STM32CubeMX：UART操作

UART共有三种操作方式，轮询方式、中断方式以及DMA方式。

芯片：STM32F103C8T6

应用管脚：

输出：PA0、PA1

USART1

配置界面

添加中断配置

添加DMA配置

代码应用

1.实现printf函数

/* USER CODE BEGIN 0 */

#ifdef __GNUC__

/* With GCC/RAISONANCE, small printf (option LD Linker->Libraries->Small printf

   set to 'Yes') calls __io_putchar() */

#define PUTCHAR_PROTOTYPE int __io_putchar(int ch)

#else

#define PUTCHAR_PROTOTYPE int fputc(int ch, FILE *f)

#endif /* __GNUC__ */

/* USER CODE END 0 */

/* USER CODE BEGIN 4 */

/**

  * @brief  Retargets the C library printf function to the USART.

  * @param  None

  * @retval None

  */

PUTCHAR_PROTOTYPE

{

  /* Place your implementation of fputc here */

  /* e.g. write a character to the USART1 and Loop until the end of transmission */

  HAL_UART_Transmit(&huart1, (uint8_t *)&ch, 1, 0xFFFF);

  return ch;

}

/* USER CODE END 4 */

2.轮询方式发送与接收

发送数据

uint8_t senddata[20]="This use Transmit.rn";  
if(HAL_UART_Transmit(&huart1,senddata,sizeof(senddata),0xFFFF) != HAL_OK)
  {
    /* Transfer error in reception process */
    Error_Handler();
  }
轮询接收采用阻塞式超时接收模式

  uint8_t huart1_RxBuffer[20];
  HAL_UART_Receive(&huart1, huart1_RxBuffer, 20,0x10);
3.中断方式发送与接收
增加接收中断回调函数

/* USER CODE BEGIN 4 */
/**
  * @brief  Rx Transfer completed callbacks.
  * @param  huart: Pointer to a UART_HandleTypeDef structure that contains
  *                the configuration information for the specified UART module.
  * @retval None
  */
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
	if(huart==&huart1)
	{
		Rx_flag=1;
		HAL_GPIO_WritePin(GPIOA,GPIO_PIN_0,(GPIO_PinState)!HAL_GPIO_ReadPin(GPIOA,GPIO_PIN_0));
		
//		if(HAL_UART_Receive_IT(&huart1, (uint8_t *)huart1_RxBuffer, Rx_size) != HAL_OK)
//		{
//			/* Transfer error in reception process */
//			Error_Handler();
//		}
	}
}
 
/* USER CODE END 4 */
发送数据
uint8_t senddata_IT[23]="This use Transmit IT.rn";	
if(HAL_UART_Transmit_IT(&huart1,senddata_IT, sizeof(senddata_IT)) != HAL_OK)
	{
		/* Transfer error in reception process */
		Error_Handler();
	}
接收数据，调用此函数后，接收中断可执行一次。
uint8_t huart1_RxBuffer[20];	
if(HAL_UART_Transmit_DMA(&huart1,senddata_DMA, sizeof(senddata_DMA))!= HAL_OK)
	{
		Error_Handler();
	}

if(HAL_UART_Receive_IT(&huart1, (uint8_t *)huart1_RxBuffer, Rx_size) != HAL_OK) {/* Transfer error in reception process */ Error_Handler(); }
3.DMA方式发送与接收
增加接收中断回调函数（与中断方式相同）

发送数据

uint8_t senddata_DMA[24]="This use Transmit DMA.rn";
	if(HAL_UART_Receive_DMA(&huart1, (uint8_t *)huart1_RxBuffer, Rx_size) != HAL_OK)
  {
    /* Transfer error in reception process */
    Error_Handler();
  }

接收数据（特征与中断方式相同）
	if(HAL_UART_Receive_DMA(&huart1, (uint8_t *)huart1_RxBuffer, Rx_size) != HAL_OK)
  {
    /* Transfer error in reception process */
    Error_Handler();
  }