If you look closer, this CPU _is_ actually some roms sandwiched between registers. All the logic remaining are bus arbiters and IO access. You can replace 74-1

If you look closer, this CPU _is_ actually some roms sandwiched between registers. All the logic remaining are bus arbiters and IO access. You can replace 74-181 with one more rom though, but it will not decrease chip count... EDIT: actually if you replace 74*181 with rom, you can get rid of NZERO flag detection gates (minus 1 chip)...