Welcome to the VirtualVCS (Atari 2600) emulator for the Atari Jaguar
Over time TSD handed the VirtualVCS source code to Carl Forhan who assemebled, with considerable work, the VirtualVCS demo that has floated around the internet for years. With the release by Curt Vendel, Atari Historian, of the other Atari 2600 emulator, it has been the hope of Carl, Curt, and many others (including myself) to one day see working Atari 2600 games on the Atari Jaguar.
As later explained in this message under "Background information" game images have been hex edited in to replace the game images already in the VirtualVCS demo. The menu graphics format in VirtualVCS were unraveled by sh3-rg.
The main objective is to find games that work in the confines of the abilities of VirtualVCS in it's alpha state. The strengths of this emulator being very close to true speed emulation, good controls, and many display abilities intact. The weaknesses being no sound, no hit detection, some display abilities needing refinement and no apparent bank switching ability using rom images of 4K or less. Limiting, but not impossible.
All efforts are for the enjoyment of the Jaguar community, and in the hopes to understanding the true technical limitations to add in better development of VirtualVCS and/or the 2600 emulator later down the road. Images can be loaded on rom loaders (Skunkboard, Flash card (though not tested)) to try out. No actual cartridges will be sold from this, strictly fun and research.
The following games have been found to work (more than less) under these conditions:
Mario Brother 4K fan game released March 23, 2018: Download
More multicarts are planned. Instructions have been provided for others to experiment with VirtualVCS to find other games that work as well.
A Google Spreadsheet has been started to record the testing of Atari 2600 titles that could work in VirtualVCS. If you would like to participate in research, send me a PM.
---Background information on the Hex Editing ---
---Posted Fri Mar 23, 2018 6:31 AM --------------------------------------------------
So this whole idea started with hacking my Bubsy hack into VirtualVCS, and it displayed pretty well.
Then I started to wonder, what if I could find a game that could work in the limited range of games that would actually work on VirtualVCS and hack those in with a hex editor.
So far I have found that 2K and 4K images work. So far no luck with anything greater.
A sweep for "STA CXCLR" (85 2c) and those that use that method of hit detection also helped.
And after playing around, I found a game that displayed fairly well, and actually interacted in the environment at least somewhat. A 4K version of Mario Brothers. The turtles won't kill you, but you can hit from underneath and knock them over, and then afterwards go up and knock them over. Actually playing the original Mario Brothers game, it has it where the Turtles do no kill you, and all the hit detection I mentioned above.
Mario bros_4k_v2.bin 4KB 53 downloads
All that is not working then on the Virtual VCS in this case is the score.
So here we have a working VCS game on the Jaguar under VirtualVCS. Just select option 2 (where Pac-Man was, on the menu)
vvcs-Mario brothers.rom 1016KB 63 downloads
A fun find. Plans are try other images, see what games don't have the limitations of the VirtualVCS, and find other games that more than less work. Such games as Video Checkers and chess, hangman, and others have been suggested. Asteroids was suggested as it did not use the 85 2c style of hit detection. If we could get a 8K game to work on VirtualVCS.
And for that, maybe some of the Super Charger hacks will come in handy?
More to come. Or perhaps if you want to try hex hacking, here is the copy of Virtual VCS that I found...
vvcs.rom 1016KB 51 downloads
50 VirtualVCS roms with 300 Atari 2600 roms to try. (April 4, 2018)
Adult Pack 01-Women (April 17, 2018)
Adult 01-Women.zip 970.28KB 52 downloads
Adult Pack 02- Men (April 17, 2018)
Adult 02-Men.zip 1013.51KB 52 downloads
Puzzle Pack 01 (April 18, 2018)
Puzzle 01.zip 675.25KB 47 downloads
Edited by doctorclu, Wed Apr 18, 2018 12:17 PM.