STM32中断与DMA方式下的串口通信教程-优快云博客

本文链接：https://blog.youkuaiyun.com/2201_75357199/article/details/134129060

文章目录

一、中断方式

1、建立工程

新建工程可参考：嵌入式作业八（使用Cube实现流水灯，并采用中断控制流水灯亮灭）-优快云博客

2、代码编写

在main.c文件中添加代码：

头文件：

#include "stdio.h"
#include "string.h"

添加变量：

uint8_t RxBuffer[LENGTH]; //字符缓冲区，LENGTH定义为4
uint8_t RxFlag = 0;//是否接受到stop
uint8_t ch;//额外字符't'的缓冲区
uint8_t flag = 1;//是否需要继续接收额外字符

while循环：

while (1)
  {
    /* USER CODE END WHILE */
	  if(RxFlag == 0){
		  HAL_UART_Transmit(&huart1,(uint8_t*)"hello windows!\r\n",16,0xffff);
		  HAL_Delay(1000);
	  }
    /* USER CODE BEGIN 3 */
  }

中断接收回调函数：

void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart){
	if(huart->Instance == USART1&&strcmp((char *)RxBuffer,"stop")==0){
		RxFlag = 1;
		HAL_UART_Receive_IT(huart, (uint8_t*)&RxBuffer, LENGTH);
	}else if(huart->Instance == USART1&&strcmp((char *)RxBuffer,"star")==0&&flag==1){
		flag = 0;
		HAL_UART_Receive_IT(huart, (uint8_t*)&ch, 1);
	}
	if(huart->Instance == USART1 && ch == 't' && flag == 0){
		RxFlag = 0;
		flag = 1;
		ch = '0';
		HAL_UART_Receive_IT(huart, (uint8_t*)&RxBuffer, LENGTH);
	}
}

3、运行效果

二、DMA方式

1、建立工程

使用STM32CubeMX，选择芯片stm32f103c8

配置RCC

设置串口USART1

添加两个通道 USART1_RX/USART_TX

NVIC Settings 一栏使能接收中断

DMA设置

时钟源设置

项目命名:

2、代码编写

主要用到的函数：
HAL_UARTEx_ReceiveToIdle_DMA(UART_HandleTypeDef *huart, uint8_t *pData, uint16_t Size)

HAL_UARTEx_ReceiveToIdle_DMA(UART_HandleTypeDef *huart, uint8_t *pData, uint16_t Size)
/*
@parameter1：串口句柄
@parameter2：目标缓存区
@parameter3：接收长度，这个接收长度一般设置大于我们所要的不定长数据长度
@note：此函数实现了：设置空闲中断模式、调用UART_Start_Receive_DMA函数、空闲中断使能
*/

HAL_UARTEx_RxEventCallback(UART_HandleTypeDef *huart, uint16_t Size)

HAL_UARTEx_RxEventCallback(UART_HandleTypeDef *huart, uint16_t Size)
/*
@note：空闲中断回调函数
*/

main.c代码：

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2023 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"
#include <stdio.h>
#include <string.h>
//#include "stm32f1xx_hal.c"

extern DMA_HandleTypeDef hdma_usart1_tx;

/* 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 */

/* USER CODE END 0 */


uint8_t order[5]="";//下位机接收的start 和stop命令
//uint8_t *order=""；//用这个会报错，因为strcmp函数
uint8_t *sendData ="hello windows!\n";
uint8_t flag=1;//标志 0:停止发送 1.开始发送

int main(void)
{

  HAL_Init();

  SystemClock_Config();
  MX_GPIO_Init();
  MX_DMA_Init();
  MX_USART1_UART_Init();
	
	
	//接收命令的函数，接收后产生空闲中断进入中断服务函数HAL_UARTEx_RxEventCallback
  HAL_UARTEx_ReceiveToIdle_DMA(&huart1,order,5);

	
  while (1)
  {
		 if (flag)
        {
            HAL_UART_Transmit_DMA(&huart1, sendData, strlen(sendData)); //以DMA模式给上位机发数据
        }
        HAL_Delay(1000);
  }

}


//关于串口空闲中断的回调函数
void 	HAL_UARTEx_RxEventCallback(UART_HandleTypeDef *huart, uint16_t Size)
{
	if(huart==&huart1)
	{
		HAL_UART_Transmit_DMA(&huart1, order, strlen(order));//下位机接收命令
	}
	
	if(!strcmp(order, "start"))
	{
		flag = 1;
	}
	
	if(!strcmp(order, "stop"))
	{
		flag = 0;
	}
	
	//继续接收命令 重新设置中断
	HAL_UARTEx_ReceiveToIdle_DMA(&huart1, order, strlen(order));
	
}

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
  RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9;
  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_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != 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 */