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42 lines
1011 B
42 lines
1011 B
6 years ago
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'use strict';
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Object.defineProperty(exports, "__esModule", {
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value: true
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});
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var _buffer = require('buffer');
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var _create_buffer = require('./create_buffer');
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var _create_buffer2 = _interopRequireDefault(_create_buffer);
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var _define_crc = require('./define_crc');
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var _define_crc2 = _interopRequireDefault(_define_crc);
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function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
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var crc16xmodem = (0, _define_crc2.default)('xmodem', function (buf, previous) {
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if (!_buffer.Buffer.isBuffer(buf)) buf = (0, _create_buffer2.default)(buf);
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var crc = typeof previous !== 'undefined' ? ~~previous : 0x0;
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for (var index = 0; index < buf.length; index++) {
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var byte = buf[index];
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var code = crc >>> 8 & 0xff;
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code ^= byte & 0xff;
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code ^= code >>> 4;
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crc = crc << 8 & 0xffff;
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crc ^= code;
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code = code << 5 & 0xffff;
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crc ^= code;
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code = code << 7 & 0xffff;
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crc ^= code;
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}
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return crc;
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});
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exports.default = crc16xmodem;
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