A camera communication protocol verification CRC program

programing language ：c Language

According to the set algorithm rules , Input string , Calculated calibration data ;

The code is as follows ：

#include <stdio.h> 
int main(void) 
{ 
	//unsigned char ptr[31] = {0xAA ,0x1F ,0x08 ,0x01 ,0x00 ,0x00 ,0x00 ,0x00 ,0x00 ,0x00 ,0x00 ,0x00 ,0x2B ,0xD8 ,0xF9 ,0xFF ,0xFF ,0xA0 ,0xB3 ,0x01 ,0x00 ,0x56 ,0xD2 ,0x04 ,0x00 ,0x00 ,0x3F ,0x3C ,0x34 ,0x01,0x00};
	unsigned char ptr[31] = {0xAA ,0x1F ,0x08 ,0x01 ,0x00 ,0x00 ,0x00 ,0x00 ,0x00 ,0x00 ,0x00 ,0x00 ,0x2B ,0xEF ,0x04 ,0x00 ,0x00 ,0xA0 ,0xB3 ,0x01 ,0x00 ,0x56 ,0xD2 ,0x04 ,0x00 ,0x00 ,0x3F ,0x3C ,0x34 ,0x01,0x00};
	unsigned char i ,len; 
	unsigned char t = 0; 
	unsigned char crc = 0x00; 
	len = sizeof(ptr);
	// The last bit is reserved for the check bit  
	int len_t=len-1; 
	while(len_t--) 
	{ 
		crc ^= ptr[t++]; 
		for (i=8; i>0; --i) 
		{ 
			if (crc & 0x80) 
			{ 
				crc = (crc << 1) ^ 0xD5; 
			}
			else
				crc = (crc << 1); 
		} 
	}
	printf("crc = 0x%x \n",crc); 
	ptr[len-1] = crc;
	for(i=0;i<len;i++) 
	{ 
		printf("[%02X]",ptr[i]);
	}
}

The operation results are as follows ：