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You are here: Home / Topics / some questions about the project “Electronic code lock with user defined password using 8051 microcontroller (AT89C51)”

some questions about the project “Electronic code lock with user defined password using 8051 microcontroller (AT89C51)”

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Electronics › Electronics › some questions about the project “Electronic code lock with user defined password using 8051 microcontroller (AT89C51)”

  • This topic has 25 replies, 22 voices, and was last updated 11 years, 1 month ago by asfandyar.
Viewing 15 posts - 1 through 15 (of 26 total)
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    Posts
  • May 2, 2011 at 4:01 pm #900
    vijay
    Participant

    in the picture,some extra resistors are attached to the connection between the keypad and the ic.are these necessary?

    May 6, 2011 at 10:01 am #6095
    dagakshay
    Participant

    nopes not necessary but better if you connect…

    May 10, 2011 at 6:49 pm #6142
    SaLMAN Ahmed Khan
    Participant

    if the keypad is connected to PORT 0 OF 8051 then you must need to connect these resistors as they work as pull up ……

     

    but you can use the other port to interface keypad .

    May 13, 2011 at 12:28 am #6178
    romel emperado
    Participant

    post here the link of that project.. I will try if i can explain the fuction of that resistor.. okay?

    May 14, 2011 at 3:37 am #6194
    dagakshay
    Participant

    hello romel,

    here is the link

    http://www.engineersgarage.com/microcontroller/8051projects/electronic-code-lock-with-password-using-at89c51-circuit

    May 16, 2011 at 1:54 am #6206
    romel emperado
    Participant

    that resistors are use to limit the current flowing the I/O pins when button is pressed..  but if you wish you can remove that and still it will work..

    October 8, 2011 at 11:42 am #6688
    Qaisar
    Participant

    wysiwyg_imageupload:2860:

    November 21, 2011 at 2:47 pm #6862
    Hercules
    Participant

    The project Electronic code lock with user defined password using 8051 microcontroller (AT89C51) has 26 errors in code.Please provide me correct code.I need it  very urgently

    November 21, 2011 at 6:19 pm #6863
    Qaisar
    Participant

    hi 

     that code dosent have any problem at all. i dont know why you have 26 errors…

    which compiler you are using ?

     

    December 2, 2011 at 9:33 pm #6905
    Mike Blanchard
    Participant

    Quick question about th eelectronic lock using the 8051 chip…

     

     Can I program it to light a LED or ring a buzzer if the wrong code is entered 3 times?  I can see applying a relay that will be activated upon the lock code and deactivated for the unlock code, but I’d also like a buzzer to go off or an LED light if the wrong code is entered 3 times instead of it simply stating that “wrong code entered” on the LCD screen.

     

     thank you!

      Mike B

    December 4, 2011 at 10:58 am #6906
    Dexter
    Participant

    hai friends i have made the project , eletronic code lock

    with this we can switch on and off 8 led (relay)

    i have used keil and Proteus 7 Professional

    it works well

    wysiwyg_imageupload:3309:

    December 4, 2011 at 5:16 pm #6908
    FARRUKH
    Participant

    http://www.engineersgarage.com/microcontroller/8051projects/electronic-code-lock-with-password-using-at89c51-circuit

     

    This circuit is not working.I can’t enter any digit because it is doing the job itself…

    January 14, 2012 at 11:38 am #7033
    amit
    Participant

    is this project really work practically???

     

     

    http://www.engineersgarage.com/microcontroller/8051projects/electronic-code-lock-with-password-using-at89c51-circuit

    February 3, 2012 at 7:18 am #7104
    jayesh
    Participant

    Here the variable-Resistrer is for vary the brightness of lcd for saving the energy..

