#include<reg51.h>
sbit in=P1^1;
sbit out=P1^2;
sbit LED=P2^0;
void delay_msec(int);
void main()
{
int count=0;
in=1;
out=1; ////// declaring ‘in’ and ‘out’ as input
LED=0;
while(1)
{
if(in==1)
{
while(!out){}
count++;
LED=1;
delay_msec(1000);
}
if(out==1 && count)
{
while(!in){}
count--;
delay_msec(1000);
if(!count)
LED=0;
}
}
}
// Coding (delay.h):
void delay_msec(int time)
{
int i=0;
while(i<time)
{
TMOD=0x10;
TH1=0xfc;
TL1=0x66;
TR1=1;
while(TF1==0);
{
TR1=0;
TF1=0;
i++;
}
}
}