Debug for NeoCD

SNKorSWM

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So the region/dips/softdips settings are saved separately per game a la options in the Metal Slug series, or does it contain settings from multiple games?
 

smkdan

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So the region/dips/softdips settings are saved separately per game a la options in the Metal Slug series, or does it contain settings from multiple games?

Every game gets one separate save for itself. You can make a configuration for Pulstar and it will only be recognized/loaded when playing Pulstar. If it doesn't find a save file it just loads the NGCD default.

@NTM: it's no rush, by then I'll have some attempt at cutting a bit off the load times which will be minimal (if it even works) but still worth a try.
 

Razoola

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Going back to those empty RAM sockets. Just how much space do you think can fit there? It came to my mind today about why the empty RAM sockets are there. I came to the conclusion that SNK planned to use it like a cache. IE when you first load the game the Bios would load all the files from the CD and store it to this RAM. Then instead of the Bios loading data from the CD it would simply copy it from the cache.

If that RAM can be hooked up then it should be very easy to change the Bios to preload and use it without the need of making a new game CD.
 

NeoTurfMasta

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Going back to those empty RAM sockets. Just how much space do you think can fit there? It came to my mind today about why the empty RAM sockets are there. I came to the conclusion that SNK planned to use it like a cache. IE when you first load the game the Bios would load all the files from the CD and store it to this RAM. Then instead of the Bios loading data from the CD it would simply copy it from the cache.

If that RAM can be hooked up then it should be very easy to change the Bios to preload and use it without the need of making a new game CD.

Should be another 48megs. The CDZ is the only system that has these empty slots. The CDZ I fully populated is still running great, no errors or anything. Not that it is using them, but at first I had some pins un-soldered I had some video glitches.
 

Xian Xi

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Can you test it with a logic prob to see if the chips are active?
 

smkdan

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It's a bit over 100mbits now, it would make it easy to shift all load times for a <100mbit game to the initial load like that Razoola. For preloading for larger games it is very situational because say, a shooting game is always loading new GFX/stage layout/pat files etc. KOF could benefit a lot from 48mbit cache, If you assumed 16mbit (obviously less than that) for 1 fighter GFX then you can preload a whole team for KOF. If each fighter were to take 1.5MB space, that could mean no loading between fighter switching. 2 fighters are on the screen, and 4 fighters can be cached and ready to load instantly (PCM probably won't fit, but it's a short load).

I figured they just attached it to PCM/GFX RAM. It can still be used for the same purpose in the end, like copying cached GFX data from latter 32mbit to the first 32mbit where the original game actually used it to display. It can be directly accessed by 68k no matter where it is. I'll put off the CD load time idea and try to access new banks of data.
 
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Clessy

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Just a question. Im not sure if it was mentioned or not but, would a MVS mode be able to be selected on cd games with said bios?
 

Clessy

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As opposed to AES mode a la UNIBIOS?
Why would you want AES mode on a CD game? CD is already a more home feeling that AES. Im saying MVS so you can play it with credits and coins. Does the CD even have the mvs data? If you switched it to MVS mode would it use the cd audio still or chip tunes?
 

smkdan

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It has an MVS mode where it is recognized as MVS and forces 99 credits. I don't know if it will ruin any games, the ones I tried were fine.

@Brian: here's the CDZ test ROM for extra memory. It also has MVS mode/saving I mentioned but the memory test is what I'd like to hear about.

Hit D to get to the memory tester. Only sprite testing works since if there is bankswitching for PCM I don't know where it is, the BIOS never used it and the original system never needed it so I don't have any clues there. Hit button A to test, it should say how many MB it finds or if it failed completely. This is actually unemulated so I am just guessing here, I'll see if there's anything stupid I missed.
 

NeoTurfMasta

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SPR: reboots system
PCM: "pcm test failed"

EDIT 2: Tried the MVS setting and it will reboot the system after selecting it. Tried on KOF99 and Slug2. And there seems to be a problem with Slug2 keeping the debug screen up when Start+Select. It will flash over and over.
 
