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A #cyber vet who wears a blue hat, a prog rock fan with ELP in his heart and a #TRS80 fan/collector and UK archivist.

After much testing and code comparison, the new Feb 2025 Release of #Vezza - my #z80 high speed #zmachine is ready! Took way longer than expected to synchronize across all of the code bases, particularly making sure that all optimizations made it across all platforms - TRS-80 model 1, TRS-80 model 3, TRS-80 model 4, the CP/M versions (~18 platforms), the embedded versions (Spectrum tape, TEC-1G), and slowly pushing into the Agon Light version (which has even more updates still in progress). Lots of individual tweaks, and some major rethinks and rewrites have come together to accelerate game play.

The hardest part of rewriting in this update involved rewriting the dictionary search code. I ended up going back to the original jzip interpreter, written in C for Unix waaay back when. Jzip provided much of the logic that went into ZXZVM, which provided the base for #M4ZVM #M3ZVM and #Vezza. Going back to Jzip made sense as Jzip has an even longer history; and is highly tested and stable and still maintained. This research gave me the confidence that the streamlining and changes I was making to such a fundamental part of the game would work, making all inputted dictionary searching more efficient.

To work around how CP/M stores executable files I spent a lot of time re-organising the memory map to make the executable smaller. This involved rearranging where the initialization code was stored inside the increasingly complex layout. Support across multiple versions means I needed to break up variable sized code and strings to sit inside variable sized gaps, while still compiling all the CP/M versions from the same interconnected set of source files. It needed quite a few manual checks to ensure that it all worked.

What this all means is that your favourite #infocom #punyinform and other text adventures will all play on your favourite z80 #retrocomputing platforms even faster than before!

More details in the devlog and downloads can be found at:
#TRS80 versions https://sijnstra.itch.io/m4zvm
#CPM #CPM80 versions https://sijnstra.itch.io/vezza

M4ZVM by sijnstra

Z-machine Infocom interpreter for the TRS-80 model 3 & 4

itch.io
@DosFox manufacturing issue or design issue?

@gmc a TRS-80 with an expansion interface will boot to crap on the screen as its trying to boot the floppy disk.

Hold <BREAK> and turn it on.

I'm not sure if this is going to work as my first public post with zero followers but... I have some old RAM modules that may be of use to someone?

DIMM
- kingston KVR400X64C3A/256
- apacer 256MB PC133 ECC
- micron 128MB PC133 ECC

SODIMM
- samsung 1GB PC2-4200
- hynix 512MB PC2-5300 (x2)

Let me know and we'll arrange something. These are located in Slovakia, Europe btw. Posting them anywhere in Europe should be easy and you can buy me a coffee if they work. 🙂

#retrocomputing #parts

@brouhaha #retrocomputing any clue on a programmer. My Dataman 48Pro2 can only read them!
Any able to programme an Intel 8041? My Dataman 48Pro2 can only read them. #retrocomputing
@brouhaha many thanks! I'll see if the #backbit team can add it #retrocomputing #fluke
I've some of these chips which I got from Ebay a while ago. I *think* they are actually Intel P8041AH's but marked as shown. Can anyone confirm as I can't Google a result. #retrocomputing #intel
Wrangling a NOS VfD display into my Flue 9010a display clone board. Keyboard is built and the main board also well on its way. #retrocomputing
I've seen things you people wouldn't believe. Dial-up BBS's written in BASIC. I heard 300 baud handshakes over an analog line. All those moments will be lost in time, like tears in rain. Time to log off.