// USE XTAL 12 MHZ

#include <REGX51.H>

sbit puls=P2^0;

void timer(unsigned char t);// t is usec

void delay_sec(unsigned int m);
void t1_overflow(void) interrupt 3
{
puls=!puls;
}
void main(void)
{

IE=0X88;
TMOD=0X10;
TR1=1;
TH1=0X00;
TL1=0X00;
TF1=0;
while(1)
 {
   if(TF1)
   {
     TH1=0X00;
     TL1=0X00;
     TF1=0;
   }
 }


}