I need help with interfacing LCD module with 8051

Question

Hello every one,
I've been working the MCU and LCD module in  vesrion 10.
I cant  to make it work. Your help will be really appriciated. we have purchased multisim at our school i need to prepare myself
to offer it. I seed to be stuck with a few things using the 8051, and LCD is one of them. If i get this right, then i will move to the next.
here is a code i got from another forum. I have tried different codes, but they all seem not to work. im not sure if it's the code or the design or some bugs with these modules. your help is most welcome.
here is the code:
#include <htc.h>
#include <stdio.h>
#define LCD_data P2
#define LCD_D7   P27
#define LCD_rs   P10
#define LCD_rw   P11
#define LCD_en   P12
/*static volatile unsigned char LCD_data @ 0xA0;
static volatile bit LCD_D7   @ 0xA7;
static volatile bit LCD_rs   @ 0x90;
static volatile bit LCD_rw   @ 0x91;
static volatile bit LCD_en   @ 0x92;*/
void LCD_init();
void LCD_busy();
void LCD_command(unsigned char );
void LCD_senddata(unsigned char );
void LCD_sendstring(unsigned char *);
void main()
    unsigned char msg[] = "HELLO WORLD";
     LCD_init();
     LCD_command(0x80);
     LCD_sendstring(msg);
    while(1);  
void LCD_init()
     LCD_data = 0x38;     //Function set: 2 Line, 8-bit, 5x7 dots
     LCD_rs   = 0;        //Selected command register
     LCD_rw   = 0;        //We are writing in data register
     LCD_en   = 1;        //Enable H->L
     LCD_en   = 0;
     LCD_busy();          //Wait for LCD to process the command
     LCD_data = 0x0D;     //Display on, Curson blinking command
     LCD_rs   = 0;        //Selected command register
     LCD_rw   = 0;        //We are writing in data register
     LCD_en   = 1;        //Enable H->L
     LCD_en   = 0;
     LCD_busy();          //Wait for LCD to process the command
     LCD_data = 0x01;     //Clear LCD
     LCD_rs   = 0;        //Selected command register
     LCD_rw   = 0;        //We are writing in data register
     LCD_en   = 1;        //Enable H->L
     LCD_en   = 0;
     LCD_busy();          //Wait for LCD to process the command
     LCD_data = 0x06;     //Entry mode, auto increment with no shift
     LCD_rs   = 0;        //Selected command register
     LCD_rw   = 0;        //We are writing in data register
     LCD_en   = 1;        //Enable H->L
     LCD_busy();
void LCD_busy()
     LCD_D7   = 1;           //Make D7th bit of LCD as i/p
     LCD_en   = 1;           //Make port pin as o/p
     LCD_rs   = 0;           //Selected command register
     LCD_rw   = 1;           //We are reading
     while(LCD_D7)
    {          //read busy flag again and again till it becomes 0
           LCD_en   = 0;     //Enable H->L
           LCD_en   = 1;
/*unsigned char i,j;
3+69
         for(i=0;i<50;i++)        //A simple for loop for delay
            for(j=0;j<255;j++);*/
void LCD_command(unsigned char var)
     LCD_data = var;      //Function set: 2 Line, 8-bit, 5x7 dots
     LCD_rs   = 0;        //Selected command register
     LCD_rw   = 0;        //We are writing in instruction register
     LCD_en   = 1;        //Enable H->L
     LCD_en   = 0;
     LCD_busy();          //Wait for LCD to process the command
/* Using the above function is really simple
 var will carry the command for LCD
 e.g.
 LCD_command(0x01);*/
void LCD_senddata(unsigned char var)
     LCD_data = var;      //Function set: 2 Line, 8-bit, 5x7 dots
     LCD_rs   = 1;        //Selected data register
     LCD_rw   = 0;        //We are writing
     LCD_en   = 1;        //Enable H->L
     LCD_en   = 0;
     LCD_busy();          //Wait for LCD to process the command
/* Using the above function is really simple
 we will pass the character to display as argument to function
 e.g.
 LCD_senddata('A');*/
void LCD_sendstring(unsigned char *var)
     while(*var)              //till string ends
       LCD_senddata(*var++);  //send characters one by one
/* Using the above function is really simple
// we will pass the string directly to the function
// e.g.
// LCD_sendstring("LCD Tutorial");*/ 
Ihave also attached the schematic. 
Tahnx in advance 
Attachments:
schem.JPG ‏37 KB

Answer 1

please tell us what model of computer you have, and what RAM it has in it before you started, and what the detaails of the new RAM you are trying to put in are.
It might be that your new RAM is the wrong type, or that that is not right for your particular PC, or even simply that it has not gone in properly. Trying taking it out, booting up yto see if everything iis OK (at which time you might try installing CPU-Z, running that, and posting some screenshots), and reinserting the new memory card.  They can be a be a bit awkward to insert and a bit stiff, but don not apply too much force, look to see if it has gone it evenly and the same at both ends, can you operate the latches at either end ?
Woodwood
30.October.2011