STM32 HAL/STD库驱动HC-SR04测距

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• ✨说明:本文不介绍HC-SR04原理。

• 📌相关篇《STM32F103VC+DS18B20温度+hc-sr04超声波测距+I2C OLED显示》

• 🌿HAL库实现方法比较简易，只需配置2个IO引脚：一个配置为输入，一个配置为输出即可。
  

• 🌿基于标准库例程，是使用定时器3，输出通道比较模式：TIM_OCMode_PWM1和输入通道捕获上升沿检测实现。

• 🌼HC-SR04
  

📓标准库驱动函数

• 👉🏻使用的是正点原子资料中的标准库工程模版

• 📝stm32f10x_HC-SR04.c

#include "stm32f10x_HC-SR04.h"

extern void EnableHCSR04PeriphClock(void);

static void initMeasureTimer() {
	RCC_ClocksTypeDef RCC_ClocksStatus;
	RCC_GetClocksFreq(&RCC_ClocksStatus);
	uint16_t prescaler = RCC_ClocksStatus.SYSCLK_Frequency / 1000000 - 1; //1 tick = 1us (1 tick = 0.165mm resolution)

	TIM_DeInit(US_TIMER);
	TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStruct;
	TIM_TimeBaseInitStruct.TIM_Prescaler = prescaler;
	TIM_TimeBaseInitStruct.TIM_CounterMode = TIM_CounterMode_Up;
	TIM_TimeBaseInitStruct.TIM_Period = 0xFFFF;
	TIM_TimeBaseInitStruct.TIM_ClockDivision = TIM_CKD_DIV1;
	TIM_TimeBaseInit(US_TIMER, &TIM_TimeBaseInitStruct);

	TIM_OCInitTypeDef TIM_OCInitStruct;
	TIM_OCStructInit(&TIM_OCInitStruct);
	TIM_OCInitStruct.TIM_OCMode = TIM_OCMode_PWM1;
	TIM_OCInitStruct.TIM_OutputState = TIM_OutputState_Enable;
	TIM_OCInitStruct.TIM_Pulse = 15; //us
	TIM_OCInitStruct.TIM_OCPolarity = TIM_OCPolarity_High;
	TIM_OC3Init(US_TIMER, &TIM_OCInitStruct);

	TIM_ICInitTypeDef TIM_ICInitStruct;
	TIM_ICInitStruct.TIM_Channel = TIM_Channel_1;
	TIM_ICInitStruct.TIM_ICPolarity = TIM_ICPolarity_Rising;
	TIM_ICInitStruct.TIM_ICSelection = TIM_ICSelection_DirectTI;
	TIM_ICInitStruct.TIM_ICPrescaler = TIM_ICPSC_DIV1;
	TIM_ICInitStruct.TIM_ICFilter = 0;

	TIM_PWMIConfig(US_TIMER, &TIM_ICInitStruct);
	TIM_SelectInputTrigger(US_TIMER, US_TIMER_TRIG_SOURCE);
	TIM_SelectMasterSlaveMode(US_TIMER, TIM_MasterSlaveMode_Enable);

	TIM_CtrlPWMOutputs(US_TIMER, ENABLE);

	TIM_ClearFlag(US_TIMER, TIM_FLAG_Update);
}

static void initPins() {
	GPIO_InitTypeDef GPIO_InitStructure;
	GPIO_InitStructure.GPIO_Pin = US_TRIG_PIN;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
	GPIO_Init(US_TRIG_PORT, &GPIO_InitStructure);

	GPIO_InitStructure.GPIO_Pin = US_ECHO_PIN;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
	GPIO_Init(US_ECHO_PORT, &GPIO_InitStructure);
}

void InitHCSR04() {
	EnableHCSR04PeriphClock();
	initPins();
	initMeasureTimer();
}

int32_t HCSR04GetDistance() {
	(US_TIMER)->CNT = 0;
	TIM_Cmd(US_TIMER, ENABLE);
	while(!TIM_GetFlagStatus(US_TIMER, TIM_FLAG_Update));
	TIM_Cmd(US_TIMER, DISABLE);
	TIM_ClearFlag(US_TIMER, TIM_FLAG_Update);
	return (TIM_GetCapture2(US_TIMER)-TIM_GetCapture1(US_TIMER))*165/1000;
}

• 📝stm32f10x_HC-SR04.h

#ifndef __STM32F10X_HC_SR04_H_
#define __STM32F10X_HC_SR04_H_

#include "stm32f10x.h"

#define US_TIMER					TIM3

#define US_TRIG_PORT				GPIOB
#define US_TRIG_PIN					GPIO_Pin_0		//TIM Ch3 (trig output)

#define US_ECHO_PORT				GPIOA
#define US_ECHO_PIN					GPIO_Pin_6		//TIM Ch1 (echo input)
#define US_TIMER_TRIG_SOURCE		TIM_TS_TI1FP1

