使用STM32CubeMX+DMA+空闲中断实现串口接收和发送数据（STM32G070CBT6）

1.STM32CubeMX配置

（1）配置SYS

（2）配置RCC

（3）配置串口，此处我用的是串口4，其他串口也是一样的

（4）配置DMA，将串口4的TX和RX添加到DMA中

（5）到这里就全部配置好了，生成代码即可

2.代码编写

（1）先定义一个数组用于存储串口接收的数据。

uint8_t buffer[10]={0};

（2）打开DMA接收和开启空闲中断

HAL_UART_Receive_DMA(&huart4,buffer,5);      //打开串口DMA接收，此处是接收5个数据，存入到buffer这个数组中
__HAL_UART_ENABLE_IT(&huart4,UART_IT_IDLE);   //开启空闲中断，进入空闲就打开中断

（3）在串口中断函数中编写相关功能代码

注意：__HAL_DMA_GET_COUNTER函数获取DMA中未传输的数据个数，所以要计算DMA接收到了多少个数，需要用定义接收的数组大小减去该函数返回值。

void USART3_4_IRQHandler(void)
{/* USER CODE BEGIN USART3_4_IRQn 0 */if(__HAL_UART_GET_FLAG(&huart4,UART_FLAG_IDLE) != RESET) //进入空闲状态触发当前中断{__HAL_UART_CLEAR_IDLEFLAG(&huart4); //清除空闲中断标志位HAL_UART_DMAStop(&huart4);  //停止DMA，进入一次空闲中断表示DMA传输完成uint8_t len = 10 - __HAL_DMA_GET_COUNTER(huart4.hdmarx); //实际上接收到的数据HAL_UART_Transmit_DMA(&huart4,buffer,len); //发送数据到串口HAL_UART_Receive_DMA(&huart4,buffer, 5);    //打开DMA再一次接收数据}/* USER CODE END USART3_4_IRQn 0 */HAL_UART_IRQHandler(&huart4);/* USER CODE BEGIN USART3_4_IRQn 1 *//* USER CODE END USART3_4_IRQn 1 */
}

（4）贴出main.c全部代码

/* USER CODE BEGIN Header */
/********************************************************************************* @file           : main.c* @brief          : Main program body******************************************************************************* @attention** Copyright (c) 2025 STMicroelectronics.* All rights reserved.** This software is licensed under terms that can be found in the LICENSE file* in the root directory of this software component.* If no LICENSE file comes with this software, it is provided AS-IS.********************************************************************************/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "dma.h"
#include "usart.h"
#include "gpio.h"/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes *//* USER CODE END Includes *//* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD *//* USER CODE END PTD *//* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD *//* USER CODE END PD *//* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM *//* USER CODE END PM *//* Private variables ---------------------------------------------------------*//* USER CODE BEGIN PV *//* USER CODE END PV *//* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP *//* USER CODE END PFP *//* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
uint8_t buffer[10]={0};/*** @brief This function handles USART3 and USART4 interrupts.*/
void USART3_4_IRQHandler(void)
{/* USER CODE BEGIN USART3_4_IRQn 0 */if(__HAL_UART_GET_FLAG(&huart4,UART_FLAG_IDLE) != RESET) //进入空闲状态触发当前中断{__HAL_UART_CLEAR_IDLEFLAG(&huart4); //清除空闲中断标志位HAL_UART_DMAStop(&huart4);  //停止DMA，进入一次空闲中断表示DMA传输完成uint8_t len = 10 - __HAL_DMA_GET_COUNTER(huart4.hdmarx); //实际上接收到的数据HAL_UART_Transmit_DMA(&huart4,buffer,len); //发送数据到串口HAL_UART_Receive_DMA(&huart4,buffer, 5);    //打开DMA再一次接收数据}/* USER CODE END USART3_4_IRQn 0 */HAL_UART_IRQHandler(&huart4);/* USER CODE BEGIN USART3_4_IRQn 1 *//* USER CODE END USART3_4_IRQn 1 */
}/* USER CODE END 0 *//*** @brief  The application entry point.* @retval int*/
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_USART4_UART_Init();/* USER CODE BEGIN 2 */HAL_UART_Receive_DMA(&huart4,buffer,5);      //打开串口DMA接收，此处是接收5个数据，存入到buffer这个数组中__HAL_UART_ENABLE_IT(&huart4,UART_IT_IDLE);   //开启空闲中断，进入空闲就打开中断/* USER CODE END 2 *//* Infinite loop *//* USER CODE BEGIN WHILE */while (1){/* USER CODE END WHILE *//* USER CODE BEGIN 3 */}/* USER CODE END 3 */
}/*** @brief System Clock Configuration* @retval None*/
void SystemClock_Config(void)
{RCC_OscInitTypeDef RCC_OscInitStruct = {0};RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};/** Configure the main internal regulator output voltage*/HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1);/** Initializes the RCC Oscillators according to the specified parameters* in the RCC_OscInitTypeDef structure.*/RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;RCC_OscInitStruct.HSIState = RCC_HSI_ON;RCC_OscInitStruct.HSIDiv = RCC_HSI_DIV1;RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK){Error_Handler();}/** Initializes the CPU, AHB and APB buses clocks*/RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK|RCC_CLOCKTYPE_PCLK1;RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK){Error_Handler();}
}/* USER CODE BEGIN 4 *//* USER CODE END 4 *//*** @brief  This function is executed in case of error occurrence.* @retval None*/
void Error_Handler(void)
{/* USER CODE BEGIN Error_Handler_Debug *//* User can add his own implementation to report the HAL error return state */__disable_irq();while (1){}/* USER CODE END Error_Handler_Debug */
}#ifdef  USE_FULL_ASSERT
/*** @brief  Reports the name of the source file and the source line number*         where the assert_param error has occurred.* @param  file: pointer to the source file name* @param  line: assert_param error line source number* @retval None*/
void assert_failed(uint8_t *file, uint32_t line)
{/* USER CODE BEGIN 6 *//* User can add his own implementation to report the file name and line number,ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) *//* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */

3.实现效果

串口发送什么数据就接收到什么数据。