基于stm32的超声波感应灯、

超声波感应灯可以在人体接近时自动开启，人离开后自动关闭。使用STM32单片机可以实现对超声波传感器的控制和LED灯的控制。下面是一个基于STM32的超声波感应灯的示例代码：

#include "stm32f10x.h"
#include "stm32f10x_gpio.h"
#include "stm32f10x_rcc.h"
#include "stm32f10x_exti.h"
#include "misc.h"

#define TRIG_PIN GPIO_Pin_0
#define ECHO_PIN GPIO_Pin_1
#define LED_PIN GPIO_Pin_12

void GPIO_Config(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(GPIOA, &GPIO_InitStructure);

    GPIO_InitStructure.GPIO_Pin = ECHO_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    GPIO_InitStructure.GPIO_Pin = LED_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOB, &GPIO_InitStructure);
}

void EXTI_Config(void)
{
    EXTI_InitTypeDef EXTI_InitStructure;
    NVIC_InitTypeDef NVIC_InitStructure;

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);

    GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource1);

    EXTI_InitStructure.EXTI_Line = EXTI_Line1;
    EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
    EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising_Falling;
    EXTI_InitStructure.EXTI_LineCmd = ENABLE;
    EXTI_Init(&EXTI_InitStructure);

    NVIC_InitStructure.NVIC_IRQChannel = EXTI1_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x0F;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x0F;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
}

void EXTI1_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line1) != RESET)
    {
        EXTI_ClearITPendingBit(EXTI_Line1);
        GPIO_SetBits(GPIOB, LED_PIN);
        TIM_Cmd(TIM2, ENABLE);
    }
}

void TIM_Config(void)
{
    TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);

    TIM_TimeBaseStructure.TIM_Period = 1000;
    TIM_TimeBaseStructure.TIM_Prescaler = 7200;
    TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

    TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);

    NVIC_InitTypeDef NVIC_InitStructure;
    NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x0F;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x0F;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
}

void TIM2_IRQHandler(void)
{
    if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET)
    {
        TIM_Cmd(TIM2, DISABLE);
        GPIO_ResetBits(GPIOB, LED_PIN);
        TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
    }
}

void delay_us(uint32_t us)
{
    uint32_t i;
    while (us--)
    {
        i = 10;
        while (i--)
        {
            asm("nop");
        }
    }
}

void Send_Trigger(void)
{
    GPIO_SetBits(GPIOA, TRIG_PIN);
    delay_us(10);
    GPIO_ResetBits(GPIOA, TRIG_PIN);
}

float Get_Distance(void)
{
    uint32_t temp = 0;
    float distance = 0;
    while (GPIO_ReadInputDataBit(GPIOA, ECHO_PIN) == RESET);
    TIM_Cmd(TIM3, ENABLE);
    while (GPIO_ReadInputDataBit(GPIOA, ECHO_PIN) == SET)
    {
        temp++;
        delay_us(10);
        if (temp > 5000)
        {
            break;
        }
    }
    TIM_Cmd(TIM3, DISABLE);
    distance = temp * 0.034 / 2;
    return distance;
}

int main(void)
{
    GPIO_Config();
    EXTI_Config();
    TIM_Config();
    TIM_Cmd(TIM3, ENABLE);
    while (1)
    {
        Send_Trigger();
        float distance = Get_Distance();
        if (distance > 0 && distance < 30)
        {
            GPIO_SetBits(GPIOB, LED_PIN);
            TIM_Cmd(TIM2, ENABLE);
        }
        else
        {
            GPIO_ResetBits(GPIOB, LED_PIN);
            TIM_Cmd(TIM2, DISABLE);
        }
        delay_us(500);
    }
}

上述代码中使用了PA0作为超声波传感器的触发引脚，PA1作为接受引脚，PB12作为LED控制引脚。在程序中使用了定时器控制LED的开关，当有人接近时，开启定时器，一段时间后关闭LED。在主函数中使用了Send_Trigger()函数发送超声波信号，Get_Distance()函数返回测量到的距离，根据测量到的距离判断是否有人接近，从而控制LED的开关。