K-202 was later developed into MERA 400, which was somewhat more successful. https://mera400-pl.translate.goog/Strona_g%C5%82%C3%B3wna?_x... One of interesting things from modern perspective is that these machines didn't have synchronous clocks, but cycles were timed by RC delay circuits which were tuned differently for various groups of instructions. One notable operating system developed for it was CROOK, which was significantly more unixy compared to other contemporary mainframe based systems. There's modern emulator for it https://github.com/jakubfi/em400, and they have excellent YouTube channel (in Polish though): https://www.youtube.com/@MERA400/videos