Thomas Jentzsch Posted January 5, 2019 Share Posted January 5, 2019 (edited) Thanks to DirtyHairy, Stella's TIA emulation has greatly improved over the last two years. It is now able to emulate a standard TIA almost completely with perfection. But "TIA is a beast" and on top of that Atari used numerous slightly different TIA versions in their consoles. Some of these TIAs cause problems with original games and homebrews. To help homebrewers avoiding such problems in the future, we want to analyze these TIA differences and then add some developer options to Stella. This website describes a lot TIA chips in detail, together with the potentially affected games.Note: Most INFO links are broken, you have to change the path into "www.ataricompendium.com/game_library/easter_eggs/vcs/" to make them work.So if you own a console with an odd TIA which exhibits one of these problems and maybe also own a flash cart (e.g. Harmony, Krokodile, CC, Supercharger, Uno-Cart), you can help us. For now we are mostly interested into consoles which display stray dots in Ebivision's Pesco/Pac Man (we suppose Atari Video Cube, QuickStep, Thrust and Ixion might be affected on these too) display extra pixels in Masters of the Universe - The Power of He-Man; note that there are two different variations of the problem (here e.g. Obelix, Octopus, Room of Doom, Ski Hunt, Space Treat Deluxe, Squeeze Box and SW-Ewok Adventure might be affected too) have problems with Kool Aid Man and Thunderground (probably Spider Fighter too) have problems with G.I. Joe - Cobra Strike (see pictures attached) There are more bugs listed (especially with the Cosmic Ark stars), these may follow once we unterstand the other ones. If you want to help us, please tell us (here or via PM) which of the bugs listed above your console exhibits if you own a flashcart (for executing test ROMs) or any of the ROMs related to your console glitch listed above We will then ask you to verify other games (as listed above) and try some test programs. With your help we hope to be able to adapt Stella to as many TIA variations as possible. Fingers crossed! Edited January 7, 2019 by Thomas Jentzsch 3 Quote Link to comment Share on other sites More sharing options...
fiddlepaddle Posted January 5, 2019 Share Posted January 5, 2019 Hello, my name is Fiddlepaddle. I am a console owner, and I am odd. 9 Quote Link to comment Share on other sites More sharing options...
+stephena Posted January 5, 2019 Share Posted January 5, 2019 Hmm, should have expected someone to respond like this 1 Quote Link to comment Share on other sites More sharing options...
+Karl G Posted January 5, 2019 Share Posted January 5, 2019 I've found out the hard way via development that my TIA timing on my Jr. is slightly different, and have seen issues with a 48-pixel routine that looked fine on other consoles as a result. I haven't yet tested those other games on this console, but I have a Harmony cart and should have time to give it a try this coming week. Having oddball TIA support in Stella would be awesome. Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted January 6, 2019 Author Share Posted January 6, 2019 I've found out the hard way via development that my TIA timing on my Jr. is slightly different, and have seen issues with a 48-pixel routine that looked fine on other consoles as a result. I haven't yet tested those other games on this console, but I have a Harmony cart and should have time to give it a try this coming week. Having oddball TIA support in Stella would be awesome. Do you still have that 48 pixel routine. Also which of the bugs listed above affect your console? Quote Link to comment Share on other sites More sharing options...
+Karl G Posted January 6, 2019 Share Posted January 6, 2019 Do you still have that 48 pixel routine. Also which of the bugs listed above affect your console? I do; I'll just need to dig it up. I'm not sure which of those bugs affect my console. I should have some time to do some testing with my Harmony cart tomorrow. Quote Link to comment Share on other sites More sharing options...
