ZMK Module for MNT Reform Keyboard

NOTE: This firmware is a work in progress and is not stable. Use at your own risk.

This is an unofficial port of the ZMK firmware to the MNT Reform Keyboard V4.0 based on the RP2040 MCU.

Using this firmware as a standalone keyboard is currently fully supported and functional.

Using this firmware within a Reform laptop (Classic & Next) is largely implemented but untested as I do not have any laptop hardware at the moment.

Status

The USB HID is currently unstable and will crash often making the keyboard unresponsive to the host

• If this happens, the keyboard can be reset by pressing CIRCLE -> R
• The keyboard can be put into flashing mode by pressing CIRCLE -> X
• The keyboard can unlocked for modification in ZMK Studio by pressing:
  • CIRCLE -> U
  • Hold the top-left key (ESC by default) for 5 seconds

Functional

• Reform device tree and pinctrl
• Keyboard matrix and function layers
• RGB - WS2812 driver on PIO0
• Display - Custom Display Code
  • does not use ZMK's display widgets
• Menu - Custom Menu ZMK Behavior
  • Matches the circle menu from original firmware
• MNT Reform system controller support
• Settings saving & loading
• Physical keyboard layout definition
• ZMK Studio Support
• MNT Reform Next Trackpad
  • Mouse emulation, simple gestures (on-engine)

Planned

• Precision Trackpad HID support for advanced multitouch gestures
• MNT Reform Pocket support

Testing

Using a prebuilt uf2 firmware

• Download the most recent build from the latest release

Building from source

• Follow the standard ZMK documentation to setup a native toolchain
• Use the current main branch of ZMK that is on top of Zephyr 4.1
• Build from within the ZMK repository using a command like the following, pointing to this repository as an extra module:

west build -p -b reform -S rp2-boot-mode-retention -- -DZMK_EXTRA_MODULES="/some/path/zmk-mntre-module"

With ZMK Studio support enabled:

west build -p -b reform -S studio-rpc-usb-uart -S rp2-boot-mode-retention -- -DZMK_EXTRA_MODULES="/some/path/zmk-mntre-module" -DCONFIG_ZMK_STUDIO=yes

Additional snippets can be added to build for either the MNT Reform Classic or MNT Reform Next mode:

• -S reform-classic
• -S reform-next

Custom Behaviors

This firmware exposes two custom behaviors to provide the full functionality expected for an MNT Reform laptop keyboard.

These are bound to keys matching the original firmware, but can be freely rebound to any key in code or via ZMK Studio.

• Reform Menu - Code binding: &reform_menu
  • This is bound to the Circle key by default, but can be re-bound to anything
  • Provides an interactive menu to basic keyboard functionality (RGB, Reset, Flashing, Reform System Control)
  • Menu is navigated using the arrow keys, select an item with enter.
    • These are keycode based, not physical layout based, and will respect any re-mappings.
  • Menu items can be invoked directly without navigating via their hotkey
  • NOTE - Be careful when removing the binding to the Reform menu and ensure you have bindings to it's functionality elsewhere
• Reform System Control - Code binding: &reform_sysctrl
  • Parameters are provided in #include <dt-bindings/zmk/reform_sysctrl.h>
  • &reform_sysctrl R_PWR_ON - Sends system control command to power on laptop
  • &reform_sysctrl R_PWR_OFF - Sends system control command to power off laptop
  • &reform_sysctrl R_WAKE - Sends system control command to wake the laptop
  • &reform_sysctrl R_BATT - Sends system control command to retrieve battery state and renders it to the OLED
  • &reform_sysctrl R_STATUS - Sends system control command to get firmware info and renders it to the OLED

References

• MNT Reform Shop link for this keyboard
• Official Firmware Source
• Keyboard PCB Source
• Keyboard Schematic

License

SPDX-License-Identifier: GPL-3.0-or-later