Tempest Posted January 14, 2004 Author Share Posted January 14, 2004 Ok so I'm not crazy. Great. Unfortunatley this absolutely sucks! Ok everyone try one more thing for me. Try loading up The Last Starfighter and see if the landing pad goes from a light gray to a dark gray immediately at start up. If so, then it's not my wiring, it's the chip! Tempest Quote Link to comment Share on other sites More sharing options...
Charlie_ Posted January 14, 2004 Share Posted January 14, 2004 I'll have to try the other game tomorrow, but I can't see how this "sucks". If the only problem is a Lucas logo and a landing pad in Star Fighter, there really isnt much wrong. :wink: We will have to test more games. I'll get the multicart out again tomorrow. Charlie Quote Link to comment Share on other sites More sharing options...
Tempest Posted January 14, 2004 Author Share Posted January 14, 2004 I'll have to try the other game tomorrow, but I can't see how this "sucks". If the only problem is a Lucas logo and a landing pad in Star Fighter, there really isnt much wrong. Well I'll admit that those problems aren't huge, but I think the colors are also off (it's noticable if you compare). I'd appreciate it if everyone could test the mod vs. a regular 5200 and see if the color problem is only on my unit or if it's a problem with mod. Tempest Quote Link to comment Share on other sites More sharing options...
Charlie_ Posted January 14, 2004 Share Posted January 14, 2004 I notice when I play the 5200 with RF on my high resolution TV, you can see that the 5200 is putting out everyother line (or something). With this mod everything looks solid. That may be the reason the Lucas logo looks like that. Also, considering what I said above, drawing every so many lines can cause artifacting, (A method heavily used by the TRS-80 COCO2 to get 4 colors in high res mode) This could be why colors look different as the games were written with the thought they would only be viewed in RF. This doesnt apply to Emulators running on a RGB monitor, they work different. Only a thought........... Charlie Quote Link to comment Share on other sites More sharing options...
Tempest Posted January 14, 2004 Author Share Posted January 14, 2004 Also, considering what I said above, drawing every so many lines can cause artifacting, (A method heavily used by the TRS-80 COCO2 to get 4 colors in high res mode) This could be why colors look different as the games were written with the thought they would only be viewed in RF. Yes but I'm viewing it through a composite connection. Artifacting works with composite (but not with S-Video). I thought the only differance between RF and Composite is that you're seperating the video from the audio (as opposed to seperating out the chroma and the luma). Tempest Quote Link to comment Share on other sites More sharing options...
Bryan Posted January 14, 2004 Share Posted January 14, 2004 My guess is that the GTIA half-shade pin (LUM0) is wired wrong in the upgrade. This would cause what should be the most subtle bit to become the most significant, and it would cause only half brightness to be available in the normal 8-shade modes. Instead of: least LUM0 LUM1 LUM2 LUM3 most It seems like: least LUM1 LUM2 LUM3 LUM0 most -Bry Quote Link to comment Share on other sites More sharing options...
Tempest Posted January 14, 2004 Author Share Posted January 14, 2004 Is that easily fixable or is the chip going ot have to be redesigned? Would this also explain my "darkness" problem? Tempest Quote Link to comment Share on other sites More sharing options...
Bryan Posted January 14, 2004 Share Posted January 14, 2004 Is that easily fixable or is the chip going ot have to be redesigned? Would this also explain my "darkness" problem? Tempest See my edit above. Yes, it might. You would need to bend up the 4 LUM pins, and re-route them (with wire) into different socket contacts to re-order them (or move resistors on the board). Here's what I bet would fix it: Bend up 22, 23, 24 & 31 Route pin 22 into hole 23, 23 into 24, 24 into 31, and 31 into 22 -Bry Quote Link to comment Share on other sites More sharing options...
Tempest Posted January 14, 2004 Author Share Posted January 14, 2004 Got a diagram for that? When you say bend up pins, I assume you mean on the chip plugged into the board (GITA?). That would mean soldering a wire to each pin and then soldering it into the hole where the pin would go right? Tempest Quote Link to comment Share on other sites More sharing options...
Bryan Posted January 14, 2004 Share Posted January 14, 2004 Another question about the Lucasfilm logo, are all the bright bars the same shade, or do they get any darker as they go down? If they're all the same color, then it might be an even worse mistake. In either case, LUM0 is going to the wrong place. Yes, you'd have to bend up pins and solder to them (although I'd stick the other end of the wires into the socket holes for now rather than solder to the socket). -Bry Quote Link to comment Share on other sites More sharing options...
Tempest Posted January 14, 2004 Author Share Posted January 14, 2004 Another question about the Lucasfilm logo, are all the bright bars the same shade, or do they get any darker as they go down? No they get darker as they go down. Look at the first page of this post, the logo is there. Anyone want to try this and see if it works? Also, anyone got a pin number diagram? BTW someone should contact the guy who made this mod and see what he says. I honestly don't remember his name. Tempest Quote Link to comment Share on other sites More sharing options...
Bryan Posted January 14, 2004 Share Posted January 14, 2004 Before you do anything... let me make sure the pins are right. -Bry Quote Link to comment Share on other sites More sharing options...
Bryan Posted January 14, 2004 Share Posted January 14, 2004 Okay... the mistake probably originated with Atari's schematic for the 400/800 which shows LUM3 on pin 31 of CTIA. However, CTIA did not actually support this pin. On the 400/800 motherboard, it's routed correctly into the least significant video buffer. All other 8-bit schematics show the pins properly numbered as in the picture above. It appears this upgrade numbered them based on the incorrect CTIA diagram. This means: LUM0 (GTIA pin 31) needs to go into hole 22. LUM1 (GTIA pin 22) needs to go into hole 23. LUM2 (GTIA pin 23) needs to go into hole 24. LUM3 (GTIA pin 24) needs to go into hole 31. -Bry Quote Link to comment Share on other sites More sharing options...
