Kode

Build a centralized smart home hub using Kode Dot. Control lights, fans, and sensors over MQTT with a clean touchscreen interface.

Overview

In this project, we build a smart home controller using the Kode Dot as the central hub. The device connects to your local MQTT broker and provides a touchscreen UI to control lights, read temperature sensors, and manage automation rules.

What you'll learn

Setting up MQTT on ESP32-S3
Building LVGL touchscreen interfaces
Reading I2C sensors (BME280)
Controlling relays via GPIO expansion

Hardware Setup

Components

Kode Dot (main controller)
Inventor Module (GPIO breakout)
4-channel relay module
BME280 temperature/humidity sensor
Jumper wires

Wiring

Connect the relay module to GPIOs 1-4 on the Inventor Module. The BME280 connects via I2C (SDA/SCL on the magnetic connector).

MQTT Client Setup

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

const char* ssid = "your-wifi";
const char* mqtt_server = "192.168.1.100";

WiFiClient espClient;
PubSubClient client(espClient);

void setup() {
  WiFi.begin(ssid, password);
  client.setServer(mqtt_server, 1883);
  client.setCallback(callback);
}

void callback(char* topic, byte* payload, unsigned int length) {
  String msg = String((char*)payload).substring(0, length);
  if (String(topic) == "home/light/1") {
    digitalWrite(RELAY_1, msg == "ON" ? HIGH : LOW);
  }
}