STM32外部中断初始化

#include "exti.h"  

/******************************************************************************* 

* 函 数 名         : exti_init 

* 函数功能         : 外部中断2端口初始化函数       

* 输    入         : 无 

* 输    出         : 无 

*******************************************************************************/  

void exti_init()  //外部中断初始化  

{  

    GPIO_InitTypeDef GPIO_InitStructure;  

    EXTI_InitTypeDef EXTI_InitStructure;  

    NVIC_InitTypeDef NVIC_InitStructure;  

    /* 开启GPIO时钟 */  

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE);  

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOE,ENABLE);  

    GPIO_InitStructure.GPIO_Pin=k_left;  

    GPIO_InitStructure.GPIO_Mode=GPIO_Mode_IPU;  

    GPIO_InitStructure.GPIO_Speed=GPIO_Speed_50MHz;  

    GPIO_Init(GPIOE,&GPIO_InitStructure);  

    GPIO_EXTILineConfig(GPIO_PortSourceGPIOE, GPIO_PinSource2);//选择GPIO管脚用作外部中断线路  

    //此处一定要记住给端口管脚加上中断外部线路  

    /* 设置外部中断的模式 */   

    EXTI_InitStructure.EXTI_Line=EXTI_Line2;  

    EXTI_InitStructure.EXTI_Mode=EXTI_Mode_Interrupt;  

    EXTI_InitStructure.EXTI_Trigger=EXTI_Trigger_Falling;  

    EXTI_InitStructure.EXTI_LineCmd = ENABLE;  

    EXTI_Init(&EXTI_InitStructure);   

    /* 设置NVIC参数 */    

    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);        

    NVIC_InitStructure.NVIC_IRQChannel = EXTI2_IRQn;    //打开EXTI2的全局中断  

    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0; //抢占优先级为0  

    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;        //响应优先级为0  

    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;           //使能  

    NVIC_Init(&NVIC_InitStructure);           

}