Binary leds sequency - I Arduino Hack Day [ES]

binary_counter.pde

int pins[] = {13,3,4};
int pin;
int inPin = 7;
int num = 0;
int val = 0;
int led = 0;
int maxnum = 0;
int delaytime = 300;
int pinCount = sizeof(pins);


void setup() { 
  for(pin = 0;pin < pinCount; pin= pin+1){   
    pinMode(pins[pin], OUTPUT);
    maxnum = maxnum+pow(2,maxnum);
  }
  pinMode(inPin, INPUT);
}

void loop() {
  val = digitalRead (inPin);

  if (val == LOW) {
      for(pin = 0;pin < pinCount; pin++){   
        digitalWrite(pins[pin], (num >> pin) % 2);
      } 
      num = (num == maxnum) ? 0 : num+1;
      delay (delaytime);
  }
}

Bacana @tagliati, ficou mais limpo com os loops ;)