void setup() {
  // Initialize pin 12 as an output
  pinMode(12, OUTPUT);
}

void loop() {
  // Turn the LED on (HIGH is the voltage level)
  digitalWrite(12, HIGH);
  // Wait for 1 second
  delay(1000);
  // Turn the LED off by making the voltage LOW
  digitalWrite(12, LOW);
  // Wait for 1 second
  delay(1000);
}