stm32中断控制流水灯开关

下面是一个基于STM32的中断控制流水灯开关的示例代码：

#include "stm32f10x.h"

void delay(uint32_t time);

int main(void)
{
    // 初始化GPIO
    GPIO_InitTypeDef GPIO_InitStructure;
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOB, &GPIO_InitStructure);

    // 初始化NVIC
    NVIC_InitTypeDef NVIC_InitStructure;
    NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x00;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x01;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    // 初始化EXTI
    EXTI_InitTypeDef EXTI_InitStructure;
    EXTI_InitStructure.EXTI_Line = EXTI_Line0;
    EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
    EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
    EXTI_InitStructure.EXTI_LineCmd = ENABLE;
    EXTI_Init(&EXTI_InitStructure);

    // 循环输出流水灯
    uint8_t i = 0;
    while (1)
    {
        GPIO_SetBits(GPIOB, GPIO_Pin_0 << i);
        delay(500000);
        GPIO_ResetBits(GPIOB, GPIO_Pin_0 << i);
        delay(500000);
        i = (i + 1) % 4;
    }
}

void EXTI0_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line0) != RESET)
    {
        // 延时消抖
        delay(100000);

        // 切换流水灯方向
        static uint8_t direction = 0;
        direction = !direction;
        if (direction)
        {
            EXTI->RTSR |= EXTI_Line0;
            EXTI->FTSR &= ~EXTI_Line0;
        }
        else
        {
            EXTI->FTSR |= EXTI_Line0;
            EXTI->RTSR &= ~EXTI_Line0;
        }

        EXTI_ClearITPendingBit(EXTI_Line0);
    }
}

void delay(uint32_t time)
{
    while (time--)
    {
        __NOP();
    }
}

在这个示例代码中，我们使用了STM32F103C8T6开发板上的四个LED灯，它们连接在GPIOB的Pin0~Pin3上。我们通过循环输出流水灯的方式来实现LED灯的闪烁效果。同时，我们还配置了一个外部中断，当按下开发板上的按键时，会触发这个中断，并改变流水灯的方向。具体来说，当按键按下时，我们会切换外部中断的触发方式（从下降沿触发切换到上升沿触发，或者反之），这样就可以实现反向闪烁的效果。