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FIXED!!!!! MVS Repair: Warped PCB repair ideas? (No longer warped, still bad sound)

Well since March the game started mostly working for a while there, and now it's flat dead. Grid is all I get. Ordered a couple ZMC's off of aliexpress in a hope that they'll be useful, and am going to pull the chips to check against MAME this evening.

Got another non working MVS cart on the way, so may as well get this one running too.
 
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So my P1 comes up as a faulty device no matter what I do. That explains some things.

Took a stab at SP-2, it's a TC5332205, ran it as 27c322, read the file out, and it's correct. Not booting without P1 working makes sense to me. Will see if I have a 27c800 laying around.
 
Replaced P-1 with a doubled file from MAME on a 27c160.
Replaced SP2 with the file from MAME on a 27c322 since it kept giving pin issues and I figured it was worth it.

Still a grid.
 
Reflow of NEO-273 has me back up and running.

The voiceover in the beginning of the game gets scratchy, as do the grenade explosion sounds and a few other things still. Like staticy.

EDIT: And now it is WILD. Full on 50s movie robot sounds.
 
Replaced S1 and M1. One of them wouldn't read at all, the other didn't match up with the MAME rom.

Reflowed all the LS chips and the ZMC while I was there.

The SAURUS sound at the beginning still comes up as static, as well as the voice-overs in the intro, and the intro sequence music is all wrong.

Stage 1 music/sounds all are good though.
 
Looks like having read @channelmaniac 's repair logs that V1 and V2 contain audio data. The fact that I'm missing only some sounds makes it seem reasonable to pull V1/V2 and compare them against MAME.

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All 3 of V1/V2/V3 had issues. Replaced all 3.

Sound is even closer to right, but still not there. Guess I'm on to replacing the PCM and/or ZMC next.

ZMC's were 2 bucks a pop so I grabbed a few. And I ordered Furrtek's PCM replacement.
 
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yeah:
V-Roms contain audio samples, these are decoded through the NEO-PCM
M-Rom contains the music program which runs through the ZMC to a Z80 on the mobo

P-Rom is the main game program
C-Roms are sprites and ties
S-Roms are also related to graphics, essentially (tile location data I think)
the C and S-Roms are decoded through the NEO-273

So the audio is simple. if things are playing at the correct time and "trying" buy the samples are f-ed up then it's a good bet that the M-ROM and ZMC is good and your problem is with the V-ROMs or PCM

as I mentioned previously I had a batch of "dead" carts all with the same garbled, distorted sample sounds that you're experiencing and every one of them was a dead PCM chip.

depending on your specific cart there's some logic ICs to help with bank switching on the V-ROMs, that could also be a culprit, but less prone to failure than the PCM.

Also note that the V-ROMs are 8-bit so while some of them are 32Mbit in size (like a 27c322) you cannot use a 27c322 replacement since the 27c322 doesn't support 8-bit mode.
 
twistedsymphony said:
Also note that the V-ROMs are 8-bit so while some of them are 32Mbit in size (like a 27c322) you cannot use a 27c322 replacement since the 27c322 doesn't support 8-bit mode.
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Then what should I be using instead? As 2 out of 3 of them I've already replaced with 27c322 and the other with a 27c160 since 2 would not read and 1 had damaged data.
 
you can reconfigure the board for 160s if there's enough room for them (each 322 would get replaced by 2x 160s) beyond that you'd have to look at some kind of custom sub-board ROM module, there's some gerbers floating around but it's a pretty ugly, expensive and pain-in-the-ass solution.

Edit ...also you can't dump them as 322s either. so there's a good chance they're good and you just read them wrong
 
For reference to dump them you'd basically have to exclude the high address pin from the programmer (not 322 A20, it's be A21, a different pin), dump it once while tied high, dump it again while tied low. De-interleave both files to throw out all of the high bytes and then concatenate the remaining data together.
 
for reference, what game is this? or at least what PROG and CHA boards is it on?
 
twistedsymphony said:
you can reconfigure the board for 160s if there's enough room for them (each 322 would get replaced by 2x 160s) beyond that you'd have to look at some kind of custom sub-board ROM module, there's some gerbers floating around but it's a pretty ugly, expensive and pain-in-the-ass solution.

Edit ...also you can't dump them as 322s either. so there's a good chance they're good and you just read them wrong
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I think there are 5 V rom spots. Just half v1 and v2 so they'll fit on 160s, and I assume I need to change come jumpers as well?

EDIT: Upon opening it there are only 4 V ROM spots, so I need to just hope these are good and put them back...

twistedsymphony said:
For reference to dump them you'd basically have to exclude the high address pin from the programmer (not 322 A20, it's be A21, a different pin), dump it once while tied high, dump it again while tied low. De-interleave both files to throw out all of the high bytes and then concatenate the remaining data together.
Click to expand...
What a mess.
 
yeah those are the largest capacity non-encrypted PCBs. and (IMO) the easiest to work with. if you have a cheap or junk game on a PROGBK1 you could just ROM swap it and make sure the jumpers are configured right, that would help test the ROMs and confirm function or malfunction of the PCM.

I hope you got a good price on a non-working cart because this is way too much BS to deal with for having paid full price on an easily sourced game.
 
Well, I'll put the lower 2 V roms back today, and shelf it until the Furrtek PCM replacement shows up.

At least this resulted in the game running again as P1 / SP2 / M1 / S1 all needed to be replaced anyhow..

I do wonder if since the cart was warped so badly that fully removing and putting back on the PCM chip would solve anything. I'm not sure it's worth the effort though when I already have a replacement on the way.

Unfortunately just went through the JammaNationX list and don't have any of those that were on the less pricey side.
 
I have a BK1 board you can have.

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Its originally from some bootleg from a long time ago. It looks in good condition, but can't say for sure its 100% functional.
 
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