[Ted Fried] wrote in with now not one however two (2!) new drop-in replacements for well-liked old-school CPUs: the Zilog Z80 and the Intel 8088. Either one of the “chips” run in cycle-accurate mode in addition to in an excellent turbo mode, which will run so rapid that you simply’ll want to use the Teensy’s inner RAM simply to take care of.
Either one of those designs have a {hardware} and instrument part. The PCBs principally adapt the pinout of the Teensy to the objective CPU, with a host of 74VLC latches on board to do the voltage degree conversion. The remainder is an issue of emulating all the directions at the Teensy, which is extra than rapid sufficient to take care of. If this sounds acquainted to you, it’s principally the similar way that [Ted] used final 12 months to deliver us his substitute for the 6502 discovered within the Apple ][ and Commodore 64.
Why would you want an emulated CPU when the originals are still available? [Ted] inherited a busted Osborne I, an historical Z80 luggable. By means of changing the unique Z80 along with his emulation, he may diagnose all the machine, which led him to find some unhealthy DRAM chips and get the outdated beast working once more. Or possibly you simply wish to play IBM XT video games at insane speeds?
And it looks as if [Ted] has up to date his 6502 emulation to incorporate the undocumented C64 opcodes, so if you happen to’re into that scene, you will have to be coated as smartly.
If any of this tickles your fancy, head over to [Ted]’s weblog, microcore labs, and apply alongside. Even supposing now that he’s coated many of the well-known retrocomputers, we need to ask ourselves what processor goes to be subsequent?
