CRC-8/MAXIM check algorithm (implemented in C language)

  CRC, the full name of "Cyclic Redundancy Check, is cyclic redundancy check. It is a channel coding technology commonly used in detecting or verifying data. In fact, it is a short check code generated from the original data, such as CRC8, CRC8 /MAXIM, CRC16/MAXIM, CRC32, etc. The following introduces some commonly used C language implementation methods for generating CRC check codes.

CRC-8 / MAXIMUM	(Lol)
Parametric model name	x 8+x5+x4+1
Width WIDTH	8
Polynomial POLY	0x31
Initial value INIT	0x00
Result or value XOROU	0x00
Input data inversion REFIN	YES
Output data inversion REFOUT	YES

PART algorithm implementation

uint8_t crc8_MAXIM(uint8_t *data, uint8_t len)
{
    
    
    uint8_t crc, i;
    crc = 0x00;

    while(len--)
    {
    
    
        crc ^ = *data++;
        for(i = 0;i < 8;i++)
        {
    
    
            if(crc & 0x01)
            {
    
    
                crc = (crc >> 1) ^ 0x8c;
            }
                else crc >>= 1;
        }
    }
    return crc;
}

PS: By the way, an algorithm for exchanging the high and low bits of Byte (butterfly exchange method) is attached.
PART algorithm implementation

uint8_t Byte_shift(uint8_t data)
{
    
    
    data = (data << 4)|(data >> 4);
    data = ((data << 2) & 0xcc) | ((data >> 2) & 0x33);
    data = ((data << 1) & 0xaa) | ((data >> 1) & 0x55);
    
    return data;
}

  the above.