急急！！按一次按键KEY0, 为什么会多次进入中断

qq506124204 · 发表于 2013-7-6 01:03:42

// 初始化外部中断

void InitExti()

{

EXTI_InitTypeDef EXTI_InitStructure;

NVIC_InitTypeDef NVIC_InitStructure;

// RCC使能端口时钟

RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE); // 复用IO 时钟

// 中断线设置(GPIO 寄存器)

GPIO_EXTILineConfig(GPIO_PortSourceGPIOE, GPIO_PinSource4); // KEY0 中断线4

// 初始化

EXTI_InitStructure.EXTI_Line = EXTI_Line4;

EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;

EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;

EXTI_InitStructure.EXTI_LineCmd = ENABLE;

EXTI_Init(&EXTI_InitStructure);

// 中断向量控制器

NVIC_InitStructure.NVIC_IRQChannel = EXTI4_IRQn;

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

NVIC_Init(&NVIC_InitStructure);

}

/*按一次按键KEY0,为什么会多次进入中断*/

void EXTI4_IRQHandler(void)

{

u8 ReadValue=2;

DelayMs(3000);

ReadValue = GPIO_ReadInputDataBit(GPIOE, GPIO_Pin_4);

LedLight(!ReadValue);

USART_SendData(USART1, ReadValue);

EXTI_ClearITPendingBit(EXTI_Line4);

}

liuje · 发表于 2013-7-6 09:40:52

void EXTI4_IRQHandler(void)
{
    u8 ReadValue=2;
    DelayMs(3000);
    ReadValue = GPIO_ReadInputDataBit(GPIOE, GPIO_Pin_4);
    LedLight(!ReadValue);
    USART_SendData(USART1, ReadValue);
    EXTI_ClearITPendingBit(EXTI_Line4);
}

你在中断里头延迟了这么久... 3000ms  .    中断最后你才清除中断旗标允许再次中断.     照理中间不会因为
按键在压下及放开瞬间产生的弹跳杂讯问题.   但你却发生了...     一般按键弹跳周期应该在10ms以内.

但你已经延迟了3000ms,  却又碰到类似弹跳引起多次进入中断...     合理怀疑你那 DelayMs(3000)

没有真正延迟3秒钟.     再查看看吧 .