基于STM32实现流水灯【Proteus仿真】

详情更多 wechat：嵌入式工程师成长日记

https://mp.weixin.qq.com/s?__biz=Mzg4Mzc3NDUxOQ==&mid=2247485624&idx=1&sn=4e553234c2624777409bd2067a07aad8&chksm=cf430de0f83484f6189b119d9d83ea6e6f2a85d13afaa04d218483918231c38e6382d3007061&token=767249363&lang=zh_CN#rdhttps://mp.weixin.qq.com/s?__biz=Mzg4Mzc3NDUxOQ==&mid=2247485624&idx=1&sn=4e553234c2624777409bd2067a07aad8&chksm=cf430de0f83484f6189b119d9d83ea6e6f2a85d13afaa04d218483918231c38e6382d3007061&token=767249363&lang=zh_CN#rd

通过配置寄存器初始化LED：

代码：

//LED IO初始化void LED_Init(void){  RCC->APB2ENR|=1<<4;    //使能PORTC时钟  GPIOC->CRL&=0X00000000;//清零  GPIOC->CRL|=0X33333333;//推挽50MHz输出  GPIOC->ODR=0X00FF;      //输出高}

①CRL寄存器(端口配置低寄存器)：

②APB2外设时钟使能寄存器：

③ODR端口输出数据寄存器：

总结：

STM32每个IO端口都有7个寄存器控制：

1.两个32位端口配置寄存器-- CRL和CRH
2.两个32位数据寄存器-- IDR和ODR
3.一个32位置位/复位寄存器-- BSRR
4.一个16位复位寄存器-- BRR
5.一个32位锁存寄存器-- LCKR
主程序（main.c）:

#include "main.h"

void KEY_IO_Init(void);//按键初始化
void EXTIx_Init(void);//外部中断
void EXTI0_IRQHandler(void);
void EXTI1_IRQHandler(void);
//LED IO初始化
void LED_Init(void)
{
  RCC->APB2ENR|=1<<4;    //使能PORTC时钟
  GPIOC->CRL&=0X00000000;//清零
  GPIOC->CRL|=0X33333333;//推挽50MHz输出
  GPIOC->ODR=0X00FF;      //输出高
}


int main(void){
  uint8_t count_i;
  NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);//中断向量分组 2

  KEY_IO_Init();
  EXTIx_Init();//外部中断初始化
  while(1){  
  LED_Init();//初始化与LED连接IO口
  while(1)
  {  
  
  }
    }
  return 0;
}


void KEY_IO_Init(void)//按键初始化
{
   GPIO_InitTypeDef  GPIO_InitStructure;   
   RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);   //使能PB端口时钟
   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;         //按键输入端口配置
   GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;     
   GPIO_Init(GPIOB, &GPIO_InitStructure);  
}  
void EXTIx_Init(void)//外部中断
{
  NVIC_InitTypeDef NVIC_InitStructure;  //NVIC寄存器结构体变量
  EXTI_InitTypeDef EXTI_InitStructure;  //外部中断相关寄存器结构体变量
  
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE); //使能IO复用功能时钟
  
  GPIO_EXTILineConfig(GPIO_PortSourceGPIOB,GPIO_PinSource0); //
  GPIO_EXTILineConfig(GPIO_PortSourceGPIOB,GPIO_PinSource1); //
  GPIO_EXTILineConfig(GPIO_PortSourceGPIOB,GPIO_PinSource2); //
  
  //配置外部中断4相关寄存器
  EXTI_InitStructure.EXTI_Line = EXTI_Line0|EXTI_Line1|EXTI_Line2;
  EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
  EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
  
  EXTI_Init(&EXTI_InitStructure);
  
  //中断通道使能
  NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;//使能外部中断通道0
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2; //设置抢占优先级2
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;//设置响应优先级2
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  
  NVIC_Init(&NVIC_InitStructure);
  
    //中断通道使能
  NVIC_InitStructure.NVIC_IRQChannel = EXTI1_IRQn;//使能外部中断通道1
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2; //设置抢占优先级2
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;//设置响应优先级2
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  
  NVIC_Init(&NVIC_InitStructure);
  
    //中断通道使能
  NVIC_InitStructure.NVIC_IRQChannel = EXTI2_IRQn;//使能外部中断通道2
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2; //设置抢占优先级2
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;//设置响应优先级2
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  
  NVIC_Init(&NVIC_InitStructure);
  
  
}

void EXTI0_IRQHandler(void)
{
      int i;
  for(i=0;i<8;i++)
    {
      GPIOC->ODR=~(1<<i);//输出低
      delay_ms(500);
    }
    GPIOC->ODR=0xff;
  EXTI_ClearITPendingBit(EXTI_Line4);//清除中断挂起标志位
}
void EXTI1_IRQHandler(void)
{
      int i;
  for(i=8;i>=0;i--)
    {
      GPIOC->ODR=~(1<<i);//输出低
      delay_ms(500);
    }
    GPIOC->ODR=0xff;
  EXTI_ClearITPendingBit(EXTI_Line4);//清除中断挂起标志位
}