basic-threshold.ino

int ledPin = 11;
int sensorInput = A0;

void setup() {
  pinMode(ledPin, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  int lightLevel = analogRead(A0);

  if (lightLevel < 512) {
    digitalWrite(ledPin, HIGH);
  } else {
    digitalWrite(ledPin, LOW);
  }
  Serial.println(lightLevel);
}