/***********************头文件****************************/
#include "exti.h"

/**********************************************
//外部中断初始化程序

***********************************************/
void EXTIX_Init(void)
{
    NVIC_InitTypeDef   NVIC_InitStructure;
    EXTI_InitTypeDef   EXTI_InitStructure;
    
    /***************使能SYSCFG时钟***************/
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);//使能SYSCFG时钟
    
    /***************初始化IO口*******************
      PI4 -> I14   外部中断输入
      PI5 -> I15   外部输入1
     PI6 -> I16   外部输入2
    **********************************************/
	GPIO_InitTypeDef  GPIO_InitStructure;
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOI, ENABLE);//使能GPIOB时钟
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4;//PI4 = I14
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;//普通输入模式
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;//100MHz
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;//上拉
    GPIO_Init(GPIOI, &GPIO_InitStructure);//初始化GPIO
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_6;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;//普通输入模式
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;//100MHz
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;//输入上拉
    GPIO_Init(GPIOI, &GPIO_InitStructure);//初始化GPIO
    
    /***************设置IO口与中断线的映射关系***************/
	SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOI, EXTI_PinSource4);//PI4 连接到中断线4
    
    /***************初始化线上中断，设置触发条件***************/
    EXTI_InitStructure.EXTI_Line = EXTI_Line4;    //选择线上中断
    EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;   //中断事件
    EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling; //下降沿触发
    EXTI_InitStructure.EXTI_LineCmd = ENABLE;//中断线使能
    EXTI_Init(&EXTI_InitStructure);//配置
 
    /***************中断使能***************/
    NVIC_InitStructure.NVIC_IRQChannel = EXTI4_IRQn;//外部中断4
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x01;//抢占优先级1
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x02;//子优先级2
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;//使能外部中断通道
    NVIC_Init(&NVIC_InitStructure);//配置
	   
}