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NeuronFire

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TLDR: Would 5.24~5.25 volts fry a CPS2 A+B board, resulting in a black screen at start up?

I apologize in advance for not performing the best test practices when diagnosing the initial graphical glitches I saw. I should have done one thing at a time, and checked, taking notes and pictures as I went. I didn't.

Symptoms:
1. Black Screen on Power-up.
2. No Sound when triggering coin switches.
3. These symptoms persist when connecting the game to a known good cab at work running a CPS1 game (Street Fighter2 ` hyper fighting)

History:
I purchased the game on eBay and drove down to Arkansas from Seattle, WA to pick it up. This seemed like a good opportunity for a road trip. When in Arkansas, I did the following:
1. Played the game a few times to make sure it was operational. It was already running when I got there.
2. Opened the back of the cabinet to verify that CPS2 boards were there and what color they were. Based on screen shots, I expected the B board to be blue.
3. Examined the overall condition of the cabinet.
a. Prior to being refurbished by the reseller, the cab had been stored in a warehouse and exposed to moisture at least on the floor. The feet are rusty, there is some delaminating of the plywood at the bottom of the cab, and some yellow lichen.
4. The monitor appeared to be in good shape.
5. The cabinets internal wiring harnesss seemed in good shape, if dusty. Everything was arranged cleanly, with zip ties to keep bundles in place.
6. Closed up the cabinet, wrapped it in a plastic tarp (it was raining in AR) and then wrapped that in pallet packing wrap (that clingy stuff).
7. Loaded it into the van on its back side and secured it.

I then drove the 2600 miles back to Seattle over the next 2 days. I left on a Sunday at 2pm AR time and arrived home Tuesday at 4:30 pm. Had dinner with the wife and went to sleep.

The next morning I unloaded the cabinet into the garage and unwrapped it. I plugged it in and powered it up. It took a couple of on/off cycles before anything happened, but then it booted up with the following symptoms:

1. Scratchy, yet understandable audio. It seemed like there was a series of stuck bits either high or low in the samples.
2. Some texture data suffered from jail bars. Background data appeared fine, and the most foreground data was fine, but near background data and certain icons on the character screen suffered from XOR'ed out jail bar effects.


I ran through the all of the test options on the game and the RAM checks passed and the audio problems seemed consistent to my earlier assumption about the stuck bit. I tried cycling the power on and off a few times and waiting about 30 minutes and re-cycling the power to see if that would resolve anything. As expected, it didn't.

This is likely the point where I started messing things up:
1. I removed the CPS2 boards from the cabinet. Separating the JAMMA harness from the plug was way harder than I expected. Subsequent disconnections are much easier.
2. I separated the A from the B board, (they still had the two clamps securing both boards together), and removed the B-board.
3. Both boards still had the Capcom 'C' security bolt in place. But a quick google indicated that I could remove the B board from the case without removing the the security bolt. So I did that.
4. I immediately noticed that the battery was missing, indicating that the board had been pheonixed instead of battery swapped as the seller had indicated. I talked to the seller, and I believe he was unaware of the nature of the "fix" when he got the board repaired. Also the 3a,4a,5,6,7 chips are were not the Capcom originals, but versions made by both NEC and TI. While these are all of interest, I didn't worry because I know the game had played fine with these ROMs. I turned off all of the most of the lights in my home office and applied new electrical tape to the top of the ROMS as the previous was poorly applied and peeling up in spots.
5. I dusted off the pcb with a compressed air duster and kimwipes with alcohol. I was worried because the dust + moisture from its earlier storage resulted in a kind of "mud" debris being present around the case in particular.

I then set to work on the A-board. I had to drill out the C-bolt because the fan area had tons of the mud gunk and the whole board smelled musty. Upon opening the housing, I cleaned the PCB with kimwipes, a duster and alcohol and washed plastic case with a mild soap and water and let dry. I then hit it with a hair driver set on no heat to get the last bits.

I put everything back together, connected the Jamma and kick harness back up and proceeded turned everything back on. That's when I got the results I described at the top: Black Screen, No sound when triggering coin switches. I power cycled a few times, waited, power cycled some more, and no change.

I figured that it may be possible that the ROMS were corrupted when I was changing the tape, so I began to search for replacement ROM data.
1. The Phoenix edition logo wasn't present when the game loaded, so to me that meant there was another decrypted version out there. I found what I believed was it on http://cps2.avalaunch.net/.
2. I checked the downloaded the updated roms and proceeded to examine and flash each of the ROMS. ROMS 3a, 5, and 7 didn't match the downloaded files, so I reflashed those and verified them.
3. I replaced the ROMS and re-assembled everything and turned the power supply on. Same result.

