1、外部中断初始化代码

#include "bsp_exti.h"
/*
    EXTI_Mode_Interrupt = 0x00,
    EXTI_Mode_Event = 0x04
*/
/*
    EXTI_Trigger_Rising = 0x08,
    EXTI_Trigger_Falling = 0x0C,  
    EXTI_Trigger_Rising_Falling = 0x10
*/
void BSP_EXTI_INIT()
{
    //打开时钟
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB,ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE);
    //引脚初始化
    {
        GPIO_InitTypeDef GPIO_InitStruct;
        GPIO_InitStruct.GPIO_Pin  = GPIO_Pin_2;
        GPIO_InitStruct.GPIO_Mode = GPIO_Mode_IPU;
        GPIO_Init(GPIOB,&GPIO_InitStruct);
    }
    //中断线初始化
    {
        EXTI_InitTypeDef EXTI_InitStructure;
        EXTI_InitStructure.EXTI_Line    = EXTI_Line2;    
        EXTI_InitStructure.EXTI_Mode    = EXTI_Mode_Interrupt;    
        EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;
        EXTI_InitStructure.EXTI_LineCmd = ENABLE;
        EXTI_Init(&EXTI_InitStructure);
        //初始化中断线
        GPIO_EXTILineConfig(GPIO_PortSourceGPIOB,GPIO_PinSource2);
    }
    //NVIC初始化
    {
        NVIC_InitTypeDef NVIC_InitStructure;
        NVIC_InitStructure.NVIC_IRQChannel = EXTI2_IRQn;            //使能外部中断通道
        NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;    //抢占优先级2， 
        NVIC_InitStructure.NVIC_IRQChannelSubPriority =        0;    //子优先级0
        NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;                //使能外部中断通道
        NVIC_Init(&NVIC_InitStructure); 
    }
}

2、中断函数使用

void EXTI2_IRQHandler(void)
{
    EXTI_ClearITPendingBit(EXTI_Line2); 
}