mirror of https://github.com/arendst/Tasmota.git
30 lines
539 B
C++
30 lines
539 B
C++
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#include "crc.h"
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uint16_t AMS_crc16_x25(const uint8_t* p, int len)
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{
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uint16_t crc = UINT16_MAX;
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while(len--)
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for (uint16_t i = 0, d = 0xff & *p++; i < 8; i++, d >>= 1)
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crc = ((crc & 1) ^ (d & 1)) ? (crc >> 1) ^ 0x8408 : (crc >> 1);
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return (~crc << 8) | (~crc >> 8 & 0xff);
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}
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uint16_t AMS_crc16 (const uint8_t *p, int len) {
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uint16_t crc = 0;
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while (len--) {
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int i;
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crc ^= *p++;
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for (i = 0 ; i < 8 ; ++i) {
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if (crc & 1)
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crc = (crc >> 1) ^ 0xa001;
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else
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crc = (crc >> 1);
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}
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}
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return crc;
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}
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