(void)
+{
+    multi_heap_info_t info;
+    heap_caps_get_info(&info, MALLOC_CAP_INTERNAL);
+    return info.total_free_bytes + info.total_allocated_bytes;
+}
+
+uint32_t EspClass::getFreeHeap(void)
+{
+    return heap_caps_get_free_size(MALLOC_CAP_INTERNAL);
+}
+
+uint32_t EspClass::getMinFreeHeap(void)
+{
+    return heap_caps_get_minimum_free_size(MALLOC_CAP_INTERNAL);
+}
+
+uint32_t EspClass::getMaxAllocHeap(void)
+{
+    return heap_caps_get_largest_free_block(MALLOC_CAP_INTERNAL);
+}
+
+uint32_t EspClass::getPsramSize(void)
+{
+	if(psramFound()){
+	    multi_heap_info_t info;
+	    heap_caps_get_info(&info, MALLOC_CAP_SPIRAM);
+	    return info.total_free_bytes + info.total_allocated_bytes;
+	}
+	return 0;
+}
+
+uint32_t EspClass::getFreePsram(void)
+{
+	if(psramFound()){
+	    return heap_caps_get_free_size(MALLOC_CAP_SPIRAM);
+	}
+	return 0;
+}
+
+uint32_t EspClass::getMinFreePsram(void)
+{
+	if(psramFound()){
+	    return heap_caps_get_minimum_free_size(MALLOC_CAP_SPIRAM);
+	}
+	return 0;
+}
+
+uint32_t EspClass::getMaxAllocPsram(void)
+{
+	if(psramFound()){
+	    return heap_caps_get_largest_free_block(MALLOC_CAP_SPIRAM);
+	}
+	return 0;
+}
+
+static uint32_t sketchSize(sketchSize_t response) {
+    esp_image_metadata_t data;
+    const esp_partition_t *running = esp_ota_get_running_partition();
+    if (!running) return 0;
+    const esp_partition_pos_t running_pos  = {
+        .offset = running->address,
+        .size = running->size,
+    };
+    data.start_addr = running_pos.offset;
+    esp_image_verify(ESP_IMAGE_VERIFY, &running_pos, &data);
+    if (response) {
+        return running_pos.size - data.image_len;
+    } else {
+        return data.image_len;
+    }
+}
+
+uint32_t EspClass::getSketchSize () {
+    return sketchSize(SKETCH_SIZE_TOTAL);
+}
+
+String EspClass::getSketchMD5()
+{
+    static String result;
+    if (result.length()) {
+        return result;
+    }
+    uint32_t lengthLeft = getSketchSize();
+
+    const esp_partition_t *running = esp_ota_get_running_partition();
+    if (!running) {
+        log_e("Partition could not be found");
+
+        return String();
+    }
+    const size_t bufSize = SPI_FLASH_SEC_SIZE;
+    std::unique_ptr<uint8_t[]> buf(new uint8_t[bufSize]);
+    uint32_t offset = 0;
+    if(!buf.get()) {
+        log_e("Not enough memory to allocate buffer");
+
+        return String();
+    }
+    MD5Builder md5;
+    md5.begin();
+    while( lengthLeft > 0) {
+        size_t readBytes = (lengthLeft < bufSize) ? lengthLeft : bufSize;
+        if (!ESP.flashRead(running->address + offset, reinterpret_cast<uint32_t*>(buf.get()), (readBytes + 3) & ~3)) {
+            log_e("Could not read buffer from flash");
+
+            return String();
+        }
+        md5.add(buf.get(), readBytes);
+        lengthLeft -= readBytes;
+        offset += readBytes;
+    }
+    md5.calculate();
+    result = md5.toString();
+    return result;
+}
+
+uint32_t EspClass::getFreeSketchSpace () {
+    const esp_partition_t* _partition = esp_ota_get_next_update_partition(NULL);
+    if(!_partition){
+        return 0;
+    }
+
+    return _partition->size;
+}
+
+uint8_t EspClass::getChipRevision(void)
+{
+    esp_chip_info_t chip_info;
+    esp_chip_info(&chip_info);
+    return chip_info.revision;
+}
+
+const char * EspClass::getChipModel(void)
+{
+#if CONFIG_IDF_TARGET_ESP32
+    uint32_t chip_ver = REG_GET_FIELD(EFUSE_BLK0_RDATA3_REG, EFUSE_RD_CHIP_VER_PKG);
+    uint32_t pkg_ver = chip_ver & 0x7;
+    switch (pkg_ver) {
+        case EFUSE_RD_CHIP_VER_PKG_ESP32D0WDQ6 :
+            if (getChipRevision() == 3)
+                return "ESP32-D0WDQ6-V3";  
+            else
+                return "ESP32-D0WDQ6";
+        case EFUSE_RD_CHIP_VER_PKG_ESP32D0WDQ5 :
+            if (getChipRevision() == 3)
+                return "ESP32-D0WD-V3";  
+            else
+                return "ESP32-D0WD";
+        case EFUSE_RD_CHIP_VER_PKG_ESP32D2WDQ5 :
+            return "ESP32-D2WD";
+        case EFUSE_RD_CHIP_VER_PKG_ESP32PICOD2 :
+            return "ESP32-PICO-D2";
+        case EFUSE_RD_CHIP_VER_PKG_ESP32PICOD4 :
+            return "ESP32-PICO-D4";
+        case EFUSE_RD_CHIP_VER_PKG_ESP32PICOV302 :
+            return "ESP32-PICO-V3-02";
+        case EFUSE_RD_CHIP_VER_PKG_ESP32D0WDR2V3 :
+            return "ESP32-D0WDR2-V3";
+        default:
+            return "Unknown";
+    }
+#elif CONFIG_IDF_TARGET_ESP32S2
+    uint32_t pkg_ver = REG_GET_FIELD(EFUSE_RD_MAC_SPI_SYS_3_REG, EFUSE_PKG_VERSION);
+    switch (pkg_ver) {
+    case 0:
+      return "ESP32-S2";
+    case 1:
+      return "ESP32-S2FH16";
+    case 2:
+      return "ESP32-S2FH32";
+    default:
+      return "ESP32-S2 (Unknown)";
+    }
+#elif CONFIG_IDF_TARGET_ESP32S3
+    return "ESP32-S3";
+#elif CONFIG_IDF_TARGET_ESP32C3
+    return "ESP32-C3";
+#endif
+}
+
+uint8_t EspClass::getChipCores(void)
+{
+    esp_chip_info_t chip_info;
+    esp_chip_info(&chip_info);
+    return chip_info.cores;
+}
+
+const char * EspClass::getSdkVersion(void)
+{
+    return esp_get_idf_version();
+}
+
+uint32_t ESP_getFlashChipId(void)
+{
+  uint32_t id = g_rom_flashchip.device_id;
+  id = ((id & 0xff) << 16) | ((id >> 16) & 0xff) | (id & 0xff00);
+  return id;
+}
+
+uint32_t EspClass::getFlashChipSize(void)
+{
+  uint32_t id = (ESP_getFlashChipId() >> 16) & 0xFF;
+  return 2 << (id - 1);
+}
+
+uint32_t EspClass::getFlashChipSpeed(void)
+{
+    esp_image_header_t fhdr;
+    if(flashRead(ESP_FLASH_IMAGE_BASE, (uint32_t*)&fhdr, sizeof(esp_image_header_t)) && fhdr.magic != ESP_IMAGE_HEADER_MAGIC) {
+        return 0;
+    }
+    return magicFlashChipSpeed(fhdr.spi_speed);
+}
+
+FlashMode_t EspClass::getFlashChipMode(void)
+{
+   #if CONFIG_IDF_TARGET_ESP32S2
+   uint32_t spi_ctrl = REG_READ(PERIPHS_SPI_FLASH_CTRL);
+   #else
+   uint32_t spi_ctrl = REG_READ(SPI_CTRL_REG(0));
+   #endif
+   /* Not all of the following constants are already defined in older versions of spi_reg.h, so do it manually for now*/
+   if (spi_ctrl & BIT(24)) { //SPI_FREAD_QIO
+       return (FM_QIO);
+   } else if (spi_ctrl & BIT(20)) { //SPI_FREAD_QUAD
+       return (FM_QOUT);
+   } else if (spi_ctrl &  BIT(23)) { //SPI_FREAD_DIO
+       return (FM_DIO);
+   } else if (spi_ctrl & BIT(14)) { // SPI_FREAD_DUAL
+       return (FM_DOUT);
+   } else if (spi_ctrl & BIT(13)) { //SPI_FASTRD_MODE
+       return (FM_FAST_READ);
+   } else {
+       return (FM_SLOW_READ);
+   }
+   return (FM_DOUT);
+}
+
+uint32_t EspClass::magicFlashChipSize(uint8_t byte)
+{
+    switch(byte & 0x0F) {
+    case 0x0: // 8 MBit (1MB)
+        return (1_MB);
+    case 0x1: // 16 MBit (2MB)
+        return (2_MB);
+    case 0x2: // 32 MBit (4MB)
+        return (4_MB);
+    case 0x3: // 64 MBit (8MB)
+        return (8_MB);
+    case 0x4: // 128 MBit (16MB)
+        return (16_MB);
+    default: // fail?
+        return 0;
+    }
+}
+
+uint32_t EspClass::magicFlashChipSpeed(uint8_t byte)
+{
+    switch(byte & 0x0F) {
+    case 0x0: // 40 MHz
+        return (40_MHz);
+    case 0x1: // 26 MHz
+        return (26_MHz);
+    case 0x2: // 20 MHz
+        return (20_MHz);
+    case 0xf: // 80 MHz
+        return (80_MHz);
+    default: // fail?
+        return 0;
+    }
+}
+
+FlashMode_t EspClass::magicFlashChipMode(uint8_t byte)
+{
+    FlashMode_t mode = (FlashMode_t) byte;
+    if(mode > FM_SLOW_READ) {
+        mode = FM_UNKNOWN;
+    }
+    return mode;
+}
+
+bool EspClass::flashEraseSector(uint32_t sector)
+{
+    return spi_flash_erase_sector(sector) == ESP_OK;
+}
+
+// Warning: These functions do not work with encrypted flash
+bool EspClass::flashWrite(uint32_t offset, uint32_t *data, size_t size)
+{
+    return spi_flash_write(offset, (uint32_t*) data, size) == ESP_OK;
+}
+
+bool EspClass::flashRead(uint32_t offset, uint32_t *data, size_t size)
+{
+    return spi_flash_read(offset, (uint32_t*) data, size) == ESP_OK;
+}
+
+bool EspClass::partitionEraseRange(const esp_partition_t *partition, uint32_t offset, size_t size) 
+{
+    return esp_partition_erase_range(partition, offset, size) == ESP_OK;
+}
+
+bool EspClass::partitionWrite(const esp_partition_t *partition, uint32_t offset, uint32_t *data, size_t size) 
+{
+    return esp_partition_write(partition, offset, data, size) == ESP_OK;
+}
+
+bool EspClass::partitionRead(const esp_partition_t *partition, uint32_t offset, uint32_t *data, size_t size) 
+{
+    return esp_partition_read(partition, offset, data, size) == ESP_OK;
+}
+
+uint64_t EspClass::getEfuseMac(void)
+{
+    uint64_t _chipmacid = 0LL;
+    esp_efuse_mac_get_default((uint8_t*) (&_chipmacid));
+    return _chipmacid;
+}

src/esp32/hardware/cores/esp32/Esp.h

@@ -0,0 +1,119 @@
+/*
+ Esp.h - ESP31B-specific APIs
+ Copyright (c) 2015 Ivan Grokhotkov. All rights reserved.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#ifndef ESP_H
+#define ESP_H
+
+#include <Arduino.h>
+#include <esp_partition.h>
+#include <hal/cpu_hal.h>
+
+/**
+ * AVR macros for WDT managment
+ */
+typedef enum {
+    WDTO_0MS    = 0,   //!< WDTO_0MS
+    WDTO_15MS   = 15,  //!< WDTO_15MS
+    WDTO_30MS   = 30,  //!< WDTO_30MS
+    WDTO_60MS   = 60,  //!< WDTO_60MS
+    WDTO_120MS  = 120, //!< WDTO_120MS
+    WDTO_250MS  = 250, //!< WDTO_250MS
+    WDTO_500MS  = 500, //!< WDTO_500MS
+    WDTO_1S     = 1000,//!< WDTO_1S
+    WDTO_2S     = 2000,//!< WDTO_2S
+    WDTO_4S     = 4000,//!< WDTO_4S
+    WDTO_8S     = 8000 //!< WDTO_8S
+} WDTO_t;
+
+
+typedef enum {
+    FM_QIO = 0x00,
+    FM_QOUT = 0x01,
+    FM_DIO = 0x02,
+    FM_DOUT = 0x03,
+    FM_FAST_READ = 0x04,
+    FM_SLOW_READ = 0x05,
+    FM_UNKNOWN = 0xff
+} FlashMode_t;
+
+typedef enum {
+    SKETCH_SIZE_TOTAL = 0,
+    SKETCH_SIZE_FREE = 1
+} sketchSize_t;
+
+class EspClass
+{
+public:
+    EspClass() {}
+    ~EspClass() {}
+    void restart();
+
+    //Internal RAM
+    uint32_t getHeapSize(); //total heap size
+    uint32_t getFreeHeap(); //available heap
+    uint32_t getMinFreeHeap(); //lowest level of free heap since boot
+    uint32_t getMaxAllocHeap(); //largest block of heap that can be allocated at once
+
+    //SPI RAM
+    uint32_t getPsramSize();
+    uint32_t getFreePsram();
+    uint32_t getMinFreePsram();
+    uint32_t getMaxAllocPsram();
+
+    uint8_t getChipRevision();
+    const char * getChipModel();
+    uint8_t getChipCores();
+    uint32_t getCpuFreqMHz(){ return getCpuFrequencyMhz(); }
+    inline uint32_t getCycleCount() __attribute__((always_inline));
+    const char * getSdkVersion();
+
+    void deepSleep(uint32_t time_us);
+
+    uint32_t getFlashChipSize();
+    uint32_t getFlashChipSpeed();
+    FlashMode_t getFlashChipMode();
+
+    uint32_t magicFlashChipSize(uint8_t byte);
+    uint32_t magicFlashChipSpeed(uint8_t byte);
+    FlashMode_t magicFlashChipMode(uint8_t byte);
+
+    uint32_t getSketchSize();
+    String getSketchMD5();
+    uint32_t getFreeSketchSpace();
+
+    bool flashEraseSector(uint32_t sector);
+    bool flashWrite(uint32_t offset, uint32_t *data, size_t size);
+    bool flashRead(uint32_t offset, uint32_t *data, size_t size);
+
+    bool partitionEraseRange(const esp_partition_t *partition, uint32_t offset, size_t size);
+    bool partitionWrite(const esp_partition_t *partition, uint32_t offset, uint32_t *data, size_t size);
+    bool partitionRead(const esp_partition_t *partition, uint32_t offset, uint32_t *data, size_t size);
+
+    uint64_t getEfuseMac();
+
+};
+
+uint32_t ARDUINO_ISR_ATTR EspClass::getCycleCount()
+{
+    return cpu_hal_get_cycle_count();
+}
+
+extern EspClass ESP;
+
+#endif //ESP_H

src/esp32/hardware/cores/esp32/FirmwareMSC.cpp

@@ -0,0 +1,424 @@
+// Copyright 2015-2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+#include "FirmwareMSC.h"
+
+#if CONFIG_TINYUSB_MSC_ENABLED
+
+#include <cstring>
+#include "esp_partition.h"
+#include "esp_ota_ops.h"
+#include "esp32-hal.h"
+#include "pins_arduino.h"
+#include "firmware_msc_fat.h"
+
+#ifndef USB_FW_MSC_VENDOR_ID
+#define USB_FW_MSC_VENDOR_ID "ESP32" //max 8 chars
+#endif
+#ifndef USB_FW_MSC_PRODUCT_ID
+#define USB_FW_MSC_PRODUCT_ID "Firmware MSC"//max 16 chars
+#endif
+#ifndef USB_FW_MSC_PRODUCT_REVISION
+#define USB_FW_MSC_PRODUCT_REVISION "1.0" //max 4 chars
+#endif
+#ifndef USB_FW_MSC_VOLUME_NAME
+#define USB_FW_MSC_VOLUME_NAME "ESP32-FWMSC" //max 11 chars
+#endif
+#ifndef USB_FW_MSC_SERIAL_NUMBER
+#define USB_FW_MSC_SERIAL_NUMBER 0x00000000
+#endif
+
+ESP_EVENT_DEFINE_BASE(ARDUINO_FIRMWARE_MSC_EVENTS);
+esp_err_t arduino_usb_event_post(esp_event_base_t event_base, int32_t event_id, void *event_data, size_t event_data_size, TickType_t ticks_to_wait);
+esp_err_t arduino_usb_event_handler_register_with(esp_event_base_t event_base, int32_t event_id, esp_event_handler_t event_handler, void *event_handler_arg);
+
+//General Variables
+static uint8_t * msc_ram_disk = NULL;
+static fat_boot_sector_t * msc_boot = NULL;
+static uint8_t * msc_table = NULL;
+static uint16_t msc_table_sectors = 0;
+static uint16_t msc_total_sectors = 0;
+static bool mcs_is_fat16 = false;
+
+//Firmware Read
+static const esp_partition_t* msc_run_partition = NULL;
+static uint16_t fw_start_sector = 0;
+static uint16_t fw_end_sector = 0;
+static size_t fw_size = 0;
+static fat_dir_entry_t * fw_entry = NULL;
+
+//Firmware Write
+typedef enum {
+  MSC_UPDATE_IDLE,
+  MSC_UPDATE_STARTING,
+  MSC_UPDATE_RUNNING,
+  MSC_UPDATE_END
+} msc_update_state_t;
+
+static const esp_partition_t* msc_ota_partition = NULL;
+static msc_update_state_t msc_update_state = MSC_UPDATE_IDLE;
+static uint16_t msc_update_start_sector = 0;
+static uint32_t msc_update_bytes_written = 0;
+static fat_dir_entry_t * msc_update_entry = NULL;
+
+static uint32_t get_firmware_size(const esp_partition_t* partition){
+  esp_image_metadata_t data;
+  const esp_partition_pos_t running_pos  = {
+      .offset = partition->address,
+      .size = partition->size,
+  };
+  data.start_addr = running_pos.offset;
+  esp_image_verify(ESP_IMAGE_VERIFY, &running_pos, &data);
+  return data.image_len;
+}
+
+//Get number of sectors required based on the size of the firmware and OTA partition
+static size_t msc_update_get_required_disk_sectors(){
+  size_t data_sectors = 16;
+  size_t total_sectors = 0;
+  msc_run_partition = esp_ota_get_running_partition();
+  msc_ota_partition = esp_ota_get_next_update_partition(NULL);
+  if(msc_run_partition){
+    fw_size = get_firmware_size(msc_run_partition);
+    data_sectors += FAT_SIZE_TO_SECTORS(fw_size);
+    log_d("APP size: %u (%u sectors)", fw_size, FAT_SIZE_TO_SECTORS(fw_size));
+  } else {
+    log_w("APP partition not found. Reading disabled");
+  }
+  if(msc_ota_partition){
+    data_sectors += FAT_SIZE_TO_SECTORS(msc_ota_partition->size);
+    log_d("OTA size: %u (%u sectors)", msc_ota_partition->size, FAT_SIZE_TO_SECTORS(msc_ota_partition->size));
+  } else {
+    log_w("OTA partition not found. Writing disabled");
+  }
+  msc_table_sectors = fat_sectors_per_alloc_table(data_sectors, false);
+  total_sectors = data_sectors + msc_table_sectors + 2;
+  if(total_sectors > 0xFF4){
+    log_d("USING FAT16");
+    mcs_is_fat16 = true;
+    total_sectors -= msc_table_sectors;
+    msc_table_sectors = fat_sectors_per_alloc_table(data_sectors, true);
+    total_sectors += msc_table_sectors;
+  } else {
+    log_d("USING FAT12");
+    mcs_is_fat16 = false;
+  }
+  log_d("FAT sector size: %u", DISK_SECTOR_SIZE);
+  log_d("FAT data sectors: %u", data_sectors);
+  log_d("FAT table sectors: %u", msc_table_sectors);
+  log_d("FAT total sectors: %u (%uKB)", total_sectors, (total_sectors * DISK_SECTOR_SIZE) / 1024);
+  return total_sectors;
+}
+
+//setup the ramdisk and add the firmware download file
+static bool msc_update_setup_disk(const char * volume_label, uint32_t serial_number){
+  msc_total_sectors = msc_update_get_required_disk_sectors();
+  uint8_t ram_sectors = msc_table_sectors + 2;
+  msc_ram_disk = (uint8_t*)calloc(ram_sectors, DISK_SECTOR_SIZE);
+  if(!msc_ram_disk){
+    log_e("Failed to allocate RAM Disk: %u bytes", ram_sectors * DISK_SECTOR_SIZE);
+    return false;
+  }
+  fw_start_sector = ram_sectors;
+  fw_end_sector = fw_start_sector;
+  msc_boot = fat_add_boot_sector(msc_ram_disk, msc_total_sectors, msc_table_sectors, fat_file_system_type(mcs_is_fat16), volume_label, serial_number);
+  msc_table = fat_add_table(msc_ram_disk, msc_boot, mcs_is_fat16);
+  //fat_dir_entry_t * label = fat_add_label(msc_ram_disk, volume_label);
+  if(msc_run_partition){
+    fw_entry = fat_add_root_file(msc_ram_disk, 0, "FIRMWARE", "BIN", fw_size, 2, mcs_is_fat16);
+    fw_end_sector = FAT_SIZE_TO_SECTORS(fw_size) + fw_start_sector;
+  }
+  return true;
+}
+
+static void msc_update_delete_disk(){
+  fw_entry = NULL;
+  fw_size = 0;
+  fw_end_sector = 0;
+  fw_start_sector = 0;
+  msc_table = NULL;
+  msc_boot = NULL;
+  msc_table_sectors = 0;
+  msc_total_sectors = 0;
+  msc_run_partition = NULL;
+  msc_ota_partition = NULL;
+  msc_update_state = MSC_UPDATE_IDLE;
+  msc_update_start_sector = 0;
+  msc_update_bytes_written = 0;
+  msc_update_entry = NULL;
+  free(msc_ram_disk);
+  msc_ram_disk = NULL;
+}
+
+//filter out entries to only include BINs in the root folder
+static fat_dir_entry_t * msc_update_get_root_bin_entry(uint8_t index){
+  fat_dir_entry_t * entry = (fat_dir_entry_t *)(msc_ram_disk + ((msc_boot->sectors_per_alloc_table+1) * DISK_SECTOR_SIZE) + (index * sizeof(fat_dir_entry_t)));
+  fat_lfn_entry_t * lfn = (fat_lfn_entry_t*)entry;
+
+  //empty entry
+  if(entry->file_magic == 0){
+    return NULL;
+  }
+  //long file name
+  if(lfn->attr == 0x0F && lfn->type == 0x00 && lfn->first_cluster == 0x0000){
+    return NULL;
+  }
+  //only files marked as archives
+  if(entry->file_attr != FAT_FILE_ATTR_ARCHIVE){
+    return NULL;
+  }
+  //deleted
+  if(entry->file_magic == 0xE5 || entry->file_magic == 0x05){
+    return NULL;
+  }
+  //not bins
+  if(memcmp("BIN", entry->file_extension, 3)){
+    return NULL;
+  }
+  return entry;
+}
+
+//get an empty bin (the host will add an entry for file about to be written with size of zero)
+static fat_dir_entry_t * msc_update_find_new_bin(){
+  for(uint8_t i=16; i;){
+    i--;
+    fat_dir_entry_t * entry = msc_update_get_root_bin_entry(i);
+    if(entry && entry->file_size == 0){
+      return entry;
+    }
+  }
+  return NULL;
+}
+
+//get a bin starting from particular sector
+static fat_dir_entry_t * msc_update_find_bin(uint16_t sector){
+  for(uint8_t i=16; i; ){
+    i--;
+    fat_dir_entry_t * entry = msc_update_get_root_bin_entry(i);
+    if(entry && entry->data_start_sector == (sector - msc_boot->sectors_per_alloc_table)){
+      return entry;
+    }
+  }
+  return NULL;
+}
+
+//write the new data and erase the flash blocks when necessary
+static esp_err_t msc_update_write(const esp_partition_t *partition, uint32_t offset, void *data, size_t size){
+  esp_err_t err = ESP_OK;
+  if((offset & (SPI_FLASH_SEC_SIZE-1)) == 0){
+    err = esp_partition_erase_range(partition, offset, SPI_FLASH_SEC_SIZE);
+    log_v("ERASE[0x%08X]: %s", offset, (err != ESP_OK)?"FAIL":"OK");
+    if(err != ESP_OK){
+      return err;
+    }
+  }
+  return esp_partition_write(partition, offset, data, size);
+}
+
+//called when error was encountered while updating
+static void msc_update_error(){
+  log_e("UPDATE_ERROR: %u", msc_update_bytes_written);
+  arduino_firmware_msc_event_data_t p;
+  p.error.size = msc_update_bytes_written;
+  arduino_usb_event_post(ARDUINO_FIRMWARE_MSC_EVENTS, ARDUINO_FIRMWARE_MSC_ERROR_EVENT, &p, sizeof(arduino_firmware_msc_event_data_t), portMAX_DELAY);
+  msc_update_state = MSC_UPDATE_IDLE;
+  msc_update_entry = NULL;
+  msc_update_bytes_written = 0;
+  msc_update_start_sector = 0;
+}
+
+//called when all firmware bytes have been received
+static void msc_update_end(){
+  log_d("UPDATE_END: %u", msc_update_entry->file_size);
+  msc_update_state = MSC_UPDATE_END;
+  size_t ota_size = get_firmware_size(msc_ota_partition);
+  if(ota_size != msc_update_entry->file_size){
+    log_e("OTA SIZE MISMATCH %u != %u", ota_size, msc_update_entry->file_size);
+    msc_update_error();
+    return;
+  }
+  if(!ota_size || esp_ota_set_boot_partition(msc_ota_partition) != ESP_OK){
+    log_e("ENABLING OTA PARTITION FAILED");
+    msc_update_error();
+    return;
+  }
+  arduino_firmware_msc_event_data_t p;
+  p.end.size = msc_update_entry->file_size;
+  arduino_usb_event_post(ARDUINO_FIRMWARE_MSC_EVENTS, ARDUINO_FIRMWARE_MSC_END_EVENT, &p, sizeof(arduino_firmware_msc_event_data_t), portMAX_DELAY);
+}
+
+static int32_t msc_write(uint32_t lba, uint32_t offset, uint8_t* buffer, uint32_t bufsize){
+  //log_d("lba: %u, offset: %u, bufsize: %u", lba, offset, bufsize);
+  if(lba < fw_start_sector){
+    //write to sectors that are in RAM
+    memcpy(msc_ram_disk + (lba * DISK_SECTOR_SIZE) + offset, buffer, bufsize);
+    if(msc_ota_partition && lba == (fw_start_sector - 1)){
+      //monitor the root folder table
+      if(msc_update_state <= MSC_UPDATE_RUNNING){
+        fat_dir_entry_t * update_entry = msc_update_find_new_bin();
+        if(update_entry) {
+          if(msc_update_entry) {
+            log_v("REPLACING ENTRY");
+          } else {
+            log_v("ASSIGNING ENTRY");
+          }
+          if(msc_update_state <= MSC_UPDATE_STARTING){
+            msc_update_state = MSC_UPDATE_STARTING;
+            msc_update_bytes_written = 0;
+            msc_update_start_sector = 0;
+          }
+          msc_update_entry = update_entry;
+        } else if(msc_update_state == MSC_UPDATE_RUNNING){
+          if(!msc_update_entry && msc_update_start_sector){
+            msc_update_entry = msc_update_find_bin(msc_update_start_sector);
+          }
+          if(msc_update_entry && msc_update_bytes_written >= msc_update_entry->file_size){
+            msc_update_end();
+          }
+        }
+      }
+    }
+  } else if(msc_ota_partition && lba >= msc_update_start_sector){
+    //handle writes to the region where the new firmware will be uploaded
+    arduino_firmware_msc_event_data_t p;
+    if(msc_update_state <= MSC_UPDATE_STARTING && buffer[0] == 0xE9){
+      msc_update_state = MSC_UPDATE_RUNNING;
+      msc_update_start_sector = lba;
+      msc_update_bytes_written = 0;
+      log_d("UPDATE_START: %u (0x%02X)", lba, lba - msc_boot->sectors_per_alloc_table);
+      arduino_usb_event_post(ARDUINO_FIRMWARE_MSC_EVENTS, ARDUINO_FIRMWARE_MSC_START_EVENT, &p, sizeof(arduino_firmware_msc_event_data_t), portMAX_DELAY);
+      if(msc_update_write(msc_ota_partition, ((lba - msc_update_start_sector) * DISK_SECTOR_SIZE) + offset, buffer, bufsize) == ESP_OK){
+        log_v("UPDATE_WRITE: %u %u", ((lba - msc_update_start_sector) * DISK_SECTOR_SIZE) + offset, bufsize);
+        msc_update_bytes_written = ((lba - msc_update_start_sector) * DISK_SECTOR_SIZE) + offset + bufsize;
+        p.write.offset = ((lba - msc_update_start_sector) * DISK_SECTOR_SIZE) + offset;
+        p.write.size = bufsize;
+        arduino_usb_event_post(ARDUINO_FIRMWARE_MSC_EVENTS, ARDUINO_FIRMWARE_MSC_WRITE_EVENT, &p, sizeof(arduino_firmware_msc_event_data_t), portMAX_DELAY);
+      } else {
+        msc_update_error();
+        return 0;
+      }
+    } else if(msc_update_state == MSC_UPDATE_RUNNING){
+      if(msc_update_entry && msc_update_entry->file_size && msc_update_bytes_written < msc_update_entry->file_size && (msc_update_bytes_written + bufsize) >= msc_update_entry->file_size){
+        bufsize = msc_update_entry->file_size - msc_update_bytes_written;
+      }
+      if(msc_update_write(msc_ota_partition, ((lba - msc_update_start_sector) * DISK_SECTOR_SIZE) + offset, buffer, bufsize) == ESP_OK){
+        log_v("UPDATE_WRITE: %u %u", ((lba - msc_update_start_sector) * DISK_SECTOR_SIZE) + offset, bufsize);
+        msc_update_bytes_written = ((lba - msc_update_start_sector) * DISK_SECTOR_SIZE) + offset + bufsize;
+        p.write.offset = ((lba - msc_update_start_sector) * DISK_SECTOR_SIZE) + offset;
+        p.write.size = bufsize;
+        arduino_usb_event_post(ARDUINO_FIRMWARE_MSC_EVENTS, ARDUINO_FIRMWARE_MSC_WRITE_EVENT, &p, sizeof(arduino_firmware_msc_event_data_t), portMAX_DELAY);
+        if(msc_update_entry && msc_update_entry->file_size && msc_update_bytes_written >= msc_update_entry->file_size){
+          msc_update_end();
+        }
+      } else {
+        msc_update_error();
+        return 0;
+      }
+    }
+  }
+  return bufsize;
+}
+
+static int32_t msc_read(uint32_t lba, uint32_t offset, void* buffer, uint32_t bufsize){
+  //log_d("lba: %u, offset: %u, bufsize: %u", lba, offset, bufsize);
+  if(lba < fw_start_sector){
+    memcpy(buffer, msc_ram_disk + (lba * DISK_SECTOR_SIZE) + offset, bufsize);
+  } else if(msc_run_partition && lba < fw_end_sector){
+    //read the currently running firmware
+    if(esp_partition_read(msc_run_partition, ((lba - fw_start_sector) * DISK_SECTOR_SIZE) + offset, buffer, bufsize) != ESP_OK){
+      return 0;
+    }
+  } else {
+    memset(buffer, 0, bufsize);
+  }
+  return bufsize;
+}
+
+static bool msc_start_stop(uint8_t power_condition, bool start, bool load_eject){
+  //log_d("power: %u, start: %u, eject: %u", power_condition, start, load_eject);
+  arduino_firmware_msc_event_data_t p;
+  p.power.power_condition = power_condition;
+  p.power.start = start;
+  p.power.load_eject = load_eject;
+  arduino_usb_event_post(ARDUINO_FIRMWARE_MSC_EVENTS, ARDUINO_FIRMWARE_MSC_POWER_EVENT, &p, sizeof(arduino_firmware_msc_event_data_t), portMAX_DELAY);
+  return true;
+}
+
+static volatile TaskHandle_t msc_task_handle = NULL;
+static void msc_task(void *pvParameters){
+  for (;;) {
+    if(msc_update_state == MSC_UPDATE_END){
+      delay(100);
+      esp_restart();
+    }
+    delay(100);
+  }
+  msc_task_handle = NULL;
+  vTaskDelete(NULL);
+}
+
+FirmwareMSC::FirmwareMSC():msc(){}
+
+FirmwareMSC::~FirmwareMSC(){
+  end();
+}
+
+bool FirmwareMSC::begin(){
+  if(msc_ram_disk){
+    return true;
+  }
+
+  if(!msc_update_setup_disk(USB_FW_MSC_VOLUME_NAME, USB_FW_MSC_SERIAL_NUMBER)){
+    return false;
+  }
+
+  if(!msc_task_handle){
+    xTaskCreateUniversal(msc_task, "msc_disk", 1024, NULL, 2, (TaskHandle_t*)&msc_task_handle, 0);
+    if(!msc_task_handle){
+      msc_update_delete_disk();
+      return false;
+    }
+  }
+
+  msc.vendorID(USB_FW_MSC_VENDOR_ID);
+  msc.productID(USB_FW_MSC_PRODUCT_ID);
+  msc.productRevision(USB_FW_MSC_PRODUCT_REVISION);
+  msc.onStartStop(msc_start_stop);
+  msc.onRead(msc_read);
+  msc.onWrite(msc_write);
+  msc.mediaPresent(true);
+  msc.begin(msc_boot->fat12_sector_num, DISK_SECTOR_SIZE);
+  return true;
+}
+
+void FirmwareMSC::end(){
+  msc.end();
+  if(msc_task_handle){
+    vTaskDelete(msc_task_handle);
+    msc_task_handle = NULL;
+  }
+  msc_update_delete_disk();
+}
+
+void FirmwareMSC::onEvent(esp_event_handler_t callback){
+    onEvent(ARDUINO_FIRMWARE_MSC_ANY_EVENT, callback);
+}
+void FirmwareMSC::onEvent(arduino_firmware_msc_event_t event, esp_event_handler_t callback){
+    arduino_usb_event_handler_register_with(ARDUINO_FIRMWARE_MSC_EVENTS, event, callback, this);
+}
+
+#if ARDUINO_USB_MSC_ON_BOOT
+FirmwareMSC MSC_Update;
+#endif
+
+#endif /* CONFIG_USB_MSC_ENABLED */

