What's new

Clownkicker

Student
Joined
Jun 2, 2020
Messages
30
Reaction score
30
Location
California, USA
Having two issues with a Ghouls and Ghosts conversion:

https://imgur.com/a/tdV19qU

First problem: The missing vertical pieces on every sprite. Definitely a problem with the A board, as swapping to another A board makes the problem go away (bottom half of pic). Anybody have any experience with this particular problem? I'm hoping it's something other than "bad A custom", but I guess that's the obvious choice? Anything else to check besides that?

Second problem: The missing far background plane. Map screen also doesn't show up between levels. Problem is still there even after swapping out A boards and C boards, so it seems like it's likely to be the B board. Any ideas where to start looking? I've tried reflowing the connectors to the C-board, and even replaced one of the connectors to the A board.

Thanks in advance for any help!
 
First problem: A-board issue, def sounds like a dead custom to me... No fix other than to pull/rework another custom from something like a CPS2.

Second problem: Missing layers could be lots of things, but if the ROM test menu checks out, you've checked/replaced connectors AND swapped the C-board I'm at a loss for a proper explanation.
Maybe damaged traces on the PCB layer itself?
 
Thanks for the responses!

I was trying to avoid a QFP swap, but that seems like a likely candidate.

https://imgur.com/a/sZXfHo3

Got the chip off of the CPS2 board with some chipquik. That stuff is difficult to clean off after. :(

Tomorrow I'll try to see if I can get the other one off and swap them.

Thanks for the help!
 
Let us know how you make out with the chip swap- curious to see if that A-01 custom was the issue.
 
Now to try and figure out what's going on with the background layer on the B board...
Hows the ROM/self test menu report?
I feel like you should have at least one bad CRC, but depending on how its hashed I guess perhaps not.

I'm sticking with my original assumption of trace or socket damage on the B-board PCB itself.
 
Unfortunately, I haven't been able to actually see the startup self-test, because my set-up is supergun->xrgb->tv, and it takes a few seconds upon power-up for the tv to sync to the signal. By the time the video is displaying, it's already at the intro scene. :(

I just pulled and verified all 8 graphic roms against the daimakair mame set and they all come up verified.

Still looking for trace damage on the board. Nothing visible to me yet, but some of the traces run under components, of course.

Beginner question: What are these orange-ish FB components? https://imgur.com/a/B0wkdSG Is there a way to verify them?
 
Unfortunately, I haven't been able to actually see the startup self-test
Press the "test" button on your supergun and run the ROM test from the menu.

IE pin #15 on the parts side of a JAMMA harness
61Vign0xtsL._AC_SX425_.jpg
 
Weird, I’ve tried both the test and service buttons on two different superguns and they don’t seem to do anything with this board. 🙁. These buttons definitely work with other boards.

I was also able to hook up the board to a PVM and still don’t see a quick self test appear before the intro on boot up either.
 
On most (all?) CPS1 games Service button acts as a credit, but Test button should enter into the menu.
I know some (cheap) superguns don't have a button, which is why I included the pinout.
Not really sure whats going on if you can't access it... Maybe a DIP switch is locking it out (just guessing here)?

Pretty sure the self test at power on is very basic, only checking work RAM and program ROMs.
Test menu should be more robust (and may indicate a bad ROM/CRC, I'm kind of expecting that to be honest).
 
Looks like the test menu on GnG is activated by DIP-C, pin 8, but unfortunately there is no ROM test there:
https://imgur.com/a/DDBbjD1

That's okay though, I figured it out. The PAL at 11D was either bad, or the wrong type (it was unlabeled). I burned a GAL as a BPRG1 type, and everything works!
https://imgur.com/a/sgFLL3n

Thanks a ton for your help, @jassin000 !
 
Back
Top