3/9/2026 - Planning

I did some basic research on low profile keyboards and how they are designed. I decided to make a wired keyboard because it is easier to design and better for a small keyboard. I also chose a 75% layout because it has a good balance of size and keys.

After that, I did more research and set up KiCad again. I looked at different controller boards and first found the nice!nano. It looked good, but it costs about $30, which felt too expensive. Then I found the Supermini NRF52840.

I like this board because it has Bluetooth and built-in charging management, which makes the design easier and allows Bluetooth as an option. I also looked for a receiver dongle and found the nRF52840 Dongle. It works with ZMK, but it looks a bit bulky, so I may keep looking for other options.

3/10/2026 12:23 AM - Schematic

I finished the schematic. At first I planned to use two OLED displays, but after checking ZMK’s battery profiler i decided not to use them because they would reduce the battery life by about 7 times.

I made two separate matrices, one for each half of the keyboard. Each half also has its own microcontroller. This helps with better battery life and since the microcontrollers are cheap, this design is easier to build.

The reason this is considered entry level is because it has fewer keys, which can reduce efficiency. However i think it will still work fine. The PCB will also be much easier to design than the other one. I will need to start from scratch but I am okay with switching to this idea.

i have completed both of the sides as it wasn't much time taking becaouse both sides were almost similar.

3/10/2026 12:44 AM - Routing

The left-hand side PCB is finished. I’m happy with how it turned out. Designing the first keyboard helped a lot when routing this one, so the process was easier. Now I just need to copy the design for the right-hand side. After that, I can start working on the case, which I think will be the hardest part. tHis is taking a lot of time as i Don't have a proper setup and is taking a lot of time here.

Right Side is donw too , now i am gonna move to CAD part for which i most prob need to switch to another pc cuz mine one can't handle it .

3/10/2026 12:46 AM - Right

After a couple of hour sof procrastinating, designing the PCB in KiCad became too difficult. I couldn’t flip the keyboard to the right side because of how everything was arranged, so I got stuck and decided to switch to Ergogen.

Ergogen was not much easier at first because there was very little documentation. I spent a lot of time researching small things, so I will only count the time I spent actually working in the editor.

Right now I have about a 400-line config file that defines the switch layout, the PCB, and part of the case. I still need to add screw holes and finish wiring the PCB. Ergogen helped a lot and makes it possible to create a perfectly symmetrical keyboard.

3/10/2026 12:48 AM - CAD

Finished everything appart from firmware, it turns out that ergogen doesnt generate the other half of your keyboard! This was really annoying and i had to flip positions in kicad using a script i found. But finally after all the issues the case is done with its correct cutouts and both halfs of the pcb are wired and filled correctly!

3/10/2026 1 AM - FirmWare !

I did this just after PCB but forgot to Journal XD

It wasn't much difficult or timetaking to design the firmware . It is based on ZMK firmware and is quite new for me as It's my firsr ZMK project but overall was a Good Experience . I think this is my last Journal for this project , I re created this whole Journal as I faced a issue because my small brother knowingly deleted my project for a small revenge .
Also I did the Github work ,it took a lot of time as it was a big project.

3/18/2026 - Correction !

I made a mistake while creating GitHub repository that I gave CAD files in FreeCAD Files format rather than STEP files and also placed them in different subfolders .

Now I corrcted all my mistakes also I did journal a 2 of the last journals before time and added the images later , this was a mistake and I have corrected time now for each journal . In real it was 17h + in one day but honestly only on work , no troubleshooting it was like 13.5 Hours .

3/19/2026 - Corrections V2 !

Dumb me used Aliexpress links in the BOM which I forgot don't ship to India so I replaced those with The amazon links which made the project a little costlier but for a split keyboard 103 USD isn't much .