Frost
Frost: Journal
Total time: ~34 hrs
May 31: 5 hrs 43 min
During this session, I did a bunch of research, made my schematic, and began my pcb!
My Research:
- Switches - MMD Princess Tactile, 48g. Thocky but tactile, budget friendly
- MCU - Nice!Nano v2 for easy bluetooth and battery support. Has a lot of cheap knockoff versions on aliexpress
- Keyboard Size - 75%, 81 keys - nice!nano only has 18 exposed pins so i removed 3 switches and put the mcu there. Less space needed as well since i can tuck the tiny battery under the mcu!
- Case and fastening - screw the pcb to the case. simple and inexpensive
- Plate - Nope, direct pcb mount. Looks cool, and i can do it all in white(matches my sister's desk color scheme)
- Stabilizers - Cherry Stabs (Clip in, PCB Mount, from KBDFans)
- Battery - 110mah, aliexpress - fits under MCU
- Hotswap Sockets - kailh hotswap sockets from aliexpress
- Diodes - THT, easier to solder
- Keycaps - cheap $17 set from amazon
| Item | Cost |
|---|---|
| MCU (nice!nano v2) | $25.00 |
| Battery (110mAh) | $3.00 |
| Switches | $19.30 |
| PCB | $59.00 |
| Stabilizers | $9.50 |
| Hotswap Sockets | $0.99 |
| Fasteners | $3.48 |
| Diodes | $2.34 |
| Keycaps | $16.99 |
| Total | $139.60 |
Links:
MCU: https://bit.ly/43MxEzh (Free shipping, $25+) Battery: https://bit.ly/4mHn5pD (Free shipping with mcu) Switches: https://bit.ly/4dSzwen Stabilizers: https://bit.ly/3FuRC9E Hotswap Sockets: https://bit.ly/4dIZlgY Fasteners(3.2mm diameter on the heatset inserts, m2 heatsets and screws): https://bit.ly/43L1Xq4 and https://bit.ly/3Zae3aP Diodes: random aliexpress brand, doesnt matter which one Keycaps: Any
Since the n!n has only 18 exposed pins, I'm going to do a 9x9 matrix in the schematic and drop 3 switches from a regular 75% layout and put my MCU and logo/name there.
Update - I just finished for today. Schematic is done, and pcb started but barely. Had to go back because I forgot the diodes though.
Here's what the schematic looks like(after I added the diodes):
Jun 1: 9 hrs 38 min
Did all the organizing, layouts, and wiring today! PCB is now fully finished, and it looks good. I added a snowflake icon since it's called Frost. It's looking amazing! Took a long time and looks a bit messy though because the schematic and pcb wiring diagram differ a bit - 9x9 vs 6x15. Also added stab holes and case attatchment holes. I used over 200 vias and over 1100 track segments!
Here are some images of the process and final renders:
Jun 2: 7 hrs 19 min
Made my ZMK code but stuck on an issue in GH Actions where it says it can't find my shield. Made a new repo for my zmk code though - frost-module as per the zmk docs.
Took a LONG time to learn ZMK. There are very few tutorials and explanations online, and the docs are somewhat unclear and they contradict themselves a bit too.
Jun 3: 2 hrs 4 min
Worked on that error. Asked online but the people's suggestions didn't work very well. Also asked Gemini but it hallucinated a LOT.
Jun 4: 8 hrs 9 min
Someone else responded to my discord post in scottokeebs server, and pointed out an error in my module.yml where I put board_root: .. instead of board_root: .
Then I worked on other errors, since there were lots of issues with my overlay and keymap.
Eventually, and with a bit of help from Claude Sonnet 4, I managed to produce a working copy of the firmware! It's available in /firmware - both the .uf2 and the full uncompiled version.
Also started the case in Fusion 360 - it's going to be a very simple design since I want the pcb fully exposed. That way the signal strength from the nice!nano isn't impacted at all.
Jun 4: 35 min - in the call!
Finished the case! It's pretty simple - here's an image:
Also applied for the 1 point bonus!