代码收藏家技术教程 2024-06-09

基于STM32 HAL库实现HC-SR04超声波测距模块

文章目录

一·、HC-SR04模块介绍

二、创建工程

1.选择芯片

2.配置RCC、SY![在这里插入图片描述](https://i3.wp.com/img-blog.csdnimg.cn/direct/9d2a5b883f0e409eabb804e6da861277.png)

3.配置串口1

4.配置定时器

5.配置GPIO

三、Keil代码

1.勾选Use MicroLIB

2.创建SR04.c和SR04.h文件

3.其他代码

四、效果

五、参考资料：

一·、HC-SR04模块介绍

超声波是振动频率高于20kHz的机械波。它具有频率高、波长短、绕射现象小、方向性好、能够成为射线而定向传播等特点。HC-SRO4是一款尺寸完全兼容老版本，增加UART和IIC功能的开放式超声波测距模块,默认条件下,软件与硬件完全兼容老版本HC-SRO4;可以通过电阻设置成UART或IIC模式。2CM盲区,4.5M典型最远测距，2.2mA作电流。采用升级解调芯片RCWL-9206,带UART与IIC功能MCU:使其外围更加简洁,工作电压更宽(3-5.5V),接口功能更多。

模块参数:
①专业解调测距芯片RCWL-9206
②支持GPIO,UART与IIC三种模式接口
③2.2mA工作电流
④2cm最小盲区
⑤2cm-450cm的超宽测量范围
⑥工作温度:-10°C-70°c
⑦3V-5.5V宽电压供电

注：0~40℃声速误差7%左右，实际应用时需要考虑温度影响

实验步骤

1.配置GPIO引脚结构体(Trig,Echo)
2.配置定时器结构体
3.配置定时器中断结构体
4.开启时钟（定时器、GPIO）
5.Trig引脚输出高电平(10us以上)，然后关闭
6.等待Echo引脚输出高电平开始，定时器打开->开启计数器计数
7.等待Echo引脚输出高电平结束，定时器关闭->停止计数器计数

二、创建工程

1.选择芯片

打开STM32CubuMax,新建一个项目，选择芯片

2.配置RCC、SY

S、时钟树

rcc

sys

时钟树

3.配置串口1

4.配置定时器

5.配置GPIO

完成后生成keil工程

三、Keil代码

1.勾选Use MicroLIB

2.创建SR04.c和SR04.h文件

SR04.c

#include "SR04.h"
 
float distant;      //测量距离
uint32_t measure_Buf[3] = {0};   //存放定时器计数值的数组
uint8_t  measure_Cnt = 0;    //状态标志位
uint32_t high_time;   //超声波模块返回的高电平时间
 
 
//===============================================读取距离
void SR04_GetData(void)
{
switch (measure_Cnt){
	case 0:
         TRIG_H;
         delay_us(30);
         TRIG_L;
    
		measure_Cnt++;
		__HAL_TIM_SET_CAPTUREPOLARITY(&htim2, TIM_CHANNEL_1, TIM_INPUTCHANNELPOLARITY_RISING);
		HAL_TIM_IC_Start_IT(&htim2, TIM_CHANNEL_1);	//启动输入捕获       或者: __HAL_TIM_ENABLE(&htim5);                                                                                    		
        break;
	case 3:
		high_time = measure_Buf[1]- measure_Buf[0];    //高电平时间
         printf("\r\n----高电平时间-%d-us----\r\n",high_time);							
		distant=(high_time*0.034)/2;  //单位cm
        printf("\r\n-检测距离为-%.2f-cm-\r\n",distant);          
		measure_Cnt = 0;  //清空标志位
        TIM2->CNT=0;     //清空计时器计数
		break;
				
	}
}
 
 
//===============================================us延时函数
    void delay_us(uint32_t us)//主频72M
{
    uint32_t delay = (HAL_RCC_GetHCLKFreq() / 4000000 * us);
    while (delay--)
	{
		;
	}
}
 
