/rusty-maschine

Usermode USB HID driver for a Native Instruments Maschine Mikro MK2

Primary LanguageRust

Usermode API library for a NI Maschine Mikro MK2

This is a learning/experimentation project for Rust.

Much of the protocol implementation details have been gleaned from the cabl project.

The ultimate end goal is to move this project onto a microcontroller (likely the Raspberry Pi Pico) to use the controller to either output MIDI or act as a CV source or sequencer.

NOTE: this is a first Rust project so will contain approaches that are non standard. And includes no tests (not quite got there yet!).

Current status

Completed:

  • Mono and RGB LED's working for all buttons
  • Button events being generated (including shift)
  • Encoder generating up/down events
  • Pads generating events as velocity changes.
  • Display initialising with fill/invert and get/set pixels
  • Error handling in place
  • Translating button ID's into enums
  • Callback/Observer for events

ToDo:

  • Port parts of the Adafruit GFX library to work with the display buffer to provide some graphics primitives
  • Convert into a crate that can be easily integrated into other applications (not there is a caveat regarding hidapi that only a single hidapi::Context can exist).

Development

NOTE: This code was developed on a Debian Linux based OS, instructions below may work on other distributions.

Uses the hidapi wrapper as the interfaces to the USB device.

There are two approaches to getting a debugger running you can either run an lldb-server as root (which is risky) or the better option of configuring udev to give read/write access to the USB device.

  • As root (or sudo) create the file /etc/udev/rules.d/99-native-instruments.rules with the following entry for all Native Instruments devices:

    SUBSYSTEM=="usb", ATTRS{idVendor}=="17cc", MODE="0666"

    or to limit to just a Maschine Mikro Mk2 use:

    SUBSYSTEM=="usb", ATTRS{idVendor}=="17cc", ATTTRS{idProduct}=="1200", MODE="0666"

  • Reload the UDev config:

    sudo udevadm control --reload-rules

  • Reconnect the USB device.

You should now be able to access the device (and run/debug) as a normal user.