DMA介绍

DMA(Direct MemoryAccess,直接存储器访问)提供在外设与内存、存储器和存储器、外设与外设之间的高速数据传输使用。它允许不同速度的硬件装置来沟通,而不需要依赖于CPU,在这个时间中,CPU对于内存的工作来说就无法使用。

DMA的意义

  • 数据搬运的工作比较耗时间。

  • 数据搬运工作时效要求高(有数据来就要搬走) 。

  • 没啥技术含量(CPU节约出来的时间可以处理更重要的事)。

  • DMA是数据搬运工,代替CPU搬运数据,为CPU节省资源让CPU做其他操作。

DMA搬运的数据

  • 存储器:存储器包括自身的闪存(flash)或者内存(SRAM)以及外设的存储设备都可以作为访问的源或者目标。

  • 外设:外设指的是spi、usart、iic、adc 等基于APB1、APB2或AHB时钟的外设。

DMA搬运的地点

  • 存储器—>存储器(例如:复制某特别大的数据buf)

  • 存储—>外设(例:将某数据buf写入串口TDR寄存器)

  • 外设—>存储器(例如:将串口RDR寄存器写入某数据buf)

DMA通道

STM32F103C8T6有2个DMA控制器,DMA1有7个通道,DMA2有5个通道,一个通道每次只能搬运一个外设的数据,如果同时有多个外设的DMA请求,则按照通道优先级进行响应。

仲裁器

  • 仲裁器会通过DMA通道请求的优先级来启动对外设/内存的访问,也就是哪个通道的优先级最高,DMA就先响应哪个通道。

  • DMA通道优先级管理由软件优先级和硬件优先级组成:

  1. 软件优先级:每个通道的优先权可以在DMA_CCRx寄存器中设置,有4个等级:

  • 最高优先级(Very High)

  • 高优先级(High)

  • 中等优先级(Medium)

  • 低优先级(Low)

  1. 硬件优先级:如果2个请求有相同的软件优先级,则较低编号的通道比较高编号的通道有较高的优先权。

控制器

DMA1




DMA2




DMA处理

在发生一个DMA请求事件后,外设向DMA控制器发送一个请求信号。DMA控制器根据通道优先级处理请求。当DMA控制器开始访问发出DMA请求的外设时,DMA控制器立即发送给外设一个应答信号。当外设从DMA控制器得到应答信号时,立即释放它的DMA请求。一旦外设释放了这个请求,DMA控制器同时撤销应答信号。如果有更多的请求时,外设可以启动下一个周期。

DMA传输的三个操作

  1. 从外设数据寄存器或者从当前外设/存储器地址寄存器指示的存储器地址取数据,第一次传输时的开始地址是DMA_CPARx或DMA_CMARx寄存器指定的外设基地址或存储器单元。(从旧地点取数据)

  1. 存数据到外设数据寄存器或者当前外设/存储器地址寄存器指示的存储器地址,第一次传输时的开始地址是DMA_CPARx或DMA_CMARx寄存器指定的外设基地址或存储器单元。(到新地点存数据)

  1. 执行一次DMA_CNDTRx寄存器的递减操作,该寄存器包含未完成的操作数目。(操作数递减1次)

DMA传输的方式

正常模式(DMA Mode Normal)

  • 一次DMA数据传输完后,停止DMA传送,也就是只传输一次。

  • 要开始新的DMA传输,需要在关闭DMA通道的情况下,在DMA CNDTRx寄存器中重新写入传输数目。

循环传输模式(DMA Mode Circular)

  • 当传输结束时,硬件自动会将传输数据量寄存器进行重装,进行下一轮的数据传输。 也就是多次传输模式。

  • 主要用于处理循环缓冲区和连续的数据传输。

指针增量模式

外设和存储器指针在每次传输后可以自动向后递增或保持常量。当设置为增量模式时,下一个要传输的地址将是前一个地址加上增量值。

  • 源指针和目标指针都设置为增量模式




  • 源指针设置为增量模式




  • 一般设计存储器的都开启指针增量模式

DMA中断

每个DMA通道都有3个事件(DMA半传输、DMA传输完成和DMA传输错误),这3个事件都可以成为一个单独的中断请求。


中断事件

事件标志位

使能控制位

DMA半传输

HTIF

HTIE

DMA传输完成

TCIF

TCIE

DMA传输错误

TEIF

TEIE

DMA实验1(存储器 -> 存储器)