We have a Street Fighter 2' Hyper Fighting cabinet at work, so I took the cartridge there to see if my monitor or power supply was toast, but I blackscreened there as well.

I looked on various forums about black screens on CPS 2 boards and tried the suggested fixes of re-phoenixing and discharging capacitors, but many of the tasks disagree over which caps to discharge, I've discharged them all (I believe)

Next up, I began to examine the Jamma Harness and power supply, here's what I've discovered so far:
The +5V pin on the solder side (pin C) and the +12V pin on the Components side report 0 volts. This doesn't seem like a problem to me, since a connectivity test on the PCB shows that all appropriate power and ground pins on both sides have connectivity. On the parts side, the -5V pin and one of the ground pins is missing entirely from the harness. A voltage check with the board disconnected yields the following voltages:

1. +5V = 5.24~5.25 volts.
2. +12V = 11.44 volts.
3. -5V = 5.05 volts.

The +5V voltage seems quite high, and I worry if this has fried the board. I know current 5V MCUs can deal with a range between 4.5 and 5.5 easily but this was 1993 era hardware.

I'm picking up another CPS2 game this weekend as well as a new HAPP power supply (the 200 one with 2 switches: http://www.ebay.com/itm/111600670945) I have one of the winit (https://amzn.com/B01C5E8W3K) ones as well, but I'm nervous about its quality in comparison...

If the board is fubar, I figured I did it either invadvertently with the ROM flashing or some ESD damage, or the power supply killed it. It's also likely that the Jamma Harness is busted, I haven't done a connectivity test from the harness back to the powersupply yet, but that's on the list of steps.
 
It sounds like your ROMs and possibly the connection between the A and B boards became loose during the long journey from the seller back to your place. Before trying to flash code back onto the ROMs did you try reseating all of your ROMs to check and make sure that wasn't the issue? I would also consider erasing and reprogramming ALL of the decrypted ROM set rather than just the 3 that came back as not correct.

You definitely did the right thing cleaning out the cases, I clean out mine when I buy them as in particular the A boards due to the fan are pretty gross.

That voltage is high, but it may not have killed your board, you really need a known working A+B set so you can find out for sure. I see that you're now getting another game so you can test with that, I assume they're both the same region? (Blue/green are interchangeable, orange and grey require a matching A and B set)

A good power supply is never a bad investment. Hopefully your cheap one hasn't caused irrepairable damage. Before you plug in the CPS2 game you have just bought make 10000000000000000000000000000% sure that you have checked the voltage and it's as close to 5v as you can get it. If you have fried that board with too much voltage, don't make the same mistake twice.

Is it at all possible that water penetrated the board on the journey back? That wouldn't go down well when you powered it back on.
 
Voltage shouldn't really be measured when there's no load. That's why you should have some cheap spare jamma game for testing. Plug the test board, adjust voltage.

TLDR: Would 5.24~5.25 volts fry a CPS2 A+B board, resulting in a black screen at start up?
I'm going to say no to this one.
 
Some good news:

It looks like the damage is limited to the A-board. I updated the power supply to ensure that less than 5-V (4.89 at load) was being run, and was able to run the game using a JPN A-board.
 
That's good news I guess, hopefully the damage to the A board can be fixed (hopefully it's an issue that happened in transit rather than power surge)
 
@xodaraP, I don't think it was the transit, unless the transit shook some of the gunk that was in the board, loose. It was pretty bad. The fan blades on the back had at least a millimeter of the mud on them. And it was all over the vents on the board. I'm guessing my attempts to clean the board may have been the final straw. It still draws 5V power when connected, so some of the chips may be good still. But it's more time than I have right now to dig into it, given that I have a working Japanese board. Next up is a tear/down clean-out of the cabinet. And a replacement of the jamma harness and power supply.
 
I've got an NBA Jam and UMK3 that had far too much voltage run through them and they don't work properly anymore, the UMK3 just goes into a boot loop (I'm keeping it for potential parts on my working UMK3 though) and the NBA Jam is just a black screen even though it seems to be running through the tests and looping the test screen.

The coin counter on my Astro ticks over when it's connected and trying to run, I've tested almost all of the logic on the board and it's all tested good so far so I'm thinking the custom video processor is probably fried.

Could be a busted video custom here? If that is the case it'd still be worth keeping for parts.
 
My MK2 boot loops if my voltage is too low... I have to set it to about 5.18v to prevent this.
Happens just after ROM check/test screen most often, but sometimes mid testing.
 
Yeah, this is different, I put the working UMK3 next to the other one to confirm it and adjusted the voltage on the non worker, the non working one black screened with any higher voltage

Then I saw the NBA Jam damage and realized what the issue was likely to be (same seller)
 
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