IBASE Technology SE-602-N, Руководство пользователя

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SE-602-N User Manual
1.2.3 CRC
Protocol uses 16-bit CCITT CRC to verify data integrity.
P(x) = X
16
+X
12
+X
5
+1.
unsigned calc_crc( unsigned char *data, unsigned n, unsigned start) {
unsigned I, k, q, c, crcval;
crcval=start;
for (I=0; I<n; I++) {
c=data(I) & 0xFF;
q=(crcval^c) & 0x0F;
crcval=(crcval>>4)^(q*0x1081);
}
return crcval;
}