Jstick Posted January 6, 2019 Share Posted January 6, 2019 (edited) It's not on your list, but I have an NTSC JR that exhibits a small visual issue in Spider Fighter. There was a thread on here regarding others having the same issue, and someone posted a patched PAL rom that fixed the problem (Which I couldn't test on my North American system). Edited January 6, 2019 by Jstick Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted January 7, 2019 Author Share Posted January 7, 2019 (edited) Then you might have a console that has problems with Master of the Universe too. And/or it has problem with Kool Aid Man or Thunderground (see above). Can you test these games for us? In case of any glitches, screenshots are welcome. Edited January 7, 2019 by Thomas Jentzsch Quote Link to comment Share on other sites More sharing options...
DirtyHairy Posted January 7, 2019 Share Posted January 7, 2019 If you have a Jr. with an oddball TIA, please give also this test ROM a spin and post images: modified_test.zip Beware that the pattern might change over the course of a few minutes as the console warms up. Quote Link to comment Share on other sites More sharing options...
Jstick Posted January 7, 2019 Share Posted January 7, 2019 I won't have access to my JR until next week, but I'll test the mentioned games when I have a chance (Although I recall Kool-aid man working fine on that system). Quote Link to comment Share on other sites More sharing options...
+Karl G Posted January 8, 2019 Share Posted January 8, 2019 Do you still have that 48 pixel routine. Also which of the bugs listed above affect your console? Okay, I'm attaching the ROM that contains the 48-pixel routine that glitches on my and my girlfriends Jrs, but works fine in Stella and on other consoles. It was inadvertently doing an early HMOVE at cycle 71 instead of 73 (as discovered by SpiceWare). I've also tried out the other games. He Man and Pesco look normal, but Kool-Aid Man and Thunderground have issues. The "oddhmovetest" definitely looks a lot different than it does on Stella. Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted January 8, 2019 Author Share Posted January 8, 2019 Many thanks for the pictures. Looks like your console is only affected by "early HMOVE" problems. BTW: The ROM is missing. Quote Link to comment Share on other sites More sharing options...
+Karl G Posted January 8, 2019 Share Posted January 8, 2019 I also forgot about GI Joe, which also worked fine on my system (or at least, it's no worse on my system than it is on others!). ScoreDisplay2.bin Quote Link to comment Share on other sites More sharing options...
26gc Posted January 8, 2019 Share Posted January 8, 2019 I'm odd too.. and I even smell funny. Happy to be your friend, Andre 1 Quote Link to comment Share on other sites More sharing options...
DirtyHairy Posted January 8, 2019 Share Posted January 8, 2019 The "oddhmovetest" definitely looks a lot different than it does on Stella. Thanks for testing! As a reference, here is what this ROM looks like in the current code (with an experimental option to emulate what I think is part of the oddities of this TIA revision). We don't have a 100% match, but the result is very close: 1 Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted January 9, 2019 Author Share Posted January 9, 2019 Just two people who can help us here? Are the oddball TIAs really that rare? Quote Link to comment Share on other sites More sharing options...
Mr SQL Posted January 10, 2019 Share Posted January 10, 2019 Kool-Aid man is the litmus test for odd TIA's I have a Junior but it's TIA is fine, well almost. My Vader has better sound; from discussion with Crispy (he knows the most about it, not the Stella devs) the difference is clearly audible. Juniors with a really odd TIA can't play Kool-Aid man. Another Atari console with an odd TIA is the Flashback portable and Flashback9 Composite version that run AtGames emulator; we were able to patch most of the games to run and didn't have to dump the superchip RAM to figure out how it worked, but we did have to figure it out. Next odd TIA's would be the one in the Reton77 but the Stella devs patched it to run Kool-Aid man (good job). Flashback9 HDMI - this has an odd TIA and an odd vCPU. Answers may vary but those are the consoles that are most challenging to work with; I support them all with games and development tools. Suggestion: Instead of creating your own idea of how an Atari should work and having it only work that one way, make the emu more compatible with existing consoles. You didn't want to support the AtGames emu; looks to me like now you have to support older versions of Stella just like I do if you actually want to support all Atari consoles. Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted January 14, 2019 Author Share Posted January 14, 2019 Anyone with a Jr which has problems with Cosmic Ark around who could do some tests for us? Quote Link to comment Share on other sites More sharing options...
