Ship #1 Pending review

@ReuTheNetizen on Stratum [Macropad] · about 2 hours ago

Stratum is a 9-key personal macropad creation with a rotary encoder, an OLED display and RGB backlighting under each key that uses QMK firmware. It supports five independent layers (Main, Productivity, Design, Scientific and Media), allowing each key to perform a unique function depending on the active layer. That’s how I came up with the name Stratum; it reflects the macropad’s ability to swap between distinct layers. It also has OLED screen sleep and LED brightness control.

The most challenging part of the building process was definitely soldering the LEDs due to how small they are. I was most proud of the fact that my design measurements and proportions had come out right so everything fit together quite well during assembly.

1 devlog
2h build
Hackpad

Video of Project → See source code →

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@ReuTheNetizen on Stratum [Macropad] · 4 days ago

2h 14m 6s logged

Building Devlog

Stratum is assembled and fully functionable!

This was my second time ever soldering in my life, so I had to do a bit of review before soldering. Fortunately, everything went smoothly once I had started soldering.

I started soldering the LEDs first so I had a completely flat surface to work on. I believe my first initial joints were cold, but I soon got the hang of putting on the pad to heat it up, adding the solder and removing it before removing the soldering iron, so I was able to fix up those joints. I do remember I also melted the plastic of one of the LEDS, but it still seems to be functional. Afterwards, I did the diodes, then the OLED, then XIAO RP2040 and lastly the rotary encoder. I got the hang of feeding the solder into the heated joint area pretty quickly. I honestly spent more time setting up the electronic components so it is in a good position to solder than actually soldering.

Once a small issue that did arise was that my OLED cutout was not big enough to allow the whole OLED to poke through the top plate. Although the screen is not blocked, this prevents switches from being able to fully stick itself inside the PCB hole. However, I was still able to (just barely) solder together the switch pins to the PCB. The connection is still strong, so my oversight was not disastrous. Screwing the case together was relatively simple. I also had an issue getting the XIAO RP2040 to connect to my laptop. Turns out almost all the USB-C cables in my house are for charging only, not data transfer.

I did not include this in the logged time, but when I first uploaded my firmware, the OLED displayed a static pattern instead of “MAIN” (the default layer). After a bit of troubleshooting I eventually figured out it was because I included a clear action in all of the function responsible for controlling my OLED display. I fixed this by removing it and adding a function that pads every line to full width (clearing previous text in the process) instead of clearing the whole buffer.

*FYI: I did all of my design work for the macropad during the Outpost event, so my design got approved using the form rather than on Stardance. To ensure my design hours don’t get added to my build hours, I just decided to make a new project dedicated to tracking my build progress.