Fang, Claw and Knight’s WEE FORTRAN – retrocomputing ephemera

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/

#RetroComputing #PicoMZ80K #PicoMZ80A #Sharp

The Pico MZ-80K – retrocomputing ephemera

New from me: Calculating the date of Easter Sunday for all years from 1753 onwards ...

https://z80.timholyoake.uk/happy-easter/

#RetroComputing #BASIC #SharpMZ80K #PicoMZ80K #Easter

Do you know when the next lunar umbral eclipse is?

The Pico MZ-80K running program 9 from Celestial #BASIC does!

https://z80.timholyoake.uk/celestial-basic-lunar-eclipses/

#RetroComputing #Sharp #MZ80K #PicoMZ80K

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/

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.

#RetroComputing #PicoMZ80K #PicoMZ80A

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!

#RetroComputing #PicoMZ80K #PicoMZ80A

Just looking at how straightforward it would be to extend the Pico MZ-80K to emulate the MZ-80A as well.

Shouldn't be too difficult, and it could potentially run CP/M.

I've a feeling I'm just about to fall down a rabbit hole that I swore I wouldn't ...

#RetroComputing #Sharp #MZ80A #MZ80K #PicoMZ80K

Pleasingly the #PicoMZ80K also works with the #RC2014 pico based VGA terminal with the addition of an external micro sd card reader and speaker. As I've used the ground on the expansion header for the sd card, I've borrowed a ground from the unused tx/rx pins for the speaker :)

Will be in my repo later once I've tidied the code up ...

#RetroComputing #SharpMZ80K