NodeMCU 16x2 i2c dht11

// sda pin d2

// scl pin d1

// dht11 pin d4

#include <Wire.h>

#include <LiquidCrystal_I2C.h>

#include <DHT.h>

// Definisi untuk DHT11

#define DHT_PIN 2      // GPIO2 (D4 pada NodeMCU)

#define DHT_TYPE DHT11

DHT dht(DHT_PIN, DHT_TYPE);

// Variabel LCD - ganti dengan alamat I2C yang terbaca

LiquidCrystal_I2C lcd(0x27, 16, 2); // Ganti 0x27 dengan alamat yang terbaca

// Variabel sensor

float temperature = 0;

float humidity = 0;

unsigned long previousMillis = 0;

const long interval = 2000; // Update setiap 2 detik

// Simbol custom degree

byte degreeSymbol[8] = {

  B00110,

  B01001,

  B01001,

  B00110,

  B00000,

  B00000,

  B00000,

  B00000

};

void setup() {

  Serial.begin(115200);

  Serial.println("Starting DHT11 with LCD System...");

  // Inisialisasi LCD

  lcd.init();

  lcd.backlight();

  lcd.createChar(0, degreeSymbol); // Buat custom character degree

  // Inisialisasi DHT11

  dht.begin();

  // Tampilkan splash screen

  displaySplashScreen();

  Serial.println("System Ready");

}

void loop() {

  unsigned long currentMillis = millis();

  if (currentMillis - previousMillis >= interval) {

    previousMillis = currentMillis;

    // Baca data dari sensor DHT11

    readDHT();

    // Update display LCD

    updateDisplay();

  }

}

void readDHT() {

  // Baca temperatur dalam Celsius

  float newTemp = dht.readTemperature();

  // Baca kelembaban

  float newHumidity = dht.readHumidity();

  // Cek jika pembacaan gagal

  if (isnan(newTemp) || isnan(newHumidity)) {

    Serial.println("Failed to read from DHT sensor!");

    // Tampilkan error di LCD

    displayError();

    return;

  }

  temperature = newTemp;

  humidity = newHumidity;

  // Tampilkan data di Serial Monitor

  Serial.print("Temperature: ");

  Serial.print(temperature);

  Serial.print(" °C, Humidity: ");

  Serial.print(humidity);

  Serial.println(" %");

}

void displaySplashScreen() {

  lcd.clear();

  lcd.setCursor(0, 0);

  lcd.print("DHT11 MONITOR");

  lcd.setCursor(0, 1);

  lcd.print("Initializing...");

  delay(2000);

  lcd.clear();

  lcd.setCursor(0, 0);

  lcd.print("NodeMCU + LCD");

  lcd.setCursor(0, 1);

  lcd.print("DHT11 Sensor");

  delay(2000);

}

void updateDisplay() {

  lcd.clear();

  // Baris 1: Temperature

  lcd.setCursor(0, 0);

  lcd.print("Temp: ");

  lcd.print(temperature, 1); // 1 digit desimal

  lcd.write(0); // Tampilkan simbol degree

  lcd.print("C");

  // Baris 2: Humidity

  lcd.setCursor(0, 1);

  lcd.print("Humid: ");

  lcd.print(humidity, 1); // 1 digit desimal

  lcd.print("%");

}

void displayError() {

  lcd.clear();

  lcd.setCursor(0, 0);

  lcd.print("Sensor Error!");

  lcd.setCursor(0, 1);

  lcd.print("Check DHT11");

}

// Fungsi alternatif dengan tampilan yang lebih rapat

void updateDisplayCompact() {

  lcd.clear();

  // Baris 1

  lcd.setCursor(0, 0);

  lcd.print("T:");

  lcd.print(temperature, 1);

  lcd.write(0);

  lcd.print("C");

  // Baris 2  

  lcd.setCursor(0, 1);

  lcd.print("H:");

  lcd.print(humidity, 1);

  lcd.print("%");

  // Tambahkan status di sebelah kanan

  lcd.setCursor(11, 0);

  lcd.print("DHT11");

  lcd.setCursor(11, 1);

  lcd.print("OK");

}

// Fungsi untuk membaca sensor dengan retry

bool readDHTWithRetry() {

  int retryCount = 0;

  const int maxRetries = 3;

  while (retryCount < maxRetries) {

    float newTemp = dht.readTemperature();

    float newHumidity = dht.readHumidity();

    if (!isnan(newTemp) && !isnan(newHumidity)) {

      temperature = newTemp;

      humidity = newHumidity;

      return true;

    }

    retryCount++;

    delay(500);

  }

  return false; // Gagal setelah retry

}