#include <WiFi.h>
#include <PubSubClient.h>
#include <DHT.h>
// WiFi credentials
//const char* ssid = "F-VIT";
//const char* password = "DcfrMLmS";
const char* ssid = "Wokwi-GUEST";
const char* password = ""; // No password for Wokwi-GUEST
// MQTT Broker details
const char* mqtt_server = "broker.hivemq.com";
const char* topic = "/home/livingroom/temperature";
// DHT Sensor configuration
#define DHTPIN 4
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);
// Initialize WiFi and MQTT Client
WiFiClient espClient;
PubSubClient client(espClient);
void setup() {
Serial.begin(115200);
dht.begin();
// Connect to WiFi
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(1000);
Serial.println("Connecting to WiFi...");
}
Serial.println("Connected to WiFi");
// Configure MQTT Server and Connect
client.setServer(mqtt_server, 1883);
while (!client.connected()) {
Serial.println("Connecting to MQTT...");
if (client.connect("ESP32_Client")) {
Serial.println("Connected to MQTT Broker");
} else {
Serial.print("Failed with state ");
Serial.print(client.state());
delay(2000);
}
}
}
void loop() {
// Read temperature and humidity
float temp = dht.readTemperature();
float hum = dht.readHumidity();
// Publish data if valid
if (!isnan(temp) && !isnan(hum)) {
char payload[50];
snprintf(payload, sizeof(payload), "{\"value\": %.2f, \"unit\": \"C\"}", temp);
client.publish(topic, payload);
Serial.println("Published Temperature Data");
}
client.loop();
delay(5000); // Publish every 5 seconds
}