#define BUTTON_PIN 4
#define LED_PIN 2

String dataMasuk = "";

bool lastButtonState = HIGH;
bool currentButtonState;

void setup() {
  Serial.begin(115200);
  Serial2.begin(115200, SERIAL_8N1, 16, 17);

  pinMode(BUTTON_PIN, INPUT_PULLUP);

  Serial.begin(115200);
  Serial2.begin(115200, SERIAL_8N1, 16, 17);

  pinMode(LED_PIN, OUTPUT);
}

void loop() {
  currentButtonState = digitalRead(BUTTON_PIN);

  if (currentButtonState != lastButtonState) {
    if (currentButtonState == LOW) {
      Serial.println("Kirim: ON");
      Serial2.println("ON");
    } else {
      Serial.println("Kirim: OFF");
      Serial2.println("OFF");
    }
  }

  lastButtonState = currentButtonState;

  if (Serial2.available()) {
    dataMasuk = Serial2.readStringUntil('\n');
    dataMasuk.trim();

    Serial.print("Terima: ");
    Serial.println(dataMasuk);

    if (dataMasuk == "ON") {
      digitalWrite(LED_PIN, HIGH);
    } 
    else if (dataMasuk == "OFF") {
      digitalWrite(LED_PIN, LOW);
    }
  }
}