Pie Board

Created by [SbRhubarbPie] • Started on May 23, 2025

A custom 100% keyboard

Total time spent on project: 89hr

May 23, 2025

Started going through lots of videos and threads to find ideas for parts and general ideas of what I might want to do for design. I found some cool keycaps that look like a sunset, and based on the color of RGB blacklighting they can look interesting.

71nxtxnoUIL _AC_SL1500_

Found and went with what are supposedly one of the best budget linear switches (Gateron Milky Yellow), as well as decided on going for a 100% keyboard even if it may be more challenging because I like my numpad.

Total time spent today: 3hr

May 24, 2025

Started going through tutorials and threads to find a suitable micro controller. I ended up going into a rabbit hole on directly soldering the chip onto the pcb and all the curcuits I would need for that. Althogh I learned a lot about this, I really just lack the experience and tools needed to directly solder a chip onto the PCB, so I decided on using a devboard. I ended up settling on the STM32F411 blackpill because I need an excessive amount of ports to handle a 100% keyboard matrix with RGB.

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I looked into the general design of keyboards to get an idea of how I would want to CAD the parts out to be printed in parts, which seems doable but will take some time.

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Total time spent today: 6hr

May 25, 2025

I am revisiting what microcontroller to pick because I would to prefer to work with micropython. I found the rp2350 stamp, which is really nice and I might go with instead.

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Busted out the first step of the schematic (basic switch matrix, neoleds and pcb locations)

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Only partialy through the first routing but will 100% have to redo it at least a couple times

Total time spent today: 12hr

May 26, 2025

I finished routing all of the adressable LEDs, then had to start rerouting all of them over again (twice) because I used the wrong footprints, which cost me a lot of time. I also researched data resistors for the LED strand which is very interesting and looked into usb c options abd routing.

Total time spent today: 7hr

May 27, 2025

Added USB c, and an encoder, then researched and added a level shifter for my LED data line as well as making smaller changes and finishing routing.

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May 28, 2025

Fixed multiple small issues, implemented ground fills and did overall polish

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Researching how to implement fuse and ESD protection and starting work on the case Total time spent today: 6hr

May 29, 2025

Redid my routing again to implement a duplex switch matrix and added the ESD and fuse protection. Routed data lines as a differential pair once I realised it was important. I think I am mostly done with the PCB and will start to focus on the case.

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Total time spent today: 8hr

May 30, 2025

Started building out the keyboard in fusion 360

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Total time spent today: 5hr

June 1, 2025

Redid the pcb power routing and changed some components so I can only order off of one website. PCB is ready for order. Continued to work on the case.

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Total time spent today: 14hr

June 2, 2025

Continued work on the case, researching how others have made 3d printed plates as I do not want to pay for metal. I am working on implementing a 3d printed nonslip TPU pad on the back.

Total time spent today: 4hr

June 3, 2025

More work on the case, I looked into adding an OLED screen but decided against it.

Added magnetic tpu feet as well as a logo plate sandwitched between the two bottom peices

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Created the cutout for the USB port

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I think I am getting close to finishing, will have to code and then review everything.

Total time spent today: 7hr

June 4, 2025

Ultimately revisited the OLED screen, I am going to implement a ssd1306 screen here. trying to figure out how to fit it in, might have to desolder the pins

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looking at connectors I can use to get off the pcb

Total time spent today: 4hr

June 5, 2025

Went to a peach pit concert :)

June 6, 2025

Spend a lot of time looking at options for attaching the screen, but I have just ended up deciding to hand solder it with wires instead of using any connectors to keep it simpler. I then fixed the pcb to reflect this

Total time spent today: 4hr

June 7, 2025

Finished implementing the screen into the case

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I did this by pushing it off the middle plate with pins so that way it is easily adjustable without reprinting an entire major part and to make production easier.

Total time spent today: 3hr

June 11, 2025

Over the last few days I have been really busy attending tons of friends grad parties and finishing up the end of the year. I was able to code most of the firmware with small amounts of spare time here and there but did not really have the time to journal everything (if you are interested you can look at the commits). Today I finally had some time and have started to pull together all of the final files into the github. Looking at the BOM it is gonna be pretty expensive so I am currenty looking into removing the rp2350 stamp devboard and directly SMD mounting one instead.

Total time spent today: 6hr

June 12, 2025

I have decided that I will stick with the rp2350 stamp, building a controller directly into the keyboard seems like a fun project on its own and I now want to do something like that as a future project, but I am going to limit the scope of this project to prevent myself from going into the deep end and possibly having too many problems as this is one of my first pcb projects. I am continuing work with getting all my requirements for Highway submission.

Attended Zack Freedman's AMA while I finished uploading everything to the github.

Total time spent today: 4hr

June 20, 2025

added decoupling capacitors for the neopixles, ordering parts

Total time spent today: 2hr