    February 10, 2012 at 11:53 pm #7148
    Dexter
    Participant

    this may be useful

     

    #include <reg51.H>          //……………….headder file
    #include <stdio.h>          //……………….headder file
    #include <string.h>     //……………….headder file

    /*………………PIN CONNECTIONS…………………………………………………………….*/

    #define LCD_PORT P2        //……………….lcd data port to be connected
    #define    port0 P0        //……………….Port for keypad connection
    #define REL_PORT P1        //……………….relay connection port
    sbit    LED2=P3^3;        //……………….LCD PIN Connection
    sbit    EN=P3^7;        //……………….enable pin for LCD
    sbit    RW=P3^6;        //……………….write pin for LCD         
    sbit    RS=P3^5;        //……………….register select pin of LCD

    /*………………..Declarations ……………………………………………*/

    //………………..DELAYS………………………//

    void Delay_in_ms(unsigned char);    //……………..milli second delay is to be specifide
    void Delay_in_10ms(unsigned char);    //……………..10 * number of milli sec
    void Delay_in_1s(unsigned char);    //……………..number of sec

    //………………….LCD………………………//

    void lcd_init        (void);                    //………routine to initialise LCD
    void write_in        (unsigned char );        //………writes data in to LCD as instruction
    void write            (unsigned char );        //………writes one byte into LCD
    void printLcd        (unsigned char *);        //………prints a line on LCD
    void printLcd2        (unsigned char *);        //………prints a line on LCD
    void clear_display    (void);                    //………clears LCD screen
    void set_add        (unsigned char );        //………sets the display position
    void write_data        (unsigned char );        //………writes one byte into LCD as data

    //………………..relay………………………//

    void RELAY_GO(unsigned char ,unsigned char );    //…..selection of relay through keybord
    void relay_set(unsigned char);                    //…..selected relay ON or OFF            
    #define RON  1         //……………………………relay pin on state
    #define ROFF 0         //……………………………relay pin off state
    sbit RELAY1 = P1^0;    //……………………………relay one
    sbit RELAY2 = P1^1;    //……………………………relay two
    sbit RELAY3 = P1^2;    //……………………………relay three
    sbit RELAY4 = P1^3;    //……………………………relay four
    sbit RELAY5 = P1^4;    //……………………………relay five
    sbit RELAY6 = P1^5;    //……………………………relay six
    sbit RELAY7 = P1^6;    //……………………………relay seven
    sbit RELAY8 = P1^7;    //……………………………relay eight

    /* ………………password functions…………………*/

    char  key0 = ‘*’;            //……………………..MASK key press
    unsigned char key1;            //……………………..1 key press
    unsigned char key2;            //……………………..2 key press
    unsigned char key3;            //……………………..3 key press
    unsigned char key4;            //……………………..4 key press
    unsigned char key5;            //……………………..5 key press
    unsigned char key6;            //……………………..6 key press

    void relese_go(unsigned char, unsigned char, unsigned char, unsigned char, unsigned char);
    void lock_go(unsigned char , unsigned char , unsigned char , unsigned char , unsigned char , unsigned char );

    /*…………………….4X4 keybord……………………*/

    // key select functions

    void select(void);                //……………………..selection of relay
    void locker();                    //……………………..lockre rootine
    void menu_1(void);                //……………………..function choose
    void menu_2(void);                //……………………..function choose
    void stop(void);                //……………………..system halt
    void sleep(void);                //……………………..system standby
    unsigned char keyS;                //……………………..selected key
    unsigned char keypad(void);        //……………………..key input
    void call_for_column(void);        //……………………..key routien work
    unsigned char getport0,col,row;    //…………………..key routien work
    unsigned char keypad_value;        //……………………..value of key
    unsigned char key[4][4] = { ‘1’,’2′,’3′,’R’,
                                ‘4’,’5′,’6′,’P’,
                                ‘7’,’8′,’9′,’L’,
                                ‘*’,’0′,’#’,’S’};

