By the way, the 6502 (yay Commodore 64!) has something like a microcode: a PLA. This describes it a lot better than I ever could.

https://news.ycombinator.com/item?id=5353198

Visual 6502 made me understand my Commodore 64 in an unexpected deep level. I experienced epiphany and bliss: I can begin to understand how computing works from GraphQL down to electrons.

http://www.visual6502.org/JSSim/index.html