Gecko keyboard

Somewhere between the corne, and the sofle.

Adding several small thumbwheels, as full size encoders are too big.

The Gecko uses CRKBD as a base, Add a few extra keys to the bottom row, useful for mute / sleep etc, and find space one or more small wheel encoder.

Parts required

PCBAs

• These can be ordered through pcbway?

Based on the options available / cost, I went with back side only (only the USB is on the front), and missed both the Kailh Hotswap sockets, and the LEDs.

Parts list

Boards

• PCBA's, pair (see above)
• top plate, pair, 1.2mm
• Bottom plate, pair (or alternate case)

PCBA

• 2x USB Sockets (TYPE-C-31-M-13C)
• 2x audio sockets (PJ-398A-5A_PJ-399B-6A)
• 4x Scroll wheel encoders (EC05E) (optional)
• 46x LEDs (SK6812MINI-E) (optional)
• 2x OLED displays (optional)

Tools

• Soldering iron, fine tip, solder etc.
• Screwdriver for the bolts

Assembly

• M2 standoffs (min 8mm? ) x 10?
• M2 flat ended bolts, max length standoff height/2 x10
• 3 wire cable assembly(3.5mm male - 3.5mm male)

Keys

• 46 x Kailh hotswap sockets ()
• 46 x Choc V1 switches (any variety you like)
• 46 x Choc V1 keycaps (all singles is fine, or 2 x 1.5U)

Assembly instructions

Electrics

• Find parts
• Assemble PCBA's
  • Bottom side
    • install USB-C ports
    • install TRS connectors
    • install hotswap switch plates
    • install Mini-E LED's (optional)
  • Top side
    • install encoders
    • install OLED display

Mechanics

• Take a top plate and attatch M2 standoffs to it's bottom surface. (I use loctite)
• place the corner switches into the top plate
• add the PCB (care of the pins)
• Add the rest of the switches
• If you plan to use the tenting kit, add standoffs to the bottom of the bottom plate in the additional holes.
• place the bottom plate on the assembly, and tighten the bolts.

Programming

Now test that everything is working

• Recognisable on USB.
• All key presses etc.
• encoders
• LED's
• OLEDs,

Get the QMK firmware from (here) this is the keymap () follow programming directions (here)

Once you know

Known Issues:

• The encoder cutouts for the horizontal wheels aren't big enough - if you want to use them, you will need to modify the top plate.

• Always unplug the USB before the 3.5mm connector - the 3.5mm has the potential to short out the board, and fry the mcu.

Troubleshooting

Odds are, any issues will be in the parts you soldered.

If you can't communicate with an MCU to program it, it's likely the USB-C

If the two halves won't communicate, it's the TRS connectors or cable.

The LED's are often very fiddly, and I won't offer any guidance on them, they do not effect the usage of the keyboard, and are a tedious job to get working.

Programming

Flashing

Flashing is simple drag and drop. The tagged release that I currrently use is here On Windows

• Plug the keyboard half in.
• Reset if needed (hardware button, or a key combination)
• It should initialise as a RPi storage device
• Drag the firmware file to it (*.uf2)
• The window will close and the keyboard will reboot with the new firmware.

Configuring Firmware

The firmware uses QMK, My fork is located here Use the keyboard/gecko branch, or a tagged release to base changes on.

To build on Windows

Use QMK WSL

• get the git repo https://github.com/DaneEvans/qmk_firmware
• use the keyboards/gecko branch.
• qmk build -kb gecko -km devdev
• Navigate to the /Linux/QMK/home/qmk/qmk_firmware directory (Where QMK WSL resides)
• Copy the keyboard_xxx.uf2 file to the keyboard halves.