loongcat40

A 4x10 gasket mounted keyboard featuring a large OLED. A culmination of 5 years of learning.

Get PCBs here if you're in the EU!: https://keycapsss.com/Loongcat40-PCB/KC10265

status

• v0.1 pcbs have been produced but not yet tested.
• v0.0 pcbs have been produced. v0.0 has been been tested.
  • The keyboard largely works, though GPIO20 requires an external pullup resistor. This may have been due to the rp2040 dev board I was using.

about

case

All of the case files you need can be found in the case directory.

pcb

You can find the PCB source files in the pcb folder. The BOM files can be found in this folder.

directory structure

• case You can find the files you need in this folder to print out a case for the keyboard
• drafts Stores any KLE or intermediate information used in making the case
• pcb Kicad project relating to the project

BOM

• 1 PCB
• 40 hotswap sockets
• 40 diodes
• 1 2.08" OLED LCD (SH1122)
• 3mm poron gasket strips (80mm x 3mm x 4mm)
• 1 Raspberry Pi Pico 1
• 3D printed parts
  • 4 TPU oled standoffs
    • used to make sure that the oled is aligned when soldering
  • 2 PLA plates
  • 1 PLA case bottom
  • 1 PLA casetop
• 12 5mm M2 screws
• 4 rubber bumpons

assembly

• Assemble the PCB without the oled
  • the Pico should be soldered via castellated pins. Male pin headers should not be used
• Put the 4 TPU oled standoffs onto the oled module. These standoffs will help align the oled
• Solder the oled to the pcb. The oled module should be on the other side of the board such that it's on the opposite side
• Put the poron gaskets onto the plate
• Put the keys through the plate and onto the PCB
• Put the PCB onto the top of the case
• Put the bottom of the case on
• Screw in the bottom of the case
  • Note that screwing the screws for the first time may take some force, as the screws will be threading the plastic of the top
• Put bumpers on the bottom of the case
• Done!

firmware

You can find the QMK firmware for this project here: https://github.com/ChrisChrisLoLo/qmk_firmware/tree/loongcat40

acknowledgements

Thank you to NextPCB and all of my Github Sponsors for sponsoring and supporting this project!

Big thank you to @suh_ga for the fantastic artwork used and displayed on this keyboard! Please check her out at https://twitter.com/suh_ga!