Retro Meets Modern: Transforming a Vintage Rotary Dial MonoPhone into a Cellphone with Elixir/Nerves

ElixirConf · January 7, 2025, 2:00pm

ElixirConf US 2024 - Bryan Green

Welcome to ElixirConf

This project transforms a vintage rotary dial MonoPhone into a fully functional cellphone using Elixir and Nerves, merging old-world charm with modern technology. We explore challenges and solutions in hardware-software integration, demonstrating the technical prowess of Elixir and inspiring innovative applications.

Choosing Elixir and Nerves for the Challenge: Elixir and Nerves were the natural choices for this project due to their capabilities in managing and controlling physical devices. Elixir’s functional paradigm and actor-based concurrency model mapped well to hardware interaction, while Nerves provided specialized tools for embedded systems development. A key benefit of Nerves is its ability to deploy new software over the air, facilitating seamless updates and maintenance of the MonoPhone project.

Elixir’s Functional Programming and State Management: Elixir’s functional programming paradigm excels in handling state in applications where precision and reliability are paramount. In the MonoPhone project, managing the device’s state—from idle and dialing to in-call and disconnect—was crucial for accurately replicating the behavior of traditional telephones and modern cellphones. By harnessing Elixir’s capabilities to implement a finite state machine, we elegantly managed transitions between these states based on user interaction and network communication events.

Future Implications: Once the concepts introduced in this talk are understood, it opens up many possibilities for future projects. Understanding how to detect changes to inputs and learning to control a telephone have limitless possibilities. Some potential future projects include:

Creating a home automation system that can be controlled remotely via phone calls or SMS. Building a smart doorbell system that notifies homeowners of visitors and allows for two-way communication. Implementing a security system with motion detection and alarm capabilities, controllable via phone or SMS. Constructing a fleet management solution for tracking and monitoring vehicles using GPS and cellular communication. Building your own custom cellphone. What Viewers Will Learn: This project will illuminate how GenServers intricately handle mapping low-level inputs, such as hook, dial, and incoming call indicators, and transmit high-level messages to the finite state machine (FSM) for triggering state changes, and controlling the modem. Viewers will also see how Circuits.GPIO is used to translate clicks of the rotary dialer and hook into commands. This segment promises to be the most rewarding part of the presentation, providing valuable insights into the practical implementation of Elixir’s concurrency tools in real-world scenarios.

Why This Presentation Is Important for the Elixir Community: This presentation offers a practical demonstration of Elixir and Nerves’ capabilities beyond traditional web development, inspiring attendees to explore new horizons in their projects. It showcases the potential for leveraging Elixir’s concurrency tools in real-world scenarios, bridging the gap between the digital and physical realms. Hopefully, this will be viewed as a fun project that’s approachable to a hobbyist, encouraging more individuals to engage with Elixir and Nerves in creative and innovative ways.

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D4no0 · January 9, 2025, 9:51am

Nice presentation!

Is @codestorm1 the presenter?