Lesson 5 - key control LED

Catalog

Preface

One 、 connection

Two 、 Modular programming

1. Write LED part

LED.c

2. Brief introduction GPIO_ReadOutputDataBit function

LED.h

3. Write key part

key.c

main.c

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Preface

I introduced some GPIO The correlation function of , Integration , Write a small experiment —— Key control LED

One 、 connection

Two 、 Modular programming

Because the experiment involves multiple peripherals , All the code written in one file is too messy , Nor is it suitable for directly using a module in the future

（ Because some code is relatively simple , For example, delay function code , Just use it directly in the future ）.

1. Write LED part

LED.c

It is recommended to create a new... In the project folder hardware Folder , In the future, the peripherals will be placed in hardware in , As shown in the figure ：

  On the first code ：LED.c

#include "stm32f10x.h"                  // Device header


void LED_Init()
{
			RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);
			GPIO_InitTypeDef GPIO_InitStructure;
			GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP ;
			GPIO_InitStructure.GPIO_Pin  = GPIO_Pin_1 | GPIO_Pin_2 ;
			GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz ;
			GPIO_Init(GPIOA,&GPIO_InitStructure);
			GPIO_SetBits(GPIOA, GPIO_Pin_1 | GPIO_Pin_2); // Keep... On power LED It's out 

}

void LED1_ON(void)
{
		GPIO_ResetBits(GPIOA,GPIO_Pin_1); // Light on 
}
void LED1_OFF(void)
{
		GPIO_SetBits(GPIOA,GPIO_Pin_1);  // The light goes out 
}
void LED1_turn(void)   // Press the key     If the output 0, Set up 1, Otherwise, set 0, In this way, the level reversal is realized , namely GPIO_ReadOutputDataBit The meaning of function 
{
	if(GPIO_ReadOutputDataBit(GPIOB,GPIO_Pin_1)==0)
	{
		GPIO_SetBits(GPIOA,GPIO_Pin_1);
	}
	else
	{
		GPIO_ResetBits(GPIOA,GPIO_Pin_1);		
	}
}
void LED2_ON(void)
{
		GPIO_ResetBits(GPIOA,GPIO_Pin_2);
}
void LED2_OFF(void)
{	
		GPIO_SetBits(GPIOA,GPIO_Pin_2);
}
void LED2_turn(void)
{
	if(GPIO_ReadOutputDataBit(GPIOB,GPIO_Pin_2)==0)
	{
		GPIO_SetBits(GPIOA,GPIO_Pin_2);
	}
	else
	{
		GPIO_ResetBits(GPIOA,GPIO_Pin_2);		
	}
}

stay LED Modular GPIO In the initialization , First of all, I'll give it to you LED High level , Ensure that when powered on LED Is off .

2. Brief introduction GPIO_ReadOutputDataBit function

stay LED Inversion level function involves GPIO_ReadOutputDataBit function , So the following is a brief introduction to this function ：

This function functions as , Read the output of the specified port pin

Let's look at the function definition first ：

uint8_t GPIO_ReadOutputDataBit(GPIO_TypeDef* GPIOx, uint16_t GPIO_Pin)
{
      uint8_t bitstatus = 0x00;
      /* Check the parameters */
      assert_param(IS_GPIO_ALL_PERIPH(GPIOx));
      assert_param(IS_GET_GPIO_PIN(GPIO_Pin)); 
  
      if ((GPIOx->ODR & GPIO_Pin) != (uint32_t)Bit_RESET)
      {
        bitstatus = (uint8_t)Bit_SET;
      }
      else
      {
        bitstatus = (uint8_t)Bit_RESET;
      }
      return bitstatus;
}

You can see , This function is the same as before SetBits Equal function usage is no different , At this time LED.c In the said ： When the key is pressed , If the output 0, Set up 1, Otherwise, set 0, In this way, the level reversal is realized , This is also used at this moment GPIO_ReadOutputDataBit The meaning of function .

LED.h

Definition of header file and 51 There is no difference :

Code up ：

#ifndef __LED_H__
#define __LED_H__

void LED_Init(void);
void LED1_ON(void);
void LED1_OFF(void);
void LED2_ON(void);
void LED2_OFF(void);
void LED1_turn(void);
void LED2_turn(void);

#endif

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3. Write key part

key.c

Code up ：
 

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



// Key initialization 
void key_Init()
{
	 	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB,ENABLE);
		GPIO_InitTypeDef GPIO_InitStrucTure;
		GPIO_InitStrucTure.GPIO_Mode =  GPIO_Mode_IPU; // Key , Pull up with 
		GPIO_InitStrucTure.GPIO_Pin = GPIO_Pin_1 | GPIO_Pin_11;
		GPIO_InitStrucTure.GPIO_Speed = GPIO_Speed_50MHz;
		GPIO_Init(GPIOB,&GPIO_InitStrucTure);
		
}

// Key detection  
uint8_t key_GetNum(void)
{
	uint8_t key_Num = 0;
	if(GPIO_ReadInputDataBit(GPIOB,GPIO_Pin_1)==0)  // Press the key 
	{
		Delay_ms(20); // Press the key to shake off 
		while(GPIO_ReadInputDataBit(GPIOB,GPIO_Pin_1)==0);// Test release , Because there is no action until the key is pressed and the hand is released 
		Delay_ms(20); // Press the key to shake off 
		key_Num = 1;
	}
		if(GPIO_ReadInputDataBit(GPIOB,GPIO_Pin_11)==0)
	{
		Delay_ms(20); // Press the key to shake off 
		while(GPIO_ReadInputDataBit(GPIOB,GPIO_Pin_11)==0);
		Delay_ms(20); // Press the key to shake off 
		key_Num = 2;
	}	
	
		return key_Num;
	
	
}

Because it involves two buttons , So when writing key initialization , Structure sub item GPIO_PIN The value of is GPIO_Pin_1 | GPIO_Pin_11, Adopt the mode of pull-up input , The key part is also similar to 51 Also pay attention to the problem of key shaking elimination , In this way, the key part is finished .

Last , Call in the main function .

main.c

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

uint8_t key_Num;

int main(void)
{
	
	LED_Init();
	key_Init();
	while(1)
	{
		key_Num=key_GetNum();
		if(key_Num==1)
		{
			LED1_turn();
		}
		if(key_Num==2)
		{
			LED2_turn();
		}
		
	}
}