src/esp32/hardware/cores/esp32/FirmwareMSC.h

@@ -0,0 +1,70 @@
+// Copyright 2015-2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+#include <stdbool.h>
+#include "USBMSC.h"
+
+#if CONFIG_TINYUSB_MSC_ENABLED
+
+#include "esp_event.h"
+
+ESP_EVENT_DECLARE_BASE(ARDUINO_FIRMWARE_MSC_EVENTS);
+
+typedef enum {
+    ARDUINO_FIRMWARE_MSC_ANY_EVENT = ESP_EVENT_ANY_ID,
+    ARDUINO_FIRMWARE_MSC_START_EVENT = 0,
+    ARDUINO_FIRMWARE_MSC_WRITE_EVENT,
+    ARDUINO_FIRMWARE_MSC_END_EVENT,
+    ARDUINO_FIRMWARE_MSC_ERROR_EVENT,
+    ARDUINO_FIRMWARE_MSC_POWER_EVENT,
+    ARDUINO_FIRMWARE_MSC_MAX_EVENT,
+} arduino_firmware_msc_event_t;
+
+typedef union {
+    struct {
+            size_t offset;
+            size_t size;
+    } write;
+    struct {
+            uint8_t power_condition;
+            bool start;
+            bool load_eject;
+    } power;
+    struct {
+            size_t size;
+    } end;
+    struct {
+            size_t size;
+    } error;
+} arduino_firmware_msc_event_data_t;
+
+class FirmwareMSC {
+private:
+  USBMSC msc;
+
+public:
+  FirmwareMSC();
+  ~FirmwareMSC();
+  bool begin();
+  void end();
+  void onEvent(esp_event_handler_t callback);
+  void onEvent(arduino_firmware_msc_event_t event, esp_event_handler_t callback);
+};
+
+#if ARDUINO_USB_MSC_ON_BOOT
+extern FirmwareMSC MSC_Update;
+#endif
+
+#endif /* CONFIG_TINYUSB_MSC_ENABLED */

src/esp32/hardware/cores/esp32/FunctionalInterrupt.cpp

@@ -0,0 +1,44 @@
+/*
+ * FunctionalInterrupt.cpp
+ *
+ *  Created on: 8 jul. 2018
+ *      Author: Herman
+ */
+
+#include "FunctionalInterrupt.h"
+#include "Arduino.h"
+
+typedef void (*voidFuncPtr)(void);
+typedef void (*voidFuncPtrArg)(void*);
+
+extern "C"
+{
+	extern void __attachInterruptFunctionalArg(uint8_t pin, voidFuncPtrArg userFunc, void * arg, int intr_type, bool functional);
+}
+
+void ARDUINO_ISR_ATTR interruptFunctional(void* arg)
+{
+    InterruptArgStructure* localArg = (InterruptArgStructure*)arg;
+	if (localArg->interruptFunction)
+	{
+	  localArg->interruptFunction();
+	}
+}
+
+void attachInterrupt(uint8_t pin, std::function<void(void)> intRoutine, int mode)
+{
+	// use the local interrupt routine which takes the ArgStructure as argument
+	__attachInterruptFunctionalArg (digitalPinToGPIONumber(pin), (voidFuncPtrArg)interruptFunctional, new InterruptArgStructure{intRoutine}, mode, true);
+}
+
+extern "C"
+{
+   void cleanupFunctional(void* arg)
+   {
+	 delete (InterruptArgStructure*)arg;
+   }
+}
+
+
+
+

src/esp32/hardware/cores/esp32/FunctionalInterrupt.h

@@ -0,0 +1,22 @@
+/*
+ * FunctionalInterrupt.h
+ *
+ *  Created on: 8 jul. 2018
+ *      Author: Herman
+ */
+
+#ifndef CORE_CORE_FUNCTIONALINTERRUPT_H_
+#define CORE_CORE_FUNCTIONALINTERRUPT_H_
+
+#include <functional>
+#include <stdint.h>
+
+struct InterruptArgStructure {
+    std::function<void(void)> interruptFunction;
+};
+
+// The extra set of parentheses here prevents macros defined
+// in io_pin_remap.h from applying to this declaration.
+void (attachInterrupt)(uint8_t pin, std::function<void(void)> intRoutine, int mode);
+
+#endif /* CORE_CORE_FUNCTIONALINTERRUPT_H_ */

src/esp32/hardware/cores/esp32/HWCDC.cpp

@@ -0,0 +1,411 @@
+// Copyright 2015-2020 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+#include "USB.h"
+#if CONFIG_IDF_TARGET_ESP32C3 || CONFIG_IDF_TARGET_ESP32S3
+
+#include "esp32-hal.h"
+#include "HWCDC.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/semphr.h"
+#include "freertos/queue.h"
+#include "freertos/ringbuf.h"
+#include "esp_intr_alloc.h"
+#include "soc/periph_defs.h"
+#include "hal/usb_serial_jtag_ll.h"
+
+ESP_EVENT_DEFINE_BASE(ARDUINO_HW_CDC_EVENTS);
+
+static RingbufHandle_t tx_ring_buf = NULL;
+static xQueueHandle rx_queue = NULL;
+static uint8_t rx_data_buf[64] = {0};
+static intr_handle_t intr_handle = NULL;
+static volatile bool initial_empty = false;
+static xSemaphoreHandle tx_lock = NULL;
+
+// workaround for when USB CDC is not connected
+static uint32_t tx_timeout_ms = 0;
+static bool tx_timeout_change_request = false;
+
+static esp_event_loop_handle_t arduino_hw_cdc_event_loop_handle = NULL;
+
+static esp_err_t arduino_hw_cdc_event_post(esp_event_base_t event_base, int32_t event_id, void *event_data, size_t event_data_size, BaseType_t *task_unblocked){
+    if(arduino_hw_cdc_event_loop_handle == NULL){
+        return ESP_FAIL;
+    }
+    return esp_event_isr_post_to(arduino_hw_cdc_event_loop_handle, event_base, event_id, event_data, event_data_size, task_unblocked);
+}
+
+static esp_err_t arduino_hw_cdc_event_handler_register_with(esp_event_base_t event_base, int32_t event_id, esp_event_handler_t event_handler, void *event_handler_arg){
+    if (!arduino_hw_cdc_event_loop_handle) {
+        esp_event_loop_args_t event_task_args = {
+            .queue_size = 5,
+            .task_name = "arduino_hw_cdc_events",
+            .task_priority = 5,
+            .task_stack_size = 2048,
+            .task_core_id = tskNO_AFFINITY
+        };
+        if (esp_event_loop_create(&event_task_args, &arduino_hw_cdc_event_loop_handle) != ESP_OK) {
+            log_e("esp_event_loop_create failed");
+        }
+    }
+    if(arduino_hw_cdc_event_loop_handle == NULL){
+        return ESP_FAIL;
+    }
+    return esp_event_handler_register_with(arduino_hw_cdc_event_loop_handle, event_base, event_id, event_handler, event_handler_arg);
+}
+
+static void hw_cdc_isr_handler(void *arg) {
+    portBASE_TYPE xTaskWoken = 0;
+    uint32_t usbjtag_intr_status = 0;
+    arduino_hw_cdc_event_data_t event = {0};
+    usbjtag_intr_status = usb_serial_jtag_ll_get_intsts_mask();
+
+    if (usbjtag_intr_status & USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY) {
+        // Interrupt tells us the host picked up the data we sent.
+        if (usb_serial_jtag_ll_txfifo_writable() == 1) {
+            // We disable the interrupt here so that the interrupt won't be triggered if there is no data to send.
+            usb_serial_jtag_ll_disable_intr_mask(USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY);
+            if(!initial_empty){
+                initial_empty = true;
+                // First time USB is plugged and the application has not explicitly set TX Timeout, set it to default 100ms.
+                // Otherwise, USB is still unplugged and the timeout will be kept as Zero in order to avoid any delay in the
+                // application whenever it uses write() and the TX Queue gets full.
+                if (!tx_timeout_change_request) {
+                    tx_timeout_ms = 100;
+                }
+                //send event?
+                //ets_printf("CONNECTED\n");
+                arduino_hw_cdc_event_post(ARDUINO_HW_CDC_EVENTS, ARDUINO_HW_CDC_CONNECTED_EVENT, &event, sizeof(arduino_hw_cdc_event_data_t), &xTaskWoken);
+            }
+            size_t queued_size;
+            uint8_t *queued_buff = (uint8_t *)xRingbufferReceiveUpToFromISR(tx_ring_buf, &queued_size, 64);
+            // If the hardware fifo is avaliable, write in it. Otherwise, do nothing.
+            if (queued_buff != NULL) {  //Although tx_queued_bytes may be larger than 0. We may have interrupt before xRingbufferSend() was called.
+                //Copy the queued buffer into the TX FIFO
+                usb_serial_jtag_ll_clr_intsts_mask(USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY);
+                usb_serial_jtag_ll_write_txfifo(queued_buff, queued_size);
+                usb_serial_jtag_ll_txfifo_flush();
+                vRingbufferReturnItemFromISR(tx_ring_buf, queued_buff, &xTaskWoken);
+                usb_serial_jtag_ll_ena_intr_mask(USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY);
+                //send event?
+                //ets_printf("TX:%u\n", queued_size);
+                event.tx.len = queued_size;
+                arduino_hw_cdc_event_post(ARDUINO_HW_CDC_EVENTS, ARDUINO_HW_CDC_TX_EVENT, &event, sizeof(arduino_hw_cdc_event_data_t), &xTaskWoken);
+            }
+        } else {
+            usb_serial_jtag_ll_clr_intsts_mask(USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY);
+        }
+    }
+
+    if (usbjtag_intr_status & USB_SERIAL_JTAG_INTR_SERIAL_OUT_RECV_PKT) {
+        // read rx buffer(max length is 64), and send avaliable data to ringbuffer.
+        // Ensure the rx buffer size is larger than RX_MAX_SIZE.
+        usb_serial_jtag_ll_clr_intsts_mask(USB_SERIAL_JTAG_INTR_SERIAL_OUT_RECV_PKT);
+        uint32_t rx_fifo_len = usb_serial_jtag_ll_read_rxfifo(rx_data_buf, 64);
+        uint32_t i=0;
+        for(i=0; i<rx_fifo_len; i++){
+            if(rx_queue == NULL || !xQueueSendFromISR(rx_queue, rx_data_buf+i, &xTaskWoken)){
+                break;
+            }
+        }
+        //send event?
+        //ets_printf("RX:%u/%u\n", i, rx_fifo_len);
+        event.rx.len = i;
+        arduino_hw_cdc_event_post(ARDUINO_HW_CDC_EVENTS, ARDUINO_HW_CDC_RX_EVENT, &event, sizeof(arduino_hw_cdc_event_data_t), &xTaskWoken);
+    }
+
+    if (usbjtag_intr_status & USB_SERIAL_JTAG_INTR_BUS_RESET) {
+        usb_serial_jtag_ll_clr_intsts_mask(USB_SERIAL_JTAG_INTR_BUS_RESET);
+        initial_empty = false;
+        usb_serial_jtag_ll_ena_intr_mask(USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY);
+        //ets_printf("BUS_RESET\n");
+        arduino_hw_cdc_event_post(ARDUINO_HW_CDC_EVENTS, ARDUINO_HW_CDC_BUS_RESET_EVENT, &event, sizeof(arduino_hw_cdc_event_data_t), &xTaskWoken);
+    }
+
+    if (xTaskWoken == pdTRUE) {
+        portYIELD_FROM_ISR();
+    }
+}
+
+static void ARDUINO_ISR_ATTR cdc0_write_char(char c) {
+    if(xPortInIsrContext()){
+        xRingbufferSendFromISR(tx_ring_buf, (void*) (&c), 1, NULL);
+    } else {
+        xRingbufferSend(tx_ring_buf, (void*) (&c), 1, tx_timeout_ms / portTICK_PERIOD_MS);
+    }
+    usb_serial_jtag_ll_ena_intr_mask(USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY);
+}
+
+HWCDC::HWCDC() {
+
+}
+
+HWCDC::~HWCDC(){
+    end();
+}
+
+HWCDC::operator bool() const
+{
+    return initial_empty;
+}
+
+void HWCDC::onEvent(esp_event_handler_t callback){
+    onEvent(ARDUINO_HW_CDC_ANY_EVENT, callback);
+}
+
+void HWCDC::onEvent(arduino_hw_cdc_event_t event, esp_event_handler_t callback){
+    arduino_hw_cdc_event_handler_register_with(ARDUINO_HW_CDC_EVENTS, event, callback, this);
+}
+
+void HWCDC::begin(unsigned long baud)
+{
+    if(tx_lock == NULL) {
+        tx_lock = xSemaphoreCreateMutex();
+    }
+    //RX Buffer default has 256 bytes if not preset
+    if(rx_queue == NULL) {
+        if (!setRxBufferSize(256)) {
+            log_e("HW CDC RX Buffer error");
+        }
+    }
+    //TX Buffer default has 256 bytes if not preset
+    if (tx_ring_buf == NULL) {
+        if (!setTxBufferSize(256)) {
+            log_e("HW CDC TX Buffer error");
+        }    
+    }
+    usb_serial_jtag_ll_disable_intr_mask(USB_SERIAL_JTAG_LL_INTR_MASK);
+    usb_serial_jtag_ll_clr_intsts_mask(USB_SERIAL_JTAG_LL_INTR_MASK);
+    usb_serial_jtag_ll_ena_intr_mask(USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY | USB_SERIAL_JTAG_INTR_SERIAL_OUT_RECV_PKT | USB_SERIAL_JTAG_INTR_BUS_RESET);
+    if(!intr_handle && esp_intr_alloc(ETS_USB_SERIAL_JTAG_INTR_SOURCE, 0, hw_cdc_isr_handler, NULL, &intr_handle) != ESP_OK){
+        isr_log_e("HW USB CDC failed to init interrupts");
+        end();
+        return;
+    }
+    usb_serial_jtag_ll_txfifo_flush();
+}
+
+void HWCDC::end()
+{
+    //Disable tx/rx interrupt.
+    usb_serial_jtag_ll_disable_intr_mask(USB_SERIAL_JTAG_LL_INTR_MASK);
+    esp_intr_free(intr_handle);
+    intr_handle = NULL;
+    if(tx_lock != NULL) {
+        vSemaphoreDelete(tx_lock);
+        tx_lock = NULL;
+    }
+    setRxBufferSize(0);
+    setTxBufferSize(0);
+    if (arduino_hw_cdc_event_loop_handle) {
+        esp_event_loop_delete(arduino_hw_cdc_event_loop_handle);
+        arduino_hw_cdc_event_loop_handle = NULL;
+    }
+}
+
+void HWCDC::setTxTimeoutMs(uint32_t timeout){
+    tx_timeout_ms = timeout;
+    // it registers that the user has explicitly requested to use a value as TX timeout
+    // used for the workaround with unplugged USB and TX Queue Full that causes a delay on every write()
+    tx_timeout_change_request = true;
+}
+
+/*
+ * WRITING
+*/
+
+size_t HWCDC::setTxBufferSize(size_t tx_queue_len){
+    if(tx_ring_buf){
+        vRingbufferDelete(tx_ring_buf);
+        tx_ring_buf = NULL;
+    }
+    if(!tx_queue_len){
+        return 0;
+    }
+    tx_ring_buf = xRingbufferCreate(tx_queue_len, RINGBUF_TYPE_BYTEBUF);
+    if(!tx_ring_buf){
+        return 0;
+    }
+    return tx_queue_len;
+}
+
+int HWCDC::availableForWrite(void)
+{
+    if(tx_ring_buf == NULL || tx_lock == NULL){
+        return 0;
+    }
+    if(xSemaphoreTake(tx_lock, tx_timeout_ms / portTICK_PERIOD_MS) != pdPASS){
+        return 0;
+    }
+    size_t a = xRingbufferGetCurFreeSize(tx_ring_buf);
+    xSemaphoreGive(tx_lock);
+    return a;
+}
+
+size_t HWCDC::write(const uint8_t *buffer, size_t size)
+{
+    if(buffer == NULL || size == 0 || tx_ring_buf == NULL || tx_lock == NULL){
+        return 0;
+    }
+    if(xSemaphoreTake(tx_lock, tx_timeout_ms / portTICK_PERIOD_MS) != pdPASS){
+        return 0;
+    }
+    size_t max_size = xRingbufferGetMaxItemSize(tx_ring_buf);
+    size_t space = xRingbufferGetCurFreeSize(tx_ring_buf);
+    size_t to_send = size, so_far = 0;
+
+    if(space > size){
+        space = size;
+    }
+    // Non-Blocking method, Sending data to ringbuffer, and handle the data in ISR.
+    if(xRingbufferSend(tx_ring_buf, (void*) (buffer), space, 0) != pdTRUE){
+        size = 0;
+    } else {
+        to_send -= space;
+        so_far += space;
+        // Now trigger the ISR to read data from the ring buffer.
+        usb_serial_jtag_ll_ena_intr_mask(USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY);
+
+        while(to_send){
+            if(max_size > to_send){
+                max_size = to_send;
+            }
+            // Blocking method, Sending data to ringbuffer, and handle the data in ISR.
+            if(xRingbufferSend(tx_ring_buf, (void*) (buffer+so_far), max_size, tx_timeout_ms / portTICK_PERIOD_MS) != pdTRUE){
+                size = so_far;
+                break;
+            }
+            so_far += max_size;
+            to_send -= max_size;
+            // Now trigger the ISR to read data from the ring buffer.
+            usb_serial_jtag_ll_ena_intr_mask(USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY);
+        }
+    }
+    xSemaphoreGive(tx_lock);
+    return size;
+}
+
+size_t HWCDC::write(uint8_t c)
+{
+    return write(&c, 1);
+}
+
+void HWCDC::flush(void)
+{
+    if(tx_ring_buf == NULL || tx_lock == NULL){
+        return;
+    }
+    if(xSemaphoreTake(tx_lock, tx_timeout_ms / portTICK_PERIOD_MS) != pdPASS){
+        return;
+    }
+    UBaseType_t uxItemsWaiting = 0;
+    vRingbufferGetInfo(tx_ring_buf, NULL, NULL, NULL, NULL, &uxItemsWaiting);
+    if(uxItemsWaiting){
+        // Now trigger the ISR to read data from the ring buffer.
+        usb_serial_jtag_ll_ena_intr_mask(USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY);
+    }
+    while(uxItemsWaiting){
+        delay(5);
+        vRingbufferGetInfo(tx_ring_buf, NULL, NULL, NULL, NULL, &uxItemsWaiting);
+    }
+    xSemaphoreGive(tx_lock);
+}
+
+/*
+ * READING
+*/
+
+size_t HWCDC::setRxBufferSize(size_t rx_queue_len){
+    if(rx_queue){
+        vQueueDelete(rx_queue);
+        rx_queue = NULL;
+    }
+    if(!rx_queue_len){
+        return 0;
+    }
+    rx_queue = xQueueCreate(rx_queue_len, sizeof(uint8_t));
+    if(!rx_queue){
+        return 0;
+    }
+    return rx_queue_len;
+}
+
+int HWCDC::available(void)
+{
+    if(rx_queue == NULL){
+        return -1;
+    }
+    return uxQueueMessagesWaiting(rx_queue);
+}
+
+int HWCDC::peek(void)
+{
+    if(rx_queue == NULL){
+        return -1;
+    }
+    uint8_t c;
+    if(xQueuePeek(rx_queue, &c, 0)) {
+        return c;
+    }
+    return -1;
+}
+
+int HWCDC::read(void)
+{
+    if(rx_queue == NULL){
+        return -1;
+    }
+    uint8_t c = 0;
+    if(xQueueReceive(rx_queue, &c, 0)) {
+        return c;
+    }
+    return -1;
+}
+
+size_t HWCDC::read(uint8_t *buffer, size_t size)
+{
+    if(rx_queue == NULL){
+        return -1;
+    }
+    uint8_t c = 0;
+    size_t count = 0;
+    while(count < size && xQueueReceive(rx_queue, &c, 0)){
+        buffer[count++] = c;
+    }
+    return count;
+}
+
+/*
+ * DEBUG
+*/
+
+void HWCDC::setDebugOutput(bool en)
+{
+    if(en) {
+        uartSetDebug(NULL);
+        ets_install_putc1((void (*)(char)) &cdc0_write_char);
+    } else {
+        ets_install_putc1(NULL);
+    }
+}
+
+#if ARDUINO_USB_MODE
+#if ARDUINO_USB_CDC_ON_BOOT//Serial used for USB CDC
+HWCDC Serial;
+#else
+HWCDC USBSerial;
+#endif
+#endif
+
+#endif /* CONFIG_TINYUSB_CDC_ENABLED */

