George35 Posted January 5, 2011 Share Posted January 5, 2011 Anyone have any trouble running Skeleton+ on the Harmony? All I get is a black screen, but I do hear sound effects. Quote Link to comment Share on other sites More sharing options...
+batari Posted January 5, 2011 Share Posted January 5, 2011 I examined the Skeleton+ game code and I found a programming error, so Harmony is not the problem. The game code produces an improper vertical sync signal, which is needed for a proper video display. This also explains why the sound works but you see no video. If you want to play this game, I suggest using a different television, as yours seems to require a proper vertical sync signal while other televisions may not. Quote Link to comment Share on other sites More sharing options...
DEBRO Posted January 5, 2011 Share Posted January 5, 2011 Hi there, I examined the Skeleton+ game code and I found a programming error, so Harmony is not the problem. The game code produces an improper vertical sync signal, which is needed for a proper video display. This also explains why the sound works but you see no video. If you want to play this game, I suggest using a different television, as yours seems to require a proper vertical sync signal while other televisions may not. Where can I find the Skeleton+ source? Was it released publicly? I looked at the Skeleton code and the VSYNC routine looks to be fine. Did it change in Skeleton+? Quote Link to comment Share on other sites More sharing options...
+batari Posted January 5, 2011 Share Posted January 5, 2011 (edited) Hi there, I examined the Skeleton+ game code and I found a programming error, so Harmony is not the problem. The game code produces an improper vertical sync signal, which is needed for a proper video display. This also explains why the sound works but you see no video. If you want to play this game, I suggest using a different television, as yours seems to require a proper vertical sync signal while other televisions may not. Where can I find the Skeleton+ source? Was it released publicly? I looked at the Skeleton code and the VSYNC routine looks to be fine. Did it change in Skeleton+? I did not find any source, I simply fired Skeleton+ up in Stella and found that the beginning VSYNC pulse occurred at cycle 20 in scanline 259 and the ending pulse occurred at cycle 9 of scanline 262. Ideally, the pulses should occur right after a WSYNC - i.e. cycle 3, but even though there seems to be a little leeway here, cycle 20 is way too late. Edited January 5, 2011 by batari Quote Link to comment Share on other sites More sharing options...
DEBRO Posted January 6, 2011 Share Posted January 6, 2011 Hi there, I did not find any source, I simply fired Skeleton+ up in Stella and found that the beginning VSYNC pulse occurred at cycle 20 in scanline 259 and the ending pulse occurred at cycle 9 of scanline 262. Ideally, the pulses should occur right after a WSYNC - i.e. cycle 3, but even though there seems to be a little leeway here, cycle 20 is way too late. Ahhh...I was just looking for the three scan lines. I totally missed the cycles when VSYNC is invoked. Quote Link to comment Share on other sites More sharing options...
EricBall Posted January 27, 2011 Share Posted January 27, 2011 Huh, this is the first time I've heard of this problem. (Or is it... hmm, vague memories of a complaint.) There was a bug in the original release of Skeleton+ (and maybe in the Activision compilation) where the YOU WIN screen would roll because I messed up the scanline counter. This was corrected in later carts. I don't think the source for Skeleton+ was ever released. The source for Skeleton (possibly an early version) might be in the Stellalist archives. However, I might be able to track down the source code and make a patch. I just happen to be transferring my backups to a new 2TB external drive. Quote Link to comment Share on other sites More sharing options...
DT Kofoed Posted June 28, 2011 Share Posted June 28, 2011 However, I might be able to track down the source code and make a patch. I just happen to be transferring my backups to a new 2TB external drive. Any word on the patch? I love the game, but it won't play on my HDTV through the Harmony cart, and I'm hesitant to purchase the cart of Skeleton+ itself if the error is causing havoc with my tv rather than the harmony... Quote Link to comment Share on other sites More sharing options...
