Published April 14, 2020

Digital Lock Using ATMEGA32

This project deals on how we can implement a simple digital number lock based embedded system using a 4x4 matrix keypad and ATMEGA32

IntermediateProtip1 hour9,781

Things used in this project

Hardware components

Adafruit RGB Backlight LCD - 16x2

Microchip Atmega32

4x4 matrix keypad

Software apps and online services

Microchip Studio

Proteus 7.7

Story

I developed this project as part of my embedded systems project work.This one is a very cool project and anyone with basic ideas about programming can easily follow my work.

The project basicaaly uses Atmega32 microcontroller.It is an 8-bit atmel AVR series microcontroller.

The input device is a 4x4 matrix keypad. For details regarding its working:https://components101.com/misc/4x4-keypad-module-pinout-configuration-features-datasheet

The output devices include an 16x2 LCD display and a dc motor,

The microcontroller continuously scans the keypad to read the number/character being input by the user. If the value entered matches with the number lock already set, dc motor rotates in one direction.

To lock, number 1 is pressed.If the numlock entered is wrong, the sytem asks the user to re-enter the password again,

Code

digital lock using atmega32

#include<avr/io.h>
#include<avr/eeprom.h>
#include<util/delay.h>

#define lcdport PORTA

#define signal PORTB

#define en PB2

#define rw PB1

#define rs PB0
char password[1];
char lock[0];
char key;

char keycheck();

char scankey();

void lcdcmd(unsigned char cmd);

void lcdint();
unsigned char  lcd_read();

void lcddata(unsigned char data);
void send_a_command(unsigned char command);

void send_a_character(unsigned char character);

void send_a_string(char *string_of_characters);
int main()

{

	DDRA=0xff;

	DDRB=0x0f;

	DDRD=0xf0;

	char key;

	lcdint();
	
    lcddata('E');
	lcddata('N');
	lcddata('T');
	lcddata('E');
	lcddata('R');
	lcddata(' ');
	lcddata('P');
	lcddata('A');
	 lcddata('S');
	 lcddata('S');
	 lcddata('W');
	 lcddata('O');
	 lcddata('R');
	 lcddata('D');
	 lcdcmd(0xC0);       
	 
	 
	

  for(int i=0;i<3;i++)
	{  

		key=scankey();
		
		_delay_ms(1000);
        

		lcddata(key);
		
	   
	   
		
		password[i]=key;
		
        
	}
	lcdcmd(0x01);
	
	if((password[0]=='7')&&(password[1]=='9')&&password[2]=='4')
	  
		{lcddata('C');
		 lcddata('O');
		 lcddata('R');
		 lcddata('R');
		 lcddata('E');
		 lcddata('C');
		 lcddata('T');
		 lcddata(' ');
		 lcddata('P');
		 lcddata('A');
		 lcddata('S');
		 lcddata('S');
		 lcddata('W');
		 lcddata('O');
		 lcddata('R');
		 lcddata('D');
		 DDRC=0xff;
		 PORTC=0x02;
		 _delay_ms(3000);
		 PORTC=0x00;
		 lcdcmd(0x01);
		 lcdcmd(0x80);
		 lcddata('L');
		 lcddata('O');
		 lcddata('C');
		 lcddata('K');
		 lcddata('?');
		 lcddata(' ');
		 lcddata('P');
		 lcddata('R');
		 lcddata('E');
		 lcddata('S');
		 lcddata('S');
		 lcddata(' ');
		 lcddata('1');
		 lcdcmd(0xC0);
		 
		  key=scankey();
		  _delay_ms(1000);
		  

		  lcddata(key);
		  lock[0]=key;
		  if(lock[0]=='1')
		  {DDRC=0xff;
			  PORTC=0x01;
			  _delay_ms(3000);
			  PORTC=0x00;
			  lcdcmd(0x01);
			   lcddata('L');
			   lcddata('O');
			   lcddata('C');
			   lcddata('K');
			   lcddata('E');
			   lcddata('D');
			   _delay_ms(1000);
			  return main();
		  }
		 
	}
	  	
	else
	 lcddata('W');
	 lcddata('R');
	 lcddata('O');
	 lcddata('N');
	 lcddata('G');
	 lcddata(' ');
	 lcddata('P');
	 lcddata('A');
	 lcddata('S');
	 lcddata('S');
	 lcddata('W');
	 lcddata('O');
	 lcddata('R');
	 lcddata('D');
	 
		return main();
	 
	}	



char scankey()

{

	char key='a';

	while(key=='a')

	{

		key=keycheck();
        
       
	}

	return key;
	

}

char keycheck()

{

	PORTD=0b11101111;

	_delay_ms(10);

	if((PIND&0b00000001)==0)

	{
      
		return '7';
		
	}

	if((PIND&0b00000010)==0)

	{

		return '8';

	}

	if((PIND&0b00000100)==0)

	{

		return '9';
		

	}
	if((PIND&0b00001000)==0)
	{
			return 'A';
	}

	PORTD=0b11011111;

	_delay_ms(10);

	if((PIND&0b00000001)==0)

	{

		return '4';

	}

	if((PIND&0b00000010)==0)

	{

		return '5';

	}

	if((PIND&0b00000100)==0)

	{

		return '6';

	}
	if((PIND&0b00001000)==0)
	{
		return 'B';
	}

	PORTD=0b10111111;

	_delay_ms(10);

	if((PIND&0b00000001)==0)

	{

		return '1';

	}

	if((PIND&0b00000010)==0)

	{

		return '2';

	}

	if((PIND&0b00000100)==0)

	{

		return '3';

	}
	if((PIND&0b00001000)==0)
	{
		return'C';
	}

	PORTD=0b01111111;

	_delay_ms(10);

	if((PIND&0b00000001)==0)

	{

		return '*';

	}

	if((PIND&0b00000010)==0)

	{

		return '0';

	}

	if((PIND&0b00000100)==0)

	{

		return '#';

	}
	if((PIND&0b00001000)==0)
	{
		return'D';
	}
	

	return 'a';

}

void lcdint()

{

	lcdcmd(0x38);

	_delay_ms(1);

	lcdcmd(0x01);

	_delay_ms(1);

	lcdcmd(0x0F);

	_delay_ms(100);
   lcdcmd(0x82);
   
   _delay_ms(100);
   lcdcmd(0x89);
   _delay_ms(10);
   lcdcmd(0x01);
   
}



void lcdcmd(unsigned char x)

{

	lcdport=x;

	signal=(0<<rs)|(0<<rw)|(1<<en);

	_delay_ms(1);

	signal=(0<<rs)|(0<<rw)|(0<<en);

	_delay_ms(50);

}

void lcddata(unsigned char data)

{

	lcdport= data;

	signal= (1<<rs)|(0<<rw)|(1<<en);

	_delay_ms(1);

	signal= (1<<rs)|(0<<rw)|(0<<en);

	_delay_ms(50);

}
unsigned char  lcd_read()
{    
	

	signal= (1<<rs)|(1<<rw)|(1<<en);

	_delay_ms(1);

	signal= (1<<rs)|(1<<rw)|(0<<en);

	_delay_ms(50);
	
}

Credits

athul kumar

1 project • 6 followers

Thanks to Mechaterrain.