STM32CubeMX HAL库工程串口DMA定长CRC校验接收

1.先配置好工程

2.修改usart.c添加crc8代码

• 在/* USER CODE BEGIN 0 */和/* USER CODE END 0 */之间添加如下代码

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

• 在/* USER CODE BEGIN 1 */和/* USER CODE END 1 */之间添加如下代码

unsigned char cal_crc_table(unsigned char *ptr, unsigned char len) 
{
    unsigned char  crc = 0x00;
 
    while (len--)
    {
        crc = crc_table[crc ^ *ptr++];
    }
    return (crc);
}

3.修改usart.h添加数组和函数声明代码

• 在/* USER CODE BEGIN Prototypes */和/* USER CODE END Prototypes */之间添加以下声明

unsigned char cal_crc_table(unsigned char *ptr, unsigned char len);

4.使能串口1 DMA接收

• 根据串口定义接收数组长度

/* USER CODE BEGIN PV */
uint8_t u1_rx_buf[5];
/* USER CODE END PV */

• 开始接收

HAL_UART_Receive_DMA(&huart1, u1_rx_buf, 5);

5.重写串口 DMA接收回调函数

void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
	if(huart->Instance == USART1)
	{
		if(cal_crc_table(u1_rx_buf, 4) == u1_rx_buf[4])	//如果crc8校验成功，则对数据进行处理
		{
			printf("CRC OK.\r\n");
			printf("u1_rx_buf = %d %d %d %d.\r\n",u1_rx_buf[0],u1_rx_buf[1],u1_rx_buf[2],u1_rx_buf[3]);
		}else
		{
			printf("CRC error.\r\n");
			//接收到错误后重启DMA
			tx_delay_ms(3);//此处需要延时一下，不然会发生错误
			HAL_UART_DMAStop(&huart1);
			HAL_UART_Receive_DMA(&huart1, u1_rx_buf, 5);
		}
	}
}