外部中断实验

外部中断实验

1. 外部中断首先需要进行中断初始化以及使用NVIC设置中断优先级
2. 设置中断响应函数

void EXTIX_Init (void){
    EXTI_InitTypeDef EXTI_InitStructure;
    NVIC_InitTypeDef NVIC_InitStructure;
    KEY_INit();
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE);
    //将中断线2与GPIOE进行映射连接起来
    GPIO_EXTILineConfig(GPIO_PortSourceGPIOE,GPIO_PinSource2);
    //那这个IO口的中断该怎么触发呢，由EXTI_Init()进行实现
    EXTI_InitStructure.EXTI_Line = EXTI_Line2;
    EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
    EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
    EXTI_InitStructure.EXTI_LineCmd = EMABLE;
    EXTI_Init(&EXTI_InitStructure);
    //将中断线3与GPIOE进行映射连接起来
    GPIO_EXTILineConfig(GPIO_PortSourceGPIOE,GPIO_PinSource3);
    //配置这个IO口的中断初始化
  	EXTI_InitStructure.EXTI_Line=EXTI_Line3;
  	EXTI_Init(&EXTI_InitStructure);	
    //将中断线4与GPIOE进行映射连接起来
    GPIO_EXTILineConfig(GPIO_PortSourceGPIOE,GPIO_PinSource4);
    //配置这个IO口的中断初始化
  	EXTI_InitStructure.EXTI_Line=EXTI_Line4;
  	EXTI_Init(&EXTI_InitStructure);	 
    //将中断线0与GPIOA进行映射连接起来
    GPIO_EXTILineConfig(GPIO_PortSourceGPIOA,GPIO_PinSource0); 
	//配置这个IO口的中断初始化
  	EXTI_InitStructure.EXTI_Line=EXTI_Line0;
  	EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;
  	EXTI_Init(&EXTI_InitStructure);	
    
    //中断配置完成后需要配置中断优先级，首先进行中断优先级分组，设置2位抢占优先级
    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);  
    //设置中断线0的中断优先级
    NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;			
  	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x02;	
  	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x03;				
  	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;	
  	NVIC_Init(&NVIC_InitStructure); 
	//设置中断线2中断优先级
    NVIC_InitStructure.NVIC_IRQChannel = EXTI2_IRQn;		
  	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x02;	
  	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x02;					
  	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;								
  	NVIC_Init(&NVIC_InitStructure);
	//设置中断线3中断优先级
  	NVIC_InitStructure.NVIC_IRQChannel = EXTI3_IRQn;			
  	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x02;	
  	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x01;					
  	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;								
  	NVIC_Init(&NVIC_InitStructure);  	
	//设置中断线4中断优先级
	NVIC_InitStructure.NVIC_IRQChannel = EXTI4_IRQn;			
  	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x02;	
  	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x00;				
  	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;							
  	NVIC_Init(&NVIC_InitStructure); 
}

到这里中断的配置以及完成，接下来需要配置中断响应函数：

首先是中断线0的响应函数:

void EXTI0_IRQHandler (void){
    delay_ms(10);//消抖
    if (WK_UP==1){
       BEEP =! BEEP; 
    }
    EXTI_ClearITPendingBit(EXTI_Line0); //清除LINE0上的中断标志位
}

中断线2的响应函数:

void EXTI2_IRQHandler (void){
	delay_ms(10);//消抖
	if (KEY2==0){
		LED0=!LED0;
	}		 
	EXTI_ClearITPendingBit(EXTI_Line2);  //清除LINE2上的中断标志位  
}

中断线3的响应函数:

void EXTI3_IRQHandler (void){
	delay_ms(10);//消抖
	if (KEY1==0){				 
		LED1=!LED1;
	}		 
	EXTI_ClearITPendingBit(EXTI_Line3);  //清除LINE3上的中断标志位  
}

中断线4的响应函数:

void EXTI4_IRQHandler(void)
{
	delay_ms(10);//消抖
	if (KEY0==0){
		LED0=!LED0;
		LED1=!LED1; 
	}		 
	EXTI_ClearITPendingBit(EXTI_Line4);  //清除LINE4上的中断标志位  
}