Charlie_ Posted January 14, 2004 Share Posted January 14, 2004 Somewhere, I got lost. Is this what we should try? Bend up 22, 23, 24 & 31 Route pin 22 into hole 23, 23 into 24, 24 into 31, and 31 into 22 I sent an e-mail to the 8bitdomain where I purchased the mod, and a link to these posts. Charlie Quote Link to comment Share on other sites More sharing options...
Bryan Posted January 14, 2004 Share Posted January 14, 2004 Here's a diagram of the GTIA chip in the Socket on the mod. You should use small wire-wrap type wire to do this. THIS IS UNTESTED. I need someone to verify the results. -Bry Quote Link to comment Share on other sites More sharing options...
Charlie_ Posted January 15, 2004 Share Posted January 15, 2004 I just "modded" the mod as you suggested. It does fix the Lucas logo. However, now the colors are not very rich at all. An example being, Super Pacman, pacman is so pale he is just about white. Suggestions? Charlie Quote Link to comment Share on other sites More sharing options...
Bryan Posted January 15, 2004 Share Posted January 15, 2004 I just "modded" the mod as you suggested. It does fix the Lucas logo. However, now the colors are not very rich at all. An example being, Super Pacman, pacman is so pale he is just about white. Suggestions? Charlie Well, with GTIA, the color saturation is the inverse of brightness. In other words, the brighter a color is, the more washed out it appears. The overly dark colors produced by the mistake caused the colors to look more saturated than they will now. I haven't seen the output, however, to judge if it's 100% correct now or not. It's possible the mod is producing weak colors, as well. Perhaps the chroma level was set based on the mistake in the Luma circuit. I really need to look at one of these things to go much further. For the moment, you could turn your TV's Color adjustment up. -Bry Quote Link to comment Share on other sites More sharing options...
Charlie_ Posted January 15, 2004 Share Posted January 15, 2004 I have already put it back the way it was. I think your right, the mod is set for the mistake. Some games are just fine and other look so dull its unbearable. So there is no one color setting for the TV I found. PLus it would suck to adjust the color of the TV going from xbox or jaguar (puts out strong colors) to the 5200 all the time. All things considered, this mod looks great the way it is right now. I'd still recommend it. I'd also buy another if there was a revision to fix it Charlie Quote Link to comment Share on other sites More sharing options...
Tempest Posted January 15, 2004 Author Share Posted January 15, 2004 Hmm.. But if the colors on the mod were set for the error, wouldn't there be one color adjustment that would fix it? I'm not ready to give up! BTW did you try TLSF? Anyone e-mail the mod maker? I wonder if he'll offer a fix? If not, can anyone else do it? Tempest Quote Link to comment Share on other sites More sharing options...
Bryan Posted January 15, 2004 Share Posted January 15, 2004 Hmm.. But if the colors on the mod were set for the error, wouldn't there be one color adjustment that would fix it? I'm not ready to give up! Well, making any adjustments to the board would require the ability to desolder surface mount components. It would be interesting to compare the color output to an A8 computer. -Bry Quote Link to comment Share on other sites More sharing options...
kenfused Posted January 15, 2004 Share Posted January 15, 2004 You probably could just ground the offending line. It will cost you half of the brightness levels (the odd ones) in that gtia mode but at least it shouldn't look as bad when it is used. Quote Link to comment Share on other sites More sharing options...
Tempest Posted January 15, 2004 Author Share Posted January 15, 2004 You probably could just ground the offending line. It will cost you half of the brightness levels (the odd ones) in that gtia mode but at least it shouldn't look as bad when it is used. No no no... That's not a proper fix and would probably make things worse. Someone needs to take the chip design and "fix" it. Unfortunatley that is FAR beyond my skills. Tempest Quote Link to comment Share on other sites More sharing options...
Charlie_ Posted January 15, 2004 Share Posted January 15, 2004 I'm still happy with the mod, besides for the 2 games we found it doesnt work right with (so far) it looks great. What worrys me is in the future with all these great homebrew games coming out and one of them doesnt look right with this mod installed. I'm jumping on Castle Crisis, I can't wait for it to be released. I'll be bummed if it doesnt work right with this mod Charlie Quote Link to comment Share on other sites More sharing options...
Tempest Posted January 15, 2004 Author Share Posted January 15, 2004 I'm still happy with the mod, besides for the 2 games we found it doesnt work right with (so far) it looks great. Did you try it with TLSF? Did you try it with all the other 5200 games? I'm curious as to how many games this bug affects. Tempest Quote Link to comment Share on other sites More sharing options...
8bitdomain Posted January 16, 2004 Share Posted January 16, 2004 I have reviewed the problem reported in this forum regarding the luminance order error, and it appears that there is an error. The Atari 5200 service manual shows the following: Lum0 pin 31, Lum1 pin 22, Lum2 pin 23, Lum3 pin 24 The good news is that the "fix" does not require any cuts or jumpers, the bad news is that the 4 luminance resistors need to be removed and re-located. I have attached a diagram showing what needs to be moved. I understand that not everyone has the tools to do SMT rework. So I will do the fix for anyone who returns the board to me. I will fix and return to board "no charge" within 72 hours of receipt. I have tried the fix and it does provide more drive in both composite and svideo operation. However it does require some brightness adjustment in your TV. If you are satisified with the quality that you presently have than I would recommend that you keep your board as-is. Regards, Mike support@8bitdomain.com Quote Link to comment Share on other sites More sharing options...
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