//===============================================中断回调函数
void HAL_TIM_IC_CaptureCallback(TIM_HandleTypeDef *htim)//
{
	
	if(TIM2 == htim->Instance)// 判断触发的中断的定时器为TIM2
	{
		switch(measure_Cnt){
			case 1:
				measure_Buf[0] = HAL_TIM_ReadCapturedValue(&htim2,TIM_CHANNEL_1);//获取当前的捕获值.
				__HAL_TIM_SET_CAPTUREPOLARITY(&htim2,TIM_CHANNEL_1,TIM_ICPOLARITY_FALLING);  //设置为下降沿捕获
				measure_Cnt++;                                            
				break;              
			case 2:
				measure_Buf[1] = HAL_TIM_ReadCapturedValue(&htim2,TIM_CHANNEL_1);//获取当前的捕获值.
				HAL_TIM_IC_Stop_IT(&htim2,TIM_CHANNEL_1); //停止捕获   或者: __HAL_TIM_DISABLE(&htim5);
				measure_Cnt++;  
                         
		}
	
	}
	
}

SR04.h

#ifndef __SR04_H
#define __SR04_H
#include "main.h"
#include "tim.h"
#include "stdio.h"
 
#define TRIG_H  HAL_GPIO_WritePin(Trig_GPIO_Port,Trig_Pin,GPIO_PIN_SET)
#define TRIG_L  HAL_GPIO_WritePin(Trig_GPIO_Port,Trig_Pin,GPIO_PIN_RESET)
 
void delay_us(uint32_t us);
void SR04_GetData(void);
 
#endif

添加进工程

3.其他代码

usrat.c中添加

/* USER CODE BEGIN 0 */
#include "stdio.h"
/* USER CODE END 0 */
 
 
 
/* USER CODE BEGIN 1 */
/*********************************************************
*
*重定义 fputc 函数
*
*********************************************************/
int fputc(int ch,FILE *f)
{
	HAL_UART_Transmit (&huart1 ,(uint8_t *)&ch,1,HAL_MAX_DELAY );
	return ch;
}
/* USER CODE END 1 */

main函数

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; Copyright (c) 2022 STMicroelectronics.
  * All rights reserved.</center></h2>
  *
  * This software component is licensed by ST under BSD 3-Clause license,
  * the "License"; You may not use this file except in compliance with the
  * License. You may obtain a copy of the License at:
  *                        opensource.org/licenses/BSD-3-Clause
  *
  ******************************************************************************
  */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "tim.h"
#include "usart.h"
#include "gpio.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "SR04.h"
/* 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 */

/**
  * @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_TIM2_Init();
  MX_USART1_UART_Init();
  /* USER CODE BEGIN 2 */

  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
      
      SR04_GetData(  );
      HAL_Delay(300);
      
    /* 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};

  /** 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 */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

四、效果

HC-SR04模块接线

VCC接5V
GND接地
TRIG接A1
ECHO接A0

五、参考资料：

[1]https://blog.csdn.net/qq_52215423/article/details/131034232?ops_request_misc=&request_id=&biz_id=102&utm_term=stm32%E8%B6%85%E5%A3%B0%E6%B3%A2%E6%B5%8B%E8%B7%9D&utm_medium=distribute.pc_search_result.none-task-blog-2_allsobaiduweb~default-1-131034232.142

[2]https://blog.csdn.net/lwb450921/article/details/123670786?spm=1001.2014.3001.5502

[3]https://blog.csdn.net/weixin_72921448/article/details/127586521?ops_request_misc=%257B%2522request%255Fid%2522%253A%2522171721873616800186519673%2522%252C%2522scm%2522%253A%252220140713.130102334…%2522%257D&request_id=171721873616800186519673&biz_id=0&utm_medium=distribute.pc_search_result.none-task-blog-2_alltop_click~default-4-127586521-null-null.142

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