Danfoss MODBUS CRC16 calculate

uint16_t crc16(uint8_t *adr_buffer, uint32_t byte_cnt)
{
    static unsigned char auchCRCHi[]=
    {
        0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,
        0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,
        0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,
        0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,
        0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,
        0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,
        0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,
        0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,
        0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,
        0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,
        0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,
        0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,
        0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,
        0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,
        0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,
        0x00,0xC1,0x81,0x40,0x01,0xC0,0x80,0x41,0x01,0xC0,0x80,0x41,0x00,0xC1,0x81,0x40,
    };
    /*Table of CRC values for low–order byte*/
    static char auchCRCLo[]=
    {
        0x00,0xC0,0xC1,0x01,0xC3,0x03,0x02,0xC2,0xC6,0x06,0x07,0xC7,0x05,0xC5,0xC4,0x04,
        0xCC,0x0C,0x0D,0xCD,0x0F,0xCF,0xCE,0x0E,0x0A,0xCA,0xCB,0x0B,0xC9,0x09,0x08,0xC8,
        0xD8,0x18,0x19,0xD9,0x1B,0xDB,0xDA,0x1A,0x1E,0xDE,0xDF,0x1F,0xDD,0x1D,0x1C,0xDC,
        0x14,0xD4,0xD5,0x15,0xD7,0x17,0x16,0xD6,0xD2,0x12,0x13,0xD3,0x11,0xD1,0xD0,0x10,
        0xF0,0x30,0x31,0xF1,0x33,0xF3,0xF2,0x32,0x36,0xF6,0xF7,0x37,0xF5,0x35,0x34,0xF4,
        0x3C,0xFC,0xFD,0x3D,0xFF,0x3F,0x3E,0xFE,0xFA,0x3A,0x3B,0xFB,0x39,0xF9,0xF8,0x38,
        0x28,0xE8,0xE9,0x29,0xEB,0x2B,0x2A,0xEA,0xEE,0x2E,0x2F,0xEF,0x2D,0xED,0xEC,0x2C,
        0xE4,0x24,0x25,0xE5,0x27,0xE7,0xE6,0x26,0x22,0xE2,0xE3,0x23,0xE1,0x21,0x20,0xE0,
        0xA0,0x60,0x61,0xA1,0x63,0xA3,0xA2,0x62,0x66,0xA6,0xA7,0x67,0xA5,0x65,0x64,0xA4,
        0x6C,0xAC,0xAD,0x6D,0xAF,0x6F,0x6E,0xAE,0xAA,0x6A,0x6B,0xAB,0x69,0xA9,0xA8,0x68,
        0x78,0xB8,0xB9,0x79,0xBB,0x7B,0x7A,0xBA,0xBE,0x7E,0x7F,0xBF,0x7D,0xBD,0xBC,0x7C,
        0xB4,0x74,0x75,0xB5,0x77,0xB7,0xB6,0x76,0x72,0xB2,0xB3,0x73,0xB1,0x71,0x70,0xB0,
        0x50,0x90,0x91,0x51,0x93,0x53,0x52,0x92,0x96,0x56,0x57,0x97,0x55,0x95,0x94,0x54,
        0x9C,0x5C,0x5D,0x9D,0x5F,0x9F,0x9E,0x5E,0x5A,0x9A,0x9B,0x5B,0x99,0x59,0x58,0x98,
        0x88,0x48,0x49,0x89,0x4B,0x8B,0x8A,0x4A,0x4E,0x8E,0x8F,0x4F,0x8D,0x4D,0x4C,0x8C,
        0x44,0x84,0x85,0x45,0x87,0x47,0x46,0x86,0x82,0x42,0x43,0x83,0x41,0x81,0x80,0x40,
    };

    unsigned char uchCRCHi = 0xFF;
    unsigned char uchCRCLo = 0xFF;
    unsigned uIndex;
 