/**
 *	How to use this driver:
 * 	1. Implement EnableHCSR04PeriphClock function and turn on clock for used peripherals
 * 		ex:
 * 		void EnableHCSR04PeriphClock() {
 *			RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
 *			RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
 *			RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
 *		}
 *	2. Call InitHCSR04();
 *	3. Get distance (in mm) using HCSR04GetDistance function.
 *		Value lower than zero means no echo received (distance >3m)
 *		Measuring takes about 65ms
 *
 *	If necessary, change defines above, but be careful, US_ECHO_PIN must be tim ch1
 *	and US_TRIG_PIN must be ch3 or ch4. In case of ch4 change TIM_OC3Init into TIM_OC4Init in stm32f10x_HC-SR04.c file
 */



/**
 * Implement this function. See instruction at the top of this file.
 */
void EnableHCSR04PeriphClock(void);

/**
 * Initialization of HCSR04's peripherals
 */
void InitHCSR04(void);

/**
 * Measure distance and get value in mm. Lower than 0 means no echo signal: distance more than ~3m.
 */
int32_t HCSR04GetDistance(void);

#endif /* STM32F10X_HC_SR04_H_ */

• 📝main.c

#include "sys.h"
#include "delay.h"
#include "usart.h"
#include "stm32f10x_HC-SR04.h"

void EnableHCSR04PeriphClock() {
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
}


int main(void)
{
    u8 t = 0;
    delay_init();	    	 //延时函数初始化
    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2); //设置NVIC中断分组2:2位抢占优先级，2位响应优先级
    uart_init(115200);	 //串口初始化
		InitHCSR04();
	
    while(1)
    {
			int32_t dist = HCSR04GetDistance();
			printf("dist:%d \n",dist);
        delay_ms(800);

    }
}

HAL库工程

• GPIO引脚配置函数：

void MX_GPIO_Init(void)
{

  GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOA_CLK_ENABLE();

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOA, GPIO_PIN_1, GPIO_PIN_RESET);

  /*Configure GPIO pin : PA1 */
  GPIO_InitStruct.Pin = GPIO_PIN_1;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /*Configure GPIO pin : PA2 */
  GPIO_InitStruct.Pin = GPIO_PIN_2;
  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

}

• main.c

/* 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 "usart.h"
#include "gpio.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "stdio.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 */
uint32_t sensor_time;
uint16_t distance;


/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP */
void delay_us(uint32_t udelay);
uint32_t Read_HCSR04(void);
/* 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_USART1_UART_Init();
    /* USER CODE BEGIN 2 */

    /* USER CODE END 2 */

    /* Infinite loop */
    /* USER CODE BEGIN WHILE */
    while(1)
    {
        /* USER CODE END WHILE */

        /* USER CODE BEGIN 3 */
        for(uint8_t i = 8; i > 0; i--)
        {
            sensor_time = Read_HCSR04();			// get the high time
            distance += sensor_time * 165 / 1000;
            HAL_Delay(5);
        }
        distance >>= 3;
        HAL_Delay(1000);
        printf("distance:%d \n", distance);
    }
    /* 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 */
void delay_us(uint32_t udelay)
{
    uint32_t startval, tickn, delays, wait;

    startval = SysTick->VAL;
    tickn = HAL_GetTick();
    //sysc = 72000;  //SystemCoreClock / (1000U / uwTickFreq);
    delays = udelay * 72; //sysc / 1000 * udelay;
    if(delays > startval)
    {
        while(HAL_GetTick() == tickn)
        {

        }
        wait = 72000 + startval - delays;
        while(wait < SysTick->VAL)
        {

        }
    }
    else
    {
        wait = startval - delays;
        while(wait < SysTick->VAL && HAL_GetTick() == tickn)
        {

        }
    }
}
uint32_t Read_HCSR04(void)
{
    uint32_t local_time = 0;

    HAL_GPIO_WritePin(GPIOA, GPIO_PIN_1, GPIO_PIN_SET);		// pull the trig pin high
    delay_us(10);										// wait for 10 us
    HAL_GPIO_WritePin(GPIOA, GPIO_PIN_1, GPIO_PIN_RESET);	// pull the trig pin low

    // wait for the echo pin to go high

    while(!(HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_2)));

    while(HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_2))				// while the pin is high
    {
        local_time++;										// increment local time
        delay_us(1);									// every 1 us
    }

    return local_time * 2;
}
/* 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 */

📓工程源码

• 🌿标准库工程

链接：https://pan.baidu.com/s/1x6Z7IQ_JHMfXKE3z5zFVFQ 
提取码：25q4

• 🌿HAL工程

链接：https://pan.baidu.com/s/12Lzn7WAtL7vbaWgupCI8jQ 
提取码：no8c