前言

本篇文章属于stm32单片机（以下简称单片机）的学习笔记，来源于B站教学视频。下面是这位up主的视频链接。本文为个人学习笔记，只能做参考，细节方面建议观看视频，肯定受益匪浅。

STM32入门教程-2023版 细致讲解 中文字幕_哔哩哔哩_bilibili

一、 stm32中断

二、NVIC基本结构

 三、NVIC优先级分组

四、EXTI简介 

五、EXTI基本结构

 六、AFIO复用IO口

七、EXTI框图

 

八、旋转编码器介绍

不同方向转动编码器会产生如下波形

九、实例一（对射式红外传感器计次）

1. 写初始化函数

（1）配置时钟（GPIO口和AFIO口的）（EXTI和NVIC的时钟自动是开启的，其中因为NVIC是内核的外设，RCC管的是内核外的外设） 

（2）配置GPIO口

（3）配置AFIO外部中断引脚选择

（4）配置EXTI，EXTI初始化

（5）配置NVIC

2.中断函数

去启动文件找中断函数的函数名

CountSensor.c 

#include "stm32f10x.h"                  // Device header
#include "Delay.h"

uint16_t CountSensor_Count;

void CountSensor_Init(void)
{
	//开启时钟
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
	
	//配置GPIO口
	GPIO_InitTypeDef GPIO_InitStructure;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_14;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOB, &GPIO_InitStructure);
	
	//配置AFIO外部中断引脚选择
	GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource14);
	
	//配置EXTI
	EXTI_InitTypeDef EXTI_InitStructure;
	EXTI_InitStructure.EXTI_Line = EXTI_Line14;
	EXTI_InitStructure.EXTI_LineCmd = ENABLE;
	EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
	EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;//不遮挡时，灯亮，发送0；遮挡时，灯灭，发送1
	EXTI_Init(&EXTI_InitStructure);
	
	
	//配置NVIC
	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
	NVIC_InitTypeDef NVIC_InitStructure;
	NVIC_InitStructure.NVIC_IRQChannel = EXTI15_10_IRQn; 
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
	NVIC_Init(&NVIC_InitStructure);
}

uint16_t CountSensor_Get(void)
{
	return CountSensor_Count;
}

void EXTI15_10_IRQHandler(void)
{
	if (EXTI_GetITStatus(EXTI_Line14) == SET)
	{
		Delay_ms(500);
		CountSensor_Count++;
		EXTI_ClearITPendingBit(EXTI_Line14);
	}
}

 

十、实例二（旋转编码器计次）

1. 写初始化函数

同上

2.两个中断函数来判断旋转的方向

 Encoder.c

 

#include "stm32f10x.h"                  // Device header

int16_t Encoder_Count;

/**
  * @brief  旋转编码器初始化
  * @param  无
  * @retval 无
  */
void Encoder_Init(void)
{
	//开启时钟
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
	
	//配置GPIO口
	GPIO_InitTypeDef GPIO_InitStructure;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_Init(GPIOB, &GPIO_InitStructure);
	
	//配置AFIO外部中断引脚选择
	GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource0);
	GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource1);
	
	//配置EXTI
	EXTI_InitTypeDef EXTI_InitStructure;
	EXTI_InitStructure.EXTI_Line = EXTI_Line0 | EXTI_Line1;
	EXTI_InitStructure.EXTI_LineCmd = ENABLE;
	EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
	EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
	EXTI_Init(&EXTI_InitStructure);
	
	
	//配置NVIC
	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
	
	NVIC_InitTypeDef NVIC_InitStructure;
	NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn; 
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
	NVIC_Init(&NVIC_InitStructure);

	NVIC_InitStructure.NVIC_IRQChannel = EXTI1_IRQn; 
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;
	NVIC_Init(&NVIC_InitStructure);
}

/**
  * @brief  获取计数值
  * @param  无
  * @retval Temp，计数值
  */
int16_t Encoder_Get(void)
{
	int16_t Temp;
	Temp = Encoder_Count;
	Encoder_Count = 0;
	return Temp;
}

/**
  * @brief  PB0口中断函数
  * @param  无
  * @retval 无
  */
void EXTI0_IRQHandler(void)
{
	if (EXTI_GetITStatus(EXTI_Line0) == SET)
	{
		if (GPIO_ReadInputDataBit(GPIOB,GPIO_Pin_1)==0)
		{
			Encoder_Count--;
		}
		
		EXTI_ClearITPendingBit(EXTI_Line0);
	}
}

/**
  * @brief  PB1口中断函数
  * @param  无
  * @retval 无
  */
void EXTI1_IRQHandler(void)
{
	if (EXTI_GetITStatus(EXTI_Line1) == SET)
	{
		if (GPIO_ReadInputDataBit(GPIOB,GPIO_Pin_0)==0)
		{
			Encoder_Count++;
		}
		
		EXTI_ClearITPendingBit(EXTI_Line1);
	}
}