int ledPin = 11;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(ledPin, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(ledPin, HIGH);
  Serial.println("LED on");
  delay(500);
  digitalWrite(ledPin, LOW);
  Serial.println("LED off");
  delay(500);
}