使用DMA的方式将数组A的内容复制到数组B中,搬运完之后将数组B的内容通过串口打印到屏幕,同时每隔0.5s翻转一次LED1的电平。

STM32的hal库关于DMA的函数

HAL_DMA_Start()

开启某个DMA通道的数据运输。


原型:HAL_StatusTypeDef HAL_DMA_Start(DMA_HandleTypeDef _hdma, uint32_t SrcAddress, uint32_t DstAddress, uint32_t DataLength)




参数:

DMA_HandleTypeDef _hdma:DMA通道句柄

uint32_t SrcAddress:源数据地址

DstAddress:目标数据地址

DataLength:数据长度




实例:


#define BUF_SIZE 16


uint32_t srcBuf[BUF_SIZE] = {


0x00000000,0x11111111,0x22222222,0x33333333,


0x44444444,0x55555555,0x66666666,0x77777777,


0x88888888,0x99999999,0xaaaaaaaa,0xbbbbbbbb,


0xcccccccc,0xdddddddd,0xeeeeeeee,0xffffffff


};


uint32_t desBuf[BUF_SIZE];



HAL_DMA_Start(&hdma_memtomem_dma1_channel1,(uint32_t)srcBuf,(uint32_t)desBuf,sizeof(uint32_t) _ BUF_SIZE); //开启DMA1通道1的数据传输

HAL_DMA_GET_FLAG

 

检测某个DMA通道的数据传输情况。


原型:
HAL_DMA_GET_FLAG(DMA_HandleTypeDef _hdma,__FLAG__)




参数:

DMA_HandleTypeDef *hdma:DMA通道句柄

__FLAG__:

DMA_FLAG_TCx:传输完成标志

DMA_FLAG_HTx:半传输完成标志

DMA_FLAG_TEx:传输错误标志

DMA_FLAG_GLx:全局中断标志




实例:HAL_DMA_GET_FLAG(&hdma_memtomem_dma1_channel1,DMA_FLAG_TC1) //检测DMA1通道1的数据传输是否完成,完成返回RESET

 

 

使用STM32CubeMX创建工程

 

配置SYS

 




 

 

配置RCC

 




 




 

 

配置GPIO

 

PB8配置成输出高电平

 




 

 

配置串口信息(UART1)

 




 

 

配置DMA

 

使用DMA1的通道1,传输方向为内存到内存

 




 

 

配置工程名称、工程路径

 




 

 

选择固件库

 




 

 

生成工程

 




 

 

使用MicroLIB库

 




 

 

main.c文件编写

/* 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"
 
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include <stdio.h>
 
#define BUF_SIZE 16
/* 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 */
 
//重写stdio.h文件中的prinft()里的fputc()函数
int fputc(int my_data,FILE *p)
{
    unsigned char temp = my_data;
    //改写后,使用printf()函数会将数据通过串口一发送出去
    HAL_UART_Transmit(&huart1,&temp,1,0xffff);  //0xfffff为最大超时时间
    return my_data;
}
 
//源数组
uint32_t srcBuf[BUF_SIZE] = {
    0x00000000,0x11111111,0x22222222,0x33333333,
    0x44444444,0x55555555,0x66666666,0x77777777,
    0x88888888,0x99999999,0xaaaaaaaa,0xbbbbbbbb,
    0xcccccccc,0xdddddddd,0xeeeeeeee,0xffffffff
};
 
//目标数组
uint32_t desBuf[BUF_SIZE];
 
/* USER CODE END 0 */
 
/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{
  /* USER CODE BEGIN 1 */
    int i = 0;
  /* 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_USART1_UART_Init();
  /* USER CODE BEGIN 2 */
 
    //①:开启DMA1通道1的数据传输
    HAL_DMA_Start(&hdma_memtomem_dma1_channel1,(uint32_t)srcBuf,(uint32_t)desBuf,sizeof(uint32_t) * BUF_SIZE);  //DMA1通道1的数据开始传输
    
