CRC x8 + x2 + x + 1校验_x8+x2+x+1-优快云博客

本文链接：https://blog.youkuaiyun.com/Btefuliycomputer/article/details/101391042

本文详细介绍了一种CRC8校验算法的C++实现过程，包括算法原理、代码解析及应用示例。通过四个不同数据集的测试，验证了算法的有效性和准确性。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

参考：https://blog.youkuaiyun.com/liwei16611/article/details/86704451(这位大哥写的挺好的，大家可以优先学习)

手册中的参数定义：

本实验采用以上CRC标准。

#include <iostream>
using namespace std;
unsigned char  crc_8(unsigned char* const pstr,int length);
int main(){
//四组数据，前20字节为数据位，21位为CRC校验位
	unsigned char str[] = {0xA8,0xFF,0xFF,0xBE,0x00,0x00,0x01,0x00,0x00,0x76,0x00,0x2A,0x20,0x2A,0x40,0x2A,0x20,0x97,0x02,0x06,0xEA};
	unsigned char st2[] = {0xA8,0xFF,0xFF,0xBE,0x00,0x00,0x09,0x00,0x00,0x7B,0x00,0x2A,0x00,0x2A,0x60,0x2A,0x40,0x9B,0x02,0x07,0xB1};
	unsigned char st3[] = {0xA8,0xFF,0xFF,0x75,0xFF,0xFF,0xDC,0x00,0x00,0x99,0x00,0x2B,0x60,0x2B,0x80,0x2B,0x60,0xAD,0x02,0x07,0x38};
	unsigned char st4[] = {0xA8,0xFF,0xFF,0x7E,0xFF,0xFF,0xF9,0x00,0x00,0x7A,0x00,0x2C,0xC0,0x2C,0xC0,0x2C,0xC0,0xB7,0x02,0x07,0x49};
	if(crc_8(st3,20)  == 0x38){
		cout<<"true";
	}
	return 0;
} 

unsigned char  crc_8(unsigned char*  const pstr,int length){
	unsigned char* p= pstr;
	int len = length;
	unsigned char crc = 0xff;//根据自己实际情况或者手册中初值
	
	unsigned char i = 0;
	while(len--){
		crc ^= *p++;
		for(i = 8 ; i > 0 ; --i){
			if(crc & 0x80){					//判断最高位是不是为1 
				crc =  (crc << 1)^ 0x07; 	/* 最高位为1，不需要异或，往左移一位，然后与0x31异或 */
			}else{
				crc = (crc << 1); 
			} 
		} 
	} 
	return crc;
}