byte ldr = A5;
byte led = 9;
int nilai;

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

}

void loop() {
 nilai = analogRead(ldr);
 Serial.print("Nilai LDR : ");
 Serial.println(nilai);

if(nilai < 500){
  digitalWrite(led, HIGH);
  Serial.println("Keadaan gelap, lampu menyala");
}else{
  digitalWrite(led, LOW);
  Serial.println("Keadaan terang, lampu mati");
}
 delay(1000);
}