problem in string display

Haven't you already noticed that by your source code logic, you just can't get your values to print.

If you are interested in printing values, you could at least start to work through the list of problems I specified in an earlier post:

- reversed assigns
- "nested" loops that aren't nested
- void where no void should be
- one string without zero-termination and one string with - how will the print code know how many characters to print?
- interesting mix of arrays and characters
- a function with empty () instead of (void) which might not be what was intended, depending on language selected
- a main that terminates out into the unknown
- a refusal to add comments or label the magic numbers used

how can I get a value there acoording to my source code logic?

you cant, the 'logic' is faulty

if you think ... blah blah blah ...

It was an appropriate response to self-indulgent crassness.

Step one must be to tidy up the listing a bit and fix some of the obvious errors.

#include<reg51.h>
#include<string.h>
#include<stdio.h>

#define lcd_data P1

sbit rs=P2^0;
sbit rw=P2^1;
sbit en=P2^2;

unsigned char n[]="hello";
unsigned char m[]="welcome rakesh";

void cmd_lcd(unsigned char);
void write_lcd(char);
void delay(unsigned int);

void lcd_int(void)
{
  cmd_lcd(0x38);
  cmd_lcd(0x0c);
  cmd_lcd(0x01);
  cmd_lcd(0x80);
}

void cmd_lcd(unsigned char x)
{
  lcd_data=x;
  rs=0;
  rw=0;
  en=1;
  delay(50);
  en=0;
}

void write_lcd(char s)
{
  lcd_data=s;
  rs=1;
  rw=0;
  en=1;
  delay(500);
  en=0;
}

void delay(unsigned int temp)
{
  unsigned int i,j;

  for(i=0;i<255;i++)
    for(j=0;j<temp;j++)
      ;
}

void main()
{
  unsigned int i;

  lcd_int();

  for (i=0;n[i]!=0;++i)
    write_lcd(n[i]);

  delay(500);

  cmd_lcd(0x01);
  delay(100);

  for (i=0;m[i]!=0;++i)
    write_lcd(m[i]);

  delay(100);

  for (;;)
    ;
}

Is this the second step: Spoon feed the OP by giving ready-to-use code.

Just trying to get the thread out of the kindergarten loop.

Although harmless, including string.h and stdio.h is not necessary.

Thanx to you, one more attempt to activate a brain to start may turn into a failure.

PS: We are not consultants and hence should not provide ready code. :)

"Just trying to get the thread out of the kindergarten loop."

But the big issue is if the OP should learn enough to pass the final exam or just get working code and then fail even harder on next exercise.

What isn't known is basically black magic.
Copying code lines without understanding them results in programs like the one in the first post. Copying code lines from your post will just continue down that same route.

There really is a reason why teachers just don't hand out the final solution to problems and have the students duplicate it. It just fails so badly.

Point taken.

I was just kinda fed up with seeing messages arriving on my rss feed from this ridiculous and annoying thread. Seems my effort just fed the flame. Doh.

yeah, thank you sir, now I really understood my mistakes.. Actually the code i put forward lacked rechecking..
now onwards I'll recheck my code many times and then only will post..
as a beginner i didn't knew how to make well use of this forum. now I think I can do better.

thank you for your encouragement for beginners like me in this forum..

thank you jameel for your sincere and valuable reply and advice.
when i eliminated the VOID in main fn, i got the program error free!!!

"when i eliminated the VOID in main fn, i got the program error free!!!"

You needed a lot more than to remove your extra "void" in main() to get your program error-free.

"when i eliminated the VOID in main fn, i got the program error free!!!

No you didn't.