src/esp32/hardware/cores/esp32/HWCDC.h

@@ -0,0 +1,109 @@
+// Copyright 2015-2020 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+#pragma once
+
+#include "sdkconfig.h"
+#if CONFIG_IDF_TARGET_ESP32C3 || CONFIG_IDF_TARGET_ESP32S3
+
+#include <inttypes.h>
+#include "esp_event.h"
+#include "Stream.h"
+
+ESP_EVENT_DECLARE_BASE(ARDUINO_HW_CDC_EVENTS);
+
+typedef enum {
+    ARDUINO_HW_CDC_ANY_EVENT = ESP_EVENT_ANY_ID,
+    ARDUINO_HW_CDC_CONNECTED_EVENT = 0,
+    ARDUINO_HW_CDC_BUS_RESET_EVENT,
+    ARDUINO_HW_CDC_RX_EVENT,
+    ARDUINO_HW_CDC_TX_EVENT,
+    ARDUINO_HW_CDC_MAX_EVENT,
+} arduino_hw_cdc_event_t;
+
+typedef union {
+    struct {
+            size_t len;
+    } rx;
+    struct {
+            size_t len;
+    } tx;
+} arduino_hw_cdc_event_data_t;
+
+class HWCDC: public Stream
+{
+public:
+    HWCDC();
+    ~HWCDC();
+
+    void onEvent(esp_event_handler_t callback);
+    void onEvent(arduino_hw_cdc_event_t event, esp_event_handler_t callback);
+
+    size_t setRxBufferSize(size_t);
+    size_t setTxBufferSize(size_t);
+    void setTxTimeoutMs(uint32_t timeout);
+    void begin(unsigned long baud=0);
+    void end();
+    
+    int available(void);
+    int availableForWrite(void);
+    int peek(void);
+    int read(void);
+    size_t read(uint8_t *buffer, size_t size);
+    size_t write(uint8_t);
+    size_t write(const uint8_t *buffer, size_t size);
+    void flush(void);
+    
+    inline size_t read(char * buffer, size_t size)
+    {
+        return read((uint8_t*) buffer, size);
+    }
+    inline size_t write(const char * buffer, size_t size)
+    {
+        return write((uint8_t*) buffer, size);
+    }
+    inline size_t write(const char * s)
+    {
+        return write((uint8_t*) s, strlen(s));
+    }
+    inline size_t write(unsigned long n)
+    {
+        return write((uint8_t) n);
+    }
+    inline size_t write(long n)
+    {
+        return write((uint8_t) n);
+    }
+    inline size_t write(unsigned int n)
+    {
+        return write((uint8_t) n);
+    }
+    inline size_t write(int n)
+    {
+        return write((uint8_t) n);
+    }
+    operator bool() const;
+    void setDebugOutput(bool);
+    uint32_t baudRate(){return 115200;}
+
+};
+
+#if ARDUINO_USB_MODE
+#if ARDUINO_USB_CDC_ON_BOOT//Serial used for USB CDC
+extern HWCDC Serial;
+#else
+extern HWCDC USBSerial;
+#endif
+#endif
+
+#endif /* CONFIG_IDF_TARGET_ESP32C3 */

src/esp32/hardware/cores/esp32/HardwareSerial.cpp

@@ -0,0 +1,623 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <inttypes.h>
+
+#include "pins_arduino.h"
+#include "io_pin_remap.h"
+#include "HardwareSerial.h"
+#include "soc/soc_caps.h"
+#include "driver/uart.h"
+#include "freertos/queue.h"
+
+#ifndef ARDUINO_SERIAL_EVENT_TASK_STACK_SIZE
+#define ARDUINO_SERIAL_EVENT_TASK_STACK_SIZE 2048
+#endif
+
+#ifndef ARDUINO_SERIAL_EVENT_TASK_PRIORITY
+#define ARDUINO_SERIAL_EVENT_TASK_PRIORITY (configMAX_PRIORITIES-1)
+#endif
+
+#ifndef ARDUINO_SERIAL_EVENT_TASK_RUNNING_CORE
+#define ARDUINO_SERIAL_EVENT_TASK_RUNNING_CORE -1
+#endif
+
+#ifndef SOC_RX0
+#if CONFIG_IDF_TARGET_ESP32
+#define SOC_RX0 3
+#elif CONFIG_IDF_TARGET_ESP32S2 || CONFIG_IDF_TARGET_ESP32S3
+#define SOC_RX0 44
+#elif CONFIG_IDF_TARGET_ESP32C3
+#define SOC_RX0 20
+#endif
+#endif
+
+#ifndef SOC_TX0
+#if CONFIG_IDF_TARGET_ESP32
+#define SOC_TX0 1
+#elif CONFIG_IDF_TARGET_ESP32S2 || CONFIG_IDF_TARGET_ESP32S3
+#define SOC_TX0 43
+#elif CONFIG_IDF_TARGET_ESP32C3
+#define SOC_TX0 21
+#endif
+#endif
+
+void serialEvent(void) __attribute__((weak));
+void serialEvent(void) {}
+
+#if SOC_UART_NUM > 1
+
+#ifndef RX1
+#if CONFIG_IDF_TARGET_ESP32
+#define RX1 9
+#elif CONFIG_IDF_TARGET_ESP32S2
+#define RX1 18
+#elif CONFIG_IDF_TARGET_ESP32C3
+#define RX1 18
+#elif CONFIG_IDF_TARGET_ESP32S3
+#define RX1 15
+#endif
+#endif
+
+#ifndef TX1
+#if CONFIG_IDF_TARGET_ESP32
+#define TX1 10
+#elif CONFIG_IDF_TARGET_ESP32S2
+#define TX1 17
+#elif CONFIG_IDF_TARGET_ESP32C3
+#define TX1 19
+#elif CONFIG_IDF_TARGET_ESP32S3
+#define TX1 16
+#endif
+#endif
+
+void serialEvent1(void) __attribute__((weak));
+void serialEvent1(void) {}
+#endif /* SOC_UART_NUM > 1 */
+
+#if SOC_UART_NUM > 2
+#ifndef RX2
+#if CONFIG_IDF_TARGET_ESP32
+#define RX2 16
+#elif CONFIG_IDF_TARGET_ESP32S3
+#define RX2 19 
+#endif
+#endif
+
+#ifndef TX2
+#if CONFIG_IDF_TARGET_ESP32
+#define TX2 17
+#elif CONFIG_IDF_TARGET_ESP32S3
+#define TX2 20
+#endif
+#endif
+
+void serialEvent2(void) __attribute__((weak));
+void serialEvent2(void) {}
+#endif /* SOC_UART_NUM > 2 */
+
+#if !defined(NO_GLOBAL_INSTANCES) && !defined(NO_GLOBAL_SERIAL)
+#if ARDUINO_USB_CDC_ON_BOOT //Serial used for USB CDC
+HardwareSerial Serial0(0);
+#else
+HardwareSerial Serial(0);
+#endif
+#if SOC_UART_NUM > 1
+HardwareSerial Serial1(1);
+#endif
+#if SOC_UART_NUM > 2
+HardwareSerial Serial2(2);
+#endif
+
+void serialEventRun(void)
+{
+#if ARDUINO_USB_CDC_ON_BOOT //Serial used for USB CDC
+    if(Serial0.available()) serialEvent();
+#else
+    if(Serial.available()) serialEvent();
+#endif
+#if SOC_UART_NUM > 1
+    if(Serial1.available()) serialEvent1();
+#endif
+#if SOC_UART_NUM > 2
+    if(Serial2.available()) serialEvent2();
+#endif
+}
+#endif
+
+#if !CONFIG_DISABLE_HAL_LOCKS
+#define HSERIAL_MUTEX_LOCK()    do {} while (xSemaphoreTake(_lock, portMAX_DELAY) != pdPASS)
+#define HSERIAL_MUTEX_UNLOCK()  xSemaphoreGive(_lock)
+#else
+#define HSERIAL_MUTEX_LOCK()    
+#define HSERIAL_MUTEX_UNLOCK()  
+#endif
+
+HardwareSerial::HardwareSerial(int uart_nr) : 
+_uart_nr(uart_nr), 
+_uart(NULL),
+_rxBufferSize(256),
+_txBufferSize(0), 
+_onReceiveCB(NULL), 
+_onReceiveErrorCB(NULL),
+_onReceiveTimeout(false),
+_rxTimeout(2),
+_rxFIFOFull(0),
+_eventTask(NULL)
+#if !CONFIG_DISABLE_HAL_LOCKS
+    ,_lock(NULL)
+#endif
+,_rxPin(-1) 
+,_txPin(-1)
+,_ctsPin(-1)
+,_rtsPin(-1)
+{
+#if !CONFIG_DISABLE_HAL_LOCKS
+    if(_lock == NULL){
+        _lock = xSemaphoreCreateMutex();
+        if(_lock == NULL){
+            log_e("xSemaphoreCreateMutex failed");
+            return;
+        }
+    }
+#endif
+}
+
+HardwareSerial::~HardwareSerial()
+{
+    end();
+#if !CONFIG_DISABLE_HAL_LOCKS
+    if(_lock != NULL){
+        vSemaphoreDelete(_lock);
+    }
+#endif
+}
+
+
+void HardwareSerial::_createEventTask(void *args)
+{
+    // Creating UART event Task
+    xTaskCreateUniversal(_uartEventTask, "uart_event_task", ARDUINO_SERIAL_EVENT_TASK_STACK_SIZE, this, ARDUINO_SERIAL_EVENT_TASK_PRIORITY, &_eventTask, ARDUINO_SERIAL_EVENT_TASK_RUNNING_CORE);
+    if (_eventTask == NULL) {
+        log_e(" -- UART%d Event Task not Created!", _uart_nr);
+    }
+}
+
+void HardwareSerial::_destroyEventTask(void)
+{
+    if (_eventTask != NULL) {
+        vTaskDelete(_eventTask);
+        _eventTask = NULL;
+    }
+}
+
+void HardwareSerial::onReceiveError(OnReceiveErrorCb function) 
+{
+    HSERIAL_MUTEX_LOCK();
+    // function may be NULL to cancel onReceive() from its respective task 
+    _onReceiveErrorCB = function;
+    // this can be called after Serial.begin(), therefore it shall create the event task
+    if (function != NULL && _uart != NULL && _eventTask == NULL) {
+        _createEventTask(this);
+    }
+    HSERIAL_MUTEX_UNLOCK();
+}
+
+void HardwareSerial::onReceive(OnReceiveCb function, bool onlyOnTimeout)
+{
+    HSERIAL_MUTEX_LOCK();
+    // function may be NULL to cancel onReceive() from its respective task 
+    _onReceiveCB = function;
+
+    // setting the callback to NULL will just disable it
+    if (_onReceiveCB != NULL) {
+        // When Rx timeout is Zero (disabled), there is only one possible option that is callback when FIFO reaches 120 bytes
+        _onReceiveTimeout = _rxTimeout > 0 ? onlyOnTimeout : false;
+
+        // in case that onReceive() shall work only with RX Timeout, FIFO shall be high
+        // this is a work around for an IDF issue with events and low FIFO Full value (< 3)
+        if (_onReceiveTimeout) {
+            uartSetRxFIFOFull(_uart, 120);
+            log_w("OnReceive is set to Timeout only, thus FIFO Full is now 120 bytes.");
+        }
+
+        // this method can be called after Serial.begin(), therefore it shall create the event task
+        if (_uart != NULL && _eventTask == NULL) {
+            _createEventTask(this); // Create event task
+        }
+    }
+    HSERIAL_MUTEX_UNLOCK();
+}
+
+// This function allow the user to define how many bytes will trigger an Interrupt that will copy RX FIFO to the internal RX Ringbuffer
+// ISR will also move data from FIFO to RX Ringbuffer after a RX Timeout defined in HardwareSerial::setRxTimeout(uint8_t symbols_timeout)
+// A low value of FIFO Full bytes will consume more CPU time within the ISR
+// A high value of FIFO Full bytes will make the application wait longer to have byte available for the Stkech in a streaming scenario
+// Both RX FIFO Full and RX Timeout may affect when onReceive() will be called
+bool HardwareSerial::setRxFIFOFull(uint8_t fifoBytes)
+{
+    HSERIAL_MUTEX_LOCK();
+    // in case that onReceive() shall work only with RX Timeout, FIFO shall be high
+    // this is a work around for an IDF issue with events and low FIFO Full value (< 3)
+    if (_onReceiveCB != NULL && _onReceiveTimeout) {
+        fifoBytes = 120;
+        log_w("OnReceive is set to Timeout only, thus FIFO Full is now 120 bytes.");
+    }
+    bool retCode = uartSetRxFIFOFull(_uart, fifoBytes); // Set new timeout
+    if (fifoBytes > 0 && fifoBytes < SOC_UART_FIFO_LEN - 1) _rxFIFOFull = fifoBytes;
+    HSERIAL_MUTEX_UNLOCK();
+    return retCode;
+}
+
+// timout is calculates in time to receive UART symbols at the UART baudrate.
+// the estimation is about 11 bits per symbol (SERIAL_8N1)
+bool HardwareSerial::setRxTimeout(uint8_t symbols_timeout)
+{
+    HSERIAL_MUTEX_LOCK();
+    
+    // Zero disables timeout, thus, onReceive callback will only be called when RX FIFO reaches 120 bytes
+    // Any non-zero value will activate onReceive callback based on UART baudrate with about 11 bits per symbol 
+    _rxTimeout = symbols_timeout;   
+    if (!symbols_timeout) _onReceiveTimeout = false;  // only when RX timeout is disabled, we also must disable this flag 
+
+    bool retCode = uartSetRxTimeout(_uart, _rxTimeout); // Set new timeout
+    
+    HSERIAL_MUTEX_UNLOCK();
+    return retCode;
+}
+
+void HardwareSerial::eventQueueReset()
+{
+    QueueHandle_t uartEventQueue = NULL;
+    if (_uart == NULL) {
+	    return;
+    }
+    uartGetEventQueue(_uart, &uartEventQueue);
+    if (uartEventQueue != NULL) {
+        xQueueReset(uartEventQueue);
+    }
+}
+
+void HardwareSerial::_uartEventTask(void *args)
+{
+    HardwareSerial *uart = (HardwareSerial *)args;
+    uart_event_t event;
+    QueueHandle_t uartEventQueue = NULL;
+    uartGetEventQueue(uart->_uart, &uartEventQueue);
+    if (uartEventQueue != NULL) {
+        for(;;) {
+            //Waiting for UART event.
+            if(xQueueReceive(uartEventQueue, (void * )&event, (portTickType)portMAX_DELAY)) {
+                hardwareSerial_error_t currentErr = UART_NO_ERROR;
+                switch(event.type) {
+                    case UART_DATA:
+                        if(uart->_onReceiveCB && uart->available() > 0 && 
+                            ((uart->_onReceiveTimeout && event.timeout_flag) || !uart->_onReceiveTimeout) ) 
+                                uart->_onReceiveCB();
+                        break;
+                    case UART_FIFO_OVF:
+                        log_w("UART%d FIFO Overflow. Consider adding Hardware Flow Control to your Application.", uart->_uart_nr);
+                        currentErr = UART_FIFO_OVF_ERROR;
+                        break;
+                    case UART_BUFFER_FULL:
+                        log_w("UART%d Buffer Full. Consider increasing your buffer size of your Application.", uart->_uart_nr);
+                        currentErr = UART_BUFFER_FULL_ERROR;
+                        break;
+                    case UART_BREAK:
+                        log_w("UART%d RX break.", uart->_uart_nr);
+                        currentErr = UART_BREAK_ERROR;
+                        break;
+                    case UART_PARITY_ERR:
+                        log_w("UART%d parity error.", uart->_uart_nr);
+                        currentErr = UART_PARITY_ERROR;
+                        break;
+                    case UART_FRAME_ERR:
+                        log_w("UART%d frame error.", uart->_uart_nr);
+                        currentErr = UART_FRAME_ERROR;
+                        break;
+                    default:
+                        log_w("UART%d unknown event type %d.", uart->_uart_nr, event.type);
+                        break;
+                }
+                if (currentErr != UART_NO_ERROR) {
+                    if(uart->_onReceiveErrorCB) uart->_onReceiveErrorCB(currentErr);
+                }
+            }
+        }
+    }
+    vTaskDelete(NULL);
+}
+
+void HardwareSerial::begin(unsigned long baud, uint32_t config, int8_t rxPin, int8_t txPin, bool invert, unsigned long timeout_ms, uint8_t rxfifo_full_thrhd)
+{
+    if(0 > _uart_nr || _uart_nr >= SOC_UART_NUM) {
+        log_e("Serial number is invalid, please use numers from 0 to %u", SOC_UART_NUM - 1);
+        return;
+    }
+
+#if !CONFIG_DISABLE_HAL_LOCKS
+    if(_lock == NULL){
+        log_e("MUTEX Lock failed. Can't begin.");
+        return;
+    }
+#endif
+
+    HSERIAL_MUTEX_LOCK();
+    // First Time or after end() --> set default Pins
+    if (!uartIsDriverInstalled(_uart)) {
+        switch (_uart_nr) {
+            case UART_NUM_0:
+                if (rxPin < 0 && txPin < 0) {
+                    rxPin = SOC_RX0;
+                    txPin = SOC_TX0;
+                }
+            break;
+#if SOC_UART_NUM > 1                   // may save some flash bytes...
+            case UART_NUM_1:
+               if (rxPin < 0 && txPin < 0) {
+                    rxPin = RX1;
+                    txPin = TX1;
+                }
+            break;
+#endif
+#if SOC_UART_NUM > 2                   // may save some flash bytes...
+            case UART_NUM_2:
+               if (rxPin < 0 && txPin < 0) {
+                    rxPin = RX2;
+                    txPin = TX2;
+                }
+            break;
+#endif
+        }
+    }
+
+    // map logical pins to GPIO numbers
+    rxPin = digitalPinToGPIONumber(rxPin);
+    txPin = digitalPinToGPIONumber(txPin);
+
+    if(_uart) {
+        // in this case it is a begin() over a previous begin() - maybe to change baud rate
+        // thus do not disable debug output
+        end(false);
+    }
+
+    // IDF UART driver keeps Pin setting on restarting. Negative Pin number will keep it unmodified.
+    _uart = uartBegin(_uart_nr, baud ? baud : 9600, config, rxPin, txPin, _rxBufferSize, _txBufferSize, invert, rxfifo_full_thrhd);
+    if (!baud) {
+        // using baud rate as zero, forces it to try to detect the current baud rate in place
+        uartStartDetectBaudrate(_uart);
+        time_t startMillis = millis();
+        unsigned long detectedBaudRate = 0;
+        while(millis() - startMillis < timeout_ms && !(detectedBaudRate = uartDetectBaudrate(_uart))) {
+            yield();
+        }
+
+        end(false);
+
+        if(detectedBaudRate) {
+            delay(100); // Give some time...
+            _uart = uartBegin(_uart_nr, detectedBaudRate, config, rxPin, txPin, _rxBufferSize, _txBufferSize, invert, rxfifo_full_thrhd);
+        } else {
+            log_e("Could not detect baudrate. Serial data at the port must be present within the timeout for detection to be possible");
+            _uart = NULL;
+        }
+    }
+    // create a task to deal with Serial Events when, for example, calling begin() twice to change the baudrate,
+    // or when setting the callback before calling begin() 
+    if (_uart != NULL && (_onReceiveCB != NULL || _onReceiveErrorCB != NULL) && _eventTask == NULL) {
+        _createEventTask(this);
+    }
+
+    // Set UART RX timeout
+    uartSetRxTimeout(_uart, _rxTimeout);
+
+    // Set UART FIFO Full depending on the baud rate. 
+    // Lower baud rates will force to emulate byte-by-byte reading
+    // Higher baud rates will keep IDF default of 120 bytes for FIFO FULL Interrupt
+    // It can also be changed by the application at any time 
+    if (!_rxFIFOFull) {    // it has not being changed before calling begin()
+      //  set a default FIFO Full value for the IDF driver
+      uint8_t fifoFull = 1;
+      if (baud > 57600 || (_onReceiveCB != NULL && _onReceiveTimeout)) {
+        fifoFull = 120;
+      }
+      uartSetRxFIFOFull(_uart, fifoFull);
+      _rxFIFOFull = fifoFull;
+    }
+
+    _rxPin = rxPin;
+    _txPin = txPin;
+
+    HSERIAL_MUTEX_UNLOCK();
+}
+
+void HardwareSerial::updateBaudRate(unsigned long baud)
+{
+	uartSetBaudRate(_uart, baud);
+}
+
+void HardwareSerial::end(bool fullyTerminate)
+{
+    // default Serial.end() will completely disable HardwareSerial, 
+    // including any tasks or debug message channel (log_x()) - but not for IDF log messages!
+    if(fullyTerminate) {
+        _onReceiveCB = NULL;
+        _onReceiveErrorCB = NULL;
+        if (uartGetDebug() == _uart_nr) {
+            uartSetDebug(0);
+        }
+
+        _rxFIFOFull = 0; 
+
+        uartDetachPins(_uart, _rxPin, _txPin, _ctsPin, _rtsPin);
+        _rxPin = _txPin = _ctsPin = _rtsPin = -1;
+
+    }
+    delay(10);
+    uartEnd(_uart);
+    _uart = 0;
+    _destroyEventTask();
+}
+
+void HardwareSerial::setDebugOutput(bool en)
+{
+    if(_uart == 0) {
+        return;
+    }
+    if(en) {
+        uartSetDebug(_uart);
+    } else {
+        if(uartGetDebug() == _uart_nr) {
+            uartSetDebug(NULL);
+        }
+    }
+}
+
+int HardwareSerial::available(void)
+{
+    return uartAvailable(_uart);
+}
+int HardwareSerial::availableForWrite(void)
+{
+    return uartAvailableForWrite(_uart);
+}
+
+int HardwareSerial::peek(void)
+{
+    if (available()) {
+        return uartPeek(_uart);
+    }
+    return -1;
+}
+
+int HardwareSerial::read(void)
+{
+    uint8_t c = 0;
+    if (uartReadBytes(_uart, &c, 1, 0) == 1) {
+        return c;
+    } else {
+        return -1;
+    }
+}
+
+// read characters into buffer
+// terminates if size characters have been read, or no further are pending
+// returns the number of characters placed in the buffer
+// the buffer is NOT null terminated.
+size_t HardwareSerial::read(uint8_t *buffer, size_t size)
+{
+    return uartReadBytes(_uart, buffer, size, 0);
+}
+
+// Overrides Stream::readBytes() to be faster using IDF
+size_t HardwareSerial::readBytes(uint8_t *buffer, size_t length)
+{
+    return uartReadBytes(_uart, buffer, length, (uint32_t)getTimeout());
+}
+
+void HardwareSerial::flush(void)
+{
+    uartFlush(_uart);
+}
+
+void HardwareSerial::flush(bool txOnly)
+{
+    uartFlushTxOnly(_uart, txOnly);
+}
+
+size_t HardwareSerial::write(uint8_t c)
+{
+    uartWrite(_uart, c);
+    return 1;
+}
+
+size_t HardwareSerial::write(const uint8_t *buffer, size_t size)
+{
+    uartWriteBuf(_uart, buffer, size);
+    return size;
+}
+uint32_t  HardwareSerial::baudRate()
+
+{
+	return uartGetBaudRate(_uart);
+}
+HardwareSerial::operator bool() const
+{
+    return uartIsDriverInstalled(_uart);
+}
+
+void HardwareSerial::setRxInvert(bool invert)
+{
+    uartSetRxInvert(_uart, invert);
+}
+
+// negative Pin value will keep it unmodified
+bool HardwareSerial::setPins(int8_t rxPin, int8_t txPin, int8_t ctsPin, int8_t rtsPin)
+{
+    if(_uart == NULL) {
+        log_e("setPins() shall be called after begin() - nothing done\n");
+        return false;
+    }
+
+    // map logical pins to GPIO numbers
+    rxPin = digitalPinToGPIONumber(rxPin);
+    txPin = digitalPinToGPIONumber(txPin);
+    ctsPin = digitalPinToGPIONumber(ctsPin);
+    rtsPin = digitalPinToGPIONumber(rtsPin);
+
+    // uartSetPins() checks if pins are valid for each function and for the SoC
+    bool retCode = uartSetPins(_uart, rxPin, txPin, ctsPin, rtsPin);
+    if (retCode) {
+        _txPin = _txPin >= 0 ? txPin : _txPin;
+        _rxPin = _rxPin >= 0 ? rxPin : _rxPin;
+        _rtsPin = _rtsPin >= 0 ? rtsPin : _rtsPin;
+        _ctsPin = _ctsPin >= 0 ? ctsPin : _ctsPin;
+    } else {
+        log_e("Error when setting Serial port Pins. Invalid Pin.\n");
+    }
+    return retCode;
+}
+
+// Enables or disables Hardware Flow Control using RTS and/or CTS pins (must use setAllPins() before)
+bool HardwareSerial::setHwFlowCtrlMode(uint8_t mode, uint8_t threshold)
+{
+    return uartSetHwFlowCtrlMode(_uart, mode, threshold);
+}
+
+// Sets the uart mode in the esp32 uart for use with RS485 modes (HwFlowCtrl must be disabled and RTS pin set)
+bool HardwareSerial::setMode(uint8_t mode)
+{
+    return uartSetMode(_uart, mode);
+}
+
+size_t HardwareSerial::setRxBufferSize(size_t new_size) {
+
+    if (_uart) {
+        log_e("RX Buffer can't be resized when Serial is already running.\n");
+        return 0;
+    }
+
+    if (new_size <= SOC_UART_FIFO_LEN) {
+        log_e("RX Buffer must be higher than %d.\n", SOC_UART_FIFO_LEN);  // ESP32, S2, S3 and C3 means higher than 128
+        return 0;
+    }
+
+    _rxBufferSize = new_size;
+    return _rxBufferSize;
+}
+
+size_t HardwareSerial::setTxBufferSize(size_t new_size) {
+
+    if (_uart) {
+        log_e("TX Buffer can't be resized when Serial is already running.\n");
+        return 0;
+    }
+
+    if (new_size <= SOC_UART_FIFO_LEN) {
+        log_e("TX Buffer must be higher than %d.\n", SOC_UART_FIFO_LEN);  // ESP32, S2, S3 and C3 means higher than 128
+        return 0;
+    }
+
+    _txBufferSize = new_size;
+    return _txBufferSize;
+}

