stm32hal串口dma空闲中断

在使用STM32HAL库时，可以通过以下步骤实现串口DMA空闲中断：

1. 配置串口DMA传输，使其使用循环模式和使用空闲中断。

/* Configure the DMA handler for Transmission process */
hdma_tx.Instance                 = USARTx_TX_DMA_STREAM;

hdma_tx.Init.Channel             = USARTx_TX_DMA_CHANNEL;
hdma_tx.Init.Direction           = DMA_MEMORY_TO_PERIPH;
hdma_tx.Init.PeriphInc           = DMA_PINC_DISABLE;
hdma_tx.Init.MemInc              = DMA_MINC_ENABLE;
hdma_tx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
hdma_tx.Init.MemDataAlignment    = DMA_MDATAALIGN_BYTE;
hdma_tx.Init.Mode                = DMA_NORMAL;
hdma_tx.Init.Priority            = DMA_PRIORITY_LOW;
hdma_tx.Init.FIFOMode            = DMA_FIFOMODE_DISABLE;
hdma_tx.Init.FIFOThreshold       = DMA_FIFO_THRESHOLD_FULL;
hdma_tx.Init.MemBurst            = DMA_MBURST_INC4;
hdma_tx.Init.PeriphBurst         = DMA_PBURST_INC4;

/* Initialize DMA handle */
if(HAL_DMA_Init(&hdma_tx) != HAL_OK)
{
  Error_Handler();
}

/* Associate the initialized DMA handle to the the UART handle */
__HAL_LINKDMA(huart, hdmatx, hdma_tx);

/* Configure the DMA handler for reception process */
hdma_rx.Instance                 = USARTx_RX_DMA_STREAM;
hdma_rx.Init.Channel             = USARTx_RX_DMA_CHANNEL;
hdma_rx.Init.Direction           = DMA_PERIPH_TO_MEMORY;
hdma_rx.Init.PeriphInc           = DMA_PINC_DISABLE;
hdma_rx.Init.MemInc              = DMA_MINC_ENABLE;
hdma_rx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
hdma_rx.Init.MemDataAlignment    = DMA_MDATAALIGN_BYTE;
hdma_rx.Init.Mode                = DMA_CIRCULAR;
hdma_rx.Init.Priority            = DMA_PRIORITY_HIGH;
hdma_rx.Init.FIFOMode            = DMA_FIFOMODE_DISABLE;
hdma_rx.Init.FIFOThreshold       = DMA_FIFO_THRESHOLD_FULL;
hdma_rx.Init.MemBurst            = DMA_MBURST_INC4;
hdma_rx.Init.PeriphBurst         = DMA_PBURST_INC4;

/* Initialize DMA handle */
if(HAL_DMA_Init(&hdma_rx) != HAL_OK)
{
  Error_Handler();
}

/* Associate the initialized DMA handle to the the UART handle */
__HAL_LINKDMA(huart, hdmarx, hdma_rx);

/* Configure the DMA handler callbacks */
HAL_DMA_RegisterCallback(&hdma_tx, HAL_DMA_XFER_CPLT_CB_ID, DMA_TxCpltCallback);
HAL_DMA_RegisterCallback(&hdma_rx, HAL_DMA_XFER_CPLT_CB_ID, DMA_RxCpltCallback);
HAL_DMA_RegisterCallback(&hdma_rx, HAL_DMA_XFER_ERROR_CB_ID, DMA_RxErrorCallback);

/* Configure DMA transfer interrupts */
__HAL_DMA_ENABLE_IT(&hdma_rx, DMA_IT_TC);
__HAL_DMA_DISABLE_IT(&hdma_rx, DMA_IT_HT);
__HAL_DMA_DISABLE_IT(&hdma_rx, DMA_IT_FE);
__HAL_DMA_DISABLE_IT(&hdma_rx, DMA_IT_TE);

2. 实现DMA传输完成回调函数。

void HAL_UART_TxCpltCallback(UART_HandleTypeDef *huart)
{
  /* Transmission complete callback */
}

void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
  /* Reception complete callback */
}

void HAL_UART_ErrorCallback(UART_HandleTypeDef *huart)
{
  /* UART error callback */
}

3. 实现DMA空闲中断回调函数。

void HAL_UART_IDLE_IRQHandler(UART_HandleTypeDef *huart)
{
  /* Disable DMA transfer on reception */
  hdma_rx.Instance->CR &= ~DMA_SxCR_EN;

  /* Clear IDLE flag */
  __HAL_UART_CLEAR_IDLEFLAG(huart);

  /* Call user callback */
  HAL_UART_RxCpltCallback(huart);

  /* Enable DMA transfer on reception */
  hdma_rx.Instance->CR |= DMA_SxCR_EN;
}

4. 配置空闲中断使能。

/* Enable the UART Idle Interrupt */
__HAL_UART_ENABLE_IT(&huart, UART_IT_IDLE);

通过以上步骤，就可以实现串口DMA空闲中断。