GPIO is not working on the board but working fine in simulator

Good morning guys,

I have got a problem with LPC2148. I am using PORT0 as GPIO pins. The program runs fine in the simulator but there is nothing when i port the hex on the board.

Here is the code:

#include<lpc214x.h>
#include "delay.h"

void main()
{ PINSEL0=0x00000000; IODIR0=0xffffffff;

while(1) { IOPIN0=0xffffffff; delay(500); IOPIN0=0x00000000; delay(500); }
}

delay is nothing but come commands running during that time. Simulator shows good behaviour of delay functions.

I have checked on "Use Memory layout from the target dialog". But still no output.
Am i doing something wrong in the code. or should i take care of something else too?
Please help.