void main() {

int value;
int counter=0;

ansel=0;
anselh=0;
trisa=0x00;
trisb=0x00;
porta=0x00;
value=0b10000000;

while(1){

  if(value==0){
    value=0b10000000;
    counter=0;
  }

  porta = value;

  if(counter==2){
    value = value >> 1;
    counter = 0;
  } else {
    value = value << 1;
    counter++;
  }

  Delay_ms(20);

}

}