If you want to play with my Pico MZ-80K/A emulator, this weekend is a good time to buy the hardware from Pimoroni as there's 50% of their VGA demo base and 25% off a Pico 2. A MZ-80K and MZ-80A for less than £15!
More info on the emulator here: https://z80.timholyoake.uk/the-pico-mz-80k/
This is making me happy today - I've made good progress on listing and printing the contents of Sharp #BASIC programs using an authentic-looking font.
#PicoMZ80K #PicoMZ80A #RetroComputing
https://z80.timholyoake.uk/displaying-sharp-basic-programs-on-modern-computers/
More progress on the #PicoMZ80A extension. Keyboard handling done, all of the 0xExxx addresses implemented, screen works in A (2k scrolling VRAM) and K (1k fixed VRAM) modes. Code is uglier than it needs to be, but plays "duck shoot" nicely 😱
Choosing the emulator (K or A) at Pico power on to do, along with the A's reset button as well as dealing with some other peculiarities of the A that aren't in the MZ-80K.
A little bit of progress today ... Keyboard handling is now mostly sorted. Next job is probably to look at the additional 0xE0nn addresses that the #MZ80A uses for various things, including reverse video and screen / VRAM scrolling.
Here's an interesting "feature" of the MZ-80A monitor ROM. Depending on whether the screen is addressed by the monitor or 'poked' to from BASIC, some ASCII codes have a different effect.
It's most noticeable (at the moment) during emulator startup as the monitor is attempting to clear the screen by scrolling it downwards (Sharp ASCII 104). But my emulator assumes you are 'poking' 104 (0xCF) ... which happens to be a face in the Sharp display codes.
Should be easy enough to craft a fix, as I know where the program counter is when the vga display routines are called. I think!
Tim Holyoake