[santadakota]

Ben Eater's fantastic video series on building a breadboard 6502 based computer and an 8-bit breadboard computer from scratch might be appreciated in this thread.

6502 playlist: https://www.youtube.com/watch?v=LnzuMJLZRdU&list=PLowKtXNTBy...

8-bit build playlist: https://www.youtube.com/watch?v=HyznrdDSSGM&list=PLowKtXNTBy...

He also sells kits if one is interested in playing along.

[AceJohnny2]

Highly recommend Ben Eater's video, which in this embedded developer's eyes has been the clearest, best explanation of the fundamentals of a CPU as I've ever seen.

[snvzz]

Similarly, I have come to appreciate rehsd's[0] efforts in building a 80286 computer.

0. https://www.youtube.com/@rehsd/videos

[rep_lodsb]

Wow, that series looks fascinating!

Only watched the first video yet, after initializing itself the CPU actually runs this code (because D8-D15 is wired to zero):

  addr    opcode
  FFFFF0  90           NOP
  FFFFF1  00 90 00 90  ADD [BX+SI+9000],DL
  FFFFF5  00 90 00 90  ADD [BX+SI+9000],DL
  FFFFF9  00 90 00 90  ADD [BX+SI+9000],DL
  FFFFFD  00 90 00 --  !! general protection fault

You can see it read and write the same address three times, then fetch the interrupt 0Dh vector and push flags+CS+IP to the stack :)