// initialize digital pin LED_BUILTIN to BLINK

void setup() {
  // initialize digital pin LED_BUILTIN as an output.
  pinMode(LED_BUILTIN, OUTPUT);
}

// the loop funtion runs over and over again forever
void loop() {
  digitalWrite(LED_BUILTIN, HIGH); //turn LED OFF
  delay(1000);                     // wait for a second
  digitalWrite(LED_BUILTIN, LOW);  //turn the LED ON
  delay(1000);
}