hcsr04超声波模块stm32代码

以下是使用STM32驱动HC-SR04超声波模块的代码示例：

#include "stm32f10x.h"
#include "delay.h"

#define TRIG_PIN GPIO_Pin_0
#define ECHO_PIN GPIO_Pin_1
#define TRIG_PORT GPIOA
#define ECHO_PORT GPIOA

void HC_SR04_Init(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);

    GPIO_InitStructure.GPIO_Pin = TRIG_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(TRIG_PORT, &GPIO_InitStructure);

    GPIO_InitStructure.GPIO_Pin = ECHO_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
    GPIO_Init(ECHO_PORT, &GPIO_InitStructure);
}

float HC_SR04_ReadDistance(void)
{
    uint32_t time_start = 0, time_stop = 0, time_elapsed = 0;
    float distance = 0;

    GPIO_ResetBits(TRIG_PORT, TRIG_PIN);
    delay_us(2);
    GPIO_SetBits(TRIG_PORT, TRIG_PIN);
    delay_us(10);
    GPIO_ResetBits(TRIG_PORT, TRIG_PIN);

    while (GPIO_ReadInputDataBit(ECHO_PORT, ECHO_PIN) == RESET);
    time_start = TIM_GetCounter(TIM2);
    while (GPIO_ReadInputDataBit(ECHO_PORT, ECHO_PIN) == SET);
    time_stop = TIM_GetCounter(TIM2);

    time_elapsed = time_stop - time_start;
    distance = (float)time_elapsed * 0.0343 / 2;

    return distance;
}

int main(void)
{
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
    TIM_TimeBaseInitTypeDef TIM_InitStructure;
    TIM_InitStructure.TIM_Prescaler = 72 - 1;
    TIM_InitStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_InitStructure.TIM_Period = 0xFFFF;
    TIM_InitStructure.TIM_ClockDivision = TIM_CKD_DIV1;
    TIM_TimeBaseInit(TIM2, &TIM_InitStructure);
    TIM_Cmd(TIM2, ENABLE);

    HC_SR04_Init();

    while (1)
    {
        float distance = HC_SR04_ReadDistance();
        // 处理测量结果
    }
}

该代码使用STM32的GPIO和定时器功能驱动HC-SR04超声波模块，并计算测量结果。其中`TRIG_PIN`和`ECHO_PIN`分别指定了超声波模块的发送和接收引脚，`HC_SR04_Init`函数用于初始化GPIO，`HC_SR04_ReadDistance`函数用于进行一次测量并返回距离值。在`main`函数中，使用定时器功能计算超声波的传播时间，最终计算距离并进行处理。