[SOLVED] lcd 4 bit error .. trying to interfcing with 8051 in single port

[FvM]

For lcd_data()

LCDPORT = c & 0xf0 | 0x4;

There's no need to set RS before DB bits, by the way.

 

[thannara123]

But sir some thing wrong not working

    #include <REGX51.H>
    #define LCDPORT P2
    sbit RS = LCDPORT ^ 2;
    sbit E = LCDPORT ^ 3;
     
    void delay(unsigned int itime)
    {
    unsigned int i, j;
    for (i = 0; i < itime; i++)
    for (j = 0; j < 1275; j++);
    }
     
     
     
    void latch(void)
    {
    E = 1;
    delay(10);
    E = 0;
    }
     
    void lcd_cmd(unsigned char c)
    {
    RS = 0;
    delay(1);
    LCDPORT = c & 0xf0;
    latch();
    delay(1);
    LCDPORT = (c << 4);
    latch();
    }
     
    void lcd_data(unsigned char c)
    {
    //RS =1;
    delay(1);
    LCDPORT = c & 0xf0 | 0x4;
    delay(1);
    latch();
     
    LCDPORT = (c << 4) | 0x4;;
    latch();
    }
     
    void lcd_init()
    {
    delay(50);
    lcd_cmd(0x30);
    delay(20);
    lcd_cmd(0x30);
    delay(4);
    lcd_cmd(0x30);
    delay(4);
    lcd_cmd(0x28); // Function set (4-bit interface, 2 lines, 5*7Pixels)
    lcd_cmd(0x28); // Function set (4-bit interface, 2 lines, 5*7Pixels)
    lcd_cmd(0x0c); // Make cursorinvisible
    lcd_cmd(0x6); // Set entry Mode(auto increment of cursor)
    }
     
     
     
     
     
    void main()
    {
    P2 = 0x00;
    lcd_init();
    lcd_cmd(0x80);
    lcd_data(1); // just send "1" to lcd to display ;
    P3 = 0xf0;
    while (1);
    }

- - - Updated - - -

thanks working sir really help full
changed as
lcd_data('2');

thanks to all

 

[tushki7]

Greetings,
Sorry thannara for late reply but I am so busy with my project, here is a working 4 bit program but the read, write enable pins are at different ports. So you have to edit it according to your needs.

#include<reg52.h>
#define ldata P1          //16x2 lcd data pins to port p1
sbit en = P2^2;              
//sbit busy = P1^7;          //remove comment tags if lcdready() function is used
sbit rs = P2^0;
sbit rw = P2^1;
void lcdcmd(unsigned char l);
void lcddata(unsigned char l);
void MSDelay(unsigned int t);
//void lcdready();
void callmsg();
void callme();
void main()
{
 while(1)
 {
 lcdcmd(0x28);
 lcdcmd(0x0C);
 lcdcmd(0x01);
 lcdcmd(0x06);
 lcdcmd(0x0C0);              // force cursor to begin with 2nd row
// lcddata('1');          // display single numeric or character
 callmsg();                  // to display string 
 MSDelay(255);
 MSDelay(255);
 MSDelay(255);
 MSDelay(255);
 //lcdcmd(0x01);
 //lcdcmd(0x06);
 lcdcmd(0x80);              // force cursor to begin with 1st row
 callme();
 MSDelay(255);
 MSDelay(255);
 }
 }
 void callmsg()
 { 
 unsigned char message[] = "www.edaboard.com";
 unsigned char z,l;
    
for(z=0;z<16;z++)
 {
  l = message[z];
  lcddata(l);
 // MSDelay(100);
 }
}
void callme()
{
 unsigned char message[] = "Happy New Year";
 unsigned char z,l;
 

for(z=0;z<15;z++)
 {
  l = message[z];
  lcddata(l);
//  MSDelay(100);
 }
}

void lcdcmd(unsigned char l)
 { 

//  lcdready();
 ldata = l & 0xf0;
 rs = 0;
 rw = 0;
 en = 1;
  MSDelay(1);
 en = 0; 
//  lcdready();
 l = (l << 4);
 ldata = l;
 rs = 0;
 rw = 0;
 en = 1;
 MSDelay(1);
 en = 0;  
 return;
 }

 void lcddata(unsigned char l)
 {       
 //    lcdready();
 ldata = l & 0xf0;
 rs = 1;
 rw = 0;
 en = 1;
 MSDelay(1);
 en = 0; 
//lcdready();
 l = (l << 4);
 ldata = l;
 rs = 1;
 rw = 0;
 en = 1;
  MSDelay(1);
 en = 0;
return;
 }
/*
 void lcdready()
 {
  busy = 1;
  rs = 0;
  rw = 1;
  while(busy==1)
  {
   
   en = 0;
   MSDelay(1);
   en = 1;
  
  }
  
  return;
 
 } 
          */
  void MSDelay(unsigned int t)
 {
  
  unsigned int i,j;
  for(i=0;i<t;i++)
   {
    for(j=0;j<255;j++)
       {}
   }
 }

Good Luck