原理圖:

頭文件及完整例程下載:http://www.torrancerestoration.com/f/stm32標(biāo)準(zhǔn)例程庫函數(shù).rar
程序分析:
#include "led.h"
#include "delay.h"
#include "key.h"
#include "sys.h"
#include "usart.h"
#include "exti.h"
#include "beep.h"
//STM32開發(fā)板實(shí)驗(yàn)5
//外部中斷實(shí)驗(yàn)
int main(void)
{
delay_init(); //延時(shí)函數(shù)初始化
NVIC_Configuration(); //設(shè)置NVIC中斷分組2:2位搶占優(yōu)先級(jí),2位響應(yīng)優(yōu)先級(jí)
uart_init(9600); //串口初始化為9600
LED_Init(); //初始化與LED連接的硬件接口
// BEEP_Init(); //初始化蜂鳴器端口
KEY_Init(); //初始化與按鍵連接的硬件接口
EXTIX_Init(); //外部中斷初始化
// LED0=0; //點(diǎn)亮LED0
while(1)
{
printf("OK\r\n");
delay_ms(1000);
}
}
//按鍵初始化函數(shù)設(shè)置PC2,3,5為上拉輸入
void KEY_Init(void) //IO初始化
{
GPIO_InitTypeDef GPIO_InitStructure;
//初始化KEY0-->GPIOA.13,KEY1-->GPIOA.15 上拉輸入
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC,ENABLE);//使能PORTA,PORTE時(shí)鐘
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2|GPIO_Pin_3|GPIO_Pin_5;//PE2~4
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU; //設(shè)置成上拉輸入
GPIO_Init(GPIOC, &GPIO_InitStructure);//初始化GPIOE2,3,4
}
初始化中斷時(shí)鐘初始化中斷GPIO口,設(shè)定優(yōu)先級(jí)
void EXTIX_Init(void)
{
EXTI_InitTypeDef EXTI_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
// KEY_Init(); // 按鍵端口初始化
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE); //使能復(fù)用功能時(shí)鐘
//GPIOE.2 中斷線以及中斷初始化配置 下降沿觸發(fā)
GPIO_EXTILineConfig(GPIO_PortSourceGPIOC,GPIO_PinSource2);
EXTI_InitStructure.EXTI_Line=EXTI_Line2; //KEY2
EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
EXTI_InitStructure.EXTI_LineCmd = ENABLE;
EXTI_Init(&EXTI_InitStructure); //根據(jù)EXTI_InitStruct中指定的參數(shù)初始化外設(shè)EXTI寄存器
//GPIOE.3 中斷線以及中斷初始化配置 下降沿觸發(fā) //KEY1
GPIO_EXTILineConfig(GPIO_PortSourceGPIOC,GPIO_PinSource3);
EXTI_InitStructure.EXTI_Line=EXTI_Line3;
EXTI_Init(&EXTI_InitStructure); //根據(jù)EXTI_InitStruct中指定的參數(shù)初始化外設(shè)EXTI寄存器
//GPIOE.4 中斷線以及中斷初始化配置 下降沿觸發(fā) //KEY0
GPIO_EXTILineConfig(GPIO_PortSourceGPIOC,GPIO_PinSource5);
EXTI_InitStructure.EXTI_Line=EXTI_Line5;
EXTI_Init(&EXTI_InitStructure); //根據(jù)EXTI_InitStruct中指定的參數(shù)初始化外設(shè)EXTI寄存器
NVIC_InitStructure.NVIC_IRQChannel = EXTI2_IRQn; //使能按鍵KEY2所在的外部中斷通道
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x02; //搶占優(yōu)先級(jí)2,
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x02; //子優(yōu)先級(jí)2
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //使能外部中斷通道
NVIC_Init(&NVIC_InitStructure);
NVIC_InitStructure.NVIC_IRQChannel = EXTI3_IRQn; //使能按鍵KEY1所在的外部中斷通道
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x02; //搶占優(yōu)先級(jí)2
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x01; //子優(yōu)先級(jí)1
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //使能外部中斷通道
NVIC_Init(&NVIC_InitStructure); //根據(jù)NVIC_InitStruct中指定的參數(shù)初始化外設(shè)NVIC寄存器
NVIC_InitStructure.NVIC_IRQChannel = EXTI9_5_IRQn; //使能按鍵KEY0所在的外部中斷通道
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x02; //搶占優(yōu)先級(jí)2
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x00; //子優(yōu)先級(jí)0
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //使能外部中斷通道
NVIC_Init(&NVIC_InitStructure); //根據(jù)NVIC_InitStruct中指定的參數(shù)初始化外設(shè)NVIC寄存器
}
PC2中斷LED1翻轉(zhuǎn)
void EXTI2_IRQHandler(void)
{
delay_ms(10);//消抖
if(KEY2==0) //按鍵KEY2
{
LED1=!LED1;
}
EXTI_ClearITPendingBit(EXTI_Line2); //清除LINE2上的中斷標(biāo)志位
}
//外部中斷3服務(wù)程序,LED2翻轉(zhuǎn)
void EXTI3_IRQHandler(void)
{
delay_ms(10);//消抖
if(KEY1==0) //按鍵KEY1
{
LED2=!LED2;
}
EXTI_ClearITPendingBit(EXTI_Line3); //清除LINE3上的中斷標(biāo)志位
}
//外部中斷5服務(wù)程序,LED0翻轉(zhuǎn)
void EXTI9_5_IRQHandler(void)
{
delay_ms(10);//消抖
if(KEY0==0) //按鍵KEY0
{
LED0=!LED0;
// LED1=!LED1;
}
EXTI_ClearITPendingBit(EXTI_Line5); //清除LINE4上的中斷標(biāo)志位
} 