    /* CRC Generation Function */
    while( byte_cnt--) /* pass through message buffer */
    {
        uIndex = uchCRCHi ^ *adr_buffer++; /* calculate the CRC */
        uchCRCHi = uchCRCLo ^ auchCRCHi[uIndex];
        uchCRCLo = auchCRCLo[uIndex];
    }
return (uchCRCHi << 8 | uchCRCLo);
}

        crc_hi = 0xFF;   // high byte of CRC initialized
        crc_lo = 0xFF;   // low byte of CRC initialized

        do
        {
           uint8_t i = crc_hi ^ *p++;        // will index into CRC lookup table
           crc_hi = crc_lo ^ (uint8_t)(&auchCRCHi[i]);    // calculate the CRC
           crc_lo =          (uint8_t)(&auchCRCLo[i]);
        }
        while (--n);         // pass through message buffer (max 256 items)

auchCRCHi:
; High
.db 0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41, 0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40, 0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40, 0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41
.db 0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40, 0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41, 0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41, 0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40 .db 0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40, 0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41, 0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41, 0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40
.db 0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41, 0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40, 0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40, 0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41
.db 0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40, 0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41, 0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41, 0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40
.db 0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41, 0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40, 0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40, 0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41
.db 0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41, 0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40, 0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40, 0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41
.db 0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40, 0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41, 0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41, 0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40
; Low 
auchCRCLo:
.db 0x00,0xc0,0xc1,0x01,0xc3,0x03,0x02,0xc2, 0xc6,0x06,0x07,0xc7,0x05,0xc5,0xc4,0x04, 0xcc,0x0c,0x0d,0xcd,0x0f,0xcf,0xce,0x0e, 0x0a,0xca,0xcb,0x0b,0xc9,0x09,0x08,0xc8
.db 0xd8,0x18,0x19,0xd9,0x1b,0xdb,0xda,0x1a, 0x1e,0xde,0xdf,0x1f,0xdd,0x1d,0x1c,0xdc, 0x14,0xd4,0xd5,0x15,0xd7,0x17,0x16,0xd6, 0xd2,0x12,0x13,0xd3,0x11,0xd1,0xd0,0x10
.db 0xf0,0x30,0x31,0xf1,0x33,0xf3,0xf2,0x32, 0x36,0xf6,0xf7,0x37,0xf5,0x35,0x34,0xf4, 0x3c,0xfc,0xfd,0x3d,0xff,0x3f,0x3e,0xfe, 0xfa,0x3a,0x3b,0xfb,0x39,0xf9,0xf8,0x38
.db 0x28,0xe8,0xe9,0x29,0xeb,0x2b,0x2a,0xea, 0xee,0x2e,0x2f,0xef,0x2d,0xed,0xec,0x2c, 0xe4,0x24,0x25,0xe5,0x27,0xe7,0xe6,0x26, 0x22,0xe2,0xe3,0x23,0xe1,0x21,0x20,0xe0
.db 0xa0,0x60,0x61,0xa1,0x63,0xa3,0xa2,0x62, 0x66,0xa6,0xa7,0x67,0xa5,0x65,0x64,0xa4, 0x6c,0xac,0xad,0x6d,0xaf,0x6f,0x6e,0xae, 0xaa,0x6a,0x6b,0xab,0x69,0xa9,0xa8,0x68
.db 0x78,0xb8,0xb9,0x79,0xbb,0x7b,0x7a,0xba, 0xbe,0x7e,0x7f,0xbf,0x7d,0xbd,0xbc,0x7c, 0xb4,0x74,0x75,0xb5,0x77,0xb7,0xb6,0x76, 0x72,0xb2,0xb3,0x73,0xb1,0x71,0x70,0xb0
.db 0x50,0x90,0x91,0x51,0x93,0x53,0x52,0x92, 0x96,0x56,0x57,0x97,0x55,0x95,0x94,0x54, 0x9c,0x5c,0x5d,0x9d,0x5f,0x9f,0x9e,0x5e, 0x5a,0x9a,0x9b,0x5b,0x99,0x59,0x58,0x98
.db 0x88,0x48,0x49,0x89,0x4b,0x8b,0x8a,0x4a, 0x4e,0x8e,0x8f,0x4f,0x8d,0x4d,0x4c,0x8c, 0x44,0x84,0x85,0x45,0x87,0x47,0x46,0x86, 0x82,0x42,0x43,0x83,0x41,0x81,0x80,0x40