Yup, having an emulator for another, more complex architecture running on the very simple architecture is common amongst projects like this. Linux on Intel 4004

Yup, having an emulator for another, more complex architecture running on the very simple architecture is common amongst projects like this. Linux on Intel 4004 does exactly this: https://dmitry.gr/?r=05.Projects&proj=35.+Linux4004 https://dmitry.gr/?r=05.Projects&proj=35.+Linux4004 And its predecessor project(s) do as well. Usagi's UE-1 was already mentioned as another vacuum tube computer. It indeed just runs instructions in a loop, and runs every instruction in each loop (but not every instruction is always effective).