STM32串口中断接收实验（HAL库）

工具：

单片机：STM32L053R8T6（NUCLEO板）

STM32cube

简介：STM32与上位机之间用通信协议（自己定义）进行串口通信。怎么判断上位机发过来的指令是正确的，而不是一串乱码？怎么从正确的指令中提取出想要的命令代号，从而实现想要的功能？

方法：读取上位机发来的命令，逐位判断命令的包头和包尾，如果能对应上，则这串指令是正确的，然后从指令中提取想要的数据和命令等。举个栗子：通信协议是自己定义的，不是modbus协议等。。如F0 5A 15 15 25 16 09 02 12 14 FF A5 F0（都是16进制），F0 5A是包头，A5 F0是包尾，黑色15是命令代号，中间蓝色是我想发的数据，橙色FF是校验位。只要包头包尾校验正确，基本这串指令不会有问题。

UART中断函数：

void HAL_UART_RxCpltCallback(UART_HandleTypeDef *UartHandle)
{
	unsigned char temp;
	receive0[receive0_tail]=aRxBuffer;
	temp=receive0[receive0_tail];
	if((temp == 0xf0)&&(head0_flag == 0))
	{
	  head0_flag=1;
		receive0_len=1;
	}
	else if(head0_flag == 1)
	{
	  if(temp==0x5a)
		{
		  head0_flag = 2;
			receive0_len++;
		}
		else
		{
		  head0_flag = 0;
		}
	}
	else if ((temp==0xa5)&&(head0_flag == 2))
	{
	  head0_flag = 3;
		receive0_len++;
	}
  else if (head0_flag == 3)
	{
	  receive0_len++;
		if(temp==0xf0)
		{
			head0_flag = 0;
			HW0_COM=1;
		}
		else
		{
		  head0_flag = 2;
		}
	}
	else 
	{
		receive0_len++;
	  if(receive0_len>70)
		{
		  receive0_len=0;
			head0_flag = 0;
		}
	}
  receive0_tail++;
	if(receive0_tail>=128)
	{
	  receive0_tail=0;
	}
	HAL_UART_Receive_IT(&huart1,&aRxBuffer,1);
}

 main函数：其中main函数是测试程序，把串口助手发来的数据再上传回去，目的是看发送和读取是否一致。

int main(void)
{
   uint8_t txbuf[100];
  /* USER CODE BEGIN 1 */
    
  /* USER CODE END 1 */

  /* MCU Configuration----------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();

  /* USER CODE BEGIN Init */
   
  /* USER CODE END Init */

  /* Configure the system clock */
  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_USART1_UART_Init();

  /* USER CODE BEGIN 2 */
	command=0;
  receive0_tail=0;
	receive0_len=0;
	HW0_COM=0;
  /* USER CODE END 2 */

  memcpy(txbuf,"这是一个串口中断接收回显实验\n",100);
  HAL_UART_Transmit(&huart1,txbuf,strlen((char *)txbuf),1000);
	HAL_UART_Receive_IT(&huart1,&aRxBuffer,1);
  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
  /* USER CODE END WHILE */
  /* USER CODE BEGIN 3 */
    command=ReadComm();
		switch(command)
		{
			case 0x15:
			{
//				memcpy(txbuf,"这是0x15\n",100);
//				HAL_UART_Transmit(&huart1,txbuf,strlen((char *)txbuf),1000);
				HAL_UART_Transmit(&huart1,receive0,strlen((char *)receive0),1000);
				HW0_COM=0;
				receive0_len=0;
				head0_flag = 0;
				receive0_tail=0;
				break;
			}
			case 0x1a:
			{
//				memcpy(txbuf,"这是0x1a\n",100);
//				HAL_UART_Transmit(&huart1,txbuf,strlen((char *)txbuf),1000);
				HAL_UART_Transmit(&huart1,receive0,strlen((char *)receive0),1000);
				HW0_COM=0;
				receive0_len=0;
				head0_flag = 0;
				receive0_tail=0;
				break;
			}
			default:
				break;
		}
     	command=0;
  }
	
  /* USER CODE END 3 */
}

详细工程：https://download.csdn.net/download/geekjin/10657761