_Build Your Own Z80 Computer_ by Steve Ciarcia is fantastic. You will learn the basics of computer architecture, digital logic, assembly language, power supply design, and a basic operating system. Even though it's a book from the early 80s using chips from the late 70s the parts are still available.I believe the author has posted a pdf of the book on his website, but there are used copies on Amazon and Ebay and it's a lot of fun doing a project like this without using the internet by relying on nothing but the paperback and a mouser catalog. https://www.amazon.com/Build-Your-Own-Z80-Computer/dp/007010... https://archive.org/details/BuildYourOwnZ80ComputerSteveCiar...

Interesting. I just got interested in going the 8-bit retrocomputer route, as I've always wanted to learn the low-level hardware stuff... down to the level of the CPU, the data bus, memory bus, I/O support chips, accessing RAM, keyboard interfacing, etc. So, to that end, I just decided to build a Z80 based microcomputer.

Somebody asked "why z80 and not 6502 (or 8085, etc.)" I guess the 6502 is a fine choice, but my subjective perception is that - out of the popular processors from that era - the z80 is the one that still has the most actual commercial applications, and is the one that is easiest to source, find up to date information on, etc. Maybe I'm wrong, but so far it seems going the z80 path is pretty accessible. I was able to source chips from Jameco with no problem (and they're pretty cheap), and the z80.info site has a ton of useful info on homebrew z80 machines[1].

I was also able to pickup a copy of the book "Build Your Own z80 Computer"[2] by Steve Ciarcia, which should help a little.

Anyway.. not to take anything away from the 6502. If it turns out that chips are available, I may take a stab at building one of those after I do this z80 thing. But for now, this feels like the "path of least resistance". But I'd love to hear about anyone else's experience building an 8-bit machine, regardless of which processor you chose.

[1]: http://www.z80.info/homebrew.htm

[2]: https://www.amazon.com/Build-Your-Own-Z80-Computer/dp/007010...