KMK: Clackety Keyboards Powered by Python

KMK is a feature-rich and beginner-friendly firmware for computer keyboards written and configured in CircuitPython. KMK is currently in public beta, however should handle almost all workflows without major issues.

You can always find the latest releases on our CDN, in compiled and optimized and raw, hackable text file forms. These follow the master branch here on GitHub.

If you need support with KMK or just want to say hi, find us in #kmkfw:klar.sh on Matrix. This channel is bridged to Discord here for convenience.

If you ask for help on chat or open a bug report, if possible please give us your commit SHA, found by running from kmk.consts import KMK_RELEASE; print(KMK_RELEASE) in the REPL on your controller.

Features

• Fully configured through a single, easy to understand Python file that lives on a "flash-drive"-esque space on your microcontroller - edit on the go without DFU or other devtooling available!
• Single-piece or two-piece split keyboards are supported
• Chainable keys such as KC.LWIN(KC.L) to lock the screen on a Windows PC
• Built-in unicode macros, including emojis
• Multiple vim-inspired leader key modes
• RGB underglow and LED backlights
• One key can turn into many more based on how many times you tap it

Coming (hopefully) soon: Bluetooth support! Stay tuned.

Getting Started

• Start by grabbing a supported microcontroller. Broadly speaking, KMK supports any device CircuitPython does, but KMK requires a decent bit of RAM, and in general requires a working USB HID stack, which leads us to recommend the following controllers:

  • Adafruit ItsyBitsy M4 Express*
  • Adafruit Feather M4 Express
  • Adafruit Feather nRF52840 Express
  • MakerDiary nRF52840 MDK
  • SparkFun Pro nRF52840 Mini

  * The ItsyBitsy M4 Express is the only controller we currently support in non-handwired configurations, using our ItsyBitsy to Pro Micro converter PCB designed by @siddacious and @kdb424. It is our most-recommended MCU until the ItsyBitsy is updated with an nRF52840 chip

  Some other controllers, such as the Feather M0 Express, are usable in reduced functionality modes and may require custom hackery. For example, @kdb424 uses a ItsyBitsy M0 Express as a barebones matrix scanner in a split keyboard configuration here. Use such controllers at your own risk.

• Ensure CircuitPython 4.0.0 or newer is installed on your controller. We recommend the latest stable version from circuitpython.org. Flashing instructions vary by device: all Adafruit boards can be flashed using their instructions, other boards generally have their instructions in the CircuitPython repository under the ports/atmel-samd/boards/<your board here> and ports/nrf/boards/<your board here> directories. If all else fails, consult your device's official documentation.

• Download the latest KMK release and extract the zip to the USB drive exposed by CircuitPython, typically labeled CIRCUITPY. Again, we'll defer to Adafruit's documentation on adding libraries to a CircuitPython installation. You should end up with a folder called kmk and a file called boot.py, both living at the top of this USB drive.

• Define your keyboard in a file called main.py on this CIRCUITPY drive and get tinkering! Examples of both handwired and ProMicro->ItsyBitsy converted boards exist under the user_keymaps/ tree, and feel free to submit a pull request of your own definitions! At this point, you'll want to look through docs/ in the source tree to explore the functionality at your disposal.

Linux, BSD, and MacOS users can also make use of the Makefile provided in this source tree to flash KMK and a keymap using rsync. This is advanced functionality outside the scope of this README, but it's documented in the docs/ tree.

The KMK Team

KMK is primarily written and maintained by @klardotsh and @kdb424, but contributions are welcome from all, whether it's in the form of code, documentation, hardware designs, feature ideas, or anything else that comes to mind. KMK's contributors and other helpers are listed alphabetically by username below (we'll try to keep this up to date!):

• Dan Halbert (@dhalbert)
• Elvis Pfützenreuter (@elvis-epx)
• Kyle Brown (@kdb424)
• Josh Klar (@klardotsh)
• Limor Fried (@ladyada)
• Ryan Karpinski (@rk463345)
• @siddacious
• Scott Shawcroft (@tannewt)

While Adafruit employees and affiliates are included in the above list and their help has been crucial to KMK's success, KMK is not an official Adafruit project, and the Core team is not compensated by Adafruit for its development.

Code Style

KMK uses Black with a Python 3.6 target and, (controversially?) single quotes. Further code styling is enforced with isort and flake8 with several plugins. make fix-isort fix-formatting before a commit is a good idea, and CI will fail if inbound code does not adhere to these formatting rules. Some exceptions are found in setup.cfg loosening the rules in isolated cases, notably user_keymaps (which is also not subject to Black formatting for reasons documented in pyproject.toml).

License, Copyright, and Legal

All software in this repository is licensed under the GNU Public License, verison 3. All documentation and hardware designs are licensed under the Creative Commons Attribution-ShareAlike 4.0 license. Contributions to this repository must use these licenses unless otherwise agreed to by the Core team.