stm32四个按键扫描的代码程序，要求有消抖，非延时

下面是一个带有消抖功能的STM32四个按扫描代码程序，使用了外部中断来实现，而不是延时方式：

#include "stm32f4xx.h"

#define KEY1_PIN GPIO_Pin_0
#define KEY2_PIN GPIO_Pin_1
#define KEY3_PIN GPIO_Pin_2
#define KEY4_PIN GPIO_Pin_3

void GPIO_Configuration(void);
void EXTI_Configuration(void);
void Delay(uint32_t delay);

int main(void)
{
    GPIO_Configuration();
    EXTI_Configuration();
    
    while (1)
    {
        // 主循环中执行其他操作
        
        // 检测按键是否按下
        if (EXTI_GetITStatus(EXTI_Line0) != RESET)
        {
            // 处理按键1的操作
            EXTI_ClearITPendingBit(EXTI_Line0);
        }
        else if (EXTI_GetITStatus(EXTI_Line1) != RESET)
        {
            // 处理按键2的操作
            EXTI_ClearITPendingBit(EXTI_Line1);
        }
        else if (EXTI_GetITStatus(EXTI_Line2) != RESET)
        {
            // 处理按键3的操作
            EXTI_ClearITPendingBit(EXTI_Line2);
        }
        else if (EXTI_GetITStatus(EXTI_Line3) != RESET)
        {
            // 处理按键4的操作
            EXTI_ClearITPendingBit(EXTI_Line3);
        }
        
        // 主循环中执行其他操作
    }
}

void GPIO_Configuration(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
    
    // 配置按键引脚为输入模式
    GPIO_InitStructure.GPIO_Pin = KEY1_PIN | KEY2_PIN | KEY3_PIN | KEY4_PIN;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
}

void EXTI_Configuration(void)
{
    EXTI_InitTypeDef EXTI_InitStructure;
    NVIC_InitTypeDef NVIC_InitStructure;
    
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);
    
    // 配置外部中断线0-3对应的引脚
    SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA, EXTI_PinSource0);
    SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA, EXTI_PinSource1);
    SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA, EXTI_PinSource2);
    SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA, EXTI_PinSource3);
    
    // 配置外部中断线0-3为下降沿触发
    EXTI_InitStructure.EXTI_Line = EXTI_Line0 | EXTI_Line1 | EXTI_Line2 | EXTI_Line3;
    EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
    EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
    EXTI_InitStructure.EXTI_LineCmd = ENABLE;
    EXTI_Init(&EXTI_InitStructure);
    
    // 配置外部中断线0-3的中断优先级
    NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x00;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x00;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
    
    NVIC_InitStructure.NVIC_IRQChannel = EXTI1_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x00;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x01;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
    
    NVIC_InitStructure.NVIC_IRQChannel = EXTI2_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x00;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x02;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
    
    NVIC_InitStructure.NVIC_IRQChannel = EXTI3_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x00;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x03;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
}

void Delay(uint32_t delay)
{
    while (delay--);
}

void EXTI0_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line0) != RESET)
    {
        Delay(10000); // 消抖延时
        
        if (GPIO_ReadInputDataBit(GPIOA, KEY1_PIN) == 0)
        {
            // 处理按键1的操作
        }
        
        EXTI_ClearITPendingBit(EXTI_Line0);
    }
}

void EXTI1_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line1) != RESET)
    {
        Delay(10000); // 消抖延时
        
        if (GPIO_ReadInputDataBit(GPIOA, KEY2_PIN) == 0)
        {
            // 处理按键2的操作
        }
        
        EXTI_ClearITPendingBit(EXTI_Line1);
    }
}

void EXTI2_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line2) != RESET)
    {
        Delay(10000); // 消抖延时
        
        if (GPIO_ReadInputDataBit(GPIOA, KEY3_PIN) == 0)
        {
            // 处理按键3的操作
        }
        
        EXTI_ClearITPendingBit(EXTI_Line2);
    }
}

void EXTI3_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line3) != RESET)
    {
        Delay(10000); // 消抖延时
        
        if (GPIO_ReadInputDataBit(GPIOA, KEY4_PIN) == 0)
        {
            // 处理按键4的操作
        }
        
        EXTI_ClearITPendingBit(EXTI_Line3);
    }
}

这段代码使用了外部中断来实现按键扫描，以避免使用延时方式进行消抖。首先，在`GPIO_Configuration`函数中，配置了按键引脚为输入模式。然后，在`EXTI_Configuration`函数中，配置了外部中断线0-3对应的引脚，并设置触发方式为下降沿触发。同时，还配置了外部中断的优先级。在中断服务函数中，使用了一个简单的延时函数来进行消抖，并通过读取引脚状态来判断按键是否按下，然后执行相应的操作。请根据你的实际硬件连接和需求进行适当修改。