Remoto: IoT plug-and-play firmware with MQTT

Introduction

Throughout my career, I've worked extensively on IoT projects for industrial and home automation applications—environments where users often lack programming expertise and debugging skills. While I’ve relied on open-source tools like Arduino, even this can seem daunting to end-users who prefer expensive proprietary solutions over the challenge of writing code.

This project is my attempt to lower that barrier by creating a plug-and-play IoT solution, making open-source hardware more accessible and user-friendly.

Hardware

For this project, I chose the Arduino Opta, a powerful yet cost-effective IoT device. My firmware supports both the Wi-Fi and RS485 variants, but it is also fully compatible with the basic hardware version. The Opta offers a rich set of features, making it an excellent foundation for a flexible and scalable IoT solution.

Firmware

The firmware design reflects lessons learned in real-world deployments, focusing on three core aspects:

1. Remote Telemetry and Control

The firmware uses MQTT, a widely adopted messaging protocol, to publish real-time telemetry data and receive commands. Input statuses are published to MQTT topics at regular intervals, while outputs can be controlled by subscribing to specific topics. This ensures seamless integration with most IoT ecosystems.

2. Intuitive Web Interface

The device hosts an interactive web-based UI for real-time monitoring and configuration. This interface allows users to:

• View the status of inputs and outputs.
• Monitor the MQTT connection and last message sent.
• Configure settings such as device name, IP address, MQTT broker credentials, and input modes (analog or digital).

All changes made via the UI are saved to flash storage, ensuring persistence across power cycles.

3. Plug-and-Play Usability

Thanks to the intuitive web interface, users can set up and operate the device without any coding skills. It’s truly a plug-and-play solution!

Open Source and Expandable

The source code for the firmware is freely available on GitHub. You’re welcome to explore, customize, and improve it to suit your own needs. Whether you're a beginner or a seasoned developer, this project is a starting point for creating accessible IoT solutions.

Happy hacking! 🚀