Smart Light Control with ESP32 and MQTT

11.12.2024 - Engine: Gemini

Smart Light Control with ESP32 and MQTT

Components

• ESP32 module
• LED strip
• Relay
• MOSFET
• MQTT broker (e.g., Mosquitto)

Programming

Step 1: Set up ESP32

Connect the ESP32 to your computer and download the Arduino IDE. Install the ESP32 library from the Arduino IDE manager.

Step 2: Add MQTT Library

Add the MQTT library to the project, such as the PubSubClient library.

Step 3: Connect to MQTT Broker

Establish a connection to the MQTT broker and configure the topics to be used.

Step 4: Control LEDs

Use the digitalWrite() function to control the LEDs via the relay and MOSFET.

Step 5: Subscribe to MQTT Messages

Subscribe to the MQTT topics which will be used to control the LEDs.

Step 6: Process Messages

Process the received MQTT messages and control the LEDs accordingly.

Sample Code

#include <WiFi.h>
#include <PubSubClient.h>

const char* ssid = "Your_WiFi_Name";
const char* password = "Your_WiFi_Password";
const char* mqtt_broker = "mqtt.example.com";
const int mqtt_port = 1883;
const char* topic = "home/lights";

WiFiClient espClient;
PubSubClient client(espClient);

void setup() {
  Serial.begin(115200);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    Serial.print(".");
    delay(500);
  }
  Serial.println("WiFi connected");
  client.setServer(mqtt_broker, mqtt_port);
}

void loop() {
  if (!client.connected()) {
    Serial.print("Connecting to MQTT broker...");
    while (!client.connected()) {
      if (client.connect("ESP32-Light")) {
        Serial.println("connected");
        client.subscribe(topic);
      } else {
        Serial.print(".");
        delay(1000);
      }
    }
  }
  client.loop();
}

void callback(char* topic, byte* payload, unsigned int length) {
  String message = String((char*)payload);
  if (message == "ON") {
    digitalWrite(LED_PIN, HIGH);
  } else if (message == "OFF") {
    digitalWrite(LED_PIN, LOW);
  }
}