#define LED_PIN D1

void setup() {
  Serial.begin(9600);
  pinMode(LED_PIN, OUTPUT);
  Serial.println("Ready and waiting for commands...");
}

void loop() {
  if (Serial.available() > 0) {
    String command = Serial.readStringUntil('\n');
    command.trim();
    Serial.print("Received command: ");
    Serial.println(command);
    if (command == "ON") {
      digitalWrite(LED_PIN, HIGH);
      Serial.println("LED turned ON");
    } else if (command == "OFF") {
      digitalWrite(LED_PIN, LOW);
      Serial.println("LED turned OFF");
    } else {
      Serial.println("Unknown command");
    }
  }
}