SD System 3 Arcade Card Game - Graphic Glitches, Crashes and Resets

s. k. technique said:

I had a quick look but can't see any reports on these.

The games are the neo geo conversions using the Arcade card:

Garou Densetsu 2 - Aratanaru Tatakai
Garou Densetsu Special
Ryuuko no Ken
World Heroes 2

The above titles all have intermittent graphical glitches on sprites and backgrounds, eventually causing the game to crash and hang, or crash and reset.

Strangely, Sapphire and Strider which are both Arcade card games seemingly work without any issues (got to the last level (stage 5) on Strider) as does normal CD games.

I thought it may be poor ROM dumps, but I have tried around three different sets, some as .cue & .iso, others as .cue & .bin(s) and they all have problems.

In terms of testing, I have tried two SD cards (Sandisk & Toshiba) both in exFAT and FAT32, but still the same issue.

I'm using System Card 3.0, with held Start and Select Reset turned OFF.

How are you getting on with these titles?
I am not sure whether these are working fine for everyone else, or the community are not reporting as they don't bother playing these games because they already own the superior originals (although these are pretty decent conversions).

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greatfunky said:

Same issues here under garou densetsu 2 yesterday , i had some sprite glitches and even at a moment a black screen with a reset of the game.
The in-game trigger option is disabled , my console is also the blue CoreGrafx , stock and in near mint condition , using a good 9V 1A stabilized psu .

I need to test more arcade card games ....

Edit : i tested world heroes 2 for more than 30 min without any issues for me , then retested garou densetsu 2 from 2 differents sources (Redump Validated)and still had glitches and freeze with this game ...

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s. k. technique said:

I had a quick look but can't see any reports on these.

The games are the neo geo conversions using the Arcade card:

Garou Densetsu 2 - Aratanaru Tatakai
Garou Densetsu Special
Ryuuko no Ken
World Heroes 2

The above titles all have intermittent graphical glitches on sprites and backgrounds, eventually causing the game to crash and hang, or crash and reset.

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neodev said:

Ok, it seems to boil down to some issues we found while developing the cart, let me explain:

It seems some pce/coregfx models are really noisy inside and the digital signals aren't too "clean" and sometimes have glitches large enough to be picked as a different logic level by the level shifters. Old, slower hardware is more resilent to that noise, but fast modern hardware can pick them unintentionally when sampling the signals. The FPGA program tries to filter and ignore any glitches found, and needs the signals stable in order to accept them (as a read or write) but maybe it still needs more tweaks.
It took a long time to make the code resilent to those issues, but it's something that can be fixed in firmware, now we just need a way to reproduce it, as the current firmware was tested to be glitch free in all our consoles (my 4 coregfx, 4 pce, 1 sgx, 1 tg16 + the ones Alex has) and our testers'.

What I found is that the consoles with more issues were also the ones with more jailbars and rgb noise, so all this seems to be related to something inside the consoles that wears over time (maybe capacitors). That doesn't mean you need to change anything, we'll fix that in firmware, it's just a general comment about the current state of the ageing PCE consoles . I have 4 PCEs, and initial firmwares worked great on one of them, the one I used for development. One day, I switched to other one, and arcade card failed randomly. It is what I call the "cursed PCE", and my main development one ATM . It has strong jailbars, it's yellow decolored and smells of cigarrette smoke. I haven't been brave enough to open it, fearing what I could find inside .

Also, on a side note, having a region mod installed probably adds noise to the data lines because of the longer and unsielded wires of the usual mods will pick more noise.

Why it affects only to Arcade Card? my guess is that there are some random read/write signal glitches that happen sometimes (also I've seen the CPU repeat a read or write for no apparent reason, probably pipelining) but they don't affect the game as there aren't usually any side effects and reading or writting twice the same address in the SSDS3 is mostly harmless (that's not really true, especially with cd registers, but they are very filtered and accessed slowly, but mostly is) but the arcade card, as every read or write to the data port increases the reading address, an erroneously repeated read or write causes a big difference, shifting the data, and causing severe graphic glitches.

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monads said:

I tested these titles out lastnight with this setup:

In-Game Trigger Off
Composite connections
256gb Evo+ card
Core Grafx II (unmodded w/original NEC PSU)

I didn't experience any reported issues after 5-10min of use with the exception of "Garou Densetsu 2 - Aratanaru Tatakai". It crashed during gameplay requiring a reboot power off/on cycle. Perhaps I would've seen issues with the other titles had a played longer than 10min?

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greatfunky said:

Thanks for all these details neodev , i don't own my coregrafx for a very long time (few weeks before my SSDS3) and i was expecting jailbars like my duo-r and ready to fix it .

But honestly i couldn't find one : the picture is perfect via SSDS3 output, even with my low cost RGB cable.

Anyway , i'm very confident , you'll hunt down these issues and fix it, as ever ....


Very interesting , i just finished Garou Densetsu Special and Ryuuko no Ken without any glitches , so my issue seems to be only with Garou Densetsu 2 , just like you ....

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s. k. technique said:

Thanks neodev for taking the time to give a detailed explanation. Good luck with the fix, is there any further testing I can do to help?

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