#Menelaus

A firmware for the Atreus keyboard, written in Microscheme.

This is my (jturner) personal fork of the codebase found on sourcehut.

See this article about how it works.

#Features

• 6KRO (6 simultaneous keys, plus 4 modifiers)
• Software debouncing
• Multiple layers, momentary and sticky (limited only by memory)
• Combo keys (a single keystroke can send a modifier and a non-modifier)
• Bind arbitrary Microscheme functions to a key
• ~300 lines of code
• Qwerty and Dvorak layouts; easy to add more

#Usage

Install microscheme from source; place microscheme executable on your $PATH. Version 3bc5611 from March 2020 is known to work.

Requires avrdude for uploading to the controller on the keyboard; install with your package manager of choice.

Replace /dev/ttyU0 with the path your OS assigns to the USB bootloader of the microcontroller.

$ make upload USB=/dev/ttyU0

Once you run that, put the device in bootloader mode; sometimes this can be invoked by a key combo and sometimes a hard reset is necessary. On the A-star Micro used in the Atreus kits, this is done by shorting GND and RST twice in under a second, which causes the onboard LED to pulse. The Keyboardio Atreus has a reset button you can press with a pin to the bottom of the board.

#Layout

By default you get the qwerty layout. You can copy qwerty.scm to mylayout.scm and make changes, (you can see a list of available keycodes in keycodes.scm) then upload with:

$ make upload USB=/dev/ttyU0 LAYOUT=mylayout

There is also a multidvorak layout which is designed to send the right keycodes with the assumption that the OS is set to use Dvorak, but it also includes layers for "hard Dvorak".

The default layout is based on the Keyboardio Atreus, except that for older 42-key builds, the percent key is replaced with backtick, and backslash is fn+semicolon.

#License

Copyright © 2014-2020 Phil Hagelberg and contributors

Released under the GNU GPL version 3 or any later version.

Uses PJRC USB Keyboard library which is Copyright © 2009 PJRC.COM, LLC and released under the MIT/X11 license.