29 lines
662 B
C
29 lines
662 B
C
#ifndef CRC16_H
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#define CRC16_H
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#if defined(ARDUINO) && ARDUINO >= 100
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#include "Arduino.h"
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#else
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#include "WProgram.h"
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#endif
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unsigned int CRC16(unsigned int crc, unsigned char *buf, int len)
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{
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for (int pos = 0; pos < len; pos++)
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{
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crc ^= (unsigned int)buf[pos]; // XOR byte into least sig. byte of crc
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for (int i = 8; i != 0; i--) { // Loop over each bit
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if ((crc & 0x0001) != 0) { // If the LSB is set
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crc >>= 1; // Shift right and XOR 0xA001
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crc ^= 0xA001;
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}
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else // Else LSB is not set
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crc >>= 1; // Just shift right
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}
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}
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return crc;
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}
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#endif
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