src/esp32/hardware/cores/esp32/HardwareSerial.h

@@ -0,0 +1,216 @@
+/*
+ HardwareSerial.h - Hardware serial library for Wiring
+ Copyright (c) 2006 Nicholas Zambetti.  All right reserved.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+ Modified 28 September 2010 by Mark Sproul
+ Modified 14 August 2012 by Alarus
+ Modified 3 December 2013 by Matthijs Kooijman
+ Modified 18 December 2014 by Ivan Grokhotkov (esp8266 platform support)
+ Modified 31 March 2015 by Markus Sattler (rewrite the code for UART0 + UART1 support in ESP8266)
+ Modified 25 April 2015 by Thomas Flayols (add configuration different from 8N1 in ESP8266)
+ Modified 13 October 2018 by Jeroen Döll (add baudrate detection)
+ Baudrate detection example usage (detection on Serial1):
+   void setup() {
+     Serial.begin(115200);
+     delay(100);
+     Serial.println();
+
+     Serial1.begin(0, SERIAL_8N1, -1, -1, true, 11000UL);  // Passing 0 for baudrate to detect it, the last parameter is a timeout in ms
+
+     unsigned long detectedBaudRate = Serial1.baudRate();
+     if(detectedBaudRate) {
+       Serial.printf("Detected baudrate is %lu\n", detectedBaudRate);
+     } else {
+       Serial.println("No baudrate detected, Serial1 will not work!");
+     }
+   }
+
+ Pay attention: the baudrate returned by baudRate() may be rounded, eg 115200 returns 115201
+ */
+
+#ifndef HardwareSerial_h
+#define HardwareSerial_h
+
+#include <inttypes.h>
+#include <functional>
+#include "Stream.h"
+#include "esp32-hal.h"
+#include "soc/soc_caps.h"
+#include "HWCDC.h"
+
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "freertos/semphr.h"
+
+typedef enum {
+    UART_NO_ERROR,
+    UART_BREAK_ERROR,
+    UART_BUFFER_FULL_ERROR,
+    UART_FIFO_OVF_ERROR,
+    UART_FRAME_ERROR,
+    UART_PARITY_ERROR
+} hardwareSerial_error_t;
+
+typedef std::function<void(void)> OnReceiveCb;
+typedef std::function<void(hardwareSerial_error_t)> OnReceiveErrorCb;
+
+class HardwareSerial: public Stream
+{
+public:
+    HardwareSerial(int uart_nr);
+    ~HardwareSerial();
+
+    // setRxTimeout sets the timeout after which onReceive callback will be called (after receiving data, it waits for this time of UART rx inactivity to call the callback fnc)
+    // param symbols_timeout defines a timeout threshold in uart symbol periods. Setting 0 symbol timeout disables the callback call by timeout.
+    //                       Maximum timeout setting is calculacted automatically by IDF. If set above the maximum, it is ignored and an error is printed on Serial0 (check console).
+    //                       Examples: Maximum for 11 bits symbol is 92 (SERIAL_8N2, SERIAL_8E1, SERIAL_8O1, etc), Maximum for 10 bits symbol is 101 (SERIAL_8N1).
+    //                       For example symbols_timeout=1 defines a timeout equal to transmission time of one symbol (~11 bit) on current baudrate. 
+    //                       For a baudrate of 9600, SERIAL_8N1 (10 bit symbol) and symbols_timeout = 3, the timeout would be 3 / (9600 / 10) = 3.125 ms
+    bool setRxTimeout(uint8_t symbols_timeout);
+
+    // setRxFIFOFull(uint8_t fifoBytes) will set the number of bytes that will trigger UART_INTR_RXFIFO_FULL interrupt and fill up RxRingBuffer
+    // This affects some functions such as Serial::available() and Serial.read() because, in a UART flow of receiving data, Serial internal 
+    // RxRingBuffer will be filled only after these number of bytes arrive or a RX Timeout happens.
+    // This parameter can be set to 1 in order to receive byte by byte, but it will also consume more CPU time as the ISR will be activates often.
+    bool setRxFIFOFull(uint8_t fifoBytes);
+
+    // onReceive will setup a callback that will be called whenever an UART interruption occurs (UART_INTR_RXFIFO_FULL or UART_INTR_RXFIFO_TOUT)
+    // UART_INTR_RXFIFO_FULL interrupt triggers at UART_FULL_THRESH_DEFAULT bytes received (defined as 120 bytes by default in IDF)
+    // UART_INTR_RXFIFO_TOUT interrupt triggers at UART_TOUT_THRESH_DEFAULT symbols passed without any reception (defined as 10 symbos by default in IDF)
+    // onlyOnTimeout parameter will define how onReceive will behave:
+    // Default: true -- The callback will only be called when RX Timeout happens. 
+    //                  Whole stream of bytes will be ready for being read on the callback function at once.
+    //                  This option may lead to Rx Overflow depending on the Rx Buffer Size and number of bytes received in the streaming
+    //         false -- The callback will be called when FIFO reaches 120 bytes and also on RX Timeout.
+    //                  The stream of incommig bytes will be "split" into blocks of 120 bytes on each callback.
+    //                  This option avoid any sort of Rx Overflow, but leaves the UART packet reassembling work to the Application.
+    void onReceive(OnReceiveCb function, bool onlyOnTimeout = false);
+
+    // onReceive will be called on error events (see hardwareSerial_error_t)
+    void onReceiveError(OnReceiveErrorCb function);
+
+    // eventQueueReset clears all events in the queue (the events that trigger onReceive and onReceiveError) - maybe usefull in some use cases
+    void eventQueueReset();
+ 
+    void begin(unsigned long baud, uint32_t config=SERIAL_8N1, int8_t rxPin=-1, int8_t txPin=-1, bool invert=false, unsigned long timeout_ms = 20000UL, uint8_t rxfifo_full_thrhd = 112);
+    void end(bool fullyTerminate = true);
+    void updateBaudRate(unsigned long baud);
+    int available(void);
+    int availableForWrite(void);
+    int peek(void);
+    int read(void);
+    size_t read(uint8_t *buffer, size_t size);
+    inline size_t read(char * buffer, size_t size)
+    {
+        return read((uint8_t*) buffer, size);
+    }
+    // Overrides Stream::readBytes() to be faster using IDF
+    size_t readBytes(uint8_t *buffer, size_t length);
+    size_t readBytes(char *buffer, size_t length)
+    {
+        return readBytes((uint8_t *) buffer, length);
+    }    
+    void flush(void);
+    void flush( bool txOnly);
+    size_t write(uint8_t);
+    size_t write(const uint8_t *buffer, size_t size);
+    inline size_t write(const char * buffer, size_t size)
+    {
+        return write((uint8_t*) buffer, size);
+    }
+    inline size_t write(const char * s)
+    {
+        return write((uint8_t*) s, strlen(s));
+    }
+    inline size_t write(unsigned long n)
+    {
+        return write((uint8_t) n);
+    }
+    inline size_t write(long n)
+    {
+        return write((uint8_t) n);
+    }
+    inline size_t write(unsigned int n)
+    {
+        return write((uint8_t) n);
+    }
+    inline size_t write(int n)
+    {
+        return write((uint8_t) n);
+    }
+    uint32_t baudRate();
+    operator bool() const;
+
+    void setDebugOutput(bool);
+    
+    void setRxInvert(bool);
+
+    // Negative Pin Number will keep it unmodified, thus this function can set individual pins
+    // SetPins shall be called after Serial begin()
+    bool setPins(int8_t rxPin, int8_t txPin, int8_t ctsPin = -1, int8_t rtsPin = -1);
+    // Enables or disables Hardware Flow Control using RTS and/or CTS pins (must use setAllPins() before)
+    bool setHwFlowCtrlMode(uint8_t mode = HW_FLOWCTRL_CTS_RTS, uint8_t threshold = 64);   // 64 is half FIFO Length
+    // Used to set RS485 modes such as UART_MODE_RS485_HALF_DUPLEX for Auto RTS function on ESP32
+    bool setMode(uint8_t mode);
+    size_t setRxBufferSize(size_t new_size);
+    size_t setTxBufferSize(size_t new_size);
+
+protected:
+    int _uart_nr;
+    uart_t* _uart;
+    size_t _rxBufferSize;
+    size_t _txBufferSize;
+    OnReceiveCb _onReceiveCB;
+    OnReceiveErrorCb _onReceiveErrorCB;
+    // _onReceive and _rxTimeout have be consistent when timeout is disabled
+    bool _onReceiveTimeout;
+    uint8_t _rxTimeout, _rxFIFOFull;
+    TaskHandle_t _eventTask;
+#if !CONFIG_DISABLE_HAL_LOCKS
+    SemaphoreHandle_t _lock;
+#endif
+    int8_t _rxPin, _txPin, _ctsPin, _rtsPin;
+
+    void _createEventTask(void *args);
+    void _destroyEventTask(void);
+    static void _uartEventTask(void *args);
+};
+
+extern void serialEventRun(void) __attribute__((weak));
+
+#if !defined(NO_GLOBAL_INSTANCES) && !defined(NO_GLOBAL_SERIAL)
+#ifndef ARDUINO_USB_CDC_ON_BOOT
+#define ARDUINO_USB_CDC_ON_BOOT 0
+#endif
+#if ARDUINO_USB_CDC_ON_BOOT //Serial used for USB CDC
+#if !ARDUINO_USB_MODE
+#include "USB.h"
+#include "USBCDC.h"
+#endif
+extern HardwareSerial Serial0;
+#else
+extern HardwareSerial Serial;
+#endif
+#if SOC_UART_NUM > 1
+extern HardwareSerial Serial1;
+#endif
+#if SOC_UART_NUM > 2
+extern HardwareSerial Serial2;
+#endif
+#endif
+
+#endif // HardwareSerial_h

src/esp32/hardware/cores/esp32/base64.cpp

@@ -0,0 +1,64 @@
+/**
+ * base64.cpp
+ *
+ * Created on: 09.12.2015
+ *
+ * Copyright (c) 2015 Markus Sattler. All rights reserved.
+ * This file is part of the ESP31B core for Arduino.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#include "Arduino.h"
+extern "C" {
+#include "libb64/cdecode.h"
+#include "libb64/cencode.h"
+}
+#include "base64.h"
+
+/**
+ * convert input data to base64
+ * @param data const uint8_t *
+ * @param length size_t
+ * @return String
+ */
+String base64::encode(const uint8_t * data, size_t length)
+{
+    size_t size = base64_encode_expected_len(length) + 1;
+    char * buffer = (char *) malloc(size);
+    if(buffer) {
+        base64_encodestate _state;
+        base64_init_encodestate(&_state);
+        int len = base64_encode_block((const char *) &data[0], length, &buffer[0], &_state);
+        len = base64_encode_blockend((buffer + len), &_state);
+
+        String base64 = String(buffer);
+        free(buffer);
+        return base64;
+    }
+    return String("-FAIL-");
+}
+
+/**
+ * convert input data to base64
+ * @param text const String&
+ * @return String
+ */
+String base64::encode(const String& text)
+{
+    return base64::encode((uint8_t *) text.c_str(), text.length());
+}
+

src/esp32/hardware/cores/esp32/base64.h

@@ -0,0 +1,13 @@
+#ifndef CORE_BASE64_H_
+#define CORE_BASE64_H_
+
+class base64
+{
+public:
+    static String encode(const uint8_t * data, size_t length);
+    static String encode(const String& text);
+private:
+};
+
+
+#endif /* CORE_BASE64_H_ */

src/esp32/hardware/cores/esp32/binary.h

@@ -0,0 +1,534 @@
+/*
+ binary.h - Definitions for binary constants
+ Copyright (c) 2006 David A. Mellis.  All right reserved.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#ifndef Binary_h
+#define Binary_h
+
+#define B0 0
+#define B00 0
+#define B000 0
+#define B0000 0
+#define B00000 0
+#define B000000 0
+#define B0000000 0
+#define B00000000 0
+#define B1 1
+#define B01 1
+#define B001 1
+#define B0001 1
+#define B00001 1
+#define B000001 1
+#define B0000001 1
+#define B00000001 1
+#define B10 2
+#define B010 2
+#define B0010 2
+#define B00010 2
+#define B000010 2
+#define B0000010 2
+#define B00000010 2
+#define B11 3
+#define B011 3
+#define B0011 3
+#define B00011 3
+#define B000011 3
+#define B0000011 3
+#define B00000011 3
+#define B100 4
+#define B0100 4
+#define B00100 4
+#define B000100 4
+#define B0000100 4
+#define B00000100 4
+#define B101 5
+#define B0101 5
+#define B00101 5
+#define B000101 5
+#define B0000101 5
+#define B00000101 5
+#define B110 6
+#define B0110 6
+#define B00110 6
+#define B000110 6
+#define B0000110 6
+#define B00000110 6
+#define B111 7
+#define B0111 7
+#define B00111 7
+#define B000111 7
+#define B0000111 7
+#define B00000111 7
+#define B1000 8
+#define B01000 8
+#define B001000 8
+#define B0001000 8
+#define B00001000 8
+#define B1001 9
+#define B01001 9
+#define B001001 9
+#define B0001001 9
+#define B00001001 9
+#define B1010 10
+#define B01010 10
+#define B001010 10
+#define B0001010 10
+#define B00001010 10
+#define B1011 11
+#define B01011 11
+#define B001011 11
+#define B0001011 11
+#define B00001011 11
+#define B1100 12
+#define B01100 12
+#define B001100 12
+#define B0001100 12
+#define B00001100 12
+#define B1101 13
+#define B01101 13
+#define B001101 13
+#define B0001101 13
+#define B00001101 13
+#define B1110 14
+#define B01110 14
+#define B001110 14
+#define B0001110 14
+#define B00001110 14
+#define B1111 15
+#define B01111 15
+#define B001111 15
+#define B0001111 15
+#define B00001111 15
+#define B10000 16
+#define B010000 16
+#define B0010000 16
+#define B00010000 16
+#define B10001 17
+#define B010001 17
+#define B0010001 17
+#define B00010001 17
+#define B10010 18
+#define B010010 18
+#define B0010010 18
+#define B00010010 18
+#define B10011 19
+#define B010011 19
+#define B0010011 19
+#define B00010011 19
+#define B10100 20
+#define B010100 20
+#define B0010100 20
+#define B00010100 20
+#define B10101 21
+#define B010101 21
+#define B0010101 21
+#define B00010101 21
+#define B10110 22
+#define B010110 22
+#define B0010110 22
+#define B00010110 22
+#define B10111 23
+#define B010111 23
+#define B0010111 23
+#define B00010111 23
+#define B11000 24
+#define B011000 24
+#define B0011000 24
+#define B00011000 24
+#define B11001 25
+#define B011001 25
+#define B0011001 25
+#define B00011001 25
+#define B11010 26
+#define B011010 26
+#define B0011010 26
+#define B00011010 26
+#define B11011 27
+#define B011011 27
+#define B0011011 27
+#define B00011011 27
+#define B11100 28
+#define B011100 28
+#define B0011100 28
+#define B00011100 28
+#define B11101 29
+#define B011101 29
+#define B0011101 29
+#define B00011101 29
+#define B11110 30
+#define B011110 30
+#define B0011110 30
+#define B00011110 30
+#define B11111 31
+#define B011111 31
+#define B0011111 31
+#define B00011111 31
+#define B100000 32
+#define B0100000 32
+#define B00100000 32
+#define B100001 33
+#define B0100001 33
+#define B00100001 33
+#define B100010 34
+#define B0100010 34
+#define B00100010 34
+#define B100011 35
+#define B0100011 35
+#define B00100011 35
+#define B100100 36
+#define B0100100 36
+#define B00100100 36
+#define B100101 37
+#define B0100101 37
+#define B00100101 37
+#define B100110 38
+#define B0100110 38
+#define B00100110 38
+#define B100111 39
+#define B0100111 39
+#define B00100111 39
+#define B101000 40
+#define B0101000 40
+#define B00101000 40
+#define B101001 41
+#define B0101001 41
+#define B00101001 41
+#define B101010 42
+#define B0101010 42
+#define B00101010 42
+#define B101011 43
+#define B0101011 43
+#define B00101011 43
+#define B101100 44
+#define B0101100 44
+#define B00101100 44
+#define B101101 45
+#define B0101101 45
+#define B00101101 45
+#define B101110 46
+#define B0101110 46
+#define B00101110 46
+#define B101111 47
+#define B0101111 47
+#define B00101111 47
+#define B110000 48
+#define B0110000 48
+#define B00110000 48
+#define B110001 49
+#define B0110001 49
+#define B00110001 49
+#define B110010 50
+#define B0110010 50
+#define B00110010 50
+#define B110011 51
+#define B0110011 51
+#define B00110011 51
+#define B110100 52
+#define B0110100 52
+#define B00110100 52
+#define B110101 53
+#define B0110101 53
+#define B00110101 53
+#define B110110 54
+#define B0110110 54
+#define B00110110 54
+#define B110111 55
+#define B0110111 55
+#define B00110111 55
+#define B111000 56
+#define B0111000 56
+#define B00111000 56
+#define B111001 57
+#define B0111001 57
+#define B00111001 57
+#define B111010 58
+#define B0111010 58
+#define B00111010 58
+#define B111011 59
+#define B0111011 59
+#define B00111011 59
+#define B111100 60
+#define B0111100 60
+#define B00111100 60
+#define B111101 61
+#define B0111101 61
+#define B00111101 61
+#define B111110 62
+#define B0111110 62
+#define B00111110 62
+#define B111111 63
+#define B0111111 63
+#define B00111111 63
+#define B1000000 64
+#define B01000000 64
+#define B1000001 65
+#define B01000001 65
+#define B1000010 66
+#define B01000010 66
+#define B1000011 67
+#define B01000011 67
+#define B1000100 68
+#define B01000100 68
+#define B1000101 69
+#define B01000101 69
+#define B1000110 70
+#define B01000110 70
+#define B1000111 71
+#define B01000111 71
+#define B1001000 72
+#define B01001000 72
+#define B1001001 73
+#define B01001001 73
+#define B1001010 74
+#define B01001010 74
+#define B1001011 75
+#define B01001011 75
+#define B1001100 76
+#define B01001100 76
+#define B1001101 77
+#define B01001101 77
+#define B1001110 78
+#define B01001110 78
+#define B1001111 79
+#define B01001111 79
+#define B1010000 80
+#define B01010000 80
+#define B1010001 81
+#define B01010001 81
+#define B1010010 82
+#define B01010010 82
+#define B1010011 83
+#define B01010011 83
+#define B1010100 84
+#define B01010100 84
+#define B1010101 85
+#define B01010101 85
+#define B1010110 86
+#define B01010110 86
+#define B1010111 87
+#define B01010111 87
+#define B1011000 88
+#define B01011000 88
+#define B1011001 89
+#define B01011001 89
+#define B1011010 90
+#define B01011010 90
+#define B1011011 91
+#define B01011011 91
+#define B1011100 92
+#define B01011100 92
+#define B1011101 93
+#define B01011101 93
+#define B1011110 94
+#define B01011110 94
+#define B1011111 95
+#define B01011111 95
+#define B1100000 96
+#define B01100000 96
+#define B1100001 97
+#define B01100001 97
+#define B1100010 98
+#define B01100010 98
+#define B1100011 99
+#define B01100011 99
+#define B1100100 100
+#define B01100100 100
+#define B1100101 101
+#define B01100101 101
+#define B1100110 102
+#define B01100110 102
+#define B1100111 103
+#define B01100111 103
+#define B1101000 104
+#define B01101000 104
+#define B1101001 105
+#define B01101001 105
+#define B1101010 106
+#define B01101010 106
+#define B1101011 107
+#define B01101011 107
+#define B1101100 108
+#define B01101100 108
+#define B1101101 109
+#define B01101101 109
+#define B1101110 110
+#define B01101110 110
+#define B1101111 111
+#define B01101111 111
+#define B1110000 112
+#define B01110000 112
+#define B1110001 113
+#define B01110001 113
+#define B1110010 114
+#define B01110010 114
+#define B1110011 115
+#define B01110011 115
+#define B1110100 116
+#define B01110100 116
+#define B1110101 117
+#define B01110101 117
+#define B1110110 118
+#define B01110110 118
+#define B1110111 119
+#define B01110111 119
+#define B1111000 120
+#define B01111000 120
+#define B1111001 121
+#define B01111001 121
+#define B1111010 122
+#define B01111010 122
+#define B1111011 123
+#define B01111011 123
+#define B1111100 124
+#define B01111100 124
+#define B1111101 125
+#define B01111101 125
+#define B1111110 126
+#define B01111110 126
+#define B1111111 127
+#define B01111111 127
+#define B10000000 128
+#define B10000001 129
+#define B10000010 130
+#define B10000011 131
+#define B10000100 132
+#define B10000101 133
+#define B10000110 134
+#define B10000111 135
+#define B10001000 136
+#define B10001001 137
+#define B10001010 138
+#define B10001011 139
+#define B10001100 140
+#define B10001101 141
+#define B10001110 142
+#define B10001111 143
+#define B10010000 144
+#define B10010001 145
+#define B10010010 146
+#define B10010011 147
+#define B10010100 148
+#define B10010101 149
+#define B10010110 150
+#define B10010111 151
+#define B10011000 152
+#define B10011001 153
+#define B10011010 154
+#define B10011011 155
+#define B10011100 156
+#define B10011101 157
+#define B10011110 158
+#define B10011111 159
+#define B10100000 160
+#define B10100001 161
+#define B10100010 162
+#define B10100011 163
+#define B10100100 164
+#define B10100101 165
+#define B10100110 166
+#define B10100111 167
+#define B10101000 168
+#define B10101001 169
+#define B10101010 170
+#define B10101011 171
+#define B10101100 172
+#define B10101101 173
+#define B10101110 174
+#define B10101111 175
+#define B10110000 176
+#define B10110001 177
+#define B10110010 178
+#define B10110011 179
+#define B10110100 180
+#define B10110101 181
+#define B10110110 182
+#define B10110111 183
+#define B10111000 184
+#define B10111001 185
+#define B10111010 186
+#define B10111011 187
+#define B10111100 188
+#define B10111101 189
+#define B10111110 190
+#define B10111111 191
+#define B11000000 192
+#define B11000001 193
+#define B11000010 194
+#define B11000011 195
+#define B11000100 196
+#define B11000101 197
+#define B11000110 198
+#define B11000111 199
+#define B11001000 200
+#define B11001001 201
+#define B11001010 202
+#define B11001011 203
+#define B11001100 204
+#define B11001101 205
+#define B11001110 206
+#define B11001111 207
+#define B11010000 208
+#define B11010001 209
+#define B11010010 210
+#define B11010011 211
+#define B11010100 212
+#define B11010101 213
+#define B11010110 214
+#define B11010111 215
+#define B11011000 216
+#define B11011001 217
+#define B11011010 218
+#define B11011011 219
+#define B11011100 220
+#define B11011101 221
+#define B11011110 222
+#define B11011111 223
+#define B11100000 224
+#define B11100001 225
+#define B11100010 226
+#define B11100011 227
+#define B11100100 228
+#define B11100101 229
+#define B11100110 230
+#define B11100111 231
+#define B11101000 232
+#define B11101001 233
+#define B11101010 234
+#define B11101011 235
+#define B11101100 236
+#define B11101101 237
+#define B11101110 238
+#define B11101111 239
+#define B11110000 240
+#define B11110001 241
+#define B11110010 242
+#define B11110011 243
+#define B11110100 244
+#define B11110101 245
+#define B11110110 246
+#define B11110111 247
+#define B11111000 248
+#define B11111001 249
+#define B11111010 250
+#define B11111011 251
+#define B11111100 252
+#define B11111101 253
+#define B11111110 254
+#define B11111111 255
+
+#endif

src/esp32/hardware/cores/esp32/cbuf.cpp

@@ -0,0 +1,196 @@
+/*
+ cbuf.cpp - Circular buffer implementation
+ Copyright (c) 2014 Ivan Grokhotkov. All rights reserved.
+ This file is part of the esp8266 core for Arduino environment.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include "cbuf.h"
+
+cbuf::cbuf(size_t size) :
+    next(NULL), _size(size+1), _buf(new char[size+1]), _bufend(_buf + size + 1), _begin(_buf), _end(_begin)
+{
+}
+
+cbuf::~cbuf()
+{
+    delete[] _buf;
+}
+
+size_t cbuf::resizeAdd(size_t addSize)
+{
+    return resize(_size + addSize);
+}
+
+size_t cbuf::resize(size_t newSize)
+{
+
+    size_t bytes_available = available();
+    newSize += 1;
+    // not lose any data
+    // if data can be lost use remove or flush before resize
+    if((newSize < bytes_available) || (newSize == _size)) {
+        return _size;
+    }
+
+    char *newbuf = new char[newSize];
+    char *oldbuf = _buf;
+
+    if(!newbuf) {
+        return _size;
+    }
+
+    if(_buf) {
+        read(newbuf, bytes_available);
+        memset((newbuf + bytes_available), 0x00, (newSize - bytes_available));
+    }
+
+    _begin = newbuf;
+    _end = newbuf + bytes_available;
+    _bufend = newbuf + newSize;
+    _size = newSize;
+
+    _buf = newbuf;
+    delete[] oldbuf;
+
+    return _size;
+}
+
+size_t cbuf::available() const
+{
+    if(_end >= _begin) {
+        return _end - _begin;
+    }
+    return _size - (_begin - _end);
+}
+
+size_t cbuf::size()
+{
+    return _size;
+}
+
+size_t cbuf::room() const
+{
+    if(_end >= _begin) {
+        return _size - (_end - _begin) - 1;
+    }
+    return _begin - _end - 1;
+}
+
+int cbuf::peek()
+{
+    if(empty()) {
+        return -1;
+    }
+
+    return static_cast<int>(*_begin);
+}
+
+size_t cbuf::peek(char *dst, size_t size)
+{
+    size_t bytes_available = available();
+    size_t size_to_read = (size < bytes_available) ? size : bytes_available;
+    size_t size_read = size_to_read;
+    char * begin = _begin;
+    if(_end < _begin && size_to_read > (size_t) (_bufend - _begin)) {
+        size_t top_size = _bufend - _begin;
+        memcpy(dst, _begin, top_size);
+        begin = _buf;
+        size_to_read -= top_size;
+        dst += top_size;
+    }
+    memcpy(dst, begin, size_to_read);
+    return size_read;
+}
+
+int cbuf::read()
+{
+    if(empty()) {
+        return -1;
+    }
+
+    char result = *_begin;
+    _begin = wrap_if_bufend(_begin + 1);
+    return static_cast<int>(result);
+}
+
+size_t cbuf::read(char* dst, size_t size)
+{
+    size_t bytes_available = available();
+    size_t size_to_read = (size < bytes_available) ? size : bytes_available;
+    size_t size_read = size_to_read;
+    if(_end < _begin && size_to_read > (size_t) (_bufend - _begin)) {
+        size_t top_size = _bufend - _begin;
+        memcpy(dst, _begin, top_size);
+        _begin = _buf;
+        size_to_read -= top_size;
+        dst += top_size;
+    }
+    memcpy(dst, _begin, size_to_read);
+    _begin = wrap_if_bufend(_begin + size_to_read);
+    return size_read;
+}
+
+size_t cbuf::write(char c)
+{
+    if(full()) {
+        return 0;
+    }
+
+    *_end = c;
+    _end = wrap_if_bufend(_end + 1);
+    return 1;
+}
+
+size_t cbuf::write(const char* src, size_t size)
+{
+    size_t bytes_available = room();
+    size_t size_to_write = (size < bytes_available) ? size : bytes_available;
+    size_t size_written = size_to_write;
+    if(_end >= _begin && size_to_write > (size_t) (_bufend - _end)) {
+        size_t top_size = _bufend - _end;
+        memcpy(_end, src, top_size);
+        _end = _buf;
+        size_to_write -= top_size;
+        src += top_size;
+    }
+    memcpy(_end, src, size_to_write);
+    _end = wrap_if_bufend(_end + size_to_write);
+    return size_written;
+}
+
+void cbuf::flush()
+{
+    _begin = _buf;
+    _end = _buf;
+}
+
+size_t cbuf::remove(size_t size)
+{
+    size_t bytes_available = available();
+    if(size >= bytes_available) {
+        flush();
+        return 0;
+    }
+    size_t size_to_remove = (size < bytes_available) ? size : bytes_available;
+    if(_end < _begin && size_to_remove > (size_t) (_bufend - _begin)) {
+        size_t top_size = _bufend - _begin;
+        _begin = _buf;
+        size_to_remove -= top_size;
+    }
+    _begin = wrap_if_bufend(_begin + size_to_remove);
+    return available();
+}

