外部中断

按键触发外部中断

 1.1EXTI简介

STM32F10x外部中断/事件控制器（EXTI）包含多达20个用于产生事件/中断请求的边沿检测器。EXTI的每根输入线都可单独进行配置，以选择类型（中断或事件）和相应的触发事件（上升沿触发、下降沿触发或边沿触发），还可以独立地被屏蔽。

 

3.或门电路，只要有一个高电平就为高电平

4.与门电路，都是1才为1,1&1=1，取决于3输出，对应的~请求挂起寄存器

脉冲信号~定时器

APB2总线上，外设时钟

 

   通道名

k_up是上升沿

k1,k2,k3是下降沿，加上拉电阻

 

以上是程序步骤

EXTI.C

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

void My_EXTI_Init()
{
NVIC_InitTypeDef NVIC_InitStructure;//结构体初始化
EXTI_InitTypeDef EXTI_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE);//开启AFIO

GPIO_EXTILineConfig(GPIO_PortSourceGPIOA,GPIO_PinSource0);//IO口与中断线的映射
GPIO_EXTILineConfig(GPIO_PortSourceGPIOE,GPIO_PinSource1);
GPIO_EXTILineConfig(GPIO_PortSourceGPIOE,GPIO_PinSource2);
GPIO_EXTILineConfig(GPIO_PortSourceGPIOE,GPIO_PinSource3);

NVIC_InitStructure.NVIC_IRQChannel=EXTI0_IRQn;//中断NVIC
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=2;//抢占式优先级
NVIC_InitStructure.NVIC_IRQChannelSubPriority=3; //响应优先级,0到3选择
NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE;
NVIC_Init(&NVIC_InitStructure);

NVIC_InitStructure.NVIC_IRQChannel=EXTI2_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=2;//抢占式优先级
NVIC_InitStructure.NVIC_IRQChannelSubPriority=2; //响应优先级
NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE;
NVIC_Init(&NVIC_InitStructure);

NVIC_InitStructure.NVIC_IRQChannel=EXTI3_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=2;//抢占式优先级
NVIC_InitStructure.NVIC_IRQChannelSubPriority=1; //响应优先级
NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE;
NVIC_Init(&NVIC_InitStructure);

NVIC_InitStructure.NVIC_IRQChannel=EXTI4_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=2;//抢占式优先级
NVIC_InitStructure.NVIC_IRQChannelSubPriority=0; //响应优先级，数字越小，越高
NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE;
NVIC_Init(&NVIC_InitStructure);

EXTI_InitStructure.EXTI_Line=EXTI_Line0;//外部中断
EXTI_InitStructure.EXTI_Mode=EXTI_Mode_Interrupt;
EXTI_InitStructure.EXTI_Trigger=EXTI_Trigger_Rising;
EXTI_InitStructure.EXTI_LineCmd=ENABLE;
EXTI_Init(&EXTI_InitStructure);

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);


}

void EXTI0_IRQHandler(void)//外部中断
{
if(EXTI_GetITStatus(EXTI_Line0)==1)//获取中断标志
{
delay_ms(10);//消抖
if(K_UP==1) //判断
{
led2=0; //亮
}
}
EXTI_ClearITPendingBit(EXTI_Line0);//清除标志
}

void EXTI2_IRQHandler(void)//外部中断
{
if(EXTI_GetITStatus(EXTI_Line2)==1)//获取中断标志
{
delay_ms(10);//消抖
if(K_LEFT==0)//连接地线
{
led3=1; //灭
}
}
EXTI_ClearITPendingBit(EXTI_Line2);//清除标志
}

void EXTI3_IRQHandler(void)//外部中断
{
if(EXTI_GetITStatus(EXTI_Line3)==1)//获取中断标志
{
delay_ms(10);//消抖
if(K_DOWN==0)//连接地线
{
led2=1; //灭
}
}
EXTI_ClearITPendingBit(EXTI_Line3);//清除标志
}

void EXTI4_IRQHandler(void)//外部中断
{
if(EXTI_GetITStatus(EXTI_Line4)==1)//获取中断标志
{
delay_ms(10);//消抖
if(K_RIGHT==0)//连接地线
{
led3=0; //亮
}
}
EXTI_ClearITPendingBit(EXTI_Line4);//清除标志
}

exti.h

#ifndef _exti_H
#define _exti_H

#include "system.h"

void My_EXTI_Init(void);

#endif

 

main.c

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

int main()
{
u8 i=0;
SysTick_Init(72);//72M
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
LED_Init();//初始化
KEY_Init();
My_EXTI_Init();

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

 

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