const int analogInputPin = A0; 
const int ledPin = 12; 
int sensorValue = 0;

void setup() {
  Serial.begin(115200);
  pinMode(ledPin, OUTPUT);
}

void loop() {
  sensorValue = analogRead(analogInputPin);

  Serial.print("DO SANG LED : ");
  Serial.println(sensorValue);

  if (sensorValue >= 1000 && sensorValue < 2500) {
    digitalWrite(ledPin, HIGH);
    delay(500);
    digitalWrite(ledPin, LOW);
    delay(500);  
  } 
  else if (sensorValue >= 3500 ) {
    digitalWrite(ledPin, LOW);
  } else {
    digitalWrite(ledPin, HIGH);  
  }
}