void main()
{cmcon=7;
Trisa.f0=1; trisb=0; portb=0;
while(1){
 {
if(porta.f0==0){ while(porta.f0==0){}
while(1){(porta.f0) ;
 Portb=0xff;
 while(porta.f0==0){}
while(porta.f0)  Portb=0;}


                  }} } }

void main(){
trisa =0xff;
trisb =0x0;
portb =0;
loop:

if (porta.f0==0){portb.f0=1;}


goto loop;
}