#include <WiFi.h>
#include <PubSubClient.h>
#include <DHTesp.h>
#define DHTPIN 18
#define DHTTYPE22
DHTesp dht;
// Update these with values suitable for your network.
const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* mqtt_server = "broker.hivemq.com";
WiFiClient espClient;
PubSubClient client(espClient);
unsigned long lastMsg = 0;
void setup_wifi() { //perintah koneksi wifi
delay(10);
// We start by connecting to a WiFi network
Serial.println();
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.mode(WIFI_STA); //setting wifi chip sebagai station/client
WiFi.begin(ssid, password); //koneksi ke jaringan wifi
while (WiFi.status() != WL_CONNECTED) { //perintah tunggu esp32 sampi terkoneksi ke wifi
delay(500);
Serial.print(".");
}
randomSeed(micros());
Serial.println("");
Serial.println("WiFi connected");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
}
void callback(char* topic, byte* payload, unsigned int length) { //perintah untuk menampilkan data ketika esp32 di setting sebagai subscriber
Serial.print("Message arrived [");
Serial.print(topic);
Serial.print("] ");
for (int i = 0; i < length; i++) { //mengecek jumlah data yang ada di topik mqtt
Serial.print((char)payload[i]);
}
Serial.println();
}
void reconnect() { //perintah koneksi esp32 ke mqtt broker baik itu sebagai publusher atau subscriber
// Loop until we're reconnected
while (!client.connected()) {
Serial.print("Attempting MQTT connection...");
// perintah membuat client id agar mqtt broker mengenali board yang kita gunakan
String clientId = "ESP32Client-";
clientId += String(random(0xffff), HEX);
// Attempt to connect
if (client.connect(clientId.c_str())) {
Serial.println("Connected");
client.subscribe("/IoT/DHTSuhu"); //perintah subscribe data ke mqtt broker
client.subscribe("/IoT/DHTKelembapan");
} else {
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" try again in 5 seconds");
// Wait 5 seconds before retrying
delay(5000);
}
}
}
void setup() {
Serial.begin(115200);
setup_wifi(); //memanggil void setup_wifi untuk dieksekusi
client.setServer(mqtt_server, 1883); //perintah connecting / koneksi awal ke broker
client.setCallback(callback); //perintah menghubungkan ke mqtt broker untuk subscribe data
dht.setup(DHTPIN, DHTesp::DHT22); // Inisialisasi sensor DHT
}
void loop() {
if (!client.connected()) {
reconnect();
}
client.loop();
unsigned long now = millis();
if (now - lastMsg > 2000) {
lastMsg = now;
float temp = dht.getTemperature();
float hum = dht.getHumidity();
String tempStr = String(temp, 2);
client.publish("/IoT/DHTSuhu", tempStr.c_str());
String humStr = String(hum, 1);
client.publish("/IoT/DHTKelembapan", humStr.c_str());
Serial.println("Suhu: " + String(temp, 2) + "°C");
Serial.println("Kelembaban: " +String(hum, 1) + "%");
Serial.println("---");
}
}