GitHub - nanassound/midimesh_esp32: ESP32 midi controller over UDP network. Firmware is using AtomVM.

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midiMESH ESP32

Open-source modular MIDI devices ecosystem over WiFi using ESP32-C3 and AtomVM. Control your DAW and devices wirelessly with various hardware controllers.

Key Features:

  • MIDI CC messages over UDP/WiFi
  • Concurrent multi-knob support with Elixir processes
  • Operational in AP mode or STA mode
  • Modular hardware designs (Eurorack-compatible)
  • Runs AtomVM (Erlang VM) on ESP32-C3

Demos:

Project Structure

midimesh_esp32/
├── firmware/     # Elixir/AtomVM firmware for ESP32-C3
└── hardware/     # KiCad PCB design files for midiMESH devices

This repository contains both the firmware and hardware designs for the midiMESH ecosystem.

  • Firmware: See firmware/ for the Elixir code that runs on the ESP32-C3. Detailed build, flash, and configuration instructions are in firmware/README.md.
  • Hardware: See hardware/ for various midiMESH device designs. Each subdirectory contains KiCad design files for a specific controller.

Firmware

The firmware is written in Elixir and runs on AtomVM, a lightweight Erlang VM for embedded systems.

Features:

  • Supports multiple analog potentiometers with concurrent processing
  • Sends MIDI CC (Control Change) messages over UDP
  • LED indicator for WiFi connection status
  • Broadcasts to local network on port 4000
  • Modular architecture with separate modules for Knob, Switch, MIDI operations, and Config

Hardware pins (configurable in code):

  • Knob 1: GPIO 0
  • Knob 2: GPIO 1
  • LED: GPIO 8

For complete setup instructions, WiFi configuration, building, and flashing, see firmware/README.md.

Hardware

The midiMESH ecosystem includes various Eurorack-compatible MIDI controller designs, each tailored for different control needs.

Available Designs:

  • Slide & Twist: Controller with knobs and slide potentiometer
  • Control Voltage (coming soon): Wireless MIDI to CV for Eurorack modular synth

Design Files:

  • KiCad v9.0 schematics and PCB layouts
  • Location: hardware/
  • Each device has its own subdirectory with complete design files

For detailed component information and specifications for each controller, see hardware/README.md.

The design files are provided as-is for viewing, modification, and manufacturing.

Getting Started

Prerequisites

For Firmware:

For Hardware:

  • KiCad 9.0 or later to view/edit design files

Quick Start

  1. Flash firmware: Follow the detailed instructions in firmware/README.md to configure WiFi, build, and flash the ESP32-C3.
  2. View hardware designs: See hardware/README.md for available midiMESH devices. Open the KiCad project files to explore or modify the PCB designs.
  3. Receive MIDI: Use the companion midiMESH desktop receiver to receive UDP MIDI and forward it to a virtual MIDI port for use in your DAW.

Related Projects

  • midimesh_desktop_receiver: Desktop application that receives UDP MIDI messages from the ESP32 and forwards them to a virtual MIDI port (e.g., IAC Driver on macOS).

License

This project is dual-licensed:

Firmware License

The firmware (in firmware/) is licensed under the Apache 2.0 license.

See firmware/LICENSE.md for full license text.

Hardware License

The hardware design (in hardware/) is licensed under the CERN Open Hardware License v2 - Weakly Reciprocal (CERN-OHL-W).

See hardware/LICENSE.md for full license text.

Derivative Works Guidelines

Both licenses allow you to freely use, study, modify, and distribute this project and create derivative works.

Important: You must NOT use the "Nanas Sound" name, logo, or any other Nanas Sound identifiers in your derivative works. Nanas Sound is a business name of Nanas Sound OÜ.

Examples of acceptable naming:

  • Correct: "Strawberry Field - MIDIYummy"
  • Incorrect: "Nanas Sound's midiMESH" or "Based on Nanas Sound midiMESH"

We encourage you to create and share your own versions of this project while respecting our trademark.

Contributing

Contributions, issues, and feature requests are welcome. Feel free to open an issue or submit a pull request.

Copyright 2025 Nanas Sound OÜ