Shawn Sijnstra
sijnstra.bsky.social
Shawn Sijnstra
@sijnstra.bsky.social
I like technology - new, old and even older. Writing and porting my infocom interpreter (z-machine) to as many z80 machines I can find
http://gitlab.com/sijnstra1/vezza
Developing for the
Agon Light https://github.com/sijnstra/agon-projects
Reposted by Shawn Sijnstra
Time for another image viewer for #agonlight #console8 - this time, PCX format. There are a number of reasons why I chose to display this format on the Agon/Console8.
* It is an already existing format
* The format is supported by modern tools, including #gimp
* […]

[Original post on hachyderm.io]
January 11, 2026 at 12:28 PM
Reposted by Shawn Sijnstra
I recently took advantage of some temporary discounts and acquired the #console8 by Heber. It's a #retrogame focused package of the #agonlight, complete with some great joypads that they also make. As part of the induction into the house, I converted the logo […]

[Original post on hachyderm.io]
December 8, 2025 at 5:49 AM
Reposted by Shawn Sijnstra
Time for another programming option for the #agonlight family... #pascal! I've re-targeted PASTA/80, an open source Turbo Pascal 3 compatible cross-compiler that targets #z80 machines. It's still early days, so expect a lot of weirdness and issues, and things […]

[Original post on hachyderm.io]
November 24, 2025 at 9:18 PM
Reposted by Shawn Sijnstra
I wanted to use more graphics on my #agonlight and the best project that came to mind was to display #amstrad #cpc .pal/.scr images. Took a while to get there, and now it works including the same "wipe" effect that the original hardware had due to the unusual […]

[Original post on hachyderm.io]
August 26, 2025 at 12:26 PM
Reposted by Shawn Sijnstra
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 […]

[Original post on hachyderm.io]
May 31, 2025 at 1:51 AM
Reposted by Shawn Sijnstra
As far as I can tell none of the Infocom games for the NEC APC have been archived (they sold only hundreds per quarter, so not shocking).

Presenting… DEADLINE for the NEC APC, running on CP/M-86! #RetroComputing
May 31, 2025 at 2:54 AM
Reposted by Shawn Sijnstra
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 […]

[Original post on hachyderm.io]
May 31, 2025 at 12:59 AM
Back to porting my #Vezza #Infocom #Zmachine interpreter - this time for the #Enterprise128 - a 4MHz #z80 machine running IS-DOS, compatible with CP/M 2.2 and #MSXDOS. Download: gitlab.com/sijnstra1/ve... Screenshots are Border Zone and Beyond #Zork showing different IS-DOS capabilities.
May 4, 2025 at 10:39 AM
Reposted by Shawn Sijnstra
Get them at polyplay.xyz
April 30, 2025 at 9:26 PM
Reposted by Shawn Sijnstra
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 […]

[Original post on hachyderm.io]
February 11, 2025 at 11:58 AM
Reposted by Shawn Sijnstra
Now that it's had a little testing other than me (Thanks Brian Chiha!) I'm making my #vezza for the #TEC-1G more readily available, similar to my #zxspectrum .tap files. #zmachine text adventures for all #z80 machines! I've put up 3 sample builds to download […]

[Original post on hachyderm.io]
December 27, 2024 at 8:05 AM