STM32-Project17-18:NVIC中断应用概述；EXTI外部中断控制实验；

#include "exti.h"
#include "led.h"
#include "key.h"
 
static void EXTI_NVIC_Config(void){
 
	 NVIC_InitTypeDef   NVIC_InitStruct;
	 NVIC_PriorityGroupConfig( NVIC_PriorityGroup_1);//分组
   NVIC_InitStruct.NVIC_IRQChannel = EXTI4_IRQn;//中断源
	 NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority = 1;//主优先级
	 NVIC_InitStruct.NVIC_IRQChannelSubPriority = 1;//子优先级；
	 NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;//打开大门
	 NVIC_Init(&NVIC_InitStruct);
	
}
 
 
void EXTI_Key0_Config(void){//中断外设事件线初始化
	
	EXTI_InitTypeDef EXTI_InitStructure;//变量定义放最前面
	
	//0初始化NVIC，用于处理中断
	EXTI_NVIC_Config();
	
	//1初始化要链接到exti的GPIO
  KEY0_GPIO_Config();//浮空输入：电平完全由外部决定
	
	//2初始化exti用于产生中断
  RCC_APB2PeriphClockCmd( RCC_APB2Periph_AFIO, ENABLE );//使用 GPIO 之前必须开启 GPIO 端口的时钟；用到 EXTI 必须开启 AFIO 时钟。EXIT外设的小时钟，APB2线上的是大时钟
	GPIO_EXTILineConfig( GPIO_PortSourceGPIOE,  GPIO_PinSource4);//功能框图输入线源配置：对应ARIO外设
	
	EXTI_InitStructure.EXTI_Line = EXTI_Line4;
	EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;//选择中断而非事件
	EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling; //假设默认高电平，按键按下拉低。注意这里引脚跳接线自己接高电平一下
	EXTI_InitStructure.EXTI_LineCmd = ENABLE;//打开小门
	EXTI_Init(&EXTI_InitStructure);
	
	//3编写中断服务函数，在it文件里面
	
	
}

#include "stm32f10x.h"  
#include "led.h" 
#include "key.h"
#include "rcc.h"
#include "exti.h"
 
//key0按键按下检测到中断，LED0就反转一次
 
void delay(uint32_t count){
	for(;count!=0;count--);
}
 
 
int main(void)
{
	 LED0_GPIO_Config();
	 EXTI_Key0_Config();
	
	while (1){
	  
	}
	
}