TELINK SEMICONDUCTOR TLSR8232 - Appendix; Appendix 1: Crc16 Algorithm

Telink TLSR8232 BLE SDK Developer Handbook
AN-19112700-E1 210 Ver.1.0.0
Appendix
Appendix 1: crc16 Algorithm
unsigned shortcrc16 (unsigned char *pD, int len)
{
static unsigned short poly[2]={0, 0xa001};
unsigned short crc = 0xffff;
unsigned char ds;
int i,j;
for(j=len; j>0; j--)
{
unsigned char ds = *pD++;
for(i=0; i<8; i++)
{
crc = (crc >> 1) ^ poly[(crc ^ ds ) & 1];
ds = ds >> 1;
}
}
return crc;
}