IMHO, if you want to learn by building emulators, I'd suggest working on video game emulation. If you go back to NES or similar, you won't have much modern info

IMHO, if you want to learn by building emulators, I'd suggest working on video game emulation. If you go back to NES or similar, you won't have much modern information, but it's a well trod path with lots of information available (some of which happens to be accurate and correct and useful). Much of it is not too complex, so you can make progress starting out, and you can bail out whenever you want, because if the world doesn't get another complete NES emulator, it's not a big deal. If you enjoy what you're doing, but want to learn about more modern CPUs and modern GPUs, you can progress towards more recent systems. The sixth generation systems (Dreamcast, PS2, Gamecube, Xbox) are comparable to modern architectures, but with a lot less horsepower. The NESdev Wiki is a good source of information [1] to get started. [1] https://www.nesdev.org/wiki/Nesdev_Wiki https://www.nesdev.org/wiki/Nesdev_Wiki