    //②:等待DMA1通道1数据传输完成
    while(__HAL_DMA_GET_FLAG(&hdma_memtomem_dma1_channel1,DMA_FLAG_TC1) == RESET);  //等待某个通道的数据传输完成,flag标志位置位RESET
    
    //③:打印数组内容
    for(i = 0;i < BUF_SIZE;i++){
        printf("Buf[%d] = %X\r\n",i,desBuf[i]);
    }
    
  /* USER CODE END 2 */
 
  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* USER CODE END WHILE */
 
    /* USER CODE BEGIN 3 */
        
        HAL_GPIO_TogglePin(GPIOB,GPIO_PIN_8);
        HAL_Delay(500);
        
  }
  /* USER CODE END 3 */
}
 
/**
  * @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 */

DMA实验2(存储器 -> 外设:UART1)

 

使用DMA的方式将存储器的内容发送到串口1,同时每隔0.5s翻转一次LED1的电平。

 

STM32的hal库关于DMA的函数

 

HAL_UART_Transmit_DMA()

 

使用DMA将其他地方的数据搬运到串口。

 


原型:HAL_StatusTypeDef HAL_UART_Transmit_DMA(UART_HandleTypeDef _huart, uint8_t _pData, uint16_t Size)




参数:

UART_HandleTypeDef _huart:串口句柄

uint8_t _pData:传输数据地址

uint16_t Size:传输数据大小




实例:

#define BUF_SIZE 1000



unsigned char sendBuf[BUF_SIZE] = {0};



for(i = 0;i < BUF_SIZE;i++){

sendBuf[i] = ‘h’;

}



HAL_UART_Transmit_DMA(&huart1,sendBuf,BUF_SIZE); //将数据通过串口DMA发送

 

 

使用STM32CubeMX创建工程

 

配置SYS

 




 

 

配置RCC

 




 




 

 

配置GPIO

 

PB8配置成输出高电平

 




 

 

配置串口信息(UART1)

 




 

 

配置DMA

 

  • 使用DMA1的通道4,传输方向为内存到外设(串口1)

 

  • 配置成正常模式只会向串口发送一次数组内容,而配置成循环模式将不断向串口发送数组内容

 




 

 

配置工程名称、工程路径

 




 

 

选择固件库

 




 

 

生成工程

 




 

 

使用MicroLIB库

 




 

 

main.c文件编写

/* 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"
 
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
 
#define BUF_SIZE 1000
 
/* 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 */
 
//待发送数据
unsigned char sendBuf[BUF_SIZE] = {0};
 
/* USER CODE END 0 */
 
/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{
  /* USER CODE BEGIN 1 */
    int i = 0;
  /* 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_USART1_UART_Init();
  /* USER CODE BEGIN 2 */
 
    //①:准备数据
    for(i = 0;i < BUF_SIZE;i++){
        sendBuf[i] = 'h';
    }
 
    //②:将数据通过串口DMA发送
    HAL_UART_Transmit_DMA(&huart1,sendBuf,BUF_SIZE);  //将数据通过串口DMA发送
    
  /* USER CODE END 2 */
 
  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* USER CODE END WHILE */
 
    /* USER CODE BEGIN 3 */
        
        HAL_GPIO_TogglePin(GPIOB,GPIO_PIN_8);
        
        HAL_Delay(500);
        
  }
  /* USER CODE END 3 */
}
 
/**
  * @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 */

 

DMA实验3(外设:UART1 -> 存储器)

 

使用DMA的方式将串口1接收缓存寄存器的数据搬运到存储器中,再通过串口打印存储器数据,同时每隔0.5s翻转一次LED1的电平。

 

 

实现流程

 

  • 使能IDLE空闲中断,当检测到串口空闲时(串口每接收完一份数据)就会调用一次串口中断。

 

  • 将串口数据使用DMA搬运到内存。

 

  • 在串口的中断处理函数USART1_IRQHandler()中将内存的数据显示在串口中:

 

  1. 判断是否是串口空闲触发的中断,即判断IDLE标志位是否置位SET。

 

