uint16_t uart3_rx_buffer[USART3_RXBUF_SIZE]; //串口接收数据缓存数组
UART3Ctl UART3ctl;
/
USER CODE END 0 /
UART_HandleTypeDef huart3;
DMA_HandleTypeDef hdma_usart3_rx;
DMA_HandleTypeDef hdma_usart3_tx;
/ USART3 init function /
void MX_USART3_UART_Init(void)
{
/ USER CODE BEGIN USART3_Init 0 /
/ USER CODE END USART3_Init 0 /
/ USER CODE BEGIN USART3_Init 1 /
/ USER CODE END USART3_Init 1 /
huart3.Instance = USART3;
huart3.Init.BaudRate = 115200;
huart3.Init.WordLength = UART_WORDLENGTH_9B;
huart3.Init.StopBits = UART_STOPBITS_1;
huart3.Init.Parity = UART_PARITY_NONE;
huart3.Init.Mode = UART_MODE_TX_RX;
huart3.Init.HwFlowCtl = UART_HWCONTROL_NONE;
huart3.Init.OverSampling = UART_OVERSAMPLING_16;
if (HAL_MultiProcessor_Init(&huart3, 12, UART_WAKEUPMETHOD_ADDRESSMARK) != HAL_OK)
{
Error_Handler();}
/ USER CODE BEGIN USART3_Init 2 /
/ USER CODE END USART3_Init 2 /
}
void HAL_UART_MspInit(UART_HandleTypeDef* uartHandle)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
if(uartHandle->Instance==USART3)
{
/ USER CODE BEGIN USART3_MspInit 0 /
/ USER CODE END USART3_MspInit 0 /
/ USART3 clock enable /
__HAL_RCC_USART3_CLK_ENABLE();
__HAL_RCC_GPIOD_CLK_ENABLE();
/**USART3 GPIO Configuration
PD8 ------> USART3_TX
PD9 ------> USART3_RX
*/
GPIO_InitStruct.Pin = GPIO_PIN_8;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF7_USART3;
HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);
GPIO_InitStruct.Pin = GPIO_PIN_9;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_PULLUP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF7_USART3;
HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);
/ USART3 DMA Init /
/ USART3_RX Init /
hdma_usart3_rx.Instance = DMA1_Stream1;
hdma_usart3_rx.Init.Channel = DMA_CHANNEL_4;
hdma_usart3_rx.Init.Direction = DMA_PERIPH_TO_MEMORY;
hdma_usart3_rx.Init.PeriphInc = DMA_PINC_DISABLE;
hdma_usart3_rx.Init.MemInc = DMA_MINC_ENABLE;
hdma_usart3_rx.Init.PeriphDataAlignment = DMA_PDATAALIGN_HALFWORD;
hdma_usart3_rx.Init.MemDataAlignment = DMA_MDATAALIGN_HALFWORD;
hdma_usart3_rx.Init.Mode = DMA_NORMAL;
hdma_usart3_rx.Init.Priority = DMA_PRIORITY_LOW;
hdma_usart3_rx.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
if (HAL_DMA_Init(&hdma_usart3_rx) != HAL_OK)
{
Error_Handler();
}
__HAL_LINKDMA(uartHandle,hdmarx,hdma_usart3_rx);
/ USART3_TX Init /
hdma_usart3_tx.Instance = DMA1_Stream3;
hdma_usart3_tx.Init.Channel = DMA_CHANNEL_4;
hdma_usart3_tx.Init.Direction = DMA_MEMORY_TO_PERIPH;
hdma_usart3_tx.Init.PeriphInc = DMA_PINC_DISABLE;
hdma_usart3_tx.Init.MemInc = DMA_MINC_ENABLE;
hdma_usart3_tx.Init.PeriphDataAlignment = DMA_PDATAALIGN_HALFWORD;
hdma_usart3_tx.Init.MemDataAlignment = DMA_MDATAALIGN_HALFWORD;
hdma_usart3_tx.Init.Mode = DMA_NORMAL;
hdma_usart3_tx.Init.Priority = DMA_PRIORITY_LOW;
hdma_usart3_tx.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
if (HAL_DMA_Init(&hdma_usart3_tx) != HAL_OK)
{
Error_Handler();
}
__HAL_LINKDMA(uartHandle,hdmatx,hdma_usart3_tx);
/ USART3 interrupt Init /
HAL_NVIC_SetPriority(USART3_IRQn, 0, 0);
HAL_NVIC_EnableIRQ(USART3_IRQn);/ USER CODE BEGIN USART3_MspInit 1 /
/ USER CODE END USART3_MspInit 1 /
}
}
在主程序中开启DMA接收和空闲线中断：
int main(void)
{
/ 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_DMA_Init();
MX_USART3_UART_Init();
/ USER CODE BEGIN 2 /
// 启动DMA接收
HAL_UART_Receive_DMA(&huart3, (uint8_t*)uart3_rx_buffer, USART3_RXBUF_SIZE);
// 启用空闲中断
__HAL_UART_ENABLE_IT(&huart3, UART_IT_IDLE);
/ USER CODE END 2 /
/ Infinite loop /
/ USER CODE BEGIN WHILE /
while (1)
{
/ USER CODE END WHILE /
/ USER CODE BEGIN 3 /}
/ USER CODE END 3 /
}
中断处理函数
/**
- @brief This function handles USART3 global interrupt.
*/
void USART3_IRQHandler(void)
{
/ USER CODE BEGIN USART3_IRQn 0 /
if(__HAL_UART_GET_FLAG(&huart3 , UART_FLAG_IDLE) != RESET)//判断空闲中断
{
HAL_UART_DMAStop(&huart3); // 停止DMA接收
UART3ctl.USART3_recv_flag = 1;//串口接收到数据
UART3ctl.USART3_len = USART3_RXBUF_SIZE - __HAL_DMA_GET_COUNTER(&hdma_usart3_rx); //计算接收到的数据长度
memcpy(UART3ctl.USART3_rx_buffer,uart3_rx_buffer,UART3ctl.USART3_len);
memset(uart3_rx_buffer,0,UART3ctl.USART3_len);
__HAL_UART_CLEAR_IDLEFLAG(&huart3);//清除中断
//HAL_UART_Receive_DMA(&huart1,rx_buffer,BUFFER_SIZE);USART3_DIR_TX; //485发送
HAL_Delay(1);}
/ USER CODE END USART3_IRQn 0 /
HAL_UART_IRQHandler(&huart3);
/ USER CODE BEGIN USART3_IRQn 1 /
/ USER CODE END USART3_IRQn 1 /
}
