为什么进入中断函数，就退不出来？？？

Seeking · 发表于 2015-11-5 08:57:46

#include "stm32f10x.h"
#define LED5REV GPIO_WriteBit(GPIOB,GPIO_Pin_5,(BitAction)(1-(GPIO_ReadOutputDataBit(GPIOB,GPIO_Pin_5))))
#define LED5OFF GPIO_SetBits(GPIOB,GPIO_Pin_5)
#define LED5ON GPIO_ResetBits(GPIOB,GPIO_Pin_5)

static __IO uint32_t TimingDelay;
void Delay(__IO uint32_t nTime);

EXTI_InitTypeDef EXTI_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
void Systick()
{
if (SysTick_Config(SystemCoreClock / 1000000))
{
while (1);
}
}

void EXTI0_Config(void)
{

/* Enable GPIOA clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
/* Configure PA.00 pin as input floating */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOA, &GPIO_InitStructure);

/* Enable AFIO clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);

/* Connect EXTI0 Line to PA.00 pin */
GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource0);

/* Configure EXTI0 line */
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);

/* Enable and set EXTI0 Interrupt to the lowest priority */
NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0);
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority =0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
}

void led_init()
{
GPIO_InitTypeDef GPIO_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_Init(GPIOB, &GPIO_InitStructure);
}

int main(void)
{
Systick();
led_init();
EXTI0_Config();
EXTI_GenerateSWInterrupt(EXTI_Line0);//?ú?ú?????í??????
while (1);
}

void Delay(__IO uint32_t nTime)
{
TimingDelay = nTime;

while(TimingDelay != 0);
}

void TimingDelay_Decrement(void)
{
if (TimingDelay != 0x00)
{
TimingDelay--;
}
}

void EXTI0_IRQHandler()
{
Delay(20);
if(EXTI_GetITStatus(EXTI_Line0)==SET)
{
LED5ON;
EXTI_ClearITPendingBit(EXTI_Line0);
}
}

LED5一直亮着？？