30 lines
625 B
JavaScript
30 lines
625 B
JavaScript
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// Generated by CoffeeScript 1.9.2
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var Buffer, create;
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Buffer = require('buffer').Buffer;
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create = require('./create');
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module.exports = create('xmodem', function(buf, previous) {
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var code, count, crc, i;
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if (!Buffer.isBuffer(buf)) {
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buf = Buffer(buf);
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}
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crc = previous != null ? ~~previous : 0x0;
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count = buf.length;
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i = 0;
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while (count > 0) {
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code = crc >>> 8 & 0xFF;
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code ^= buf[i++] & 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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count--;
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}
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return crc;
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});
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