I'm writing this the day before Easter Sunday 2025. In AD 325 at the Council of Nicaea, Easter Sunday was decided to be the first Sunday following the first full moon on or after the spring equinox - March 21st. However, the Julian calendar had a year that was too…
I used my Pico MZ-80K emulator to create a version of the ECLIP program from Celestial BASIC by Eric Burgess. The code correctly predicts that the next lunar eclipse is due on 14th March 2025. I've tidied the output somewhat and there are clearly other optimisations that could be made.
I've been working on a way of displaying Sharp MZ BASIC programs from a digital tape file (mzf/mzt/m12 formats) on a modern computer. I've used a Raspberry Pi 5 as my daily driver for some time and it would be ideal (for me) to be able to look at, print…
With winter dragging on, I've had plenty of time to add the code needed for MZ-80A emulation into the Pico MZ-80K/A, as I'm now rather inelegantly referring to it. From a user perspective there really isn't a huge difference between the two machines. The most noticeable change on the real…
When I set out to create the Pico MZ-80K, I swore that I'd only attempt to emulate the Sharp MZ-80K and not the whole MZ range. But it is very tempting to extend the code I have to cover the MZ-80A as well. There's not a lot of difference between…
A new year and I'm back to tinkering with the Pico MZ-80K emulator. I've started work on support for the RC2014's RP2040 VGA terminal card. I'd not had very much luck with it last year, but I'm now making decent progress thanks to a closer examination of the picoterm firmware…
I've temporarily given up on the floppy disk emulation for the Pico MZ-80K. I've managed to get the read emulation working reliably, but not writing. I appear to be missing a status register flag that tells the controller to stop writing and where to restart ... but I haven't been…
The quest continues! The disk images I found a couple of days ago turned out not to be MZ-80K compatible ones (at least, not with the original drives and SP-6015 BASIC configuration) so I ended up back at square 1. Reading the SP-6015 Disk BASIC manual (the link goes to…