    //………………progam starts………………………………….//
    void main()
    {
        REL_PORT=0x00;                        //………initialising relay port
        lcd_init();                            //………initialising lcd port
        lock= ROFF;    
        clear_display();                    //………clear th display
            printLcd(”  Dexter8051  “);        //……..FOR PRINTING IN FIRST LINE
            printLcd2(” WELCOMES YOU    “);    //……..FOR PRINTING IN SECAND LINe
            Delay_in_1s(2);*/

            locker();
        }    
    }

    //……………..menu 1 select………………//

    void menu_1(void )
        {
        clear_display();
        printLcd (“RELAY :press R “);
        keyS= keypad();
        if(keyS==’R’)
                    {
                    select();
                    }
        else
            {
            clear_display();
            printLcd(“WRONG INPUT”);
            Delay_in_1s(1);
            menu_1();
            }
        }

    //…………on off select function………….//

    void select(void)
    {
        clear_display();
        printLcd(“Enter relay no:”);
        key1=keypad();
        write_data(key1);
        Delay_in_10ms(2);
        set_add(0xc0);
        printLcd(“PRESS # ON * OFF”);
        Delay_in_1s(1);
        key2=keypad();
        Delay_in_10ms(2);
        clear_display();
        RELAY_GO(key1,key2);
        Delay_in_1s(1);
        menu_1();
    }

    //…………………..relay to be on off select rooine…………//

    void RELAY_GO(unsigned char a,unsigned char b)
    {
        {
        if(a==’1’& b==’#’)
                    {
                    relay_set(1);// RELAY 1 on //calling relay_set function
                    }
    else if(a==’1’& b==’*’)
                    {
                    relay_set(2);// RELAY 1 off //calling relay_set function
                    }
    else if(a==’2’& b==’#’)
                    {
                    relay_set(3);// RELAY 2 on //calling relay_set function
                    }
    else if(a==’2’& b==’*’)
                    {
                    relay_set(4);// RELAY 2 off //calling relay_set function
                    }
    else if(a==’3’& b==’#’)
                    {
                    relay_set(5);// RELAY 3 on //calling relay_set function
                    }
    else if(a==’3’& b==’*’)
                    {
                    relay_set(6);// RELAY 3 off //calling relay_set function
                    }
    else if(a==’4’& b==’#’)
                    {
                    relay_set(7);// RELAY 4 on //calling relay_set function
                    }
    else if(a==’4’& b==’*’)
                    {
                    relay_set(8);// RELAY 4 off //calling relay_set function
                    }
    else if(a==’5’& b==’#’)
                    {
                    relay_set(9);// RELAY 5 on //calling relay_set function
                    }
    else if(a==’5’&b==’*’)
                    {
                    relay_set(10);// RELAY 5 off //calling relay_set function
                    }
    else if(a==’6’&b==’#’)
                    {
                    relay_set(11);// RELAY 6 on //calling relay_set function
                    }
    else if(a==’6’& b==’*’)
                    {
                    relay_set(12);// RELAY 6 off //calling relay_set function
                    }
    else if(a==’7’& b==’#’)
                    {
                    relay_set(13);// RELAY 7 on //calling relay_set function
                    }
    else if(a==’7’& b==’*’)
                    {
                    relay_set(14);// RELAY 7 off //calling relay_set function
                    }
    else if(a==’8’& b==’#’)
                    {
                    relay_set(15);// RELAY 8 on //calling relay_set function
                    }
    else if(a==’8′ & b==’*’)
                    {
                    relay_set(16);// RELAY 8 off //calling relay_set function
                    }
        else
                {
                  clear_display();
                printLcd(“WRONG INPUT KEY”);
                }
            }
    }

