#define LED_BUILTIN 2

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(LED_BUILTIN, OUTPUT); //set digital pin as output
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(LED_BUILTIN, HIGH); //Turn on LED
  Serial.println("Turn LED ON");
  delay(1000);
  digitalWrite(LED_BUILTIN, LOW); //Turn off LED
  Serial.println("Turn LED OFF");
  delay(1000);
}