void setup() {
  // setup the pins
  pinMode(13, OUTPUT); // LED L is connected to pin 13. We will use pin 13 to output voltage levels.

}

void loop() {
  // the loop function runs the code over and over again
  digitalWrite(13, HIGH); // output high voltage
  delay(1000); // delay by 1000ms (1 sec)
  digitalWrite(13, LOW); // output low voltage
  delay(1000); // delay by 1000 ms


}