SD2SNES/FXPAK Pro loses sync

[oli_lambda]

Hi there,

I very recently bought a FXPAK/SD2SNES Pro from everdrive.me to use on my SFC. Sadly, every games I tried to play make the TV and the SFC lose sync at some point.
The issue is rather random but seem to happen quicker/more often with games that uses special chips (could play SMW for 10' maybe before crash). Some issue seems to be reproducible as well, like opening a help dialog in Yoshi's Island that make the system lose sync temporarily. The game often come back after a few seconds, sometimes not (or I just tired waiting). Funnier, with a tool like 240p test suite, it happens that sync is lost when changing menu, and come back if going forward/back in menus.
About the hardware, it is a release SFC (everything on version 1 in SD2SNES menu), I'm using an after market power supply because I am in Europe and I can't use original power supply on SFC. It's rated for 10V 1A DC so it should be good afaik. The cable is the universal Nintendo RGB cable from Retro Gaming Cables. The issue also happens with the original PAL RGB cable and original N64 PAL composite cable. Searching on the topic, I saw that this issue happens quite often, saw it here in some topics (http://krikzz.com/forum/index.php?topic=9512.msg71979#msg71979, http://krikzz.com/forum/index.php?topic=8952.msg70326#msg70326) or elsewhere (https://atariage.com/forums/topic/287892-sd2snes-pro/page/3/). What is a little troubling me is that it happens with power modded SNES (mine is not), pointing to something else than faulty systems... Note that I didn't see the issue on my PAL SNES during a very short test. Anyway, all tests are passing in the diagnostic firmware.

Is there a solution to this ? Could it be an issue that could be resolved on the software level ?
If not, I guess I'll just get a refund but that would make me a little sad given how hard it can be to find NTSC versions of games here in Europe.

[ikari_01]

Hi!

Please see http://krikzz.com/forum/index.php?topic=9512.msg73754#msg73754 for a brief analysis. Right now I'm trying to get my head wrapped around it.
Since you mention living in Europe, would there be any chance that you would be willing to lend me your console (shipping cost covered by me) so I can investigate the issue further?
I have around a dozen SNES/SFCs including old models but none show the issue

[oli_lambda]

Hi ! Thanks for your answer, I kinda gave up hope and was looking for another SFC with higher chip revision. Even posted just before on console repair reddit to see if this couldn't be an hardware issue.

Anyway, I'd be glad to help. About sending the SFC, I'll consider it but with no surprise and as half of Europe, I'm locked down so it will have to wait. We could discuss that privately.

But for now I can try things myself. For the pins to tape, did you mean these two on both sides (see the attached picture)?
Also note that I'm software engineer. Well my skills are miles away from system or chip programming but maybe I could learn. I'd love to contribute to the project if possible but there isn't many onboarding details on github or elsewhere that I could find. So if you care to explain how to get on it and if a computer is the only needed tool, I could even debug that myself or give you debugging details remotely. Let me know!

[oli_lambda]

Okay so listening to the video linked in the other thread, I taped the leftmost pin on both sides (picture attached for those interested) and... it works ! No more glitch in Yoshi's Island and I've been able to see the full FFVI introduction which wasn't possible before. I'll do more testing but I guess this little tape will stay in place for now. I read on twitter that this pin only serve to time the MSU1 chip feature which I'm not so much interested for now. Thanks for the tip !
I'd still be glad to help further on if I can.

[ikari_01]

Thanks for testing! If you are willing to open your SFC could you tell me its PCB model number (something like SHVC-CPU-01)? It's probably printed on the PCB beneath the front metal shielding.

[oli_lambda]

It is a SHVC-CPU-01. PCB picture joined if useful.
I played a little bit and it definitely fixed the syncing issue, but while playing A Link to the Past, after I'd say ~1/2h, the brightness started to flicker and the SFC rebooted. Hardware issue or could it also be coming from the cartridge as well in your opinion ?

[ikari_01]

Cool, thanks! Could you do a closeup of the bottom of the PCB, of the area I marked in the photo?

Regarding the other glitch it may need attention but it could just have been a general contact issue. If you like try wiggling the cartridge back and forth a bit during operation and see if it crashes easily.

[oli_lambda]

Picture attached, will that do ?

For the other issue, thanks for the tip, I'll see. If I cannot sort it out, I'll look for help. ^^

[oli_lambda]

Hello !

I could test a little more and the issue I talked about is very frequent. The brightness flickers quickly and then, the system resets. It happens randomly, a little like the sync issue I had earlier.
It tried to wiggle the cartridge and it doesn't seem to change anything... Hard to tell I must say as the issue is quite sudden : it's possible to have several minutes without issue and then it flickers for 2s and resets instantly. Sometimes it fails on sd2snes menu already.
I wonder if this could be linked to the cartridge as well?

By the way, could you find out what the original issue was?

Thanks !