stm32光电传感器测速代码

下面是基于STM32的光电传感器测速代码，假设使用的是PA0和PA1两个引脚接收光电传感器的信号。

#include "stm32f10x.h"

#define LED_PIN     GPIO_Pin_13
#define LED_PORT    GPIOC

#define SENSOR_PIN1 GPIO_Pin_0
#define SENSOR_PIN2 GPIO_Pin_1
#define SENSOR_PORT GPIOA

volatile uint32_t count = 0;
volatile uint32_t speed = 0;

void TIM2_IRQHandler(void)
{
    if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET) {
        TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
        speed = count * 60 / 7.5;
        count = 0;
    }
}

void EXTI0_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line0) != RESET) {
        EXTI_ClearITPendingBit(EXTI_Line0);
        count++;
    }
}

void EXTI1_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line1) != RESET) {
        EXTI_ClearITPendingBit(EXTI_Line1);
        count--;
    }
}

void GPIO_Configuration(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC | RCC_APB2Periph_GPIOA, ENABLE);

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

    GPIO_InitStructure.GPIO_Pin = SENSOR_PIN1 | SENSOR_PIN2;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPD;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(SENSOR_PORT, &GPIO_InitStructure);

    GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource0);
    GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource1);
}

void TIM_Configuration(void)
{
    TIM_TimeBaseInitTypeDef TIM_InitStructure;

    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);

    TIM_InitStructure.TIM_Period = 59999;
    TIM_InitStructure.TIM_Prescaler = 719;
    TIM_InitStructure.TIM_ClockDivision = TIM_CKD_DIV1;
    TIM_InitStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_InitStructure.TIM_RepetitionCounter = 0;
    TIM_TimeBaseInit(TIM2, &TIM_InitStructure);

    TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
    TIM_Cmd(TIM2, ENABLE);
}

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

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);

    EXTI_InitStructure.EXTI_Line = EXTI_Line0;
    EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
    EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising_Falling;
    EXTI_InitStructure.EXTI_LineCmd = ENABLE;
    EXTI_Init(&EXTI_InitStructure);

    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 = EXTI0_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x01;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x00;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    NVIC_InitStructure.NVIC_IRQChannel = EXTI1_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x02;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x00;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
}

int main(void)
{
    GPIO_Configuration();
    TIM_Configuration();
    EXTI_Configuration();

    while (1) {
        if (speed > 0) {
            GPIO_SetBits(LED_PORT, LED_PIN);
        } else {
            GPIO_ResetBits(LED_PORT, LED_PIN);
        }
    }
}

这里使用了定时器和外部中断来计算旋转速度，每次光电传感器发生跳变时，通过外部中断来记录计数。定时器每隔 100ms 触发一次中断，计算出当前的旋转速度，然后将计数器清零。最后通过一个 LED 灯来显示速度是否大于零。需要根据实际情况进行适当的调整。