src/esp32/hardware/cores/esp32/cbuf.h

@@ -0,0 +1,79 @@
+/*
+ cbuf.h - Circular buffer implementation
+ Copyright (c) 2014 Ivan Grokhotkov. All rights reserved.
+ This file is part of the esp8266 core for Arduino environment.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#ifndef __cbuf_h
+#define __cbuf_h
+
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
+class cbuf
+{
+public:
+    cbuf(size_t size);
+    ~cbuf();
+
+    size_t resizeAdd(size_t addSize);
+    size_t resize(size_t newSize);
+    size_t available() const;
+    size_t size();
+
+    size_t room() const;
+
+    inline bool empty() const
+    {
+        return _begin == _end;
+    }
+
+    inline bool full() const
+    {
+        return wrap_if_bufend(_end + 1) == _begin;
+    }
+
+    int peek();
+    size_t peek(char *dst, size_t size);
+
+    int read();
+    size_t read(char* dst, size_t size);
+
+    size_t write(char c);
+    size_t write(const char* src, size_t size);
+
+    void flush();
+    size_t remove(size_t size);
+
+    cbuf *next;
+
+protected:
+    inline char* wrap_if_bufend(char* ptr) const
+    {
+        return (ptr == _bufend) ? _buf : ptr;
+    }
+
+    size_t _size;
+    char* _buf;
+    const char* _bufend;
+    char* _begin;
+    char* _end;
+
+};
+
+#endif//__cbuf_h

src/esp32/hardware/cores/esp32/core_version.h

@@ -0,0 +1,4 @@
+#define ARDUINO_ESP32_GIT_VER 0x725146d1
+#define ARDUINO_ESP32_GIT_DESC 2.0.12
+#define ARDUINO_ESP32_RELEASE_2_0_12
+#define ARDUINO_ESP32_RELEASE "2_0_12"

src/esp32/hardware/cores/esp32/esp32-hal-adc.c

@@ -0,0 +1,281 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "esp32-hal-adc.h"
+#include "driver/adc.h"
+#include "esp_adc_cal.h"
+
+#if SOC_DAC_SUPPORTED           //ESP32, ESP32S2
+#include "soc/dac_channel.h"
+#include "soc/sens_reg.h"
+#include "soc/rtc_io_reg.h"
+#endif
+
+#define DEFAULT_VREF    1100
+
+static uint8_t __analogAttenuation = 3;//11db
+static uint8_t __analogWidth = ADC_WIDTH_MAX - 1; //3 for ESP32/ESP32C3; 4 for ESP32S2
+static uint8_t __analogReturnedWidth = SOC_ADC_MAX_BITWIDTH; //12 for ESP32/ESP32C3; 13 for ESP32S2
+static uint8_t __analogClockDiv = 1;
+static adc_attenuation_t __pin_attenuation[SOC_GPIO_PIN_COUNT];
+
+static uint16_t __analogVRef = 0;
+#if CONFIG_IDF_TARGET_ESP32
+static uint8_t __analogVRefPin = 0;
+#endif
+
+static inline uint16_t mapResolution(uint16_t value)
+{
+    uint8_t from = __analogWidth + 9;
+    if (from == __analogReturnedWidth) {
+        return value;
+    }
+    if (from > __analogReturnedWidth) {
+        return value >> (from  - __analogReturnedWidth);
+    }
+    return value << (__analogReturnedWidth - from);
+}
+
+void __analogSetClockDiv(uint8_t clockDiv){
+    if(!clockDiv){
+        clockDiv = 1;
+    }
+    __analogClockDiv = clockDiv;
+#if CONFIG_IDF_TARGET_ESP32 || CONFIG_IDF_TARGET_ESP32S2
+    adc_set_clk_div(__analogClockDiv);
+#endif
+}
+
+void __analogSetAttenuation(adc_attenuation_t attenuation)
+{
+    __analogAttenuation = attenuation & 3;
+}
+
+#if CONFIG_IDF_TARGET_ESP32
+void __analogSetWidth(uint8_t bits){
+    if(bits < 9){
+        bits = 9;
+    } else if(bits > 12){
+        bits = 12;
+    }
+    __analogWidth = bits - 9;
+    adc1_config_width(__analogWidth);
+}
+#endif
+
+void __analogInit(){
+    static bool initialized = false;
+    if(initialized){
+        return;
+    }
+    initialized = true;
+    __analogSetClockDiv(__analogClockDiv);
+#if CONFIG_IDF_TARGET_ESP32
+    __analogSetWidth(__analogWidth + 9);//in bits
+#endif
+    for(int i=0; i<SOC_GPIO_PIN_COUNT; i++){
+        __pin_attenuation[i] = ADC_ATTENDB_MAX;
+    }
+}
+
+void __analogSetPinAttenuation(uint8_t pin, adc_attenuation_t attenuation)
+{
+    int8_t channel = digitalPinToAnalogChannel(pin);
+    if(channel < 0 || attenuation > 3){
+        return ;
+    }
+    if(channel > (SOC_ADC_MAX_CHANNEL_NUM - 1)){
+        adc2_config_channel_atten(channel - SOC_ADC_MAX_CHANNEL_NUM, attenuation);
+    } else {
+        adc1_config_channel_atten(channel, attenuation);
+    }
+    __analogInit();
+    if((__pin_attenuation[pin] != ADC_ATTENDB_MAX) || (attenuation != __analogAttenuation)){
+        __pin_attenuation[pin] = attenuation;
+    }
+}
+
+bool __adcAttachPin(uint8_t pin){
+    int8_t channel = digitalPinToAnalogChannel(pin);
+    if(channel < 0){
+        log_e("Pin %u is not ADC pin!", pin);
+        return false;
+    }
+    __analogInit();
+    int8_t pad = digitalPinToTouchChannel(pin);
+    if(pad >= 0){
+#if CONFIG_IDF_TARGET_ESP32
+        uint32_t touch = READ_PERI_REG(SENS_SAR_TOUCH_ENABLE_REG);
+        if(touch & (1 << pad)){
+            touch &= ~((1 << (pad + SENS_TOUCH_PAD_OUTEN2_S))
+                    | (1 << (pad + SENS_TOUCH_PAD_OUTEN1_S))
+                    | (1 << (pad + SENS_TOUCH_PAD_WORKEN_S)));
+            WRITE_PERI_REG(SENS_SAR_TOUCH_ENABLE_REG, touch);
+        }
+#endif
+    }
+#if SOC_DAC_SUPPORTED
+    else if(pin == DAC_CHANNEL_1_GPIO_NUM){
+        CLEAR_PERI_REG_MASK(RTC_IO_PAD_DAC1_REG, RTC_IO_PDAC1_XPD_DAC | RTC_IO_PDAC1_DAC_XPD_FORCE);//stop dac1
+    } else if(pin == DAC_CHANNEL_2_GPIO_NUM){
+        CLEAR_PERI_REG_MASK(RTC_IO_PAD_DAC2_REG, RTC_IO_PDAC2_XPD_DAC | RTC_IO_PDAC2_DAC_XPD_FORCE);//stop dac2
+    }
+#endif
+
+    pinMode(pin, ANALOG);
+    __analogSetPinAttenuation(pin, (__pin_attenuation[pin] != ADC_ATTENDB_MAX)?__pin_attenuation[pin]:__analogAttenuation);
+    return true;
+}
+
+void __analogReadResolution(uint8_t bits)
+{
+    if(!bits || bits > 16){
+        return;
+    }
+    __analogReturnedWidth = bits;
+#if CONFIG_IDF_TARGET_ESP32
+    __analogSetWidth(bits);         // hadware from 9 to 12
+#endif
+}
+
+uint16_t __analogRead(uint8_t pin)
+{
+    int8_t channel = digitalPinToAnalogChannel(pin);
+    int value = 0;
+    esp_err_t r = ESP_OK;
+    if(channel < 0){
+        log_e("Pin %u is not ADC pin!", pin);
+        return value;
+    }
+    __adcAttachPin(pin);
+    if(channel > (SOC_ADC_MAX_CHANNEL_NUM - 1)){
+        channel -= SOC_ADC_MAX_CHANNEL_NUM;
+        r = adc2_get_raw( channel, __analogWidth, &value);
+        if ( r == ESP_OK ) {
+            return mapResolution(value);
+        } else if ( r == ESP_ERR_INVALID_STATE ) {
+            log_e("GPIO%u: %s: ADC2 not initialized yet.", pin, esp_err_to_name(r));
+        } else if ( r == ESP_ERR_TIMEOUT ) {
+            log_e("GPIO%u: %s: ADC2 is in use by Wi-Fi. Please see https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/peripherals/adc.html#adc-limitations for more info", pin, esp_err_to_name(r));
+        } else {
+            log_e("GPIO%u: %s", pin, esp_err_to_name(r));
+        }
+    } else {
+        value = adc1_get_raw(channel);
+        return mapResolution(value);
+    }
+    return mapResolution(value);
+}
+
+uint32_t __analogReadMilliVolts(uint8_t pin){
+    int8_t channel = digitalPinToAnalogChannel(pin);
+    if(channel < 0){
+        log_e("Pin %u is not ADC pin!", pin);
+        return 0;
+    }
+
+    if(!__analogVRef){
+        if (esp_adc_cal_check_efuse(ESP_ADC_CAL_VAL_EFUSE_TP) == ESP_OK) {
+            log_d("eFuse Two Point: Supported");
+            __analogVRef = DEFAULT_VREF;
+        }
+        if (esp_adc_cal_check_efuse(ESP_ADC_CAL_VAL_EFUSE_VREF) == ESP_OK) {
+            log_d("eFuse Vref: Supported");
+            __analogVRef = DEFAULT_VREF;
+        }
+        if(!__analogVRef){
+            __analogVRef = DEFAULT_VREF;
+
+            #if CONFIG_IDF_TARGET_ESP32
+            if(__analogVRefPin){
+                esp_adc_cal_characteristics_t chars;
+                if(adc_vref_to_gpio(ADC_UNIT_2, __analogVRefPin) == ESP_OK){
+                    __analogVRef = __analogRead(__analogVRefPin);
+                    esp_adc_cal_characterize(1, __analogAttenuation, __analogWidth, DEFAULT_VREF, &chars);
+                    __analogVRef = esp_adc_cal_raw_to_voltage(__analogVRef, &chars);
+                    log_d("Vref to GPIO%u: %u", __analogVRefPin, __analogVRef);
+                }
+            }
+            #endif
+        }
+    }
+    uint8_t unit = 1;
+    if(channel > (SOC_ADC_MAX_CHANNEL_NUM - 1)){
+        unit = 2;
+    }
+
+    uint16_t adc_reading = __analogRead(pin);
+
+    uint8_t atten = __analogAttenuation;
+    if (__pin_attenuation[pin] != ADC_ATTENDB_MAX){
+        atten = __pin_attenuation[pin];
+    }
+
+    esp_adc_cal_characteristics_t chars = {};
+    esp_adc_cal_value_t val_type = esp_adc_cal_characterize(unit, atten, __analogWidth, __analogVRef, &chars);
+
+    static bool print_chars_info = true;
+    if(print_chars_info)
+    {
+        if (val_type == ESP_ADC_CAL_VAL_EFUSE_TP) {
+            log_i("ADC%u: Characterized using Two Point Value: %u\n", unit, chars.vref);
+        } 
+        else if (val_type == ESP_ADC_CAL_VAL_EFUSE_VREF) {
+            log_i("ADC%u: Characterized using eFuse Vref: %u\n", unit, chars.vref);
+        } 
+        #if CONFIG_IDF_TARGET_ESP32
+        else if(__analogVRef != DEFAULT_VREF){
+            log_i("ADC%u: Characterized using Vref to GPIO%u: %u\n", unit, __analogVRefPin, chars.vref);
+        }
+        #endif
+        else {
+            log_i("ADC%u: Characterized using Default Vref: %u\n", unit, chars.vref);
+        }
+        print_chars_info = false;
+    }
+    return esp_adc_cal_raw_to_voltage((uint32_t)adc_reading, &chars);
+}
+
+#if CONFIG_IDF_TARGET_ESP32
+
+void __analogSetVRefPin(uint8_t pin){
+    if(pin <25 || pin > 27){
+        pin = 0;
+    }
+    __analogVRefPin = pin;
+}
+
+int __hallRead()    //hall sensor using idf read
+{
+    pinMode(36, ANALOG);
+    pinMode(39, ANALOG);
+    __analogSetWidth(12);
+    return hall_sensor_read();
+}
+#endif
+
+extern uint16_t analogRead(uint8_t pin) __attribute__ ((weak, alias("__analogRead")));
+extern uint32_t analogReadMilliVolts(uint8_t pin) __attribute__ ((weak, alias("__analogReadMilliVolts")));
+extern void analogReadResolution(uint8_t bits) __attribute__ ((weak, alias("__analogReadResolution")));
+extern void analogSetClockDiv(uint8_t clockDiv) __attribute__ ((weak, alias("__analogSetClockDiv")));
+extern void analogSetAttenuation(adc_attenuation_t attenuation) __attribute__ ((weak, alias("__analogSetAttenuation")));
+extern void analogSetPinAttenuation(uint8_t pin, adc_attenuation_t attenuation) __attribute__ ((weak, alias("__analogSetPinAttenuation")));
+
+extern bool adcAttachPin(uint8_t pin) __attribute__ ((weak, alias("__adcAttachPin")));
+
+#if CONFIG_IDF_TARGET_ESP32
+extern void analogSetVRefPin(uint8_t pin) __attribute__ ((weak, alias("__analogSetVRefPin")));
+extern void analogSetWidth(uint8_t bits) __attribute__ ((weak, alias("__analogSetWidth")));
+extern int hallRead() __attribute__ ((weak, alias("__hallRead")));
+#endif

src/esp32/hardware/cores/esp32/esp32-hal-adc.h

@@ -0,0 +1,104 @@
+/*
+ Arduino.h - Main include file for the Arduino SDK
+ Copyright (c) 2005-2013 Arduino Team.  All right reserved.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#ifndef MAIN_ESP32_HAL_ADC_H_
+#define MAIN_ESP32_HAL_ADC_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "esp32-hal.h"
+
+typedef enum {
+    ADC_0db,
+    ADC_2_5db,
+    ADC_6db,
+    ADC_11db,
+    ADC_ATTENDB_MAX
+} adc_attenuation_t;
+
+/*
+ * Get ADC value for pin
+ * */
+uint16_t analogRead(uint8_t pin);
+
+/*
+ * Get MilliVolts value for pin
+ * */
+uint32_t analogReadMilliVolts(uint8_t pin);
+
+/*
+ * Set the resolution of analogRead return values. Default is 12 bits (range from 0 to 4096).
+ * If between 9 and 12, it will equal the set hardware resolution, else value will be shifted.
+ * Range is 1 - 16
+ *
+ * Note: compatibility with Arduino SAM
+ */
+void analogReadResolution(uint8_t bits);
+
+/*
+ * Set the divider for the ADC clock.
+ * Default is 1
+ * Range is 1 - 255
+ * */
+void analogSetClockDiv(uint8_t clockDiv);
+
+/*
+ * Set the attenuation for all channels
+ * Default is 11db
+ * */
+void analogSetAttenuation(adc_attenuation_t attenuation);
+
+/*
+ * Set the attenuation for particular pin
+ * Default is 11db
+ * */
+void analogSetPinAttenuation(uint8_t pin, adc_attenuation_t attenuation);
+
+/*
+ * Attach pin to ADC (will also clear any other analog mode that could be on)
+ * */
+bool adcAttachPin(uint8_t pin);
+
+#if CONFIG_IDF_TARGET_ESP32
+/*
+ * Sets the sample bits and read resolution
+ * Default is 12bit (0 - 4095)
+ * Range is 9 - 12
+ * */
+void analogSetWidth(uint8_t bits);
+
+/*
+ * Set pin to use for ADC calibration if the esp is not already calibrated (25, 26 or 27)
+ * */
+void analogSetVRefPin(uint8_t pin);
+
+/*
+ * Get value for HALL sensor (without LNA)
+ * connected to pins 36(SVP) and 39(SVN)
+ * */
+int hallRead();
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* MAIN_ESP32_HAL_ADC_H_ */

src/esp32/hardware/cores/esp32/esp32-hal-bt.c

@@ -0,0 +1,105 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "esp32-hal-bt.h"
+
+#ifdef CONFIG_BT_ENABLED
+
+#if CONFIG_IDF_TARGET_ESP32
+bool btInUse(){ return true; }
+#else
+// user may want to change it to free resources
+__attribute__((weak)) bool btInUse(){ return true; }
+#endif
+
+#include "esp_bt.h"
+
+#ifdef CONFIG_BTDM_CONTROLLER_MODE_BTDM
+#define BT_MODE ESP_BT_MODE_BTDM
+#elif defined(CONFIG_BTDM_CONTROLLER_MODE_BR_EDR_ONLY)
+#define BT_MODE ESP_BT_MODE_CLASSIC_BT
+#else
+#define BT_MODE ESP_BT_MODE_BLE
+#endif
+
+bool btStarted(){
+    return (esp_bt_controller_get_status() == ESP_BT_CONTROLLER_STATUS_ENABLED);
+}
+
+bool btStart(){
+    esp_bt_controller_config_t cfg = BT_CONTROLLER_INIT_CONFIG_DEFAULT();
+    if(esp_bt_controller_get_status() == ESP_BT_CONTROLLER_STATUS_ENABLED){
+        return true;
+    }
+    if(esp_bt_controller_get_status() == ESP_BT_CONTROLLER_STATUS_IDLE){
+        esp_bt_controller_init(&cfg);
+        while(esp_bt_controller_get_status() == ESP_BT_CONTROLLER_STATUS_IDLE){}
+    }
+    if(esp_bt_controller_get_status() == ESP_BT_CONTROLLER_STATUS_INITED){
+        if (esp_bt_controller_enable(BT_MODE)) {
+            log_e("BT Enable failed");
+            return false;
+        }
+    }
+    if(esp_bt_controller_get_status() == ESP_BT_CONTROLLER_STATUS_ENABLED){
+        return true;
+    }
+    log_e("BT Start failed");
+    return false;
+}
+
+bool btStop(){
+    if(esp_bt_controller_get_status() == ESP_BT_CONTROLLER_STATUS_IDLE){
+        return true;
+    }
+    if(esp_bt_controller_get_status() == ESP_BT_CONTROLLER_STATUS_ENABLED){
+        if (esp_bt_controller_disable()) {
+            log_e("BT Disable failed");
+            return false;
+        }
+        while(esp_bt_controller_get_status() == ESP_BT_CONTROLLER_STATUS_ENABLED);
+    }
+    if(esp_bt_controller_get_status() == ESP_BT_CONTROLLER_STATUS_INITED){
+        if (esp_bt_controller_deinit()) {
+			log_e("BT deint failed");
+			return false;
+		}
+		vTaskDelay(1);
+		if (esp_bt_controller_get_status() != ESP_BT_CONTROLLER_STATUS_IDLE) {			
+			return false;		
+		}
+        return true;
+    }
+    log_e("BT Stop failed");
+    return false;
+}
+
+#else // CONFIG_BT_ENABLED
+bool btStarted()
+{
+    return false;
+}
+
+bool btStart()
+{
+    return false;
+}
+
+bool btStop()
+{
+    return false;
+}
+
+#endif // CONFIG_BT_ENABLED
+

src/esp32/hardware/cores/esp32/esp32-hal-bt.h

@@ -0,0 +1,32 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP32_ESP32_HAL_BT_H_
+#define _ESP32_ESP32_HAL_BT_H_
+
+#include "esp32-hal.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+bool btStarted();
+bool btStart();
+bool btStop();
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _ESP32_ESP32_HAL_BT_H_ */

src/esp32/hardware/cores/esp32/esp32-hal-cpu.c

@@ -0,0 +1,262 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "sdkconfig.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/semphr.h"
+#include "freertos/task.h"
+#include "esp_attr.h"
+#include "esp_log.h"
+#include "soc/rtc.h"
+#include "soc/rtc_cntl_reg.h"
+#include "soc/apb_ctrl_reg.h"
+#include "soc/efuse_reg.h"
+#include "esp32-hal.h"
+#include "esp32-hal-cpu.h"
+
+#include "esp_system.h"
+#ifdef ESP_IDF_VERSION_MAJOR // IDF 4+
+#if CONFIG_IDF_TARGET_ESP32 // ESP32/PICO-D4
+#include "freertos/xtensa_timer.h"
+#include "esp32/rom/rtc.h"
+#elif CONFIG_IDF_TARGET_ESP32S2
+#include "freertos/xtensa_timer.h"
+#include "esp32s2/rom/rtc.h"
+#elif CONFIG_IDF_TARGET_ESP32S3
+#include "freertos/xtensa_timer.h"
+#include "esp32s3/rom/rtc.h"
+#elif CONFIG_IDF_TARGET_ESP32C3
+#include "esp32c3/rom/rtc.h"
+#else 
+#error Target CONFIG_IDF_TARGET is not supported
+#endif
+#else // ESP32 Before IDF 4.0
+#include "rom/rtc.h"
+#endif
+
+typedef struct apb_change_cb_s {
+        struct apb_change_cb_s * prev;
+        struct apb_change_cb_s * next;
+        void * arg;
+        apb_change_cb_t cb;
+} apb_change_t;
+
+
+static apb_change_t * apb_change_callbacks = NULL;
+static xSemaphoreHandle apb_change_lock = NULL;
+
+static void initApbChangeCallback(){
+    static volatile bool initialized = false;
+    if(!initialized){
+        initialized = true;
+        apb_change_lock = xSemaphoreCreateMutex();
+        if(!apb_change_lock){
+            initialized = false;
+        }
+    }
+}
+
+static void triggerApbChangeCallback(apb_change_ev_t ev_type, uint32_t old_apb, uint32_t new_apb){
+    initApbChangeCallback();
+    xSemaphoreTake(apb_change_lock, portMAX_DELAY);
+    apb_change_t * r = apb_change_callbacks;
+    if( r != NULL ){
+        if(ev_type == APB_BEFORE_CHANGE )
+            while(r != NULL){
+                r->cb(r->arg, ev_type, old_apb, new_apb);
+                r=r->next;
+            }
+        else { // run backwards through chain
+            while(r->next != NULL) r = r->next; // find first added
+            while( r != NULL){
+                r->cb(r->arg, ev_type, old_apb, new_apb);
+                r=r->prev;
+            }
+        }
+    }
+    xSemaphoreGive(apb_change_lock);
+}
+
+bool addApbChangeCallback(void * arg, apb_change_cb_t cb){
+    initApbChangeCallback();
+    apb_change_t * c = (apb_change_t*)malloc(sizeof(apb_change_t));
+    if(!c){
+        log_e("Callback Object Malloc Failed");
+        return false;
+    }
+    c->next = NULL;
+    c->prev = NULL;
+    c->arg = arg;
+    c->cb = cb;
+    xSemaphoreTake(apb_change_lock, portMAX_DELAY);
+    if(apb_change_callbacks == NULL){
+        apb_change_callbacks = c;
+    } else {
+        apb_change_t * r = apb_change_callbacks;
+        // look for duplicate callbacks
+        while( (r != NULL ) && !((r->cb == cb) && ( r->arg == arg))) r = r->next;
+        if (r) {
+            log_e("duplicate func=%8p arg=%8p",c->cb,c->arg);
+            free(c);
+            xSemaphoreGive(apb_change_lock);
+            return false;
+        }
+        else {
+            c->next = apb_change_callbacks;
+            apb_change_callbacks-> prev = c;
+            apb_change_callbacks = c;
+        }
+    }
+    xSemaphoreGive(apb_change_lock);
+    return true;
+}
+
+bool removeApbChangeCallback(void * arg, apb_change_cb_t cb){
+    initApbChangeCallback();
+    xSemaphoreTake(apb_change_lock, portMAX_DELAY);
+    apb_change_t * r = apb_change_callbacks;
+    // look for matching callback
+    while( (r != NULL ) && !((r->cb == cb) && ( r->arg == arg))) r = r->next;
+    if ( r == NULL ) {
+        log_e("not found func=%8p arg=%8p",cb,arg);
+        xSemaphoreGive(apb_change_lock);
+        return false;
+        }
+    else {
+        // patch links
+        if(r->prev) r->prev->next = r->next;
+        else { // this is first link
+           apb_change_callbacks = r->next;
+        }
+        if(r->next) r->next->prev = r->prev;
+        free(r);
+    }
+    xSemaphoreGive(apb_change_lock);
+    return true;
+}
+
+static uint32_t calculateApb(rtc_cpu_freq_config_t * conf){
+#if CONFIG_IDF_TARGET_ESP32C3 || CONFIG_IDF_TARGET_ESP32S3
+	return APB_CLK_FREQ;
+#else
+    if(conf->freq_mhz >= 80){
+        return 80 * MHZ;
+    }
+    return (conf->source_freq_mhz * MHZ) / conf->div;
+#endif
+}
+
+void esp_timer_impl_update_apb_freq(uint32_t apb_ticks_per_us); //private in IDF
+
+bool setCpuFrequencyMhz(uint32_t cpu_freq_mhz){
+    rtc_cpu_freq_config_t conf, cconf;
+    uint32_t capb, apb;
+    //Get XTAL Frequency and calculate min CPU MHz
+    rtc_xtal_freq_t xtal = rtc_clk_xtal_freq_get();
+#if CONFIG_IDF_TARGET_ESP32
+    if(xtal > RTC_XTAL_FREQ_AUTO){
+        if(xtal < RTC_XTAL_FREQ_40M) {
+            if(cpu_freq_mhz <= xtal && cpu_freq_mhz != xtal && cpu_freq_mhz != (xtal/2)){
+                log_e("Bad frequency: %u MHz! Options are: 240, 160, 80, %u and %u MHz", cpu_freq_mhz, xtal, xtal/2);
+                return false;
+            }
+        } else if(cpu_freq_mhz <= xtal && cpu_freq_mhz != xtal && cpu_freq_mhz != (xtal/2) && cpu_freq_mhz != (xtal/4)){
+            log_e("Bad frequency: %u MHz! Options are: 240, 160, 80, %u, %u and %u MHz", cpu_freq_mhz, xtal, xtal/2, xtal/4);
+            return false;
+        }
+    }
+#endif
+    if(cpu_freq_mhz > xtal && cpu_freq_mhz != 240 && cpu_freq_mhz != 160 && cpu_freq_mhz != 80){
+        if(xtal >= RTC_XTAL_FREQ_40M){
+            log_e("Bad frequency: %u MHz! Options are: 240, 160, 80, %u, %u and %u MHz", cpu_freq_mhz, xtal, xtal/2, xtal/4);
+        } else {
+            log_e("Bad frequency: %u MHz! Options are: 240, 160, 80, %u and %u MHz", cpu_freq_mhz, xtal, xtal/2);
+        }
+        return false;
+    }
+#if CONFIG_IDF_TARGET_ESP32
+    //check if cpu supports the frequency
+    if(cpu_freq_mhz == 240){
+        //Check if ESP32 is rated for a CPU frequency of 160MHz only
+        if (REG_GET_BIT(EFUSE_BLK0_RDATA3_REG, EFUSE_RD_CHIP_CPU_FREQ_RATED) &&
+            REG_GET_BIT(EFUSE_BLK0_RDATA3_REG, EFUSE_RD_CHIP_CPU_FREQ_LOW)) {
+            log_e("Can not switch to 240 MHz! Chip CPU frequency rated for 160MHz.");
+            cpu_freq_mhz = 160;
+        }
+    }
+#endif
+    //Get current CPU clock configuration
+    rtc_clk_cpu_freq_get_config(&cconf);
+    //return if frequency has not changed
+    if(cconf.freq_mhz == cpu_freq_mhz){
+        return true;
+    }
+    //Get configuration for the new CPU frequency
+    if(!rtc_clk_cpu_freq_mhz_to_config(cpu_freq_mhz, &conf)){
+        log_e("CPU clock could not be set to %u MHz", cpu_freq_mhz);
+        return false;
+    }
+    //Current APB
+    capb = calculateApb(&cconf);
+    //New APB
+    apb = calculateApb(&conf);
+    
+    //Call peripheral functions before the APB change
+    if(apb_change_callbacks){
+        triggerApbChangeCallback(APB_BEFORE_CHANGE, capb, apb);
+    }
+    //Make the frequency change
+    rtc_clk_cpu_freq_set_config_fast(&conf);
+    if(capb != apb){
+        //Update REF_TICK (uncomment if REF_TICK is different than 1MHz)
+        //if(conf.freq_mhz < 80){
+        //    ESP_REG(APB_CTRL_XTAL_TICK_CONF_REG) = conf.freq_mhz / (REF_CLK_FREQ / MHZ) - 1;
+        // }
+        //Update APB Freq REG
+        rtc_clk_apb_freq_update(apb);
+        //Update esp_timer divisor
+        esp_timer_impl_update_apb_freq(apb / MHZ);
+    }
+    //Update FreeRTOS Tick Divisor
+#if CONFIG_IDF_TARGET_ESP32C3
+
+#elif CONFIG_IDF_TARGET_ESP32S3
+
+#else
+    uint32_t fcpu = (conf.freq_mhz >= 80)?(conf.freq_mhz * MHZ):(apb);
+    _xt_tick_divisor = fcpu / XT_TICK_PER_SEC;
+#endif
+    //Call peripheral functions after the APB change
+    if(apb_change_callbacks){
+        triggerApbChangeCallback(APB_AFTER_CHANGE, capb, apb);
+    }
+    log_d("%s: %u / %u = %u Mhz, APB: %u Hz", (conf.source == RTC_CPU_FREQ_SRC_PLL)?"PLL":((conf.source == RTC_CPU_FREQ_SRC_APLL)?"APLL":((conf.source == RTC_CPU_FREQ_SRC_XTAL)?"XTAL":"8M")), conf.source_freq_mhz, conf.div, conf.freq_mhz, apb);
+    return true;
+}
+
+uint32_t getCpuFrequencyMhz(){
+    rtc_cpu_freq_config_t conf;
+    rtc_clk_cpu_freq_get_config(&conf);
+    return conf.freq_mhz;
+}
+
+uint32_t getXtalFrequencyMhz(){
+    return rtc_clk_xtal_freq_get();
+}
+
+uint32_t getApbFrequency(){
+    rtc_cpu_freq_config_t conf;
+    rtc_clk_cpu_freq_get_config(&conf);
+    return calculateApb(&conf);
+}

