/*const int S0 = 2;
const int S1 = 3;
const int S2 = 4;
const int S3 = 5;
const int SIG = 6;
*/

void setup() {
  DDRD = B01111100;

}

void loop() {
  // put your main code here, to run repeatedly:

  PORTD = B01000000;
  PORTD = B01100000;
  PORTD = B01010000;
  PORTD = B01110000;

}