Through my documentation of Game Boy boards, I have drawn up schematics of each device. I know them pretty well. Check out my board scan wiki https://wiki.nataliethenerd.com/
I jokingly made this tweet when the kit was announced, but decided to actually do it.
I know from experience of routing Game Boy CPU PCBs that there isn't much to it. There's the RAM, CPU, some decoupling capacitors and power regulation.
Note: I went with the MGB (Pocket) CPU rather than DMG for a couple of reasons.
They are pretty much the same
I have more of them
They are cheaper and easier to get. This opens up the project to more people
The DMG CPU has external VRAM, the MGB CPU has internal VRAM and in a very space conscious build that was the biggest factor.
DMG motherboard. Image source: Rodrigo Copetti https://www.copetti.org/writings/consoles/game-boy/
Pre Planning
I only had the press pictures to work off. I used the dimensions to scale the image on my PC and from that I got measurements for the screen inserts; since that's where I plan to put the Game Boy.
I incorporated the power circuit I use for my Safer Charger boards, changed the power switch to a soft latching power button, added pin outs for the button matrix and audio.
KiCad 3D renders of the PCB
I didn't really know what the buttons on the Lego would be like, but the fact that they could be pressed was enough for me to know I could implement them. At the moment I have them wired up to custom 3D printed *toy brick* parts. Same with the USB C
0:00 / 0:07 1× Clicky buttons!
I am currently working on refining the board now I have the Lego build in my hands. This project will be released in full once I am finished with it - so stay tuned!