#vezza — Public Fediverse posts

Fellow #infocom text adventure fans, the newest #Vezza #zmachine #interpreter is now available for the #Amstrad #NC200 running CPMish. Using the glorious built in LCD display at 79x18 characters, it was a lot of fun to build. Special mention to Matthew Logue for not only requesting the NC200 version and providing platform information, but also for sending me a huge amount of photos from real hardware so I could debug, and doing a complete play though of Hitchhiker's Guide to the Galaxy to prove it worked.
#retrogaming #retrogaming

As a surprise Christmas gift to #retrocomputing, I've pushed out a new version of my #Vezza #Infocom #zmachine #interpreter. This time it's a #CP/M build, specifically for the #TRS80 models 2/12/16... on glorious 8-inch floppies. My requestor and tester Ziggystar12 was kind enough to take a photo of Bureaucracy running on a machine with the 8-inch drives; a game that could never be run on that machine before even though it was contemporary! #retrogaming #retroBattleStations

Another fine #z80 machine is the Tiki-100, hailing from Norway and running an OS that was compatible with #cp/m 2.2, called TIKO. This one has a pixel-based display which is rendered by the character out BDOS calls, making it a little slow, but still a lot of fun to work with. The boot disks and emulator are all Norwegian which was a fun challenge. The testing process also uncovered that the emulator has a timer bug, so the timing is different to that on real hardware. In the end, it all worked rather well. I ended up using the one colour highlight available to simulate bold text, bringing my #Infocom #Inform #Z-machine interpreter #Vezza to yet another machine. Download the binary from https://gitlab.com/sijnstra1/vezza

The Grundy #NewBrain was an interesting #z80 based machine from 1982. One of its more remarkable features was a built-in single line display in addition to the video out, allowing for some portable use. The machine was targeted at business use and didn't get a large amount of platform specific software. It ran a version of #CP/M 2.2 with an efficient implementation giving it a large TPA. The platform also supports inverse characters, although without a specific control code to toggle so I need to manually track reverse character mode and toggle the top bit accordingly. With some gymnastics in memory management, a 50Hz timer is available, allowing me to count the ticks for the 10Hz timer expected by a full featured #Zmachine
Now that it's properly tested and running, you can download the latest addition to the #Vezza family from https://gitlab.com/sijnstra1/vezza and if you are curious about the NewBrain you can get the emulator and other info from https://newbrainemu.eu/new/

I've attached screenshots of the Bomber game in action, as well as the #Infocom classic A Mind Forever Voyaging.

While porting #Vezza for another #z80 platform (the Grundy #NewBrain), I noticed that there was an issue with the timer routine for the #MSX version. It turns out that the code was in there for the MSX version was using the MSX clock, however, it was not calculating the time properly, The MSX has a fine-grained timer which allows me to measure the time to the nearest 0.1 second as required for the #Zmachine standard. This makes the MSX version one of the few that I have written which supports the full fine-grained time requirement.

While for normal text adventures, this timer resolution might not make much difference, some of the fun post-#Infocom games, this distinction is used. One of the games that I've tested which works properly now is the `bomber.z5`, a real time game where you need to drop bombs from the plane to create a flat landing for your plane. Check the screenshot below for the action! Download the latest from https://sijnstra.itch.io/vezza
#retrogaming #retrocomputing

Back to fun platforms to port my #Vezza #Infocom #Zmachine interpreter - this time it's the Enterprise 128. A 4MHz #z80 machine from the mid 80s, it has a great emulator, and a bespoke DOS known as IS-DOS, with a lot of compatibility with both CP/M 2.2 and #MSXDOS. While it needed quite some tweaking, a lot of the heavy lifting was done with my original #MSX version before it was optimised. As I understand, the #Enterprise128 didn't have a great library of games for it, so hoping this helps! Get it while it's hot at https://gitlab.com/sijnstra1/vezza Screenshots are the IS-DOS 1.0 version running Border Zone, and the IS-DOS 1.1a version running Beyond #Zork.

Another wet weekend, another #Vezza release! I was asked to adapt my #Infocom interpreter to another platform - this time the #SinclarQL. An interesting request as it uses a #Motorola 68008 CPU, however, it does have the ability to emulate a #z80 on #CP/M. I was given some pointers on which versions worked to some extent, along with some documentation. Fast forward a few days and I had adapted one of the VT52 versions crossed with other features, and now #Sinclair QL users can enjoy in CP/M mode their #Inform #ZMachine adventures. Yes, there's a native terp as well, however, this was only a few days worth of massaging to get it to work on the SUCCESS CP/M Emulator - the proof is in the screen shots. You can download the executable here https://gitlab.com/sijnstra1/vezza/ #retrocomputing #retrogaming

I've released a new version of my #infocom #z-machine #textadventure interpreter #Vezza for #CP/M and #M4ZVM for the #trs80 Model 1/3/4. There's some speed improvements, along with a reduced footprint (smaller file, more space for cache), and a bugfix for a rare edge case in error handling discovered through the release of Ghosts by @8bitgames
Disk images at https://sijnstra.itch.io/m4zvm and https://sijnstra.itch.io/vezza (with links to more platforms etc) #retrocomputing #cpc #msx #kaypro #osborne