   //start serial connection
   Serial.begin(9600);
   //configure pin2 as an input and enable the internal pull-up resistor
-  pinMode(2, INPUT_PULLUP); 
+  pinMode(2, INPUT_PULLUP);
+  pinMode(13, OUTPUT); 
 
 }
 

 
 The circuit: 
 * Momentary switch attached from pin 2 to ground 
 
 Unlike pinMode(INPUT), there is no pull-down resistor necessary. An internal 
 20K-ohm resistor is pulled to 5V. This configuration causes the input to 

  int sensorVal = digitalRead(2);
  //print out the value of the pushbutton
  Serial.println(sensorVal);
  
  // Keep in mind the pullup means the pushbutton's
  // logic is inverted. It goes HIGH when it's pressed,
  // and LOW when it's not. Turn on pin 13 when the 
  // button's pressed, and off when it's not:
  if (sensorVal == HIGH) {
    digitalWrite(13, LOW);
  } 
  else {
    digitalWrite(13, HIGH);
  }
}