alex_79 Posted January 20, 2019 Share Posted January 20, 2019 (edited) Late 2600 Jr PAL (1991 copyright on the box): (I used NTSC roms for these screenshots, and my TV shows PAL color loss with odd number of scanlines) Pesco Masters of the universe Kool-Aid man (took a while to understand that I have to set the left diff to B to make it run...) Thunderground Spider Fighter G.I. Joe Cosmic Ark Hmove test --------------------------------------------------------------------------------------------------------------------------------------------------------------------------- PAL 7800 this one gave some trouble with bus stuffing and needs a couple minutes of warmup to stabilize its behaviour. I posted a video of the hmove test on the Stella github pages (https://github.com/stella-emu/stella/issues/246): Pesco masters of the universe Kool-Aid man Thunderground this game needs a while to stabilize on this console. here are a few pictures taken while it was warming up: Spider Fighter G.I. Joe Cosmic Ark I have a few other consoles (including a working Tournament table arcade board), but it might take a while before I can test them (they're on storage and a few need some repair work). Edited January 20, 2019 by alex_79 2 Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted January 20, 2019 Author Share Posted January 20, 2019 Thanks a lot for the valuable feedback. It looks like your Jr and 7800 are both having problems with (too) early HMOVEs. And your Jr shows duplicate dots in Cosmic Ark. Thanks for confirming Spider Fighter too. Since Thunderground stabilizes after a while, I suppose the same is true for Kool-Aid Man and Spider Fighter? Quote Link to comment Share on other sites More sharing options...
alex_79 Posted January 20, 2019 Share Posted January 20, 2019 (edited) I tried again and you're right: if I leave the console cool down for a while before testing those two games, I get the same kind of behavior. Edited January 20, 2019 by alex_79 Quote Link to comment Share on other sites More sharing options...
Lynxpro Posted January 21, 2019 Share Posted January 21, 2019 Hmmm.... my Lite Sixer from Christmas 1980 couldn't run any copy of Air Sea Battle. Does that count? Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted January 21, 2019 Author Share Posted January 21, 2019 Hmmm.... my Lite Sixer from Christmas 1980 couldn't run any copy of Air Sea Battle. Does that count? I suppose that was not TIA related. Quote Link to comment Share on other sites More sharing options...
+save2600 Posted January 21, 2019 Share Posted January 21, 2019 Okay, I just went through all my Atari consoles and could have sworn I had one with an "odd TIA"... but turns out, it may be a little more odd than I thought. lol I threw all the typical suspects at it (game wise like He-Man, Kool-Aid Man, Thunderground, GI Joe, etc.) and it displays all of them properly. BUT, here's where it gets interesting... on certain games where there is supposed to be a single solid line, it displays dots instead. And the Harmony menu looks like crap as well. Attached are a few pics: ...and no amount of warmup time corrects this. Is this a funky TIA issue or do I have a component that's going bad you think? System is an unmodified 4-switch woody. RF out. 2 Quote Link to comment Share on other sites More sharing options...
R.Cade Posted January 21, 2019 Share Posted January 21, 2019 Okay, I just went through all my Atari consoles and could have sworn I had one with an "odd TIA"... but turns out, it may be a little more odd than I thought. lol I threw all the typical suspects at it (game wise like He-Man, Kool-Aid Man, Thunderground, GI Joe, etc.) and it displays all of them properly. BUT, here's where it gets interesting... on certain games where there is supposed to be a single solid line, it displays dots instead. And the Harmony menu looks like crap as well. Attached are a few pics: IMGP8439.jpg IMGP8440.jpg IMGP8442.jpg ...and no amount of warmup time corrects this. Is this a funky TIA issue or do I have a component that's going bad you think? System is an unmodified 4-switch woody. RF out. I've seen this on some composite mods with certain televisions. Is this a composite modded unit? Quote Link to comment Share on other sites More sharing options...
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