+thegoldenband Posted January 1, 2012 Share Posted January 1, 2012 I had this exact same problem when playing on my little brother's TV, which is very sensitive to scanline problems and screen rolls -- it was rolling on Gunfight, and maybe even one or two mainline commercial releases (can't remember which). We were using my Harmony cart and his Atari Jr.; I don't remember the make of the TV. A fix would be great, especially if I eventually get him an AV-modded console so that he can enjoy the stereo effects (he's planning to get a Harmony cart). Quote Link to comment Share on other sites More sharing options...
Lucky Man Posted June 27, 2013 Share Posted June 27, 2013 Bumpity-bump! I finally got my Harmony Cart set up last week and also noticed this problem with Skeleton+. The strange thing is... I own a Skeleton+ cartridge and it plays perfectly on my system and also using the Cuttle Cart. Why is there only a problem when playing it on the Harmony? Quote Link to comment Share on other sites More sharing options...
+Mitch Posted June 27, 2013 Share Posted June 27, 2013 Maybe we need to dump the ROM off of your cart. Could be it is the bug fixed version. Mitch Quote Link to comment Share on other sites More sharing options...
Lucky Man Posted June 28, 2013 Share Posted June 28, 2013 Maybe we need to dump the ROM off of your cart. Could be it is the bug fixed version. Mitch I don't think there's a difference. I used the same rom from AtariAge with the Cuttle Cart and it plays perfectly as well. Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted June 28, 2013 Share Posted June 28, 2013 Wasn't there a bug in Skeleton+ where the code relied on some RAM to be zero initially? Quote Link to comment Share on other sites More sharing options...
olivil Posted August 8, 2013 Share Posted August 8, 2013 (edited) Would like to have a final answer on this. Or, ideally, a patch or fixed rom! Edited August 8, 2013 by olivil Quote Link to comment Share on other sites More sharing options...
+batari Posted August 21, 2013 Share Posted August 21, 2013 I recall the programming error to be the classic zero page load where an immediate load was intended. Some hardware exploits these bugs while some does not. I will look later and see if a patch is possible. Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted August 21, 2013 Share Posted August 21, 2013 (edited) Maybe this is the problem START: SEI ;2 CLD ;2 LDA #$00 ;2 LDX #$44 ;2 L1618: STA VSYNC,X ;4 INX ;2 BNE L1618 ;2 No idea why the first 44 bytes (TIA!) are not initialized. Try the attached version. Maybe it helps. Not sure. SkelPlus_Fix.zip Edited August 21, 2013 by Thomas Jentzsch Quote Link to comment Share on other sites More sharing options...
Lucky Man Posted August 22, 2013 Share Posted August 22, 2013 That did it! Works great now. Thomas, you're the best! Quote Link to comment Share on other sites More sharing options...
BrianC Posted August 22, 2013 Share Posted August 22, 2013 Sweet. I'll give it a try on my harmony cart! Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted August 22, 2013 Share Posted August 22, 2013 That did it! Works great now. Wow! That was just a very vague guess. Lucky me! Quote Link to comment Share on other sites More sharing options...
+batari Posted August 25, 2013 Share Posted August 25, 2013 Interesting. Most of the TIA is initialized due to the mirror at $40-$6C so it's really just four registers causing all the trouble. I'm guessing something with VBLANK. I'm pretty sure that Harmony has VBLANK off when starting a game so Skeleton+ must not be turning it on (which is odd as all games should toggle VBLANK every frame.) Maybe this game does not use VBLANK at all? That would explain rolling issues others reported and indicates another possible bug in the game. Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted August 25, 2013 Share Posted August 25, 2013 Maybe this game does not use VBLANK at all? After a brief test I think you are right. Most TVs can accept black instead of VBLANK, but some don't. Maybe depending on the brightness settings? I had a similar problem in Splatform 2600, where TVs started to roll when the screen was flashing. Quote Link to comment Share on other sites More sharing options...
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