src/esp32/hardware/cores/esp32/esp32-hal-cpu.h

@@ -0,0 +1,48 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP32_HAL_CPU_H_
+#define _ESP32_HAL_CPU_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdlib.h>
+
+typedef enum { APB_BEFORE_CHANGE, APB_AFTER_CHANGE } apb_change_ev_t;
+
+typedef void (* apb_change_cb_t)(void * arg, apb_change_ev_t ev_type, uint32_t old_apb, uint32_t new_apb);
+
+bool addApbChangeCallback(void * arg, apb_change_cb_t cb);
+bool removeApbChangeCallback(void * arg, apb_change_cb_t cb);
+
+//function takes the following frequencies as valid values:
+//  240, 160, 80    <<< For all XTAL types
+//  40, 20, 10      <<< For 40MHz XTAL
+//  26, 13          <<< For 26MHz XTAL
+//  24, 12          <<< For 24MHz XTAL
+bool setCpuFrequencyMhz(uint32_t cpu_freq_mhz);
+
+uint32_t getCpuFrequencyMhz();  // In MHz
+uint32_t getXtalFrequencyMhz(); // In MHz
+uint32_t getApbFrequency();     // In Hz
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _ESP32_HAL_CPU_H_ */

src/esp32/hardware/cores/esp32/esp32-hal-dac.c

@@ -0,0 +1,49 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "esp32-hal.h"
+#include "soc/soc_caps.h"
+
+#ifndef SOC_DAC_SUPPORTED           
+#define NODAC
+#else
+#include "soc/dac_channel.h"
+#include "driver/dac_common.h"
+
+void ARDUINO_ISR_ATTR __dacWrite(uint8_t pin, uint8_t value)
+{
+    if(pin < DAC_CHANNEL_1_GPIO_NUM || pin > DAC_CHANNEL_2_GPIO_NUM){
+        return;//not dac pin
+    }
+
+    uint8_t channel = pin - DAC_CHANNEL_1_GPIO_NUM;
+    dac_output_enable(channel);
+    dac_output_voltage(channel, value);
+
+}
+
+void ARDUINO_ISR_ATTR __dacDisable(uint8_t pin)
+{
+    if(pin < DAC_CHANNEL_1_GPIO_NUM || pin > DAC_CHANNEL_2_GPIO_NUM){
+        return;//not dac pin
+    }
+
+    uint8_t channel = pin - DAC_CHANNEL_1_GPIO_NUM;
+    dac_output_disable(channel);
+}
+
+extern void dacWrite(uint8_t pin, uint8_t value) __attribute__ ((weak, alias("__dacWrite")));
+extern void dacDisable(uint8_t pin) __attribute__ ((weak, alias("__dacDisable")));
+
+#endif

src/esp32/hardware/cores/esp32/esp32-hal-dac.h

@@ -0,0 +1,37 @@
+/*
+ Arduino.h - Main include file for the Arduino SDK
+ Copyright (c) 2005-2013 Arduino Team.  All right reserved.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#ifndef MAIN_ESP32_HAL_DAC_H_
+#define MAIN_ESP32_HAL_DAC_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "esp32-hal.h"
+#include "driver/gpio.h"
+
+void dacWrite(uint8_t pin, uint8_t value);
+void dacDisable(uint8_t pin);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* MAIN_ESP32_HAL_DAC_H_ */

src/esp32/hardware/cores/esp32/esp32-hal-gpio.c

@@ -0,0 +1,236 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "esp32-hal-gpio.h"
+#include "hal/gpio_hal.h"
+#include "soc/soc_caps.h"
+
+// It fixes lack of pin definition for S3 and for any future SoC
+// this function works for ESP32, ESP32-S2 and ESP32-S3 - including the C3, it will return -1 for any pin
+#if SOC_TOUCH_SENSOR_NUM >  0
+#include "soc/touch_sensor_periph.h"
+
+int8_t digitalPinToTouchChannel(uint8_t pin) 
+{
+    int8_t ret = -1;
+    if (pin < SOC_GPIO_PIN_COUNT) {
+        for (uint8_t i = 0; i < SOC_TOUCH_SENSOR_NUM; i++) {
+            if (touch_sensor_channel_io_map[i] == pin) {
+                ret = i;
+                break;
+            }
+        }
+    }
+    return ret;
+}
+#else
+// No Touch Sensor available
+int8_t digitalPinToTouchChannel(uint8_t pin) 
+{
+    return -1;
+}
+#endif
+
+#ifdef SOC_ADC_SUPPORTED
+#include "soc/adc_periph.h"
+
+int8_t digitalPinToAnalogChannel(uint8_t pin) 
+{
+    uint8_t channel = 0;
+    if (pin < SOC_GPIO_PIN_COUNT) {
+        for (uint8_t i = 0; i < SOC_ADC_PERIPH_NUM; i++) {
+            for (uint8_t j = 0; j < SOC_ADC_MAX_CHANNEL_NUM; j++) {
+                if (adc_channel_io_map[i][j] == pin) {
+                    return channel;
+                }
+                channel++;
+            }
+        }
+    }
+    return -1;
+}
+
+int8_t analogChannelToDigitalPin(uint8_t channel) 
+{
+    if (channel >= (SOC_ADC_PERIPH_NUM * SOC_ADC_MAX_CHANNEL_NUM)) {
+        return -1;
+    }
+    uint8_t adc_unit = (channel / SOC_ADC_MAX_CHANNEL_NUM);
+    uint8_t adc_chan = (channel % SOC_ADC_MAX_CHANNEL_NUM);
+    return adc_channel_io_map[adc_unit][adc_chan];
+}
+#else
+// No Analog channels availible
+int8_t analogChannelToDigitalPin(uint8_t channel) 
+{
+    return -1;
+}
+#endif
+
+typedef void (*voidFuncPtr)(void);
+typedef void (*voidFuncPtrArg)(void*);
+typedef struct {
+    voidFuncPtr fn;
+    void* arg;
+    bool functional;
+} InterruptHandle_t;
+static InterruptHandle_t __pinInterruptHandlers[SOC_GPIO_PIN_COUNT] = {0,};
+
+#include "driver/rtc_io.h"
+
+extern void ARDUINO_ISR_ATTR __pinMode(uint8_t pin, uint8_t mode)
+{
+#ifdef RGB_BUILTIN
+    if (pin == RGB_BUILTIN){
+        __pinMode(RGB_BUILTIN-SOC_GPIO_PIN_COUNT, mode);
+        return;
+    }
+#endif
+
+    if (!GPIO_IS_VALID_GPIO(pin)) {
+        log_e("Invalid pin selected");
+        return;
+    }
+    
+    gpio_hal_context_t gpiohal;
+    gpiohal.dev = GPIO_LL_GET_HW(GPIO_PORT_0);
+
+    gpio_config_t conf = {
+        .pin_bit_mask = (1ULL<<pin),                 /*!< GPIO pin: set with bit mask, each bit maps to a GPIO */
+        .mode = GPIO_MODE_DISABLE,                   /*!< GPIO mode: set input/output mode                     */
+        .pull_up_en = GPIO_PULLUP_DISABLE,           /*!< GPIO pull-up                                         */
+        .pull_down_en = GPIO_PULLDOWN_DISABLE,       /*!< GPIO pull-down                                       */
+        .intr_type = gpiohal.dev->pin[pin].int_type  /*!< GPIO interrupt type - previously set                 */
+    };
+    if (mode < 0x20) {//io
+        conf.mode = mode & (INPUT | OUTPUT);
+        if (mode & OPEN_DRAIN) {
+            conf.mode |= GPIO_MODE_DEF_OD;
+        }
+        if (mode & PULLUP) {
+            conf.pull_up_en = GPIO_PULLUP_ENABLE;
+        }
+        if (mode & PULLDOWN) {
+            conf.pull_down_en = GPIO_PULLDOWN_ENABLE;
+        }
+    }
+    if(gpio_config(&conf) != ESP_OK)
+    {
+        log_e("GPIO config failed");
+        return;
+    }
+}
+
+extern void ARDUINO_ISR_ATTR __digitalWrite(uint8_t pin, uint8_t val)
+{
+    #ifdef RGB_BUILTIN
+        if(pin == RGB_BUILTIN){
+            //use RMT to set all channels on/off
+            const uint8_t comm_val = val != 0 ? RGB_BRIGHTNESS : 0;
+            neopixelWrite(RGB_BUILTIN, comm_val, comm_val, comm_val);
+            return;
+        }
+    #endif
+	gpio_set_level((gpio_num_t)pin, val);
+}
+
+extern int ARDUINO_ISR_ATTR __digitalRead(uint8_t pin)
+{
+	return gpio_get_level((gpio_num_t)pin);
+}
+
+static void ARDUINO_ISR_ATTR __onPinInterrupt(void * arg) {
+	InterruptHandle_t * isr = (InterruptHandle_t*)arg;
+    if(isr->fn) {
+        if(isr->arg){
+            ((voidFuncPtrArg)isr->fn)(isr->arg);
+        } else {
+        	isr->fn();
+        }
+    }
+}
+
+extern void cleanupFunctional(void* arg);
+
+extern void __attachInterruptFunctionalArg(uint8_t pin, voidFuncPtrArg userFunc, void * arg, int intr_type, bool functional)
+{
+    static bool interrupt_initialized = false;
+
+    // makes sure that pin -1 (255) will never work -- this follows Arduino standard
+    if (pin >= SOC_GPIO_PIN_COUNT) return;
+
+    if(!interrupt_initialized) {
+    	esp_err_t err = gpio_install_isr_service((int)ARDUINO_ISR_FLAG);
+    	interrupt_initialized = (err == ESP_OK) || (err == ESP_ERR_INVALID_STATE);
+    }
+    if(!interrupt_initialized) {
+    	log_e("GPIO ISR Service Failed To Start");
+    	return;
+    }
+
+    // if new attach without detach remove old info
+    if (__pinInterruptHandlers[pin].functional && __pinInterruptHandlers[pin].arg)
+    {
+    	cleanupFunctional(__pinInterruptHandlers[pin].arg);
+    }
+    __pinInterruptHandlers[pin].fn = (voidFuncPtr)userFunc;
+    __pinInterruptHandlers[pin].arg = arg;
+    __pinInterruptHandlers[pin].functional = functional;
+
+    gpio_set_intr_type((gpio_num_t)pin, (gpio_int_type_t)(intr_type & 0x7));
+    if(intr_type & 0x8){
+    	gpio_wakeup_enable((gpio_num_t)pin, (gpio_int_type_t)(intr_type & 0x7));
+    }
+    gpio_isr_handler_add((gpio_num_t)pin, __onPinInterrupt, &__pinInterruptHandlers[pin]);
+
+
+    //FIX interrupts on peripherals outputs (eg. LEDC,...)
+    //Enable input in GPIO register
+    gpio_hal_context_t gpiohal;
+    gpiohal.dev = GPIO_LL_GET_HW(GPIO_PORT_0);
+    gpio_hal_input_enable(&gpiohal, pin);
+}
+
+extern void __attachInterruptArg(uint8_t pin, voidFuncPtrArg userFunc, void * arg, int intr_type)
+{
+	__attachInterruptFunctionalArg(pin, userFunc, arg, intr_type, false);
+}
+
+extern void __attachInterrupt(uint8_t pin, voidFuncPtr userFunc, int intr_type) {
+    __attachInterruptFunctionalArg(pin, (voidFuncPtrArg)userFunc, NULL, intr_type, false);
+}
+
+extern void __detachInterrupt(uint8_t pin)
+{
+	gpio_isr_handler_remove((gpio_num_t)pin); //remove handle and disable isr for pin
+	gpio_wakeup_disable((gpio_num_t)pin);
+
+    if (__pinInterruptHandlers[pin].functional && __pinInterruptHandlers[pin].arg)
+    {
+    	cleanupFunctional(__pinInterruptHandlers[pin].arg);
+    }
+    __pinInterruptHandlers[pin].fn = NULL;
+    __pinInterruptHandlers[pin].arg = NULL;
+    __pinInterruptHandlers[pin].functional = false;
+
+    gpio_set_intr_type((gpio_num_t)pin, GPIO_INTR_DISABLE);
+}
+
+
+extern void pinMode(uint8_t pin, uint8_t mode) __attribute__ ((weak, alias("__pinMode")));
+extern void digitalWrite(uint8_t pin, uint8_t val) __attribute__ ((weak, alias("__digitalWrite")));
+extern int digitalRead(uint8_t pin) __attribute__ ((weak, alias("__digitalRead")));
+extern void attachInterrupt(uint8_t pin, voidFuncPtr handler, int mode) __attribute__ ((weak, alias("__attachInterrupt")));
+extern void attachInterruptArg(uint8_t pin, voidFuncPtrArg handler, void * arg, int mode) __attribute__ ((weak, alias("__attachInterruptArg")));
+extern void detachInterrupt(uint8_t pin) __attribute__ ((weak, alias("__detachInterrupt")));

src/esp32/hardware/cores/esp32/esp32-hal-gpio.h

@@ -0,0 +1,90 @@
+/*
+ Arduino.h - Main include file for the Arduino SDK
+ Copyright (c) 2005-2013 Arduino Team.  All right reserved.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#ifndef MAIN_ESP32_HAL_GPIO_H_
+#define MAIN_ESP32_HAL_GPIO_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "esp32-hal.h"
+#include "soc/soc_caps.h"
+#include "pins_arduino.h"
+
+#if (CONFIG_IDF_TARGET_ESP32S2 || CONFIG_IDF_TARGET_ESP32S3)
+#define NUM_OUPUT_PINS  46
+#define PIN_DAC1        17
+#define PIN_DAC2        18
+#else
+#define NUM_OUPUT_PINS  34
+#define PIN_DAC1        25
+#define PIN_DAC2        26
+#endif
+
+#define LOW               0x0
+#define HIGH              0x1
+
+//GPIO FUNCTIONS
+#define INPUT             0x01
+// Changed OUTPUT from 0x02 to behave the same as Arduino pinMode(pin,OUTPUT) 
+// where you can read the state of pin even when it is set as OUTPUT
+#define OUTPUT            0x03 
+#define PULLUP            0x04
+#define INPUT_PULLUP      0x05
+#define PULLDOWN          0x08
+#define INPUT_PULLDOWN    0x09
+#define OPEN_DRAIN        0x10
+#define OUTPUT_OPEN_DRAIN 0x13
+#define ANALOG            0xC0
+
+//Interrupt Modes
+#define DISABLED  0x00
+#define RISING    0x01
+#define FALLING   0x02
+#define CHANGE    0x03
+#define ONLOW     0x04
+#define ONHIGH    0x05
+#define ONLOW_WE  0x0C
+#define ONHIGH_WE 0x0D
+
+
+#define digitalPinIsValid(pin)          GPIO_IS_VALID_GPIO(pin)
+#define digitalPinCanOutput(pin)        GPIO_IS_VALID_OUTPUT_GPIO(pin)
+
+#define digitalPinToRtcPin(pin)         ((RTC_GPIO_IS_VALID_GPIO(pin))?rtc_io_number_get(pin):-1) 
+#define digitalPinToDacChannel(pin)     (((pin) == DAC_CHANNEL_1_GPIO_NUM)?0:((pin) == DAC_CHANNEL_2_GPIO_NUM)?1:-1)
+
+void pinMode(uint8_t pin, uint8_t mode);
+void digitalWrite(uint8_t pin, uint8_t val);
+int digitalRead(uint8_t pin);
+
+void attachInterrupt(uint8_t pin, void (*)(void), int mode);
+void attachInterruptArg(uint8_t pin, void (*)(void*), void * arg, int mode);
+void detachInterrupt(uint8_t pin);
+
+int8_t digitalPinToTouchChannel(uint8_t pin);
+int8_t digitalPinToAnalogChannel(uint8_t pin);
+int8_t analogChannelToDigitalPin(uint8_t channel);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* MAIN_ESP32_HAL_GPIO_H_ */

