STM32_外部中断_笔记

STM32每个IO口都可以作为外部中断输入，

STM32F103支持19个外部中断/事件请求：

line0-15：IO口外部中断

line16：PVD输出

line17：RTC闹钟事件

line18：USB唤醒事件

IO口外部中断函数只有6个：

EXPORT EXTI0_IRQHandler

EXPORT EXTI1_IRQHandler

EXPORT EXTI2_IRQHandler

EXPORT EXTI3_IRQHandler

EXPORT EXTI4_IRQHandler

EXPORT EXTI9_5_IRQHandler

EXPORT EXTI15_10_IRQHandler

INT0案例

void EXIT_init(void)
{
	EXTI_InitTypeDef EXTI_InitStructure;
	NVIC_InitTypeDef NVIC_InitStructure;
	GPIO_InitTypeDef GPIO_InitStructure;

	//初始化中断GPIO
 	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);//使能PORTA时钟
	GPIO_InitStructure.GPIO_Pin  = GPIO_Pin_0;//PA0 PA1
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU; //设置成上拉输入
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz;
 	GPIO_Init(GPIOA, &GPIO_InitStructure);
 	
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE);	//使能复用功能时钟
	
	//配置中断线和中断初始化
	GPIO_EXTILineConfig(GPIO_PortSourceGPIOA,GPIO_PinSource0);
  	EXTI_InitStructure.EXTI_Line=EXTI_Line0;	//KEY2
  	EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;	
  	EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
  	EXTI_InitStructure.EXTI_LineCmd = ENABLE;
  	EXTI_Init(&EXTI_InitStructure);	 	//根据EXTI_InitStruct中指定的参数初始化外设EXTI寄存器


	//中断通道配置
	NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;			
  	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x02;	
  	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x00;					
  	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;		//使能外部中断通道
  	NVIC_Init(&NVIC_InitStructure); 

}

//外部中断0服务程序
void EXTI0_IRQHandler(void)
{
	u8 i, j;
	for(i = 0 ; i < 200 ; i++)
	{
		for(j = 0; j < 200 ; j++);
	}
	
	EXTI_ClearITPendingBit(EXTI_Line0);  //清除LINE0上的中断标志位  
}

INT6_INT7案例

void EXIT6_EXIT7_init(void)
{
	EXTI_InitTypeDef EXTI_InitStructure;
	NVIC_InitTypeDef NVIC_InitStructure;
	GPIO_InitTypeDef GPIO_InitStructure;

	//初始化中断GPIO
 	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB,ENABLE);//使能PORTA时钟
	GPIO_InitStructure.GPIO_Pin  = GPIO_Pin_6|GPIO_Pin_7;//PB6 PB7
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;//设置成上拉输入
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_10MHz;
 	GPIO_Init(GPIOB, &GPIO_InitStructure);
 	
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE);	//使能复用功能时钟
	
	//配置中断线和中断初始化
	GPIO_EXTILineConfig(GPIO_PortSourceGPIOB,GPIO_PinSource6);
  	EXTI_InitStructure.EXTI_Line=EXTI_Line6;	
  	EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;	
  	EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;//下降沿触发  //EXTI_Trigger_Falling_Rising //EXTI_Trigger_Rising_Falling
	EXTI_InitStructure.EXTI_LineCmd = ENABLE;
  	EXTI_Init(&EXTI_InitStructure);	 	//根据EXTI_InitStruct中指定的参数初始化外设EXTI寄存器

	GPIO_EXTILineConfig(GPIO_PortSourceGPIOB,GPIO_PinSource7);
  	EXTI_InitStructure.EXTI_Line=EXTI_Line7;	
  	EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;	
  	EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
  	EXTI_InitStructure.EXTI_LineCmd = ENABLE;
  	EXTI_Init(&EXTI_InitStructure);	 	//根据EXTI_InitStruct中指定的参数初始化外设EXTI寄存器

	//中断通道配置
	NVIC_InitStructure.NVIC_IRQChannel = EXTI9_5_IRQn;			
  	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x02;	
  	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x00;					
  	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;								//使能外部中断通道
  	NVIC_Init(&NVIC_InitStructure); 

}


void EXTI9_5_IRQHandler(void)
{
	if(EXTI_GetITStatus(EXTI_Line6) != RESET)
	{

		EXTI_ClearITPendingBit(EXTI_Line6);
	}	
	else if(EXTI_GetITStatus(EXTI_Line7) != RESET)
	{
		EXTI_ClearITPendingBit(EXTI_Line7);
	}
}