johill

def crc (crc_calc, bt_to_crc, poly):        al = bt_to_crc        c = 0 #Boolean value        bl = 0        for bl in range(8,0,-1):                al ^= crc_calc                c = (al & 0x01) != 0                al = crc_calc                if(c): al ^= 0xce                al >>= 1                if(c): al |= 0x80                crc_calc = al                al = bt_to_crc                al >>= 1                bt_to_crc = al        return crc_calcdef crc_bytes(bytes, poly):        # initial value is 0xFF        c = 0xFF        for i in range(0,len(bytes)):                c = crc(c, bytes[i], poly)        return c