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);
}