Uploaded November 2025 | Updated September 2026, 3 weeks ago
Part 4 of my series exploring the Memorex VIS. In this part, I do an exploratory dive into interacting with VIS' video and hand control subsystems from within HaikuDOS using examples I wrote in assembly language and QuickBasic 4.5. I then take a look at what happens if you run unmodified PC titles on the platform (Prince of Persia, Might and Magic III, Ultima VI). Later, I walk through the exercise of attempting my first application port: Jeff Vavasour's Color Computer 2 Emulator, including pitfalls and issues. I demonstrate the DOSMON utility for catching incompatible INT 21H calls and the process for porting an application over. And finally, I dive into my VIS port of Commander Keen In Keen Dreams, which was written in C. Here in addition to addressing VIS incompatibilities, we deep-dive into the hand-control and integrating it into the game.
Music/SFX (in order):
SFX: Scrabble Tile Drop
Music: None.
Links:
Tandy's Licensing Utilities & VISBIOS.DOC - github.com/TJBChris/memorex_vis
Tandy Showcase's Main Site - tandyshowcase.com
tandyvis.com - Modular Windows Doc - tandyvis.com/media
Jeff Vavasour's CoCo 2 Emulator: cpmarchives.classiccmp.org/trs80/mirrors/www.vavasour.ca/jeff/trs80.html#coco2
Original Commander Keen Source Code: github.com/keendreams/keen
Modular Windows DOC and ISO (archive.org) - archive.org/details/microsoft-modular-windows-software-development-kit
Expand the "PDF" section for the PDF documents (Getting Started, Programming Reference, and Design Guide).
The ISO can be found via the "ZIP" link.
Chapters:
Intro (0:00)
Video Subsystem Discussion & Example (2:55)
Hand Control Subsystem & Example (13:41)
Running Unmodified PC Titles on VIS (21:12)
First Port Attempt: Color Computer 2 Emulator / DOSMON (28:46)
Porting Commander Keen in Keen Dreams (46:36)
Commander Keen Demo (1:15:27)
Outro / What's Next (1:23:16)
I do these videos unscripted, so I apologize if the in-the-moment descriptions of things are a bit scattered. If you have any questions/comments about this video, you can find me in any of these fine locations:
The Tandy Discord Server
The CoCo Nation Discord Server
The TRS-80 Color Computer (CoCo) group on Facebook
The CoCo Crew Podcast group on Facebook
On the Vintage Computer Forums (vcfed.org)
The TRS-80 Models I-4/4P Group on Facebook
Tandy / Radio Shack Model II /12 / 16 / 16B / 6000 Owner's Group on Facebook
X (I'm TJBChris there...)
Mastadon: TJBChris@mastadon.social
The Level29 BBS (I'm TJBChris there, too.)
Particles BBS (Guess who I am here? Yeah, TJBChris.)
Thanks for watching!
Part 4 of my series exploring the Memorex VIS. In this part, I do an exploratory dive into interacting with VIS' video and hand control subsystems from within HaikuDOS using examples I wrote in assembly language and QuickBasic 4.5. I then take a look at what happens if you run unmodified PC titles on the platform (Prince of Persia, Might and Magic III, Ultima VI). Later, I walk through the exercise of attempting my first application port: Jeff Vavasour's Color Computer 2 Emulator, including pitfalls and issues. I demonstrate the DOSMON utility for catching incompatible INT 21H calls and the process for porting an application over. And finally, I dive into my VIS port of Commander Keen In Keen Dreams, which was written in C. Here in addition to addressing VIS incompatibilities, we deep-dive into the hand-control and integrating it into the game.
Music/SFX (in order):
SFX: Scrabble Tile Drop
Music: None.
Links:
Tandy's Licensing Utilities & VISBIOS.DOC - github.com/TJBChris/memorex_vis
Tandy Showcase's Main Site - tandyshowcase.com
tandyvis.com - Modular Windows Doc - tandyvis.com/media
Jeff Vavasour's CoCo 2 Emulator: cpmarchives.classiccmp.org/trs80/mirrors/www.vavasour.ca/jeff/trs80.html#coco2
Original Commander Keen Source Code: github.com/keendreams/keen
Modular Windows DOC and ISO (archive.org) - archive.org/details/microsoft-modular-windows-software-development-kit
Expand the "PDF" section for the PDF documents (Getting Started, Programming Reference, and Design Guide).
The ISO can be found via the "ZIP" link.
Chapters:
Intro (0:00)
Video Subsystem Discussion & Example (2:55)
Hand Control Subsystem & Example (13:41)
Running Unmodified PC Titles on VIS (21:12)
First Port Attempt: Color Computer 2 Emulator / DOSMON (28:46)
Porting Commander Keen in Keen Dreams (46:36)
Commander Keen Demo (1:15:27)
Outro / What's Next (1:23:16)
I do these videos unscripted, so I apologize if the in-the-moment descriptions of things are a bit scattered. If you have any questions/comments about this video, you can find me in any of these fine locations:
The Tandy Discord Server
The CoCo Nation Discord Server
The TRS-80 Color Computer (CoCo) group on Facebook
The CoCo Crew Podcast group on Facebook
On the Vintage Computer Forums (vcfed.org)
The TRS-80 Models I-4/4P Group on Facebook
Tandy / Radio Shack Model II /12 / 16 / 16B / 6000 Owner's Group on Facebook
X (I'm TJBChris there...)
Mastadon: TJBChris@mastadon.social
The Level29 BBS (I'm TJBChris there, too.)
Particles BBS (Guess who I am here? Yeah, TJBChris.)
Thanks for watching!
