Microcontroller Lcd display with keypad

[lgy]

Hi i need help on my Lcd and keypad . I have a 4X4 keypad and a lcd .

 

Please help as Im struggling on the codes .Im able to display the keys to the lcd screen but i wanna let the user key in 4 digit and an alphabet ( the alphabet will act as a Enter ) and it will store the “passcode”.

 

this is my code for now .

 

#include <p18F4550.h>

#include <delays.h>

#include “lcd.h” // Include file is located in the project directory

 

// Include this when using Bootloader Program ================================

#pragma udata

 

extern void _startup (void);        // See c018i.c in your C18 compiler dir

#pragma code _RESET_INTERRUPT_VECTOR = 0x000800

void _reset (void)

{

    _asm goto _startup _endasm

}

#pragma code

 

#pragma code _HIGH_INTERRUPT_VECTOR = 0x000808

void _high_ISR (void)

{

    ;

}

 

#pragma code _LOW_INTERRUPT_VECTOR = 0x000818

void _low_ISR (void)

{

    ;

}

#pragma code

 

#pragma code

 

// additional codes ends here ===============================================================

 

// Your program declarations start here:====

 

#define LCD_RS PORTDbits.RD6    //  Register Select on LCD

#define LCD_EN PORTDbits.RD4    //  Enable on LCD controller

#define LCD_WR PORTDbits.RD5    //  Write on LCD controller

 

#define KEY_DA PORTBbits.RB5   //  74922 DA output

#define KEY_PORT PORTB // RB3 to RB0 has keypad data

 

unsigned char key,msgindex,outchar,lcdindex;

char Message1 [ ] = “Enter PIN number :  “;  // Defining a 20 char string

 

//— Function for writing a command byte to the LCD in 4 bit mode

---

 

void lcd_write_cmd(signed char cmd)

{

    unsigned char temp2;

    LCD_RS = 0; // Select LCD for command mode

    Delay10TCYx(4); // 40us delay for LCD to settle down

    temp2 = cmd;

    temp2 = temp2 >> 4; // Output upper 4 bits, by shifting out lower 4 bits

    PORTD = temp2 & 0x0F; // Output to PORTD which is connected to LCD

 

    Delay1KTCYx(10); // 10ms -Delay at least 1 ms before strobing

    lcd_strobe();

 

Delay1KTCYx(10); // 10ms – Delay at least 1 ms after strobing

 

    temp2 = cmd; // Re-initialise temp2

    PORTD = temp2 & 0x0F; // Mask out upper 4 bits

 

    Delay1KTCYx(10); // 10ms – Delay at least 1 ms before strobing

    lcd_strobe();

 

    Delay1KTCYx(10); // 10ms – Delay at least 1 ms before strobing

 

}

 

 

//—- Function to write a character data to the LCD

---

 

void lcd_write_data(char data)

{

    char temp1;

 

    LCD_RS = 1; // Select LCD for data mode

    Delay10TCYx(4); // 40us delay for LCD to settle down

 

    temp1 = data;

    temp1 = temp1 >> 4;

    PORTD = temp1 & 0x0F;

    Delay1KTCYx(10);

LCD_RS = 1;

    Delay1KTCYx(10); //_-_ strobe data in

 

    lcd_strobe();

    Delay1KTCYx(10);

 

    temp1 = data;

    PORTD = temp1 & 0x0F;

Delay1KTCYx(10);

    LCD_RS = 1;

    Delay1KTCYx(10); //_-_ strobe data in

 

    lcd_strobe();

    Delay1KTCYx(10);

 

}

 

 

//– Function to generate the strobe signal for command and character

---

 

void lcd_strobe(void) // Generate the E pulse

{

 

    LCD_EN = 1; // E = 0

    Delay1KTCYx(1); // 1ms delay for LCD_EN to settle

      LCD_EN = 0; // E = 1

    Delay1KTCYx(1); // 1ms delay for LCD_EN to settle

 

}

 

 

 

//—- Function to initialise LCD module

---

void lcd_init(void)

{

    TRISD = 0x00;

    PORTD = 0x00; // PORTD is connected to LCD data pin

    LCD_EN = 0;

    LCD_RS = 0; // Select LCD for command mode

    LCD_WR = 0; // Select LCD for write mode

 

    Delay10KTCYx(250); // Delay a total of 1 s for LCD module to

    Delay10KTCYx(250); //

    Delay10KTCYx(250); //

    Delay10KTCYx(250); // finish its own internal initialisation

 

    /* The data sheets warn that the LCD module may fail to initialise properly when

       power is first applied. This is particularly likely if the Vdd

       supply does not rise to its correct operating voltage quickly enough.

 

       It is recommended that after power is applied, a command sequence of

       3 bytes of 3xh be sent to the module. This will ensure that the module is in

       8-bit mode and is properly initialised. Following this, the LCD module can be

       switched to 4-bit mode.

    */

 

    lcd_write_cmd(0x33);

    lcd_write_cmd(0x32);

 

    lcd_write_cmd(0x28); // 001010xx ?Function Set instruction

    // DL=0 :4-bit interface,N=1 :2 lines,F=0 :5×7 dots

 

    lcd_write_cmd(0x0E); // 00001110 ?Display On/Off Control instruction

    // D=1 :Display on,C=1 :Cursor on,B=0 :Cursor Blink on

 

    lcd_write_cmd(0x06); // 00000110 ?Entry Mode Set instruction

    // I/D=1 :Increment Cursor position

    // S=0 : No display shift

 

    lcd_write_cmd(0x01); // 00000001 Clear Display instruction

 

    Delay10KTCYx(20); // 20 ms delay

 

}

 

//

---

Function to obtained wait for key press and returns its ASCII value

 

char getkey(void)

{ char keycode;

    const unsigned char lookup[] = “123F456E789DA0BC “;

 

    while (KEY_DA==0); //wait for key to be pressed

    keycode=KEY_PORT &0x0F; //read from encoder at portB,mask upper 4 bits

 

    while (KEY_DA==1); //wait for key to be released

    return(lookup[keycode]); //convert keycode to its ascii value for LCD

}

 

// —- Main Program

---

 

void main(void)

{

// Do not remove these as well=============

ADCON1 = 0x0F; // Configure PORTA to be digital I/O

CMCON = 0x07;

// ========================================

// Your MAIN program Starts here: =========

 

lcd_init(); // Initialise LCD module

 

LCD_RS = 1; // Select LCD for character data mode

Delay1KTCYx(1); // 1 ms delay

 

while(1)

{

lcd_write_cmd(0x80); // Move cursor to line 1 position 1

 

for (msgindex = 0; msgindex < 20; msgindex++) //for 20 char LCD module

{

outchar = Message1[msgindex];

 

lcd_write_data(outchar); // write character data to LCD

}

 

  

  lcd_write_cmd(0xC0); // Move cursor to line 2 position 1

 

for (lcdindex = 0; lcdindex < 20; lcdindex++) //for 20 number

    { 

key=getkey(); // waits and get an ascii key number when pressed

 

       lcd_write_data(key); //display on LCD

 

    }

 

lcd_write_cmd(0x01); // 00000001 Clear Display instruction

 

Delay1KTCYx(250); // Delay for 1 s before proceeding to repeat

Delay1KTCYx(250);

Delay1KTCYx(250);

Delay1KTCYx(250);

 

}

}

 

 

Im sorry if its too long and messy as this is my first post in this forum . Your help will be much appreciated.

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