Program Timer 0 to generate a square wave of 0.5KHz

 XLAT = 20MHz


#include<reg51.h>
sbit OUTPUT=P1^7;
void delay()
{
    unsigned int i;
    TMOD=TMOD & 0xF0;
    TMOD=TMOD | 0x01;
    TH0=0xF2;
    TL0=0xFB;
    TR0=1;
    while(TF0==0);
    TR1=0;
}
void main()
{
    while(1)
    {
        OUTPUT=1;
        delay();
        OUTPUT=0;
    }
}