    //…………………LCD Routines…………………..//

    //routine to initialise the lcd
    void lcd_init(void)
    {        
        write_in(0x38);          //to make lcd
        Delay_in_ms(1);
        write_in(0x0f);          //to make lcd to select 5×7 matrix display
        Delay_in_ms(1);
         write_in(0x01);          //to make lcd to clear the display
        Delay_in_ms(1);
        write_in(0x80);          //to make lcd cursor to bigining of first line
        Delay_in_ms(1);
    }
    //routine to write an instruction to LCD
    void write_in(unsigned char ch)
    {
        RS=0;                //rs =0 for instr
        RW=0;            
        write(ch);            //routine to transfer 8 bits to LCD
    }
    //routine to transfer 8 bits to LCD module
    void write(unsigned char ch)
    {
        LCD_PORT = ch;        //preserves the old value of port
        EN = 1;                //enable pin high
        Delay_in_ms(1);
        EN = 0;                //enable = 0
    }
    //clears the entire display area of LCD
    void clear_display(void)
    {
        write_in(0x01);            //clears the lcd display
        write_in(0x80);            //write code to blink at first line first coloum
    }
    //printing rootin
    //routine to display the value in the accumulator in LCD
    //routine to display a string on first line
    //this routine will display a string stored at address pointed by dptr
    void printLcd(unsigned char *str)
    {
        unsigned char len,i;
        len = strlen(str);
        set_add(0x80);                //sets display position in first line
        for(i=0;i<len;i++)
        {
        write_data(*str);        //displays the character on LCD
        str++;
        }
    }
    void printLcd2(unsigned char *str)
    {
        unsigned char len,i;
        len = strlen(str);
        set_add(0xc0);        //sets display position in second  line
        
        for(i=0;i<len;i++)
            {
                write_data(*str);    //displays the character on LCD
                str++;
            }
    }
    //routine to set the display position
    void set_add(unsigned char ch)
    {
        write_in(ch);        //writes it as instruction
    }
    //routine to write a data to LCD
    void write_data(unsigned char ch)
    {
        RS = 1;
        RW=0;            
        write(ch);            //……….transfers 8 bits to lcd module    
    }
    //ms delay in milli secand
    void Delay_in_1s(unsigned char ms)//……………..number of secands
    {
        int t;
        t=ms;
        {
        unsigned int i;
        for(i=0;i<t;i++)
        {
        Delay_in_10ms(10);
        }
        }
    }    
    void Delay_in_10ms(unsigned char ms)//……………..milli sec * 10
    {
        int t;
        t=ms;
        {
        unsigned int i;
        for(i=0;i<t;i++)
        {
        Delay_in_ms(100);
        }
        }
    }    
    void Delay_in_ms(unsigned char ms)//……………….milli sec
    {
        int t;
        t= ms;
        {
        unsigned int i,j;
        for(i=0;i<t;i++)
        for(j=0;j<120;j++);
        }
    }
    //…………..key board processes……………..//

    unsigned char keypad()
    {
        do
        {
            do
            {
            port0 = 0x0f;
            getport0 = port0;
            getport0 = getport0 & 0x0f;
            }while(getport0 != 0x0f);
        
        getport0 = port0;
        getport0 = getport0 & 0x0f;
        }while(getport0 !=0x0f);
        
        while(1)
        {
                port0 = 0xef;
                getport0 = port0;
                getport0 = getport0 & 0x0f;
                if(getport0 != 0x0f)
                {
                    row = 0;
                    call_for_column();

                    break;
                }
                port0 = 0xdf;
                getport0 = port0;
                getport0 = getport0 & 0x0f;
                if(getport0 != 0x0f)
                {
                    row = 1;
                    call_for_column();
                    break;
                }
               
                port0 = 0xbf;
                getport0 = port0;
                getport0 = getport0 & 0x0f;
                if(getport0 != 0x0f)
                {
                    row = 2;
                    call_for_column();
                    break;
                }
               
                port0 = 0x7f;
                getport0 = port0;
                getport0 = getport0 & 0x0f;
                if(getport0 != 0x0f)
                {
                    row = 3;
                    call_for_column();
                    break;
                }
        }
    keypad_value = key[row][col];
    return keypad_value;
    }
    void call_for_column()
    {
        while(1)
        {
            if(getport0 == 0x07)
            {
                col = 0;
               
