【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PC4void 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)  {  }}