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smkdan

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Great, if for whatever reason it doesn't work I should have it fixed tomorrow. Also I was wrong about the PCM, forgot it was 8bit. I'll get a test for that later..
 

NeoTurfMasta

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OK, just re-tested slug2 with the MVS added. If I make it MVS at the main menu it reboots, guess thats a duh. When I start playing, I can switch to MVS and it will immediately change my credits to 99 and I loose pause ability. So I assume its in MVS mode then. The St+Select menu will appear, but I have to keep St+Sel held. Since the MVS option is at the top of the menu, I can switch it while holding St+Select.

EDIT:

@smkdan
http://www.neo-geo.com/forums/showthread.php?t=174349 This thread has some pics of the CDZ motherboard. Since I keep forgetting to take pics of mine.
 
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smkdan

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NeoTurfMasta said:
EDIT 2: Tried the MVS setting and it will reboot the system after selecting it. Tried on KOF99 and Slug2. And there seems to be a problem with Slug2 keeping the debug screen up when Start+Select. It will flash over and over.

If it resets when booting, but not when you set MVS in game then I'm 99% sure what the problem is and it should be fixable. If it is what I think it is, it should not reset when choosing MVS at initial load on titles before 1994 or so.

There's also the quirks with MVS mode accessing backup RAM that doesn't exist to set its own soft dips etc., but it can be patched out with each game. Will leave that for later, that just involves downloading every ISO and getting the patch info setup. Easy,just time consuming.

The St+Select menu will appear, but I have to keep St+Sel held. Since the MVS option is at the top of the menu, I can switch it while holding St+Select.

So when the start button is released it goes back in the game? didn't expect that, here's a supposed quick fix. It removes start from the menu so it shouldn't happen again and replaces it with menu item, will fix it later just don't want to mess around with proxy tests for something like that.

SPR/PCM test issues will wait until that's all sorted. If it keeps resetting with whatever I try, I'll put it off until I own one personally since it's very annoying trying to document unknown hardware with proxy tests. It's not practical.

About that flashing, is that where it takes you straight back into the game unless you hold start/select down? Or was it the actual menu screen having glitches? Was the text perfectly readable when in the menu?

Cool pics, looks they left more than just the DRAMs unpopulated. Too bad it's blurry, can't make out any text on it.
 
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NeoTurfMasta

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If it resets when booting, but not when you set MVS in game then I'm 99% sure what the problem is and it should be fixable. If it is what I think it is, it should not reset when choosing MVS at initial load on titles before 1994 or so.

Gotcha, I'm planning on testing some single load games.

So when the start button is released it goes back in the game? didn't expect that, here's a supposed quick fix.

Thats exactly what happens, I'll give the update a shot tomorrow. The flashing was just from holding start select. I did notice some menu glitches on I think SSRPG, but I dont remember which game it was.

@everyone
I have a proto run of 5 boards for a minimal solder bios installation. This will work on both CDZ and Top Loaders. I also made it compatible with the MV-1B and 1C. I'll make another thread with preorders for a full run once I get the protos in and tested.

@smkdan
I'll send you one of the test boards for you to try. I should get them in sometime next week.
 

SNKorSWM

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@everyone
I have a proto run of 5 boards for a minimal solder bios installation. This will work on both CDZ and Top Loaders. I also made it compatible with the MV-1B and 1C. I'll make another thread with preorders for a full run once I get the protos in and tested.

Preorder for modded system, or just the bios chip, or both? It seems that the fix is more complicated than just a socketed bios switch.
 

smkdan

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Just found two lines in the source that would have caused the flashing issue, simulating it caused rapid flash between menu and a light blue screen. The one in previous post wouldn't have done much. Here is a newer ROM pair for that. fixflashstart.bin is the one to try first, it should be like the ROM that previously failed but no flashing and start+select problems hopefully. Also took out a few things that could cause issues with SPR TEST, give that another shot and see if it resets or if it actually says something. Still nothing for PCM test (yet). If SPR test still resets, I'll pretty much need my own CDZ to investigate...

