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duffcon

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So I WAS psyched about a good deal CPS1 Street Fighter 2: World Warrior, until I open the box. Apparently these things are made out of diamonds.

3FBE92B9-DE18-4EE1-9474-430690449444.jpeg

it’s totally dead, nothing. Speaker probably bashed around the whole trip.

So before i demand a refund, I tried the normal CPS1 troubleshooting. I also have a Champ/turbo board and swapped the B/C boards to the working A board and also used the bad A board with my good B/C boards. In either case I get nothing.

anything else easy I can try?
 
Damn, how annoying. Doesn’t sound hopeful if swapping your working A and B/C sets aren’t working in either possible combination.

You could try reseating the EPROMs and flexing the boards slightly to see if that helps.

But definitely get your money back. That packing is pure negligence.
 
The seller refunded my money and told me to keep it. This person was kind of a dingbat so I really don’t think it occurred to them that a speaker bouncing around on it would damage it. I’ll look it over more to see if there’s obvious damage but I didn’t see anything on a quick look.
 
well, money back and a free broken board is at least a better position. but it would have been better if you could, i don't know, get what you buy for the price you agree on? i hope it ends up being fixable.
 
Look at all the ferrite filters labeled "FB" on the board. When they get broken off the B and C boards you'll have a dead duck on your hands.

Hell, sometimes you'll find them floating around the bottom of the box after they get broken off. :)
 
Check fb1-8, all there. Passed continuity. It occurred to me there might be broken bits in the box, but no clues
 
It's possible, but i don't think it is likely. it's more likely physical force from smashing around unprotected damaged the pcb. there are magnetic forces around us all the time, I don't think the magnet is that powerful, relatively. It is pretty heavy and dense though, so when it is shipped and bumped around continuously for days, it could easily break a component. Or even just flex the PCB enough to snap a trace or two.
 
Get the refund while you can.
Going to be a huge amount of effort to repair both A & B boards - on top of the cost you have paid for a fully working unit.
Different story if you bought it 'untested', 'junk', 'not working', but then it would have been priced accordingly.
 
So I sent this board out to a KLOV member who generously offered to take a look. It seems like the issue is the A board; which was riding on top of a switching power supply. Probably a broken trace. I may come back to this one one day if I get anywhere near competent about PCB repair.
 
I've been tinkering with this project recently. Trying to learn more about PCB repair and this board in general. I've been looking at the schematics and trying to continuity tests. I cannot make heads or tails of it.

I'm trying to follow the +5v input past the ferrite beads.

Pins 1-2 (groun) inputs go to FB1-4. But I can't even see past the JAMMA pins on the +5 input. Can anyone give some guidance? Some easy things to test for a dead board?

I know the the b/c boards are partially working by connecting to another A board. This A board is totally dead.

Given the stack design, the underside of the A board and the small section near the JAMMA edge on top are the only parts that are exposed really. I've looked over the underside and I can't see any broken traces.
 
Well, the CPS1 boardset is an odd one...

Take just the A board and plug it in. Check pin 107 of the CPS-A-01 chip for a clock. Schematics call it CK250. If that isn't working, the bus sharing that the 68K CPU can do doesn't happen and the CPU stays stuck in a state of waiting on another bus device. I ran into that on a board last month. That custom was bad.
 
I imagine you'd have to take the b/c board off to probe the A-01; is it safe to run the board this way?

*edit* I think I see a test point attached to pin 107 here:

1636564413981.png


1636564819246.png
 
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pin121 looks not soldered - others dont look right either - but it could be the picture.
 
Well, the CPS1 boardset is an odd one...

Take just the A board and plug it in. Check pin 107 of the CPS-A-01 chip for a clock. Schematics call it CK250. If that isn't working, the bus sharing that the 68K CPU can do doesn't happen and the CPU stays stuck in a state of waiting on another bus device. I ran into that on a board last month. That custom was bad.
So I probed the point I mentioned above and it read high, so I guess that means clock is a present? There was no fluctuation, just static high.
 
Nope... clock would be the red and green lights blinking on the logic probe. Stuck high is either a defective main clock or a bad CPS-A-01 custom IC, which is a common failure item.
 
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