What did I done learn?
Well, I feared this project beyond my capabilities for the most part and the manuals being in Russian didn’t assuage that. It was only thanks to the wonderful MS6205 library and kind words from a stranger to get me through.
I learnt that certain ICs can be more finicky than others. Specifically the shift register caused me some grief, and I genuinely don’t know how I fixed it. The angry pixies are barely contained in that one.
If I were to do it again, I’d fork out for the plug socket and wait for international delivery rather than soldering it all up myself (because it’s less risky and, you know, easier) but I’m impatient, so.