  1. 停止DMA从串口搬运数据到内存。

 

  1. 获取DMA从串口搬运的数据大小。

 

  • 将DMA从串口搬运的内存数据打印在串口。

 

  • 重新将串口数据使用DMA搬运到内存,准备下一次的重复操作。

 

 

STM32的hal库关于DMA的函数

 

HAL_UART_Receive_DMA()

 

使用DMA搬运串口数据到其他地方

 


原型:

HAL_StatusTypeDef HAL_UART_Receive_DMA(UART_HandleTypeDef _huart, uint8_t _pData, uint16_t Size)




参数:

UART_HandleTypeDef _huart:串口句柄

uint8_t *pData:传输数据地址

uint16_t Size:传输数据大小




实例:

#define BUF_SIZE 1000



uint8_t rcvBuf[BUF_SIZE] = {0};



HAL_UART_Receive_DMA(&huart1,rcvBuf,BUF_SIZE); //将串口数据通过DMA接收到内存

 

 

HAL_UART_ENABLE_IT()

 

使能某个串口标志位的中断。

 


原型:

HAL_UART_ENABLE_IT(__HANDLE__, __INTERRUPT__)




参数:

__HANDLE__:串口句柄

__INTERRUPT__:

UART_IT_CTS: CTS change interrupt

UART_IT_LBD: LIN Break detection interrupt

UART_IT_TXE: Transmit Data Register empty interrupt

UART_IT_TC: Transmission complete interrupt

UART_IT_RXNE: Receive Data register not empty interrupt

UART_IT_IDLE: 串口空闲中断

UART_IT_PE: Parity Error interrupt

UART_IT_ERR: Error interrupt(Frame error, noise error, overrun error)




实例:

HAL_UART_ENABLE_IT(&huart1,UART_IT_IDLE); //使能IDLE空闲中断

 

 

HAL_UART_GET_FLAG()

 

获取串口的某个标志位的状态

 


原型:

#define HAL_UART_GET_FLAG(HANDLE__, __FLAG__) (((__HANDLE__)->Instance->SR & (__FLAG__)) == (__FLAG__))




参数:

_HANDLE__:串口句柄

__FLAG__:

UART_FLAG_CTS: CTS Change flag (not available for UART4 and UART5)

UART_FLAG_LBD: LIN Break detection flag

UART_FLAG_TXE: Transmit data register empty flag

UART_FLAG_TC: Transmission Complete flag

UART_FLAG_RXNE: Receive data register not empty flag

UART_FLAG_IDLE: 串口空闲标志位

UART_FLAG_ORE: Overrun Error flag

UART_FLAG_NE: Noise Error flag

UART_FLAG_FE: Framing Error flag

UART_FLAG_PE: Parity Error flag




实例:

HAL_UART_GET_FLAG(&huart1,UART_FLAG_IDLE) //获取IDLE标志位的状态,如果被置位了为SET

 

 

HAL_UART_DMAStop()

 

停止DMA从串口搬运数据或者停止DMA搬运数据到串口。

 


原型:

HAL_StatusTypeDef HAL_UART_DMAStop(UART_HandleTypeDef _huart)




参数:

UART_HandleTypeDef _huart:串口句柄




实例:

HAL_UART_DMAStop(&huart1); //停止DMA从串口搬运数据

 

 

使用STM32CubeMX创建工程

 

配置SYS

 




 

 

配置RCC

 




 




 

 

配置GPIO

 

PB8配置成输出高电平

 




 

 

配置串口信息(UART1)

 




 

 

配置DMA

 

使用DMA1的通道5,传输方向为外设(串口1)到内存

 




 

 

配置工程名称、工程路径

 




 

 

选择固件库

 




 

 

生成工程

 




 

 

使用MicroLIB库

 




 

 

main.c文件编写

/* 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"
 
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#define BUF_SIZE 100
/* 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 rcvBuf[BUF_SIZE] = {0};  //接收数据缓存数组
uint8_t rcvLen = 0;  //接收一份数据的长度
 
/* 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_USART1_UART_Init();
  /* USER CODE BEGIN 2 */
 
