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everten

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I picked up a damaged CPS2 multi with graphics issues and I'm slowly working my way around the board looking for damage. U34 and U40 were in rough shape and the board has gobs of flux all over the place which makes it difficult to tell where repairs were attempted prior to me. I was going back and forth with @Darksoft in PM, but I think it's better to start a thread. He initially suggested the issue may be the level shifters , but after failing on one of the verification rom sets he said it is likely one of the flashes.

What I've done:
Fixed traces on U40 and U34
Replaced U34, U36, U35, U37

Ran verification rom sets:
'10101010' rom flashes, but gets stuck on 'Verifying' with the ARM processor LED endlessly flashing twice
'01010101' rom flashes, verifies, displays "All done. Have fun" and then displays "Now playing 01010101".I never saw 'OK' or 'ERROR' on LCD.

I'm not seeing any trace damage other than what has already been repaired.

Graphics issues:
50045469198_c3fd777cb7_n.jpg
50046034771_137a296813_n.jpg
 
This looks like an issue where A and B board are not sandwich tied.
You can try to decase the B board and attach that to A board to see the issue can be resolved
 
It could be a faulty flash or the ARM. Try modifying the VERIFY romset to test only one flash. If it gives you OK, then you know the ARM is most probably good and you can narrow down the faulty flash.
 
It could be a faulty flash or the ARM. Try modifying the VERIFY romset to test only one flash. If it gives you OK, then you know the ARM is most probably good and you can narrow down the faulty flash.
I didn't even think of that. It looks like Flash 12 has a problem. It verifies OK on 0101 but fails on 1010. All other flash seem to verify ok.

Which flash is 12 on the multi board?

I saw in another thread the flash part number is GLS36VF3203-70-4E-EKE, but looks out of stock everywhere I order from. Is there an alternate?

I created the folder structure to test the flashes individually. Hopefully I did this right. I'll attach it here, might be helpful to someone else.
 

Attachments

  • verify_flashes.zip
    252.4 KB · Views: 227
Which flash is 12 on the multi board?
That's one of the GFX flashes. It's marked as U83.


I saw in another thread the flash part number is GLS36VF3203-70-4E-EKE, but looks out of stock everywhere I order from. Is there an alternate?
They are specially made for us. There is no alternate for now.
 
All I have is attached to multis I have here. No new chips of course.
 
Bummer. I’ll check the traces going to U83. If more of those chips come around please let me know.
 
If I swap U83 for another chip on the board which chip should I try? Maybe I can swap it for an audio flash to test if it fixes graphics...
 
I won't be in front of my computer for a few days, so can't say for sure, but if you change a PROM or Sound ROM it won't boot at all, try a Sample or GFX chip instead.
 
I won't be in front of my computer for a few days, so can't say for sure, but if you change a PROM or Sound ROM it won't boot at all, try a Sample or GFX chip instead.
I'll wait until you can confirm. Thanks!
 
I'm ready to take another stab at this board. @Darksoft - any chips become available or are you able to confirm which chip would be ok to swap in for U83?
 
U83 is a GLS36VF3203 from Greenliant.
Yes. But, as you said earlier in this thread it is custom made for you and out of stock anywhere I've checked. Maybe I'm misunderstanding, I apologize.
 
Got the chips, thanks @Darksoft!

I've replaced U83 and there was no change in graphics issues. Not sure where else to go with this. Can someone download the verify_flashes.zip I uploaded a few posts ago and try to load 10FLASH12 and 01FLASH12 to see what the result is?

My 10FLASH12 is still failing.

I went back and decided to pull out U40. When I got the board it looked like someone replaced it and destroyed the traces, but I only fixes the traces and never replaced the chip. When I removed it the pads were all almost all completely gone.

I might be ready to throw the towel in on this one.
 
I spent a little more time on this. I was probing the level shifters and U34 I/O pins 8, 9, and 10 are stuck low. I've already replaced this chip and I believe continuity is ok. These pins go to ROM13 A13, A14, and A15 (U28, U29, U77, and U78 pins 1, 2, and 3 it seems)

@Darksoft any idea what might be causing level shifter to be stuck or is this not an issue?
 
If its A and/or B board issue let me know. I have spares so can send a set your way to test on, just pay shipping :)
 
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