I'd be happy to accept one of the boards if I had an actual system to try on. Can't seem to find a decent deal on a Z, the ebay ones in Japan are all boxed ($$$) and cost like $250-$300 before shipping is even involved, christ. I need a fully loaded Z to get the most out of this, lots to investigate but with poor emulation I can only do so much. I can get the features like MVS mode,dip settings,cheats etc. but taking advantage of fast CDROM access/new RAM calls for an actual system.
 

NeoTurfMasta

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Preorder for modded system, or just the bios chip, or both? It seems that the fix is more complicated than just a socketed bios switch.

Preorder just for the bios adapter. The CD side of the adapter requires one solder point to enable the bios, the MVS (so far) is requiring 2.

fixflashstart.bin is the one to try first, it should be like the ROM that previously failed but no flashing and start+select problems hopefully. Also took out a few things that could cause issues with SPR TEST, give that another shot and see if it resets or if it actually says something. Still nothing for PCM test (yet). If SPR test still resets, I'll pretty much need my own CDZ to investigate...

Busted out SBB2020 and its working great. No more flashing and below are the memory test results.
memory.jpg
 

smkdan

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I thought the ingame menu would be a lot more hassle than that, great to hear.

Don't mind the mangled digits,that's a bug in the display code. The test itself actually did its job. Each line of text with "MB" at the end just indicates a MByte of SPR RAM it successfully found. So it found 4Mbytes and that's all it could see, the extra DRAM isn't showing up for sprites so it can't be used for that. Doubting it is tied to PCM then, Razoola's cache idea sounds the most probably assuming the DRAM actually is usable. What chip can you see the DRAMs going into? There is GRF/MGA etc. chips but where do the extra ones lead? It might help figuring this out.

More tests will come later ofcourse..
 

NeoTurfMasta

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I thought the ingame menu would be a lot more hassle than that, great to hear.

Don't mind the mangled digits,that's a bug in the display code. The test itself actually did its job. Each line of text with "MB" at the end just indicates a MByte of SPR RAM it successfully found. So it found 4Mbytes and that's all it could see, the extra DRAM isn't showing up for sprites so it can't be used for that. Doubting it is tied to PCM then, Razoola's cache idea sounds the most probably assuming the DRAM actually is usable. What chip can you see the DRAMs going into? There is GRF/MGA etc. chips but where do the extra ones lead? It might help figuring this out.

More tests will come later ofcourse..

Damnit, I just put my CDZ back together so the CD drive can sit properly. I do remember them going to a chip that's on the board, so they don't seem to be going to any of the empty sockets. And that guys pics of his board are way too blurry. I'll trace them out today.

Edit: 4 of them definitely go to MGA, having issues tracing the remaining 8. But I'll get it worked out.

Edit2: I THINK that they are going to a chip labeled NEO-OFC.
 
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smkdan

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I think if I read the board layout right, the stock configuration is:

MGA<->16mbit DRAM for 68k
YSA/VOC<->8mbit DRAM for YM2610
OFC<->32mbit DRAM for sprites + 1mbit PSRAM for FIX layer

If I had to guess, 32mbit is attached to sprites (8 DRAMs is the necessary amount for expansion) and 16mbit for the 68k (4 DRAMs are the right number again). I have not seen banking anywhere for the 68k.16mbit is max without banking. And the sprite chip can't access more than 4MB apparently.

It's starting to sound like the DRAM sockets are for easy replacements of faulty DRAM or to allow for either type of DRAM to be used in production. Kind of like the "EPx" sockets on MVS boards that I think just replace the function of existing ROMs without requiring desoldering. You said that you had GFX glitches when the new DRAMs were not properly soldered? That implies the OFC is trying to use the new DRAM in place of the old ones. Just conjecture though.
 
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smkdan

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a pretty boring update, but features that should be in any BIOS of this sort.

mvprg.PNG
ms2illegal.PNG
MVz80.PNG


View all the RAM at any time and exceptions are caught now. It should be like the unibios here, printing out info that helps track down the fault in your system rather than a random reset that tells you nothing. CD system is less vulnerable to corruption because you normally get disc I/O error if it fails to read properly but there's plenty of other cases this can happen with. A few more things to go until the 'core features' are done.
 
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