    //使能IDLE空闲中断,当检测到串口空闲时就会调用串口中断
    __HAL_UART_ENABLE_IT(&huart1,UART_IT_IDLE);
    
    //DMA搬运串口数据到内存
    HAL_UART_Receive_DMA(&huart1,rcvBuf,BUF_SIZE);
 
  /* USER CODE END 2 */
 
  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* USER CODE END WHILE */
 
    /* USER CODE BEGIN 3 */
        
        HAL_GPIO_TogglePin(GPIOB,GPIO_PIN_8);
        HAL_Delay(500);
        
  }
  /* USER CODE END 3 */
}
 
/**
  * @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 */

stm32f1xx_it.c文件编写

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file    stm32f1xx_it.c
  * @brief   Interrupt Service Routines.
  ******************************************************************************
  * @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 "stm32f1xx_it.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
/* USER CODE END Includes */
 
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN TD */
 
/* USER CODE END TD */
 
/* 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 -----------------------------------------------*/
/* USER CODE BEGIN PFP */
 
/* USER CODE END PFP */
 
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
 
extern uint8_t rcvBuf[BUF_SIZE];  //接收数据缓存数组
extern uint8_t rcvLen;  //接收一帧数据的长度
 
/* USER CODE END 0 */
 
/* External variables --------------------------------------------------------*/
extern DMA_HandleTypeDef hdma_usart1_rx;
extern DMA_HandleTypeDef hdma_usart1_tx;
extern UART_HandleTypeDef huart1;
/* USER CODE BEGIN EV */
 
/* USER CODE END EV */
 
/******************************************************************************/
/*           Cortex-M3 Processor Interruption and Exception Handlers          */
/******************************************************************************/
/**
  * @brief This function handles Non maskable interrupt.
  */
void NMI_Handler(void)
{
  /* USER CODE BEGIN NonMaskableInt_IRQn 0 */
 
  /* USER CODE END NonMaskableInt_IRQn 0 */
  /* USER CODE BEGIN NonMaskableInt_IRQn 1 */
  while (1)
  {
  }
  /* USER CODE END NonMaskableInt_IRQn 1 */
}
 
/**
  * @brief This function handles Hard fault interrupt.
  */
void HardFault_Handler(void)
{
  /* USER CODE BEGIN HardFault_IRQn 0 */
 
  /* USER CODE END HardFault_IRQn 0 */
  while (1)
  {
    /* USER CODE BEGIN W1_HardFault_IRQn 0 */
    /* USER CODE END W1_HardFault_IRQn 0 */
  }
}
 
/**
  * @brief This function handles Memory management fault.
  */
void MemManage_Handler(void)
{
  /* USER CODE BEGIN MemoryManagement_IRQn 0 */
 
  /* USER CODE END MemoryManagement_IRQn 0 */
  while (1)
  {
    /* USER CODE BEGIN W1_MemoryManagement_IRQn 0 */
    /* USER CODE END W1_MemoryManagement_IRQn 0 */
  }
}
 
/**
  * @brief This function handles Prefetch fault, memory access fault.
  */
void BusFault_Handler(void)
{
  /* USER CODE BEGIN BusFault_IRQn 0 */
 
  /* USER CODE END BusFault_IRQn 0 */
  while (1)
  {
    /* USER CODE BEGIN W1_BusFault_IRQn 0 */
    /* USER CODE END W1_BusFault_IRQn 0 */
  }
}
 
/**
  * @brief This function handles Undefined instruction or illegal state.
  */
void UsageFault_Handler(void)
{
  /* USER CODE BEGIN UsageFault_IRQn 0 */
 
  /* USER CODE END UsageFault_IRQn 0 */
  while (1)
  {
    /* USER CODE BEGIN W1_UsageFault_IRQn 0 */
    /* USER CODE END W1_UsageFault_IRQn 0 */
  }
}
 
/**
  * @brief This function handles System service call via SWI instruction.
  */
void SVC_Handler(void)
{
  /* USER CODE BEGIN SVCall_IRQn 0 */
 
