#define LDRPIN 2
#define ledRed 4

void setup() {
  pinMode(LDRPIN, OUTPUT);
  pinMode(ledRed, OUTPUT);
  Serial.begin(115200);
  delay(1000);
}

void loop() {
  int val = analogRead(LDRPIN); 
  Serial.println(val);
  

  int threshold = 500;
  
  if (val < threshold) {
    digitalWrite(ledRed, HIGH); 
  } else {
    digitalWrite(ledRed, LOW); 
  }
  
  delay(50);
}