crc.c

来自「数组为8位char型数值」· C语言 代码 · 共 28 行

crc16_update(unsigned int crc, unsigned char a)
    {
	int i;

	crc ^= a;
	for (i = 0; i < 8; ++i)
	{
	    if (crc & 1)
		crc = (crc >> 1) ^ 0xA001;
	    else
		crc = (crc >> 1);
	}

	return crc;
    }


unsigned int  usCRC16( unsigned char * pucFrame, unsigned char usLen )
{
	unsigned int  crc_temp = 0xffff;
	while( usLen )
	{
		crc_temp = crc16_update( crc_temp, *pucFrame++ );
		--usLen;
	}
	return crc_temp;
}