CRC8使用记录

CRC8使用记录

• 写法1

uint8_t check_crc8( uint8_t *data_d, uint16_t size )
{
    uint8_t crc = 0;
	uint8_t i=0;
	
    if(size <= 0)
    {
        return crc;
    }
	
    while( size-- )
    {
		//SYS_TEST("*data_d=%x \r\n",*data_d);
		
        for (  i = 0x80; i != 0; i /= 2 )
        {
			SYS_TEST("i=%d \r\n",i);
			
            if ( (crc & 0x80) != 0)
            {
                crc *= 2;
                crc ^= 0x07; 
            }
            else
            {
                crc *= 2;
            }
 			
            if ( (*data_d & i) != 0 )
            {
                crc ^= 0x07;
            }
        }
        data_d++;
    }
	SYS_TEST("crc=%x \r\n",crc);
    return crc;
}

• 写法2（推荐）

uint8_t crc8_crc8(uint8_t *data, int size)
{
    uint8_t crc = 0x00;
    uint8_t bit =0;

    while (size--)
    {
        crc ^= *data++;
        for (bit = 0; bit < 8; bit++)
        {
            if (crc & 0x80)
            {
                crc = (crc << 1) ^ 0x07;
            }
            else
            {
                crc <<= 1;
            }
        }
    }
	SYS_TEST("crc=%x \r\n",crc);	
    return crc;
}

• 测试结果
  

测试结果
数据 0x01,0x02,0x03,0x04,0x05
crc8=bc
证明计算是正确的

分享链接
https://blog.youkuaiyun.com/dop102/article/details/102930247