STM32学习和实践笔记（19）：按键控制实验（用STM32的外部中断的方式实现）

花了两小时，对照着视频的讲解，终于成功做完这个实验~~

代码如下：

main.c

#include "system.h"
#include "led.h"
#include "SysTick.h"
#include "beep.h"
#include "DigitalTube.h"
#include "key.h"
#include "exti.h"


int main()
{
	u8 i=0;
	SysTick_Init(72);
	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);//中断优先级分组
	LED_Init();
//	BEEP_Init();
//	DigitalTube_Init();
	key_Init();
	My_Exti_Init();
	

	
	while(1)
	{
		
		i++;
		if(i%20 ==0)
		{
			led1=!led1;//LED1闪
		}
		delay_ms(10);
		
	}
}

exti.c

#include "exti.h"
#include "SysTick.h"
#include "key.h"
#include "led.h"


void My_Exti_Init(void) //因为Exti_Init函数名已在库函数中使用了，所以这里取这个名称
{
		NVIC_InitTypeDef NVIC_InitStructure;
		EXTI_InitTypeDef EXTI_InitStructure;
	
	
	//（1）使能IO口时钟，配置IO口模式为输入,这一步在key_Init()已做了，所以这里不需要
	
	//（2）开启 AFIO 时钟，设置 IO 口与中断线的映射关系
	
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE);//开启 AFIO 时钟
	GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource0);//配置PA0为EXT0的输入线
	GPIO_EXTILineConfig(GPIO_PortSourceGPIOE, GPIO_PinSource2);//配置PE2为EXT2的输入线
	GPIO_EXTILineConfig(GPIO_PortSourceGPIOE, GPIO_PinSource3);//配置PE3为EXT3的输入线
	GPIO_EXTILineConfig(GPIO_PortSourceGPIOE, GPIO_PinSource4);//配置PE4为EXT4的输入线
	
		//（3）配置中断分组（NVIC），中断分组NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);放在main里了,
		// 并对中断分组初始化以及使能中断
	

	
	NVIC_InitStructure.NVIC_IRQChannel=	EXTI0_IRQn;
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority =2;
	NVIC_InitStructure.NVIC_IRQChannelSubPriority =3;
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
	NVIC_Init(&NVIC_InitStructure);
	
	NVIC_InitStructure.NVIC_IRQChannel=	EXTI2_IRQn;
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority =2;
	NVIC_InitStructure.NVIC_IRQChannelSubPriority =2;
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
	NVIC_Init(&NVIC_InitStructure);
	
	NVIC_InitStructure.NVIC_IRQChannel=	EXTI3_IRQn;
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority =2;
	NVIC_InitStructure.NVIC_IRQChannelSubPriority =1;
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
	NVIC_Init(&NVIC_InitStructure);
	
	NVIC_InitStructure.NVIC_IRQChannel=	EXTI4_IRQn;
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority =2;
	NVIC_InitStructure.NVIC_IRQChannelSubPriority =0;
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
	NVIC_Init(&NVIC_InitStructure);

		//（4）初始化EXTI



	//配置EXTI_Line0的模式、触发方式并打开
	EXTI_InitStructure.EXTI_Line = EXTI_Line0;
	EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
	EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;
	EXTI_InitStructure.EXTI_LineCmd = ENABLE;
	EXTI_Init(&EXTI_InitStructure);

	//配置EXTI_Line2,3,4的模式、触发方式并打开
	EXTI_InitStructure.EXTI_Line = EXTI_Line2|EXTI_Line3|EXTI_Line4;
	EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
	EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
	EXTI_InitStructure.EXTI_LineCmd = ENABLE;
	EXTI_Init(&EXTI_InitStructure);

	
}

//以下是中断服务程序

void EXTI0_IRQHandler(void)
{
 if(EXTI_GetITStatus(EXTI_Line0)==1) //判断是否有按键按下而产生外部中断
 {
	 delay_ms(10);//消除抖动
	 if(K_UP ==1)
	 {
		 led2 = ~led2;
	 }
	 
 }
 EXTI_ClearITPendingBit(EXTI_Line0);
 
 }

void EXTI2_IRQHandler(void)
{
 if(EXTI_GetITStatus(EXTI_Line2)==1) //判断是否有按键按下而产生外部中断
 {
	 delay_ms(10);//消除抖动
	 if(K_LEFT ==0)
	 {
		 led3 = ~led3;
	 }
	 
 }
 EXTI_ClearITPendingBit(EXTI_Line2);
 
 }
	

void EXTI3_IRQHandler(void)
{
 if(EXTI_GetITStatus(EXTI_Line3)==1) //判断是否有按键按下而产生外部中断
 {
	 delay_ms(10);//消除抖动
	 if(K_DOWN ==0)
	 {
		 led4 = ~led4;
	 }
	 
 }
 EXTI_ClearITPendingBit(EXTI_Line3);
 
 }

void EXTI4_IRQHandler(void)
{
 if(EXTI_GetITStatus(EXTI_Line4)==1) //判断是否有按键按下而产生外部中断
 {
	 delay_ms(10);//消除抖动
	 if(K_RIGHT ==0)
	 {
		 led5 = ~led5;
	 }
	 
 }
 EXTI_ClearITPendingBit(EXTI_Line4);
 
 }

exti.h

#ifndef _exti_H
#define _exti_H

#include "system.h"

void My_Exti_Init(void) ;


#endif