                Delay_in_10ms(3);
               
                break;
            }
            else if(getport0 == 0x0b)
            {
                col = 1;
               
                Delay_in_10ms(3);
               
                break;
            }
            else if(getport0 == 0x0d)
            {
                col = 2;
               
                Delay_in_10ms(3);
               
                break;
            }
            else if(getport0 == 0x0e)
            {
                col = 3;
               
                Delay_in_10ms(3);
               
                break;
            }
        }
    }

    //……….relay switching processes……………..//

    void relay_set(unsigned char relay)
    {
        int x;
        x= relay;
         switch (x)
        {
        case 1:            //………………..RELAY 1 OFF
       RELAY1= RON;
           printLcd(“RELAY 1 ON “);
        break;
        case 2:            //………………..RELAY 1 0N
       RELAY1= ROFF;
        printLcd(“RELAY 1 OFF”);
        break;
        case 3:            //………………..RELAY 2 OFF
       RELAY2= RON;
       printLcd(“RELAY 2 ON “);
        break;
        case 4:            //………………..RELAY 2 0N
       RELAY2= ROFF;
       printLcd(“RELAY 2 OFF”);
        break;
        case 5:            //…………………RELAY 3 OFF
       RELAY3= RON;
       printLcd(“RELAY 3 ON “);
        break;
        case 6:            //………………..RELAY 3 0N
       RELAY3= ROFF;
       printLcd(“RELAY 3 OFF”);
        break;
        case 7:            //………………..RELAY 4 OFF
       RELAY4= RON;
       printLcd(“RELAY 4 ON “);
        break;
        case 8:            //………………..RELAY 4 0N
       RELAY4= ROFF;
       printLcd(“RELAY 4 OFF”);
        break;
        case 9:            //………………..RELAY 5 OFF
       RELAY5= RON;
       printLcd(“RELAY 5 ON “);
        break;
        case 10:            //……………….RELAY 5 0N
       RELAY5= ROFF;
       printLcd(“RELAY 5 OFF”);
        break;
        case 11:            //……………….RELAY 6 OFF
       RELAY6= RON;
       printLcd(“RELAY 6 ON “);
        break;
        case 12:            //………………..RELAY 6 0N
       RELAY6= ROFF;
       printLcd(“RELAY 6 OFF”);
        break;
        case 13:            //………………..RELAY 7 OFF
       RELAY7= RON;
       printLcd(“RELAY 7 ON “);
        break;
        case 14:            //………………..RELAY 7 0N
       RELAY7= ROFF;
       printLcd(“RELAY 7 OFF”);
        break;
        case 15:            //………………..RELAY 8 0FF
       RELAY8= RON;
       printLcd(“RELAY 8 ON “);
        break;
        case 16:            //………………..RELAY 8 0N
       RELAY8= ROFF;
       printLcd(“RELAY 8 OFF”);
        break;
        }
    }

    //…………..locker password code…………….//

    void locker(void)
    {    
        clear_display();
        printLcd(“ENTER PASSWORD”);
        set_add(0xc0);
        key1=keypad();
        write_data(key0);
        key2=keypad();
        write_data(key0);
        key3=keypad();
        write_data(key0);
        key4=keypad();
        write_data(key0);
        key5=keypad();
        write_data(key0);
        key6=keypad();
        write_data(key0);
        lock_go(key1,key2,key3,key4,key5,key6);
    }
    //……………………..lock code ………………………//

    void lock_go(unsigned char a, unsigned char b, unsigned char c, unsigned char d, unsigned char e, unsigned char f)
    {
        if(a==’1′ & b==’2′ & c==’3′ & d==’4′ & e==’5′ & f==’6′)
                {
                clear_display();
                printLcd(“CORRECT PASSWORD”);
                printLcd2(“LOCK IS OPEN”);
                Delay_in_1s(1);
                menu_1();
                }
        else
            {

            locker();
            }
    }

    wysiwyg_imageupload:3747:

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