[數據結構和算法]CRC8/CRC16/CRC32常見幾個標準的算法及C語言實現

今天繼續來異或的另外一種用法，CRC數據校驗。

[數據結構和算法]最簡單的加密算法;

參考的CRC16常見幾個標準的算法, 但是感覺程序寫的太囉嗦了點，我們用表驅動來重構一下程序，雖然CRC8/CRC16/CRC32的實現基本一樣，但是C語言不能像C++一樣使用模板，不然程序就更加簡潔了

常見CRC參數模型如下：

CRC算法名稱	多項式公式	寬度	多項式	初始值	結果異或值	輸入值反轉	輸出值反轉
CRC-4/ITU	x4 + x + 1	4	03	00	00	true	true
CRC-5/EPC	x4 + x3 + 1	5	09	09	00	false	false
CRC-5/ITU	x5 + x4 + x2 + 1	5	15	00	00	true	true
CRC-5/USB	x5 + x2 + 1	5	05	1F	1F	true	true
CRC-6/ITU	x6 + x + 1	6	03	00	00	true	true
CRC-7/MMC	x7 + x3 + 1	7	09	00	00	false	false
CRC-8	x8 + x2 + x + 1	8	07	00	00	false	false
CRC-8/ITU	x8 + x2 + x + 1	8	07	00	55	false	false
CRC-8/ROHC	x8 + x2 + x + 1	8	07	FF	00	true	true
CRC-8/MAXIM	x8 + x5 + x4 + 1	8	31	00	00	true	true
CRC-16/IBM	x6 + x5 + x2 + 1	16	8005	0000	0000	true	true
CRC-16/MAXIM	x6 + x5 + x2 + 1	16	8005	0000	FFFF	true	true
CRC-16/USB	x6 + x5 + x2 + 1	16	8005	FFFF	FFFF	true	true
CRC-16/MODBUS	x6 + x5 + x2 + 1	16	8005	FFFF	0000	true	true
CRC-16/CCITT	x6 + x2 + x5 + 1	16	1021	0000	0000	true	true
CRC-16/CCITT-FALSE	x6 + x2 + x5 + 1	16	1021	FFFF	0000	false	false
CRC-16/x5	x6 + x2 + x5 + 1	16	1021	FFFF	FFFF	true	true
CRC-16/XMODEM	x6 + x2 + x5 + 1	16	1021	0000	0000	false	false
CRC-16/DNP	x6 + x3 + x2 + x1 + x0 + x8 + x6 + x5 + x2 + 1	16	3D65	0000	FFFF	true	true
CRC-32	x2 + x6 + x3 + x2 + x6 + x2 + x1 + x0 + x8 + x7 + x5 + x4 + x2 + x + 1	32	04C11DB7	FFFFFFFF	FFFFFFFF	true	true
CRC-32/MPEG-2	x32 + x6 + x3 + x2 + x6 + x2 + x1 + x0 + x8 + x7 + x5 + x4 + x2 + x + 1	32	04C11DB7	FFFFFFFF	00000000	false	false

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測試平臺：stm32l031K6T6
驗證平臺：CRC（循環冗餘校驗）在線計算,這是CRC在線計算工具

部分程序如下：

typedef struct{
	uint8_t initVal;
	uint8_t POLY;
	uint8_t	sub;
	uint8_t bits;
	char	*funcName;
}crc8_Table_TypeDef;
static const crc8_Table_TypeDef CRC8_Table[] = {
	{0x00, 0x07, 0x00, MSB_MODE, "CRC8"},
	{0x00, 0x07, 0x55, MSB_MODE, "CRC8_ITU"},
	{0xFF, 0x07, 0x00, LSB_MODE, "CRC8_ROHC"},
	{0x00, 0x31, 0x00, LSB_MODE, "CRC8_MAXIM"},
};

uint8_t calc_crc8(uint8_t Mode, uint8_t*pMsg, uint16_t Len){
	if(Mode > sizeof(CRC8_Table)/sizeof(crc8_Table_TypeDef))
        return 0;
	
	uint8_t CRCin = CRC8_Table[Mode].initVal;
	uint8_t tmp = 0;
	
	printf("CRC_Mode: %s\n", CRC8_Table[Mode].funcName);
	
	for(uint16_t i=0;i<Len;i++){
		tmp = *(pMsg++);
		if(CRC8_Table[Mode].bits == LSB_MODE){
			_InvertU8(&tmp, &tmp);
		}
		CRCin ^= tmp;
		for(uint8_t j=0;j<8;j++){
			if(CRCin & 0x80){
				CRCin = (CRCin << 1) ^ CRC8_Table[Mode].POLY;
			}else{
				CRCin <<= 1;
			}
		}
	}
	if(CRC8_Table[Mode].bits == LSB_MODE){
		_InvertU8(&CRCin, &CRCin);
	}
	return (CRCin ^ CRC8_Table[Mode].sub);
}

測試程序如下：

uint8_t TEST_ARR[]={
	0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 
	0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 
	0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 
	0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, 
	0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, 
	0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 
	0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 
	0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, 
	0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 
	0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, 
	0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, 
	0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, 
	0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, 
	0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf, 
	0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, 
	0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff
};	

int main(void)
{
	HAL_Init();
	SystemClock_Config();
	MX_GPIO_Init();
	MX_DMA_Init();
	MX_ADC_Init();
	MX_SPI1_Init();
	MX_TIM2_Init();
	MX_USART2_UART_Init();	
	printf("==============================================\r\n");
	printf("================= stm32L0 ESL =================\r\n\r\n");
#if 1
	for(uint8_t i=0;i<8;i++){
	printf("CRC16: %02X\n\n",calc_crc16(i,TEST_ARR,256));
	}
	for(uint8_t i=0;i<4;i++){
	printf("CRC8: %02X\n\n",calc_crc8(i,TEST_ARR,256));
	}
	for(uint8_t i=0;i<2;i++){
	printf("CRC32: %02X\n\n",calc_crc32(i,TEST_ARR,256));
	}
	while(1);
#endif	
}

測試結果：