Tim HolyoakeIt's escaped! The Pico MZ-700 is finally ready.
8253 emulation rewritten and games that use the MZ-700 joystick now work with the keyboard (I haven't got around to emulating a joystick!!) Almost there - need to re benchmark everything due to the nature of the changes I've made to the 8253 and 8255 code.
Hmmm. A number of programs aren't working correctly, and the common denominator is that they can all use a joystick. Looks like my 8253 emulation will need extending to deal with this, as on the MZ-700 sound and joysticks share the same addresses, but with different values being set on a counter that I'd kludged for the 80K/A emulations.
Soldering iron now found, Pico 2 headers installed (probably the worst bit of soldering I've done in ages, but it works) and tuning done for the MZ-700 and MZ-80A. Just the MZ-80K to go. I've spotted a couple of things I can easily improve and I need to check things like music tempo and pitch. I also need to work my way through some more software as I seem to have exclusively used S-BASIC, a prime number generator, space invaders and moonlander to date. Still hopeful at finishing a first release by the end of the month.
I think I may have found the weirdness in the keyboard handling today. Looks like I may need to rewrite my 8255 emulation as it could also be the root cause of my cursor blink speed issues. More investigation needed however. #RetroComputing #Sharp #MZ700 #PicoMZ
Running the emulator at 200MHz is a definite improvement - it's only 2 seconds slower than the real thing for the primes up to 10,000.
Sunday afternoon benchmarking session. A real MZ-700 vs my emulator. The emulator is currently 20% or so too fast when running on a 220MHz Pi Pico. Should be easy enough to slow down!!