src/esp32/hardware/cores/esp32/esp32-hal-i2c-slave.c

@@ -0,0 +1,841 @@
+// Copyright 2015-2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <inttypes.h>
+#include <string.h>
+#include <math.h>
+
+#include "sdkconfig.h"
+#include "esp_attr.h"
+#include "rom/gpio.h"
+#include "soc/gpio_sig_map.h"
+#include "hal/gpio_types.h"
+#include "driver/gpio.h"
+#include "esp_err.h"
+
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "freertos/queue.h"
+#include "freertos/semphr.h"
+#include "freertos/ringbuf.h"
+
+#include "esp_intr_alloc.h"
+#include "driver/periph_ctrl.h"
+#include "soc/i2c_reg.h"
+#include "soc/i2c_struct.h"
+#include "hal/i2c_ll.h"
+#include "esp32-hal-log.h"
+#include "esp32-hal-i2c-slave.h"
+
+#define I2C_SLAVE_USE_RX_QUEUE 0 // 1: Queue, 0: RingBuffer
+
+#if SOC_I2C_NUM > 1
+#define I2C_SCL_IDX(p)  ((p==0)?I2CEXT0_SCL_OUT_IDX:((p==1)?I2CEXT1_SCL_OUT_IDX:0))
+#define I2C_SDA_IDX(p) ((p==0)?I2CEXT0_SDA_OUT_IDX:((p==1)?I2CEXT1_SDA_OUT_IDX:0))
+#else
+#define I2C_SCL_IDX(p)  I2CEXT0_SCL_OUT_IDX
+#define I2C_SDA_IDX(p) I2CEXT0_SDA_OUT_IDX
+#endif
+
+#if CONFIG_IDF_TARGET_ESP32
+    #define I2C_TXFIFO_WM_INT_ENA    I2C_TXFIFO_EMPTY_INT_ENA
+    #define I2C_RXFIFO_WM_INT_ENA     I2C_RXFIFO_FULL_INT_ENA
+#endif
+
+enum {
+    I2C_SLAVE_EVT_RX, I2C_SLAVE_EVT_TX
+};
+
+typedef struct i2c_slave_struct_t {
+    i2c_dev_t * dev;
+    uint8_t num;
+    int8_t sda;
+    int8_t scl;
+    i2c_slave_request_cb_t request_callback;
+    i2c_slave_receive_cb_t receive_callback;
+    void * arg;
+    intr_handle_t intr_handle;
+    TaskHandle_t task_handle;
+    xQueueHandle event_queue;
+#if I2C_SLAVE_USE_RX_QUEUE
+    xQueueHandle rx_queue;
+#else
+    RingbufHandle_t rx_ring_buf;
+#endif
+    xQueueHandle tx_queue;
+    uint32_t rx_data_count;
+#if !CONFIG_DISABLE_HAL_LOCKS
+    xSemaphoreHandle lock;
+#endif
+} i2c_slave_struct_t;
+
+typedef union {
+    struct {
+        uint32_t event : 2;
+        uint32_t stop : 1;
+        uint32_t param : 29;
+    };
+    uint32_t val;
+} i2c_slave_queue_event_t;
+
+static i2c_slave_struct_t _i2c_bus_array[SOC_I2C_NUM] = {
+    { &I2C0, 0, -1, -1, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, 0
+#if !CONFIG_DISABLE_HAL_LOCKS
+    , NULL
+#endif
+    },
+#if SOC_I2C_NUM > 1
+    { &I2C1, 1, -1, -1, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, 0
+#if !CONFIG_DISABLE_HAL_LOCKS
+    , NULL
+#endif
+    }
+#endif
+};
+
+#if CONFIG_DISABLE_HAL_LOCKS
+#define I2C_SLAVE_MUTEX_LOCK()
+#define I2C_SLAVE_MUTEX_UNLOCK()
+#else
+#define I2C_SLAVE_MUTEX_LOCK()    if(i2c->lock){xSemaphoreTake(i2c->lock, portMAX_DELAY);}
+#define I2C_SLAVE_MUTEX_UNLOCK()  if(i2c->lock){xSemaphoreGive(i2c->lock);}
+#endif
+
+//-------------------------------------- HAL_LL (Missing Functions) ------------------------------------------------
+typedef enum {
+    I2C_STRETCH_CAUSE_MASTER_READ,
+    I2C_STRETCH_CAUSE_TX_FIFO_EMPTY,
+    I2C_STRETCH_CAUSE_RX_FIFO_FULL,
+    I2C_STRETCH_CAUSE_MAX
+} i2c_stretch_cause_t;
+
+static inline i2c_stretch_cause_t i2c_ll_stretch_cause(i2c_dev_t *hw)
+{
+#if CONFIG_IDF_TARGET_ESP32C3 || CONFIG_IDF_TARGET_ESP32S3
+    return hw->sr.stretch_cause;
+#elif CONFIG_IDF_TARGET_ESP32S2
+    return hw->status_reg.stretch_cause;
+#else
+    return I2C_STRETCH_CAUSE_MAX;
+#endif
+}
+
+static inline void i2c_ll_set_stretch(i2c_dev_t *hw, uint16_t time)
+{
+#ifndef CONFIG_IDF_TARGET_ESP32
+    typeof(hw->scl_stretch_conf) scl_stretch_conf;
+    scl_stretch_conf.val = 0;
+    scl_stretch_conf.slave_scl_stretch_en = (time > 0);
+    scl_stretch_conf.stretch_protect_num = time;
+    scl_stretch_conf.slave_scl_stretch_clr = 1;
+    hw->scl_stretch_conf.val = scl_stretch_conf.val;
+    if(time > 0){
+        //enable interrupt
+        hw->int_ena.val |= I2C_SLAVE_STRETCH_INT_ENA;
+    } else {
+        //disable interrupt
+        hw->int_ena.val &= (~I2C_SLAVE_STRETCH_INT_ENA);
+    }
+#endif
+}
+
+static inline void i2c_ll_stretch_clr(i2c_dev_t *hw)
+{
+#ifndef CONFIG_IDF_TARGET_ESP32
+    hw->scl_stretch_conf.slave_scl_stretch_clr = 1;
+#endif
+}
+
+static inline bool i2c_ll_slave_addressed(i2c_dev_t *hw)
+{
+#if CONFIG_IDF_TARGET_ESP32C3 || CONFIG_IDF_TARGET_ESP32S3
+    return hw->sr.slave_addressed;
+#else
+    return hw->status_reg.slave_addressed;
+#endif
+}
+
+static inline bool i2c_ll_slave_rw(i2c_dev_t *hw)//not exposed by hal_ll
+{
+#if CONFIG_IDF_TARGET_ESP32C3 || CONFIG_IDF_TARGET_ESP32S3
+    return hw->sr.slave_rw;
+#else
+    return hw->status_reg.slave_rw;
+#endif
+}
+
+//-------------------------------------- PRIVATE (Function Prototypes) ------------------------------------------------
+static void i2c_slave_free_resources(i2c_slave_struct_t * i2c);
+static void i2c_slave_delay_us(uint64_t us);
+static void i2c_slave_gpio_mode(int8_t pin, gpio_mode_t mode);
+static bool i2c_slave_check_line_state(int8_t sda, int8_t scl);
+static bool i2c_slave_attach_gpio(i2c_slave_struct_t * i2c, int8_t sda, int8_t scl);
+static bool i2c_slave_detach_gpio(i2c_slave_struct_t * i2c);
+static bool i2c_slave_set_frequency(i2c_slave_struct_t * i2c, uint32_t clk_speed);
+static bool i2c_slave_send_event(i2c_slave_struct_t * i2c, i2c_slave_queue_event_t* event);
+static bool i2c_slave_handle_tx_fifo_empty(i2c_slave_struct_t * i2c);
+static bool i2c_slave_handle_rx_fifo_full(i2c_slave_struct_t * i2c, uint32_t len);
+static size_t i2c_slave_read_rx(i2c_slave_struct_t * i2c, uint8_t * data, size_t len);
+static void i2c_slave_isr_handler(void* arg);
+static void i2c_slave_task(void *pv_args);
+
+
+//=====================================================================================================================
+//-------------------------------------- Public Functions -------------------------------------------------------------
+//=====================================================================================================================
+
+esp_err_t i2cSlaveAttachCallbacks(uint8_t num, i2c_slave_request_cb_t request_callback, i2c_slave_receive_cb_t receive_callback, void * arg){
+    if(num >= SOC_I2C_NUM){
+        log_e("Invalid port num: %u", num);
+        return ESP_ERR_INVALID_ARG;
+    }
+    i2c_slave_struct_t * i2c = &_i2c_bus_array[num];
+    I2C_SLAVE_MUTEX_LOCK();
+    i2c->request_callback = request_callback;
+    i2c->receive_callback = receive_callback;
+    i2c->arg = arg;
+    I2C_SLAVE_MUTEX_UNLOCK();
+    return ESP_OK;
+}
+
+esp_err_t i2cSlaveInit(uint8_t num, int sda, int scl, uint16_t slaveID, uint32_t frequency, size_t rx_len, size_t tx_len) {
+    if(num >= SOC_I2C_NUM){
+        log_e("Invalid port num: %u", num);
+        return ESP_ERR_INVALID_ARG;
+    }
+
+    if (sda < 0 || scl < 0) {
+        log_e("invalid pins sda=%d, scl=%d", sda, scl);
+        return ESP_ERR_INVALID_ARG;
+    }
+
+    if(!frequency){
+        frequency = 100000;
+    } else if(frequency > 1000000){
+        frequency = 1000000;
+    }
+
+    log_i("Initialising I2C Slave: sda=%d scl=%d freq=%d, addr=0x%x", sda, scl, frequency, slaveID);
+
+    i2c_slave_struct_t * i2c = &_i2c_bus_array[num];
+    esp_err_t ret = ESP_OK;
+
+#if !CONFIG_DISABLE_HAL_LOCKS
+    if(!i2c->lock){
+        i2c->lock = xSemaphoreCreateMutex();
+        if (i2c->lock == NULL) {
+            log_e("RX queue create failed");
+            return ESP_ERR_NO_MEM;
+        }
+    }
+#endif
+
+    I2C_SLAVE_MUTEX_LOCK();
+    i2c_slave_free_resources(i2c);
+
+#if I2C_SLAVE_USE_RX_QUEUE
+    i2c->rx_queue = xQueueCreate(rx_len, sizeof(uint8_t));
+    if (i2c->rx_queue == NULL) {
+        log_e("RX queue create failed");
+        ret = ESP_ERR_NO_MEM;
+        goto fail;
+    }
+#else
+    i2c->rx_ring_buf = xRingbufferCreate(rx_len, RINGBUF_TYPE_BYTEBUF);
+    if (i2c->rx_ring_buf == NULL) {
+        log_e("RX RingBuf create failed");
+        ret = ESP_ERR_NO_MEM;
+        goto fail;
+    }
+#endif
+
+    i2c->tx_queue = xQueueCreate(tx_len, sizeof(uint8_t));
+    if (i2c->tx_queue == NULL) {
+        log_e("TX queue create failed");
+        ret = ESP_ERR_NO_MEM;
+        goto fail;
+    }
+
+    i2c->event_queue = xQueueCreate(16, sizeof(i2c_slave_queue_event_t));
+    if (i2c->event_queue == NULL) {
+        log_e("Event queue create failed");
+        ret = ESP_ERR_NO_MEM;
+        goto fail;
+    }
+
+    xTaskCreate(i2c_slave_task, "i2c_slave_task", 4096, i2c, 20, &i2c->task_handle);
+    if(i2c->task_handle == NULL){
+        log_e("Event thread create failed");
+        ret = ESP_ERR_NO_MEM;
+        goto fail;
+    }
+
+    if (frequency == 0) {
+        frequency = 100000L;
+    }
+    frequency = (frequency * 5) / 4;
+
+    if (i2c->num == 0) {
+        periph_module_enable(PERIPH_I2C0_MODULE);
+#if SOC_I2C_NUM > 1
+    } else {
+        periph_module_enable(PERIPH_I2C1_MODULE);
+#endif
+    }
+    
+    i2c_ll_slave_init(i2c->dev);
+    i2c_ll_set_fifo_mode(i2c->dev, true);
+    i2c_ll_set_slave_addr(i2c->dev, slaveID, false);
+    i2c_ll_set_tout(i2c->dev, I2C_LL_MAX_TIMEOUT);
+    i2c_slave_set_frequency(i2c, frequency);
+
+    if (!i2c_slave_check_line_state(sda, scl)) {
+        log_e("bad pin state");
+        ret = ESP_FAIL;
+        goto fail;
+    }
+
+    i2c_slave_attach_gpio(i2c, sda, scl);
+
+    if (i2c_ll_is_bus_busy(i2c->dev)) {
+        log_w("Bus busy, reinit");
+        ret = ESP_FAIL;
+        goto fail;
+    }
+
+    i2c_ll_disable_intr_mask(i2c->dev, I2C_LL_INTR_MASK);
+    i2c_ll_clr_intsts_mask(i2c->dev, I2C_LL_INTR_MASK);
+    i2c_ll_set_fifo_mode(i2c->dev, true);
+
+    if (!i2c->intr_handle) {
+        uint32_t flags = ESP_INTR_FLAG_LOWMED | ESP_INTR_FLAG_SHARED;
+        if(i2c->num == 0) {
+            ret = esp_intr_alloc(ETS_I2C_EXT0_INTR_SOURCE, flags, &i2c_slave_isr_handler, i2c, &i2c->intr_handle);
+#if SOC_I2C_NUM > 1
+        } else {
+            ret = esp_intr_alloc(ETS_I2C_EXT1_INTR_SOURCE, flags, &i2c_slave_isr_handler, i2c, &i2c->intr_handle);
+#endif
+        }
+
+        if (ret != ESP_OK) {
+            log_e("install interrupt handler Failed=%d", ret);
+            goto fail;
+        }
+    }
+    
+    i2c_ll_txfifo_rst(i2c->dev);
+    i2c_ll_rxfifo_rst(i2c->dev);
+    i2c_ll_slave_enable_rx_it(i2c->dev);
+    i2c_ll_set_stretch(i2c->dev, 0x3FF);
+    i2c_ll_update(i2c->dev);
+    I2C_SLAVE_MUTEX_UNLOCK();
+    return ret;
+
+fail:
+    i2c_slave_free_resources(i2c);
+    I2C_SLAVE_MUTEX_UNLOCK();
+    return ret;
+}
+
+esp_err_t i2cSlaveDeinit(uint8_t num){
+    if(num >= SOC_I2C_NUM){
+        log_e("Invalid port num: %u", num);
+        return ESP_ERR_INVALID_ARG;
+    }
+
+    i2c_slave_struct_t * i2c = &_i2c_bus_array[num];
+#if !CONFIG_DISABLE_HAL_LOCKS
+    if(!i2c->lock){
+        log_e("Lock is not initialized! Did you call i2c_slave_init()?");
+        return ESP_ERR_NO_MEM;
+    }
+#endif
+    I2C_SLAVE_MUTEX_LOCK();
+    i2c_slave_free_resources(i2c);
+    I2C_SLAVE_MUTEX_UNLOCK();
+    return ESP_OK;
+}
+
+size_t i2cSlaveWrite(uint8_t num, const uint8_t *buf, uint32_t len, uint32_t timeout_ms) {
+    if(num >= SOC_I2C_NUM){
+        log_e("Invalid port num: %u", num);
+        return 0;
+    }
+    size_t to_queue = 0, to_fifo = 0;
+    i2c_slave_struct_t * i2c = &_i2c_bus_array[num];
+#if !CONFIG_DISABLE_HAL_LOCKS
+    if(!i2c->lock){
+        log_e("Lock is not initialized! Did you call i2c_slave_init()?");
+        return ESP_ERR_NO_MEM;
+    }
+#endif
+    if(!i2c->tx_queue){
+        return 0;
+    }
+    I2C_SLAVE_MUTEX_LOCK();
+#if CONFIG_IDF_TARGET_ESP32
+    i2c_ll_slave_disable_tx_it(i2c->dev);
+    if (i2c_ll_get_txfifo_len(i2c->dev) < SOC_I2C_FIFO_LEN) {
+        i2c_ll_txfifo_rst(i2c->dev);
+    }
+#endif
+    to_fifo = i2c_ll_get_txfifo_len(i2c->dev);
+    if(len < to_fifo){
+        to_fifo = len;
+    }
+    i2c_ll_write_txfifo(i2c->dev, (uint8_t*)buf, to_fifo);
+    buf += to_fifo;
+    len -= to_fifo;
+    //reset tx_queue
+    xQueueReset(i2c->tx_queue);
+    //write the rest of the bytes to the queue
+    if(len){
+        to_queue = uxQueueSpacesAvailable(i2c->tx_queue);
+        if(len < to_queue){
+            to_queue = len;
+        }
+        for (size_t i = 0; i < to_queue; i++) {
+            if (xQueueSend(i2c->tx_queue, &buf[i], timeout_ms / portTICK_RATE_MS) != pdTRUE) {
+                xQueueReset(i2c->tx_queue);
+                to_queue = 0;
+                break;
+            }
+        }
+        //no need to enable TX_EMPTY if tx_queue is empty
+        if(to_queue){
+            i2c_ll_slave_enable_tx_it(i2c->dev);
+        }
+    }
+    I2C_SLAVE_MUTEX_UNLOCK();
+    return to_queue + to_fifo;
+}
+
+//=====================================================================================================================
+//-------------------------------------- Private Functions ------------------------------------------------------------
+//=====================================================================================================================
+
+static void i2c_slave_free_resources(i2c_slave_struct_t * i2c){
+    i2c_slave_detach_gpio(i2c);
+    i2c_ll_set_slave_addr(i2c->dev, 0, false);
+    i2c_ll_disable_intr_mask(i2c->dev, I2C_LL_INTR_MASK);
+    i2c_ll_clr_intsts_mask(i2c->dev, I2C_LL_INTR_MASK);
+
+    if (i2c->intr_handle) {
+        esp_intr_free(i2c->intr_handle);
+        i2c->intr_handle = NULL;
+    }
+
+    if(i2c->task_handle){
+        vTaskDelete(i2c->task_handle);
+        i2c->task_handle = NULL;
+    }
+
+#if I2C_SLAVE_USE_RX_QUEUE
+    if (i2c->rx_queue) {
+        vQueueDelete(i2c->rx_queue);
+        i2c->rx_queue = NULL;
+    }
+#else
+    if (i2c->rx_ring_buf) {
+        vRingbufferDelete(i2c->rx_ring_buf);
+        i2c->rx_ring_buf = NULL;
+    }
+#endif
+
+    if (i2c->tx_queue) {
+        vQueueDelete(i2c->tx_queue);
+        i2c->tx_queue = NULL;
+    }
+
+    if (i2c->event_queue) {
+        vQueueDelete(i2c->event_queue);
+        i2c->event_queue = NULL;
+    }
+
+    i2c->rx_data_count = 0;
+}
+
+static bool i2c_slave_set_frequency(i2c_slave_struct_t * i2c, uint32_t clk_speed)
+{
+    if (i2c == NULL) {
+        log_e("no control buffer");
+        return false;
+    }
+    if(clk_speed > 1100000UL){
+        clk_speed = 1100000UL;
+    }
+
+    // Adjust Fifo thresholds based on frequency
+    uint32_t a = (clk_speed / 50000L) + 2;
+    log_d("Fifo thresholds: rx_fifo_full = %d, tx_fifo_empty = %d", SOC_I2C_FIFO_LEN - a, a);
+
+    i2c_clk_cal_t clk_cal;
+#if SOC_I2C_SUPPORT_APB
+    i2c_ll_cal_bus_clk(APB_CLK_FREQ, clk_speed, &clk_cal);
+    i2c_ll_set_source_clk(i2c->dev, I2C_SCLK_APB);            /*!< I2C source clock from APB, 80M*/
+#elif SOC_I2C_SUPPORT_XTAL
+    i2c_ll_cal_bus_clk(XTAL_CLK_FREQ, clk_speed, &clk_cal);
+    i2c_ll_set_source_clk(i2c->dev, I2C_SCLK_XTAL);           /*!< I2C source clock from XTAL, 40M */
+#endif
+    i2c_ll_set_txfifo_empty_thr(i2c->dev, a);
+    i2c_ll_set_rxfifo_full_thr(i2c->dev, SOC_I2C_FIFO_LEN - a);
+    i2c_ll_set_bus_timing(i2c->dev, &clk_cal);
+    i2c_ll_set_filter(i2c->dev, 3);
+    return true;
+}
+
+static void i2c_slave_delay_us(uint64_t us)
+{
+    uint64_t m = esp_timer_get_time();
+    if (us) {
+        uint64_t e = (m + us);
+        if (m > e) { //overflow
+            while ((uint64_t)esp_timer_get_time() > e);
+        }
+        while ((uint64_t)esp_timer_get_time() < e);
+    }
+}
+
+static void i2c_slave_gpio_mode(int8_t pin, gpio_mode_t mode)
+{
+    gpio_config_t conf = {
+        .pin_bit_mask = 1LL << pin,
+        .mode = mode,
+        .pull_up_en = GPIO_PULLUP_ENABLE,
+        .pull_down_en = GPIO_PULLDOWN_DISABLE,
+        .intr_type = GPIO_INTR_DISABLE
+    };
+    gpio_config(&conf);
+}
+
+static bool i2c_slave_check_line_state(int8_t sda, int8_t scl)
+{
+    if (sda < 0 || scl < 0) {
+        return false;//return false since there is nothing to do
+    }
+    // if the bus is not 'clear' try the cycling SCL until SDA goes High or 9 cycles
+    gpio_set_level(sda, 1);
+    gpio_set_level(scl, 1);
+    i2c_slave_gpio_mode(sda, GPIO_MODE_INPUT | GPIO_MODE_DEF_OD);
+    i2c_slave_gpio_mode(scl, GPIO_MODE_INPUT | GPIO_MODE_DEF_OD);
+    gpio_set_level(scl, 1);
+
+    if (!gpio_get_level(sda) || !gpio_get_level(scl)) { // bus in busy state
+        log_w("invalid state sda(%d)=%d, scl(%d)=%d", sda, gpio_get_level(sda), scl, gpio_get_level(scl));
+        for (uint8_t a=0; a<9; a++) {
+            i2c_slave_delay_us(5);
+            if (gpio_get_level(sda) && gpio_get_level(scl)) { // bus recovered
+                log_w("Recovered after %d Cycles",a);
+                gpio_set_level(sda,0); // start
+                i2c_slave_delay_us(5);
+                for (uint8_t a=0;a<9; a++) {
+                    gpio_set_level(scl,1);
+                    i2c_slave_delay_us(5);
+                    gpio_set_level(scl,0);
+                    i2c_slave_delay_us(5);
+                }
+                gpio_set_level(scl,1);
+                i2c_slave_delay_us(5);
+                gpio_set_level(sda,1); // stop
+                break;
+            }
+            gpio_set_level(scl, 0);
+            i2c_slave_delay_us(5);
+            gpio_set_level(scl, 1);
+        }
+    }
+
+    if (!gpio_get_level(sda) || !gpio_get_level(scl)) { // bus in busy state
+        log_e("Bus Invalid State, Can't init sda=%d, scl=%d",gpio_get_level(sda),gpio_get_level(scl));
+        return false; // bus is busy
+    }
+    return true;
+}
+
+static bool i2c_slave_attach_gpio(i2c_slave_struct_t * i2c, int8_t sda, int8_t scl)
+{
+    if (i2c == NULL) {
+        log_e("no control block");
+        return false;
+    }
+    
+    if ((sda < 0)||( scl < 0)) {
+        log_e("bad pins sda=%d, scl=%d",sda,scl);
+        return false;
+    }
+
+    i2c->scl = scl;
+    gpio_set_level(scl, 1);
+    i2c_slave_gpio_mode(scl, GPIO_MODE_INPUT_OUTPUT_OD);
+    gpio_matrix_out(scl, I2C_SCL_IDX(i2c->num), false, false);
+    gpio_matrix_in(scl, I2C_SCL_IDX(i2c->num), false);
+
+    i2c->sda = sda;
+    gpio_set_level(sda, 1);
+    i2c_slave_gpio_mode(sda, GPIO_MODE_INPUT_OUTPUT_OD);
+    gpio_matrix_out(sda, I2C_SDA_IDX(i2c->num), false, false);
+    gpio_matrix_in(sda, I2C_SDA_IDX(i2c->num), false);
+
+    return true;
+}
+
+static bool i2c_slave_detach_gpio(i2c_slave_struct_t * i2c)
+{
+    if (i2c == NULL) {
+        log_e("no control Block");
+        return false;
+    }
+    if (i2c->scl >= 0) {
+        gpio_matrix_out(i2c->scl, 0x100, false, false);
+        gpio_matrix_in(0x30, I2C_SCL_IDX(i2c->num), false);
+        i2c_slave_gpio_mode(i2c->scl, GPIO_MODE_INPUT);
+        i2c->scl = -1; // un attached
+    }
+    if (i2c->sda >= 0) {
+        gpio_matrix_out(i2c->sda, 0x100, false, false);
+        gpio_matrix_in(0x30, I2C_SDA_IDX(i2c->num), false);
+        i2c_slave_gpio_mode(i2c->sda, GPIO_MODE_INPUT);
+        i2c->sda = -1; // un attached
+    }
+    return true;
+}
+
+static bool i2c_slave_send_event(i2c_slave_struct_t * i2c, i2c_slave_queue_event_t* event)
+{
+    bool pxHigherPriorityTaskWoken = false;
+    if(i2c->event_queue) {
+        if(xQueueSendFromISR(i2c->event_queue, event, (BaseType_t * const)&pxHigherPriorityTaskWoken) != pdTRUE){
+            //log_e("event_queue_full");
+        }
+    }
+    return pxHigherPriorityTaskWoken;
+}
+
+static bool i2c_slave_handle_tx_fifo_empty(i2c_slave_struct_t * i2c)
+{
+    bool pxHigherPriorityTaskWoken = false;
+    uint32_t d = 0, moveCnt = i2c_ll_get_txfifo_len(i2c->dev);
+    while (moveCnt > 0) { // read tx queue until Fifo is full or queue is empty
+        if(xQueueReceiveFromISR(i2c->tx_queue, &d, (BaseType_t * const)&pxHigherPriorityTaskWoken) == pdTRUE){
+            i2c_ll_write_txfifo(i2c->dev, (uint8_t*)&d, 1);
+            moveCnt--;
+        } else {
+            i2c_ll_slave_disable_tx_it(i2c->dev);
+            break;
+        }
+    }
+    return pxHigherPriorityTaskWoken;
+}
+
+static bool i2c_slave_handle_rx_fifo_full(i2c_slave_struct_t * i2c, uint32_t len)
+{
+#if I2C_SLAVE_USE_RX_QUEUE
+    uint32_t d = 0;
+#else
+    uint8_t data[SOC_I2C_FIFO_LEN];
+#endif
+    bool pxHigherPriorityTaskWoken = false;
+#if I2C_SLAVE_USE_RX_QUEUE
+    while (len > 0) {
+        i2c_ll_read_rxfifo(i2c->dev, (uint8_t*)&d, 1);
+        if(xQueueSendFromISR(i2c->rx_queue, &d, (BaseType_t * const)&pxHigherPriorityTaskWoken) != pdTRUE){
+            log_e("rx_queue_full");
+        } else {
+            i2c->rx_data_count++;
+        }
+        if (--len == 0) {
+            len = i2c_ll_get_rxfifo_cnt(i2c->dev);
+        }
+#else
+    if(len){
+        i2c_ll_read_rxfifo(i2c->dev, data, len);
+        if(xRingbufferSendFromISR(i2c->rx_ring_buf, (void*) data, len, (BaseType_t * const)&pxHigherPriorityTaskWoken) != pdTRUE){
+            log_e("rx_ring_buf_full");
+        } else {
+            i2c->rx_data_count += len;
+        }
+#endif
+    }
+    return pxHigherPriorityTaskWoken;
+}
+
+static void i2c_slave_isr_handler(void* arg)
+{
+    bool pxHigherPriorityTaskWoken = false;
+    i2c_slave_struct_t * i2c = (i2c_slave_struct_t *) arg; // recover data
+
+    uint32_t activeInt = i2c_ll_get_intsts_mask(i2c->dev);
+    i2c_ll_clr_intsts_mask(i2c->dev, activeInt);
+    uint8_t rx_fifo_len = i2c_ll_get_rxfifo_cnt(i2c->dev);
+    bool slave_rw = i2c_ll_slave_rw(i2c->dev);
+
+    if(activeInt & I2C_RXFIFO_WM_INT_ENA){ // RX FiFo Full
+        pxHigherPriorityTaskWoken |= i2c_slave_handle_rx_fifo_full(i2c, rx_fifo_len);
+        i2c_ll_slave_enable_rx_it(i2c->dev);//is this necessary?
+    }
+
+    if(activeInt & I2C_TRANS_COMPLETE_INT_ENA){ // STOP
+        if(rx_fifo_len){ //READ RX FIFO
+            pxHigherPriorityTaskWoken |= i2c_slave_handle_rx_fifo_full(i2c, rx_fifo_len);
+        }
+        if(i2c->rx_data_count){ //WRITE or RepeatedStart
+            //SEND RX Event
+            i2c_slave_queue_event_t event;
+            event.event = I2C_SLAVE_EVT_RX;
+            event.stop = !slave_rw;
+            event.param = i2c->rx_data_count;
+            pxHigherPriorityTaskWoken |= i2c_slave_send_event(i2c, &event);
+            //Zero RX count
+            i2c->rx_data_count = 0;
+        }
+        if(slave_rw){ // READ
+#if CONFIG_IDF_TARGET_ESP32
+            if(i2c->dev->status_reg.scl_main_state_last == 6){
+                //SEND TX Event
+                i2c_slave_queue_event_t event;
+                event.event = I2C_SLAVE_EVT_TX;
+                pxHigherPriorityTaskWoken |= i2c_slave_send_event(i2c, &event);
+            }
+#else
+            //reset TX data
+            i2c_ll_txfifo_rst(i2c->dev);
+            uint8_t d;
+            while (xQueueReceiveFromISR(i2c->tx_queue, &d, (BaseType_t * const)&pxHigherPriorityTaskWoken) == pdTRUE) ;//flush partial write
+#endif
+        }
+    }
+
+#ifndef CONFIG_IDF_TARGET_ESP32
+    if(activeInt & I2C_SLAVE_STRETCH_INT_ENA){ // STRETCH
+        i2c_stretch_cause_t cause = i2c_ll_stretch_cause(i2c->dev);
+        if(cause == I2C_STRETCH_CAUSE_MASTER_READ){
+            //on C3 RX data dissapears with repeated start, so we need to get it here
+            if(rx_fifo_len){
+                pxHigherPriorityTaskWoken |= i2c_slave_handle_rx_fifo_full(i2c, rx_fifo_len);
+            }
+            //SEND TX Event
+            i2c_slave_queue_event_t event;
+            event.event = I2C_SLAVE_EVT_TX;
+            pxHigherPriorityTaskWoken |= i2c_slave_send_event(i2c, &event);
+            //will clear after execution
+        } else if(cause == I2C_STRETCH_CAUSE_TX_FIFO_EMPTY){
+            pxHigherPriorityTaskWoken |= i2c_slave_handle_tx_fifo_empty(i2c);
+            i2c_ll_stretch_clr(i2c->dev);
+        } else if(cause == I2C_STRETCH_CAUSE_RX_FIFO_FULL){
+            pxHigherPriorityTaskWoken |= i2c_slave_handle_rx_fifo_full(i2c, rx_fifo_len);
+            i2c_ll_stretch_clr(i2c->dev);
+        }
+    }
+#endif
+
+    if(activeInt & I2C_TXFIFO_WM_INT_ENA){ // TX FiFo Empty
+        pxHigherPriorityTaskWoken |= i2c_slave_handle_tx_fifo_empty(i2c);
+    }
+
+    if(pxHigherPriorityTaskWoken){
+        portYIELD_FROM_ISR();
+    }
+}
+
+static size_t i2c_slave_read_rx(i2c_slave_struct_t * i2c, uint8_t * data, size_t len){
+    if(!len){
+        return 0;
+    }
+#if I2C_SLAVE_USE_RX_QUEUE
+    uint8_t d = 0;
+    BaseType_t res = pdTRUE;
+    for(size_t i=0; i<len; i++) {
+        if(data){
+            res = xQueueReceive(i2c->rx_queue, &data[i], 0);
+        } else {
+            res = xQueueReceive(i2c->rx_queue, &d, 0);
+        }
+        if (res != pdTRUE) {
+            log_e("Read Queue(%u) Failed", i);
+            len = i;
+            break;
+        }
+    }
+    return (data)?len:0;
+#else
+    size_t  dlen = 0, 
+            to_read = len, 
+            so_far = 0, 
+            available = 0;
+    uint8_t * rx_data = NULL;
+
+    vRingbufferGetInfo(i2c->rx_ring_buf, NULL, NULL, NULL, NULL, &available);
+    if(available < to_read){
+        log_e("Less available than requested. %u < %u", available, len);
+        to_read = available;
+    }
+
+    while(to_read){
+        dlen = 0;
+        rx_data = (uint8_t *)xRingbufferReceiveUpTo(i2c->rx_ring_buf, &dlen, 0, to_read);
+        if(!rx_data){
+            log_e("Receive %u Failed", to_read);
+            return so_far;
+        }
+        if(data){
+            memcpy(data+so_far, rx_data, dlen);
+        }
+        vRingbufferReturnItem(i2c->rx_ring_buf, rx_data);
+        so_far+=dlen;
+        to_read-=dlen;
+    }
+    return (data)?so_far:0;
+#endif
+}
+
+static void i2c_slave_task(void *pv_args)
+{
+    i2c_slave_struct_t * i2c = (i2c_slave_struct_t *)pv_args;
+    i2c_slave_queue_event_t event;
+    size_t len = 0;
+    bool stop = false;
+    uint8_t * data = NULL;
+    for(;;){
+        if(xQueueReceive(i2c->event_queue, &event, portMAX_DELAY) == pdTRUE){
+            // Write
+            if(event.event == I2C_SLAVE_EVT_RX){
+                len = event.param;
+                stop = event.stop;
+                data = (len > 0)?(uint8_t*)malloc(len):NULL;
+
+                if(len && data == NULL){
+                    log_e("Malloc (%u) Failed", len);
+                }
+                len = i2c_slave_read_rx(i2c, data, len);
+                if(i2c->receive_callback){
+                    i2c->receive_callback(i2c->num, data, len, stop, i2c->arg);
+                }
+                free(data);
+
+            // Read
+            } else if(event.event == I2C_SLAVE_EVT_TX){
+                if(i2c->request_callback){
+                    i2c->request_callback(i2c->num, i2c->arg);
+                }
+                i2c_ll_stretch_clr(i2c->dev);
+            }
+        }
+    }
+    vTaskDelete(NULL);
+}

src/esp32/hardware/cores/esp32/esp32-hal-i2c-slave.h

@@ -0,0 +1,35 @@
+// Copyright 2015-2021 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "stdint.h"
+#include "stddef.h"
+#include "esp_err.h"
+
+typedef void (*i2c_slave_request_cb_t) (uint8_t num, void * arg);
+typedef void (*i2c_slave_receive_cb_t) (uint8_t num, uint8_t * data, size_t len, bool stop, void * arg);
+esp_err_t i2cSlaveAttachCallbacks(uint8_t num, i2c_slave_request_cb_t request_callback, i2c_slave_receive_cb_t receive_callback, void * arg);
+
+esp_err_t i2cSlaveInit(uint8_t num, int sda, int scl, uint16_t slaveID, uint32_t frequency, size_t rx_len, size_t tx_len);
+esp_err_t i2cSlaveDeinit(uint8_t num);
+size_t i2cSlaveWrite(uint8_t num, const uint8_t *buf, uint32_t len, uint32_t timeout_ms);
+
+#ifdef __cplusplus
+}
+#endif

