C语言 CRC-8 （X^7+X^6+X^5+X^2+1）校验

CRC-8校验示例代码：

#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

//获取长度
size_t calculateLength(uint8_t *temp)
{
    size_t len = 0;
    while (temp[len] != '\0')
    {
        len++;
    }
    return len;
}

//字符串转uint8_t*
uint8_t* charToUint8(char* data) {
    int len = strlen(data);
    uint8_t* result = (uint8_t*)malloc(len / 2);
    
    for (int i = 0; i < len; i += 2) {
        sscanf(data + i, "%2hhx", &result[i / 2]);
    }
    
    return result;
}

uint8_t crc8(uint8_t *data, int len)
{
    uint8_t crc = 0;
    uint8_t poly = 0xE5; // 多项式 X^7 + X^6 + X^5 + X^2 + 1 对应的十六进制表示

    for (int i = 0; i < len; i++)
    {
        crc ^= data[i];
        for (int j = 0; j < 8; j++)
        {
            if (crc & 0x80)
            {
                crc = (crc << 1) ^ poly;
            }
            else
            {
                crc <<= 1;
            }
        }
    }
    return crc;
}

//测试
int main(int argc, char *argv[])
{
    if (argc <= 1)
    {
        return 0;
    }
    uint8_t *data = charToUint8(argv[1]);
    int len = calculateLength(argv[1])/2;
    uint8_t crc7 = crc8(data, len);

    printf("******\n");
    for(int i = 0;i<len;i++){
        printf("%.2x ", data[i]);
    }
    printf("\ncrc7 = %x\n******\n", crc7);

    return 1;
}

运行结果：