Amosisbcrist/Amosis
40% Keywell Keyboard
Amosis Keyboard
The Amosis is a 40% split keywell board with a Cirque trackpad built into each side. The case is 3D printed, and features a keywell shape similar to Kinesis or Dactyl keyboards, except with only three rows.
Controller
This keyboard uses custom controller firmware written from scratch in Zig, and running on an RP2040.
It does not have runtime-swappable layouts or configuration. Instead, the keyboard layout, layer switching logic, mouse sensitivity, etc. is baked into the firmware, but updating the firmware is just a matter of holding the BOOT button while pressing the RESET button, then dragging a UF2 file to the RPI USB drive.
All of interesting configuration/layout stuff is handed in the logic.zig file. It should be relatively easy to customize the layout, though if you want to make behavioral changes, you will likely need to know some Zig.
The default layout is based on Hands Down Gold. The exact details can be found here.
It would probably be possible to use something like QMK with Amosis controllers, but please don't ask me to help with that; I have no interest and little experience with QMK, ZMK, etc.
Trackpad
Each side of the keyboard integrates a 40mm Cirque GlidePoint trackpad from a Steam Controller. While Valve stopped producing Steam Controllers years ago, you can still purchase the trackpads from Mouser, but you will likely need to make some modifications to make this work:
- There are several sizes available; the Steam Controller uses the largest 40mm size (TM40040), but you could use a smaller one if you adjust the case design.
- The retail Circues offer several options for plastic overlays, but the Steam Controller used custom overlays, so you may need to adjust the case design for your chosen overlay style.
- There are (or were) both SPI and I2C versions available. The Steam Controller only uses SPI, so you'll need to adjust the firmware if you want to use an I2C version (though I think you can change it just by adding/removing a resistor on the Cirque board). The SPI versions have part numbers TMxx0xx-2024 while the I2C versions have part numbers TMxx0xx-2023. At time of writing, it appears Mouser no longer carries the I2C version.
- The Steam Controller uses a customized connector pinout that's different than what's documented in the datasheet for the retail version. You'll need to adjust the schematic board layout to accomodate this.
- An Alps Haptic Reactor force-feedback element is glued to the back of the Steam Controller version and its power is routed through the same FFC cable. If you buy this separately, you'll have to figure out how you want to connect it to the board.
Building
Have the controller boards manufactured using the files in the kicad/gerbers/left/ and kicad/gerbers/right folders.
Ensure dependencies are available on your path:
Adjust the keymapping and layer logic as you like, then run zig build.
3D print a case using zig-out/bin/left.stl and zig-out/bin/right.stl.
Flash the zig-out/bin/firmware.uf2 and to both controllers (the same file can be used for both sides because the firmware will detect which side it is at boot).
Wiring
The 3 row signals are driven to 3.3V when scanning a row, and 0V when not scanning that row. The 7 column signals are read as inputs with weak pull-downs, and treat a high value as indicating that a switch is pressed. Therefore, there are 2 possible ways to wire the diode/switch matrix that will work:
- Diodes between the row signals and the switches, with a common anode for each row.
- Diodes between the column signals and the switches, with a common cathode for each column.
Note the line on diode packages indicates the cathode side. Also note while the schematics list a schottky diode part number, any general purpose diodes will work fine for the matrix, e.g. 1N914/1N4148, 1N4001, etc.