int ledPin = 3;
int analogPin = 5;
int val = 0;
void setup() {
  pinMode(ledPin, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  val = analogRead(analogPin);
  Serial.print("val = ");
  Serial.println(val);
  if (val < 500) {
    digitalWrite(ledPin, HIGH);
    Serial.println("LED ON");
    Serial.println();
  }
  else {
    digitalWrite(ledPin, LOW);
    Serial.println("LED OFF");
    Serial.println();
  }
  delay(1000);
}