  /* USER CODE END SVCall_IRQn 0 */
  /* USER CODE BEGIN SVCall_IRQn 1 */
 
  /* USER CODE END SVCall_IRQn 1 */
}
 
/**
  * @brief This function handles Debug monitor.
  */
void DebugMon_Handler(void)
{
  /* USER CODE BEGIN DebugMonitor_IRQn 0 */
 
  /* USER CODE END DebugMonitor_IRQn 0 */
  /* USER CODE BEGIN DebugMonitor_IRQn 1 */
 
  /* USER CODE END DebugMonitor_IRQn 1 */
}
 
/**
  * @brief This function handles Pendable request for system service.
  */
void PendSV_Handler(void)
{
  /* USER CODE BEGIN PendSV_IRQn 0 */
 
  /* USER CODE END PendSV_IRQn 0 */
  /* USER CODE BEGIN PendSV_IRQn 1 */
 
  /* USER CODE END PendSV_IRQn 1 */
}
 
/**
  * @brief This function handles System tick timer.
  */
void SysTick_Handler(void)
{
  /* USER CODE BEGIN SysTick_IRQn 0 */
 
  /* USER CODE END SysTick_IRQn 0 */
  HAL_IncTick();
  /* USER CODE BEGIN SysTick_IRQn 1 */
 
  /* USER CODE END SysTick_IRQn 1 */
}
 
/******************************************************************************/
/* STM32F1xx Peripheral Interrupt Handlers                                    */
/* Add here the Interrupt Handlers for the used peripherals.                  */
/* For the available peripheral interrupt handler names,                      */
/* please refer to the startup file (startup_stm32f1xx.s).                    */
/******************************************************************************/
 
/**
  * @brief This function handles DMA1 channel4 global interrupt.
  */
void DMA1_Channel4_IRQHandler(void)
{
  /* USER CODE BEGIN DMA1_Channel4_IRQn 0 */
 
  /* USER CODE END DMA1_Channel4_IRQn 0 */
  HAL_DMA_IRQHandler(&hdma_usart1_tx);
  /* USER CODE BEGIN DMA1_Channel4_IRQn 1 */
 
  /* USER CODE END DMA1_Channel4_IRQn 1 */
}
 
/**
  * @brief This function handles DMA1 channel5 global interrupt.
  */
void DMA1_Channel5_IRQHandler(void)
{
  /* USER CODE BEGIN DMA1_Channel5_IRQn 0 */
 
  /* USER CODE END DMA1_Channel5_IRQn 0 */
  HAL_DMA_IRQHandler(&hdma_usart1_rx);
  /* USER CODE BEGIN DMA1_Channel5_IRQn 1 */
 
  /* USER CODE END DMA1_Channel5_IRQn 1 */
}
 
/**
  * @brief This function handles USART1 global interrupt.
  */
 
 
void USART1_IRQHandler(void)
{
  /* USER CODE BEGIN USART1_IRQn 0 */
  /* USER CODE END USART1_IRQn 0 */
  HAL_UART_IRQHandler(&huart1);
  /* USER CODE BEGIN USART1_IRQn 1 */
    
    //如果是串口1空闲触发的中断,IDLE标志位会置位SET
    if(__HAL_UART_GET_FLAG(&huart1,UART_FLAG_IDLE) == SET){  
        //__HAL_UART_CLEAR_FEFLAG(&huart1);  //清除帧错误标志位FE,该位会提醒当前字符是否存在帧错误    
        HAL_UART_DMAStop(&huart1);  //停止DMA从串口1中搬运数据
        uint8_t tempLen = __HAL_DMA_GET_COUNTER(&hdma_usart1_rx);  //获取DMA未搬运的数据大小    
        rcvLen = BUF_SIZE - tempLen;  //DMA当前搬运了的数据大小
        HAL_UART_Transmit(&huart1,rcvBuf,rcvLen,0xffff);        //将内存数据通过DNA发送到串口
        HAL_UART_Receive_DMA(&huart1,rcvBuf,BUF_SIZE);  //重新开始DMA搬运串口数据到内存
    }
    
  /* USER CODE END USART1_IRQn 1 */
}
 
/* USER CODE BEGIN 1 */
 
/* USER CODE END 1 */