src/esp32/hardware/cores/esp32/esp32-hal-i2c.c

@@ -0,0 +1,343 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "esp32-hal-i2c.h"
+#include "esp32-hal.h"
+#if !CONFIG_DISABLE_HAL_LOCKS
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "freertos/semphr.h"
+#endif
+#include "esp_attr.h"
+#include "esp_system.h"
+#include "soc/soc_caps.h"
+#include "soc/i2c_periph.h"
+#include "hal/i2c_hal.h"
+#include "hal/i2c_ll.h"
+#include "driver/i2c.h"
+
+typedef volatile struct {
+    bool initialized;
+    uint32_t frequency;
+#if !CONFIG_DISABLE_HAL_LOCKS
+    SemaphoreHandle_t lock;
+#endif
+} i2c_bus_t;
+
+static i2c_bus_t bus[SOC_I2C_NUM];
+
+bool i2cIsInit(uint8_t i2c_num){
+    if(i2c_num >= SOC_I2C_NUM){
+        return false;
+    }
+    return bus[i2c_num].initialized;
+}
+
+esp_err_t i2cInit(uint8_t i2c_num, int8_t sda, int8_t scl, uint32_t frequency){
+    if(i2c_num >= SOC_I2C_NUM){
+        return ESP_ERR_INVALID_ARG;
+    }
+#if !CONFIG_DISABLE_HAL_LOCKS
+    if(bus[i2c_num].lock == NULL){
+        bus[i2c_num].lock = xSemaphoreCreateMutex();
+        if(bus[i2c_num].lock == NULL){
+            log_e("xSemaphoreCreateMutex failed");
+            return ESP_ERR_NO_MEM;
+        }
+    }
+    //acquire lock
+    if(xSemaphoreTake(bus[i2c_num].lock, portMAX_DELAY) != pdTRUE){
+        log_e("could not acquire lock");
+        return ESP_FAIL;
+    }
+#endif
+    if(bus[i2c_num].initialized){
+        log_e("bus is already initialized");
+        return ESP_FAIL;
+    }
+
+    if(!frequency){
+        frequency = 100000UL;
+    } else if(frequency > 1000000UL){
+        frequency = 1000000UL;
+    }
+    log_i("Initialising I2C Master: sda=%d scl=%d freq=%d", sda, scl, frequency);
+
+    i2c_config_t conf = { };
+    conf.mode = I2C_MODE_MASTER;
+    conf.scl_io_num = (gpio_num_t)scl;
+    conf.sda_io_num = (gpio_num_t)sda;
+    conf.scl_pullup_en = GPIO_PULLUP_ENABLE;
+    conf.sda_pullup_en = GPIO_PULLUP_ENABLE;
+    conf.master.clk_speed = frequency;
+    conf.clk_flags = I2C_SCLK_SRC_FLAG_FOR_NOMAL; //Any one clock source that is available for the specified frequency may be choosen
+
+    esp_err_t ret = i2c_param_config((i2c_port_t)i2c_num, &conf);
+    if (ret != ESP_OK) {
+        log_e("i2c_param_config failed");
+    } else {
+        ret = i2c_driver_install((i2c_port_t)i2c_num, conf.mode, 0, 0, 0);
+        if (ret != ESP_OK) {
+            log_e("i2c_driver_install failed");
+        } else {
+            bus[i2c_num].initialized = true;
+            bus[i2c_num].frequency = frequency;
+            //Clock Stretching Timeout: 20b:esp32, 5b:esp32-c3, 24b:esp32-s2
+            i2c_set_timeout((i2c_port_t)i2c_num, I2C_LL_MAX_TIMEOUT);
+        }
+    }
+#if !CONFIG_DISABLE_HAL_LOCKS
+    //release lock
+    xSemaphoreGive(bus[i2c_num].lock);
+#endif
+    return ret;
+}
+
+esp_err_t i2cDeinit(uint8_t i2c_num){
+    esp_err_t err = ESP_FAIL;
+    if(i2c_num >= SOC_I2C_NUM){
+        return ESP_ERR_INVALID_ARG;
+    }
+#if !CONFIG_DISABLE_HAL_LOCKS
+    //acquire lock
+    if(bus[i2c_num].lock == NULL || xSemaphoreTake(bus[i2c_num].lock, portMAX_DELAY) != pdTRUE){
+        log_e("could not acquire lock");
+        return err;
+    }
+#endif
+    if(!bus[i2c_num].initialized){
+        log_e("bus is not initialized");
+    } else {
+        err = i2c_driver_delete((i2c_port_t)i2c_num);
+        if(err == ESP_OK){
+            bus[i2c_num].initialized = false;
+        }
+    }
+#if !CONFIG_DISABLE_HAL_LOCKS
+    //release lock
+    xSemaphoreGive(bus[i2c_num].lock);
+#endif
+    return err;
+}
+
+esp_err_t i2cWrite(uint8_t i2c_num, uint16_t address, const uint8_t* buff, size_t size, uint32_t timeOutMillis){
+    esp_err_t ret = ESP_FAIL;
+    i2c_cmd_handle_t cmd = NULL;
+    if(i2c_num >= SOC_I2C_NUM){
+        return ESP_ERR_INVALID_ARG;
+    }
+#if !CONFIG_DISABLE_HAL_LOCKS
+    //acquire lock
+    if(bus[i2c_num].lock == NULL || xSemaphoreTake(bus[i2c_num].lock, portMAX_DELAY) != pdTRUE){
+        log_e("could not acquire lock");
+        return ret;
+    }
+#endif
+    if(!bus[i2c_num].initialized){
+        log_e("bus is not initialized");
+        goto end;
+    }
+    
+    //short implementation does not support zero size writes (example when scanning) PR in IDF?
+    //ret =  i2c_master_write_to_device((i2c_port_t)i2c_num, address, buff, size, timeOutMillis / portTICK_RATE_MS);
+
+    ret = ESP_OK;
+    uint8_t cmd_buff[I2C_LINK_RECOMMENDED_SIZE(1)] = { 0 };
+    cmd = i2c_cmd_link_create_static(cmd_buff, I2C_LINK_RECOMMENDED_SIZE(1));
+    ret = i2c_master_start(cmd);
+    if (ret != ESP_OK) {
+        goto end;
+    }
+    ret = i2c_master_write_byte(cmd, (address << 1) | I2C_MASTER_WRITE, true);
+    if (ret != ESP_OK) {
+        goto end;
+    }
+    if(size){
+        ret = i2c_master_write(cmd, buff, size, true);
+        if (ret != ESP_OK) {
+            goto end;
+        }
+    }
+    ret = i2c_master_stop(cmd);
+    if (ret != ESP_OK) {
+        goto end;
+    }
+    ret = i2c_master_cmd_begin((i2c_port_t)i2c_num, cmd, timeOutMillis / portTICK_RATE_MS);
+
+end:
+    if(cmd != NULL){
+        i2c_cmd_link_delete_static(cmd);
+    }
+#if !CONFIG_DISABLE_HAL_LOCKS
+    //release lock
+    xSemaphoreGive(bus[i2c_num].lock);
+#endif
+    return ret;
+}
+
+esp_err_t i2cRead(uint8_t i2c_num, uint16_t address, uint8_t* buff, size_t size, uint32_t timeOutMillis, size_t *readCount){
+    esp_err_t ret = ESP_FAIL;
+    if(i2c_num >= SOC_I2C_NUM){
+        return ESP_ERR_INVALID_ARG;
+    }
+#if !CONFIG_DISABLE_HAL_LOCKS
+    //acquire lock
+    if(bus[i2c_num].lock == NULL || xSemaphoreTake(bus[i2c_num].lock, portMAX_DELAY) != pdTRUE){
+        log_e("could not acquire lock");
+        return ret;
+    }
+#endif
+    if(!bus[i2c_num].initialized){
+        log_e("bus is not initialized");
+    } else {
+        ret = i2c_master_read_from_device((i2c_port_t)i2c_num, address, buff, size, timeOutMillis / portTICK_RATE_MS);
+        if(ret == ESP_OK){
+            *readCount = size;
+        } else {
+            *readCount = 0;
+        }
+    }
+#if !CONFIG_DISABLE_HAL_LOCKS
+    //release lock
+    xSemaphoreGive(bus[i2c_num].lock);
+#endif
+    return ret;
+}
+
+esp_err_t i2cWriteReadNonStop(uint8_t i2c_num, uint16_t address, const uint8_t* wbuff, size_t wsize, uint8_t* rbuff, size_t rsize, uint32_t timeOutMillis, size_t *readCount){
+    esp_err_t ret = ESP_FAIL;
+    if(i2c_num >= SOC_I2C_NUM){
+        return ESP_ERR_INVALID_ARG;
+    }
+#if !CONFIG_DISABLE_HAL_LOCKS
+    //acquire lock
+    if(bus[i2c_num].lock == NULL || xSemaphoreTake(bus[i2c_num].lock, portMAX_DELAY) != pdTRUE){
+        log_e("could not acquire lock");
+        return ret;
+    }
+#endif
+    if(!bus[i2c_num].initialized){
+        log_e("bus is not initialized");
+    } else {
+        ret = i2c_master_write_read_device((i2c_port_t)i2c_num, address, wbuff, wsize, rbuff, rsize, timeOutMillis / portTICK_RATE_MS);
+        if(ret == ESP_OK){
+            *readCount = rsize;
+        } else {
+            *readCount = 0;
+        }
+    }
+#if !CONFIG_DISABLE_HAL_LOCKS
+    //release lock
+    xSemaphoreGive(bus[i2c_num].lock);
+#endif
+    return ret;
+}
+
+esp_err_t i2cSetClock(uint8_t i2c_num, uint32_t frequency){
+    esp_err_t ret = ESP_FAIL;
+    if(i2c_num >= SOC_I2C_NUM){
+        return ESP_ERR_INVALID_ARG;
+    }
+#if !CONFIG_DISABLE_HAL_LOCKS
+    //acquire lock
+    if(bus[i2c_num].lock == NULL || xSemaphoreTake(bus[i2c_num].lock, portMAX_DELAY) != pdTRUE){
+        log_e("could not acquire lock");
+        return ret;
+    }
+#endif
+    if(!bus[i2c_num].initialized){
+        log_e("bus is not initialized");
+        goto end;
+    }
+    if(bus[i2c_num].frequency == frequency){
+        ret = ESP_OK;
+        goto end;
+    }
+    if(!frequency){
+        frequency = 100000UL;
+    } else if(frequency > 1000000UL){
+        frequency = 1000000UL;
+    }
+    // Freq limitation when using different clock sources
+    #define I2C_CLK_LIMIT_REF_TICK            (1 * 1000 * 1000 / 20)    /*!< Limited by REF_TICK, no more than REF_TICK/20*/
+    #define I2C_CLK_LIMIT_APB                 (80 * 1000 * 1000 / 20)   /*!< Limited by APB, no more than APB/20*/
+    #define I2C_CLK_LIMIT_RTC                 (20 * 1000 * 1000 / 20)   /*!< Limited by RTC, no more than RTC/20*/
+    #define I2C_CLK_LIMIT_XTAL                (40 * 1000 * 1000 / 20)   /*!< Limited by RTC, no more than XTAL/20*/
+
+    typedef struct {
+        uint8_t character;          /*!< I2C source clock characteristic */
+        uint32_t clk_freq;          /*!< I2C source clock frequency */
+    } i2c_clk_alloc_t;
+
+    // i2c clock characteristic, The order is the same as i2c_sclk_t.
+    static i2c_clk_alloc_t i2c_clk_alloc[I2C_SCLK_MAX] = {
+        {0, 0},
+    #if SOC_I2C_SUPPORT_APB
+        {0, I2C_CLK_LIMIT_APB},                                                                /*!< I2C APB clock characteristic*/
+    #endif
+    #if SOC_I2C_SUPPORT_XTAL
+        {0, I2C_CLK_LIMIT_XTAL},                                                               /*!< I2C XTAL characteristic*/
+    #endif
+    #if SOC_I2C_SUPPORT_RTC
+        {I2C_SCLK_SRC_FLAG_LIGHT_SLEEP | I2C_SCLK_SRC_FLAG_AWARE_DFS, I2C_CLK_LIMIT_RTC},      /*!< I2C 20M RTC characteristic*/
+    #endif
+    #if SOC_I2C_SUPPORT_REF_TICK
+        {I2C_SCLK_SRC_FLAG_AWARE_DFS, I2C_CLK_LIMIT_REF_TICK},                                 /*!< I2C REF_TICK characteristic*/
+    #endif
+    };
+
+    i2c_sclk_t src_clk = I2C_SCLK_DEFAULT;
+    ret = ESP_OK;
+    for (i2c_sclk_t clk = I2C_SCLK_DEFAULT + 1; clk < I2C_SCLK_MAX; clk++) {
+#if CONFIG_IDF_TARGET_ESP32S3
+        if (clk == I2C_SCLK_RTC) { // RTC clock for s3 is unaccessable now.
+            continue;
+        }
+#endif
+        if (frequency <= i2c_clk_alloc[clk].clk_freq) {
+            src_clk = clk;
+            break;
+        }
+    }
+    if(src_clk == I2C_SCLK_MAX){
+        log_e("clock source could not be selected");
+        ret = ESP_FAIL;
+    } else {
+        i2c_hal_context_t hal;
+        hal.dev = I2C_LL_GET_HW(i2c_num);
+        i2c_hal_set_bus_timing(&(hal), frequency, src_clk);
+        bus[i2c_num].frequency = frequency;
+        //Clock Stretching Timeout: 20b:esp32, 5b:esp32-c3, 24b:esp32-s2
+        i2c_set_timeout((i2c_port_t)i2c_num, I2C_LL_MAX_TIMEOUT);
+    }
+
+end:
+#if !CONFIG_DISABLE_HAL_LOCKS
+    //release lock
+    xSemaphoreGive(bus[i2c_num].lock);
+#endif
+    return ret;
+}
+
+esp_err_t i2cGetClock(uint8_t i2c_num, uint32_t * frequency){
+    if(i2c_num >= SOC_I2C_NUM){
+        return ESP_ERR_INVALID_ARG;
+    }
+    if(!bus[i2c_num].initialized){
+        log_e("bus is not initialized");
+        return ESP_FAIL;
+    }
+    *frequency = bus[i2c_num].frequency;
+    return ESP_OK;
+}

src/esp32/hardware/cores/esp32/esp32-hal-i2c.h

@@ -0,0 +1,41 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// modified Nov 2017 by Chuck Todd <StickBreaker> to support Interrupt Driven I/O
+// modified Nov 2021 by Hristo Gochkov <Me-No-Dev> to support ESP-IDF API
+
+#ifndef _ESP32_HAL_I2C_H_
+#define _ESP32_HAL_I2C_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <esp_err.h>
+
+esp_err_t i2cInit(uint8_t i2c_num, int8_t sda, int8_t scl, uint32_t clk_speed);
+esp_err_t i2cDeinit(uint8_t i2c_num);
+esp_err_t i2cSetClock(uint8_t i2c_num, uint32_t frequency);
+esp_err_t i2cGetClock(uint8_t i2c_num, uint32_t * frequency);
+esp_err_t i2cWrite(uint8_t i2c_num, uint16_t address, const uint8_t* buff, size_t size, uint32_t timeOutMillis);
+esp_err_t i2cRead(uint8_t i2c_num, uint16_t address, uint8_t* buff, size_t size, uint32_t timeOutMillis, size_t *readCount);
+esp_err_t i2cWriteReadNonStop(uint8_t i2c_num, uint16_t address, const uint8_t* wbuff, size_t wsize, uint8_t* rbuff, size_t rsize, uint32_t timeOutMillis, size_t *readCount);
+bool i2cIsInit(uint8_t i2c_num);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _ESP32_HAL_I2C_H_ */

src/esp32/hardware/cores/esp32/esp32-hal-ledc.c

@@ -0,0 +1,272 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "esp32-hal.h"
+#include "soc/soc_caps.h"
+#include "driver/ledc.h"
+
+#ifdef SOC_LEDC_SUPPORT_HS_MODE
+#define LEDC_CHANNELS           (SOC_LEDC_CHANNEL_NUM<<1)
+#else
+#define LEDC_CHANNELS           (SOC_LEDC_CHANNEL_NUM)
+#endif
+
+//Use XTAL clock if possible to avoid timer frequency error when setting APB clock < 80 Mhz
+//Need to be fixed in ESP-IDF
+#ifdef SOC_LEDC_SUPPORT_XTAL_CLOCK
+#define LEDC_DEFAULT_CLK        LEDC_USE_XTAL_CLK
+#else
+#define LEDC_DEFAULT_CLK        LEDC_AUTO_CLK
+#endif
+
+#define LEDC_MAX_BIT_WIDTH      SOC_LEDC_TIMER_BIT_WIDE_NUM
+
+/*
+ * LEDC Chan to Group/Channel/Timer Mapping
+** ledc: 0  => Group: 0, Channel: 0, Timer: 0
+** ledc: 1  => Group: 0, Channel: 1, Timer: 0
+** ledc: 2  => Group: 0, Channel: 2, Timer: 1
+** ledc: 3  => Group: 0, Channel: 3, Timer: 1
+** ledc: 4  => Group: 0, Channel: 4, Timer: 2
+** ledc: 5  => Group: 0, Channel: 5, Timer: 2
+** ledc: 6  => Group: 0, Channel: 6, Timer: 3
+** ledc: 7  => Group: 0, Channel: 7, Timer: 3
+** ledc: 8  => Group: 1, Channel: 0, Timer: 0
+** ledc: 9  => Group: 1, Channel: 1, Timer: 0
+** ledc: 10 => Group: 1, Channel: 2, Timer: 1
+** ledc: 11 => Group: 1, Channel: 3, Timer: 1
+** ledc: 12 => Group: 1, Channel: 4, Timer: 2
+** ledc: 13 => Group: 1, Channel: 5, Timer: 2
+** ledc: 14 => Group: 1, Channel: 6, Timer: 3
+** ledc: 15 => Group: 1, Channel: 7, Timer: 3
+*/
+
+uint8_t channels_resolution[LEDC_CHANNELS] = {0};
+
+uint32_t ledcSetup(uint8_t chan, uint32_t freq, uint8_t bit_num)
+{
+    if(chan >= LEDC_CHANNELS || bit_num > LEDC_MAX_BIT_WIDTH){
+        log_e("No more LEDC channels available! (maximum %u) or bit width too big (maximum %u)", LEDC_CHANNELS, LEDC_MAX_BIT_WIDTH);
+        return 0;
+    }
+
+    uint8_t group=(chan/8), timer=((chan/2)%4);
+
+    ledc_timer_config_t ledc_timer = {
+        .speed_mode       = group,
+        .timer_num        = timer,
+        .duty_resolution  = bit_num,
+        .freq_hz          = freq,
+        .clk_cfg          = LEDC_DEFAULT_CLK
+    };
+    if(ledc_timer_config(&ledc_timer) != ESP_OK)
+    {
+        log_e("ledc setup failed!");
+        return 0;
+    }
+    channels_resolution[chan] = bit_num;
+    return ledc_get_freq(group,timer);
+}
+
+void ledcWrite(uint8_t chan, uint32_t duty)
+{
+    if(chan >= LEDC_CHANNELS){
+        return;
+    }
+    uint8_t group=(chan/8), channel=(chan%8);
+
+    //Fixing if all bits in resolution is set = LEDC FULL ON
+    uint32_t max_duty = (1 << channels_resolution[chan]) - 1;
+
+    if((duty == max_duty) && (max_duty != 1)){
+        duty = max_duty + 1;
+    }
+
+    ledc_set_duty(group, channel, duty);
+    ledc_update_duty(group, channel);
+}
+
+uint32_t ledcRead(uint8_t chan)
+{
+    if(chan >= LEDC_CHANNELS){
+        return 0;
+    }
+    uint8_t group=(chan/8), channel=(chan%8);
+    return ledc_get_duty(group,channel);
+}
+
+uint32_t ledcReadFreq(uint8_t chan)
+{
+    if(!ledcRead(chan)){
+        return 0;
+    }
+    uint8_t group=(chan/8), timer=((chan/2)%4);
+    return ledc_get_freq(group,timer);
+}
+
+uint32_t ledcWriteTone(uint8_t chan, uint32_t freq)
+{
+    if(chan >= LEDC_CHANNELS){
+        return 0;
+    }
+    if(!freq){
+        ledcWrite(chan, 0);
+        return 0;
+    }
+
+    uint8_t group=(chan/8), timer=((chan/2)%4);
+
+    ledc_timer_config_t ledc_timer = {
+        .speed_mode       = group,
+        .timer_num        = timer,
+        .duty_resolution  = 10,
+        .freq_hz          = freq, 
+        .clk_cfg          = LEDC_DEFAULT_CLK
+    };
+
+    if(ledc_timer_config(&ledc_timer) != ESP_OK)
+    {
+        log_e("ledcSetup failed!");
+        return 0;
+    }
+    channels_resolution[chan] = 10;
+
+    uint32_t res_freq = ledc_get_freq(group,timer);
+    ledcWrite(chan, 0x1FF);
+    return res_freq;
+}
+
+uint32_t ledcWriteNote(uint8_t chan, note_t note, uint8_t octave){
+    const uint16_t noteFrequencyBase[12] = {
+    //   C        C#       D        Eb       E        F       F#        G       G#        A       Bb        B
+        4186,    4435,    4699,    4978,    5274,    5588,    5920,    6272,    6645,    7040,    7459,    7902
+    };
+
+    if(octave > 8 || note >= NOTE_MAX){
+        return 0;
+    }
+    uint32_t noteFreq =  (uint32_t)noteFrequencyBase[note] / (uint32_t)(1 << (8-octave));
+    return ledcWriteTone(chan, noteFreq);
+}
+
+void ledcAttachPin(uint8_t pin, uint8_t chan)
+{
+    if(chan >= LEDC_CHANNELS){
+        return;
+    }
+    uint8_t group=(chan/8), channel=(chan%8), timer=((chan/2)%4);
+    uint32_t duty = ledc_get_duty(group,channel);
+
+    ledc_channel_config_t ledc_channel = {
+        .speed_mode     = group,
+        .channel        = channel,
+        .timer_sel      = timer,
+        .intr_type      = LEDC_INTR_DISABLE,
+        .gpio_num       = pin,
+        .duty           = duty,
+        .hpoint         = 0
+    };
+    ledc_channel_config(&ledc_channel);
+}
+
+void ledcDetachPin(uint8_t pin)
+{
+    pinMatrixOutDetach(pin, false, false);
+}
+
+uint32_t ledcChangeFrequency(uint8_t chan, uint32_t freq, uint8_t bit_num)
+{
+    if(chan >= LEDC_CHANNELS || bit_num > LEDC_MAX_BIT_WIDTH){
+        log_e("LEDC channel not available! (maximum %u) or bit width too big (maximum %u)", LEDC_CHANNELS, LEDC_MAX_BIT_WIDTH);
+        return 0;
+    }
+    uint8_t group=(chan/8), timer=((chan/2)%4);
+
+    ledc_timer_config_t ledc_timer = {
+        .speed_mode       = group,
+        .timer_num        = timer,
+        .duty_resolution  = bit_num,
+        .freq_hz          = freq, 
+        .clk_cfg          = LEDC_DEFAULT_CLK
+    };
+
+    if(ledc_timer_config(&ledc_timer) != ESP_OK)
+    {
+        log_e("ledcChangeFrequency failed!");
+        return 0;
+    }
+    channels_resolution[chan] = bit_num;
+    return ledc_get_freq(group,timer);
+}
+
+static int8_t pin_to_channel[SOC_GPIO_PIN_COUNT] = { 0 };
+static int cnt_channel = LEDC_CHANNELS;
+static uint8_t analog_resolution = 8;
+static int analog_frequency = 1000;
+void analogWrite(uint8_t pin, int value) {
+    // Use ledc hardware for internal pins
+    if (pin < SOC_GPIO_PIN_COUNT) {
+        int8_t channel = -1;
+        if (pin_to_channel[pin] == 0) {
+            if (!cnt_channel) {
+                log_e("No more analogWrite channels available! You can have maximum %u", LEDC_CHANNELS);
+                return;
+            }
+            cnt_channel--;
+            channel = cnt_channel;
+        } else {
+            channel = analogGetChannel(pin);
+        }
+        log_v("GPIO %d - Using Channel %d, Value = %d", pin, channel, value);
+        if(ledcSetup(channel, analog_frequency, analog_resolution) == 0){
+            log_e("analogWrite setup failed (freq = %u, resolution = %u). Try setting different resolution or frequency");
+            return;
+        }
+        ledcAttachPin(pin, channel);
+        pin_to_channel[pin] = channel + 1;
+        ledcWrite(channel, value);
+    }
+}
+
+int8_t analogGetChannel(uint8_t pin) {
+    return pin_to_channel[pin] - 1;
+}
+
+void analogWriteFrequency(uint32_t freq) {
+    if (cnt_channel != LEDC_CHANNELS) {
+        for (int channel = LEDC_CHANNELS - 1; channel >= cnt_channel; channel--) {
+            if (ledcChangeFrequency(channel, freq, analog_resolution) == 0){
+                log_e("analogWrite frequency cant be set due to selected resolution! Try to adjust resolution first");
+                return;
+            }
+        }
+    }
+    analog_frequency = freq;
+}
+
+void analogWriteResolution(uint8_t bits) {
+    if(bits > LEDC_MAX_BIT_WIDTH) {
+        log_w("analogWrite resolution width too big! Setting to maximum %u bits)", LEDC_MAX_BIT_WIDTH);
+        bits = LEDC_MAX_BIT_WIDTH;
+    }
+    if (cnt_channel != LEDC_CHANNELS) {
+        for (int channel = LEDC_CHANNELS - 1; channel >= cnt_channel; channel--) {
+            if (ledcChangeFrequency(channel, analog_frequency, bits) == 0){
+                log_e("analogWrite resolution cant be set due to selected frequency! Try to adjust frequency first");
+                return;
+            }
+        }
+    }
+    analog_resolution = bits;
+}

src/esp32/hardware/cores/esp32/esp32-hal-ledc.h

@@ -0,0 +1,45 @@
+// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _ESP32_HAL_LEDC_H_
+#define _ESP32_HAL_LEDC_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+#include <stdbool.h>
+
+typedef enum {
+    NOTE_C, NOTE_Cs, NOTE_D, NOTE_Eb, NOTE_E, NOTE_F, NOTE_Fs, NOTE_G, NOTE_Gs, NOTE_A, NOTE_Bb, NOTE_B, NOTE_MAX
+} note_t;
+
+//channel 0-15 resolution 1-16bits freq limits depend on resolution
+uint32_t    ledcSetup(uint8_t channel, uint32_t freq, uint8_t resolution_bits);
+void        ledcWrite(uint8_t channel, uint32_t duty);
+uint32_t    ledcWriteTone(uint8_t channel, uint32_t freq);
+uint32_t    ledcWriteNote(uint8_t channel, note_t note, uint8_t octave);
+uint32_t    ledcRead(uint8_t channel);
+uint32_t    ledcReadFreq(uint8_t channel);
+void        ledcAttachPin(uint8_t pin, uint8_t channel);
+void        ledcDetachPin(uint8_t pin);
+uint32_t    ledcChangeFrequency(uint8_t channel, uint32_t freq, uint8_t resolution_bits);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _ESP32_HAL_LEDC_H_ */