【读书笔记】EXTI外部中断 实例

本次使用开发板：
STM32f2XX系列

本次勾选的驱动列表如下：

Core
Startup
Framework ---包含msci,h、stm32f2xx_conf.h，不需要额外copy文件
RCC ---包含GPIO时钟和 SYSCFG时钟，SYSCFG时钟是因为配置中断源需要
GPIO ----指示灯、按键
EXTI ---外部中断，本次主角
SYSCFG --主要配置GPIOX引脚作为中断输入源

stm32f2xx_exti.c中记载了EXTI驱动的使用方法：



main文件如下：

#include "stm32f2xx_conf.h"
//按键对应引脚是PD7
//LED灯对应引脚是PC4

void BSP_LED_Init()
{
GPIO_InitTypeDef GPIOInitStructure;

RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC ,ENABLE);

GPIOInitStructure.GPIO_Mode = GPIO_Mode_OUT;
GPIOInitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIOInitStructure.GPIO_OType = GPIO_OType_PP;

GPIOInitStructure.GPIO_Pin = GPIO_Pin_4;
GPIO_Init(GPIOC,&GPIOInitStructure);

}

void BSP_EXTI_Init()
{
EXTI_InitTypeDef EXTIInitStructure;
GPIO_InitTypeDef GPIOInitStructure;

RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD ,ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);

GPIOInitStructure.GPIO_Mode = GPIO_Mode_IN;
GPIOInitStructure.GPIO_PuPd = GPIO_PuPd_UP;

GPIOInitStructure.GPIO_Pin = GPIO_Pin_7;
GPIO_Init(GPIOD,&GPIOInitStructure);

//配置PD7为中断输入源，需启用SYSCFG时钟
SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOD,EXTI_PinSource7);

EXTIInitStructure.EXTI_Line = EXTI_Line7;
EXTIInitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
EXTIInitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
EXTIInitStructure.EXTI_LineCmd = ENABLE;

EXTI_Init(&EXTIInitStructure);
}
void EXTI9_5_IRQHandler(void)
{
if(RESET != EXTI_GetFlagStatus(EXTI_Line7) )
{
EXTI_ClearITPendingBit(EXTI_Line7);
GPIO_ToggleBits(GPIOC,GPIO_Pin_4);
}
}
void BSP_NVIC_Init()
{
NVIC_InitTypeDef NVICInitStructure;
NVICInitStructure.NVIC_IRQChannel = EXTI9_5_IRQn;
NVICInitStructure.NVIC_IRQChannelCmd = ENABLE;
NVICInitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVICInitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_Init(&NVICInitStructure);
}

int main(void)
{

BSP_LED_Init();
BSP_EXTI_Init();
BSP_NVIC_Init();

GPIO_SetBits(GPIOC,GPIO_Pin_4);
while(1)
{

}
}