This is a simple handheld that uses ATmega328P as the processor. I wanted to create a tile based engine for the console, but I lack the skills to do that. I'll just make this open source and hope for the best.
You can find the PCB from here (public EasyEDA project): https://easyeda.com/laurilateemu8/k-sikonsoli-oled
More info in my blog (in Finnish): https://teukka.webnode.com/l/avoimen-lahdekoodin-kasikonsoli-ja-pelimoottori/