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Main => Main Forum => Topic started by: Billy_Goatfeet on June 28, 2010, 09:23:56 pm

Title: Help with diagnosing JAMMA video glitches.
Post by: Billy_Goatfeet on June 28, 2010, 09:23:56 pm


  I wasn't sure which area to post this in so I hope this is appropriate.  I am looking for some help on this sad issue.  I had some boards in storage for some time and recently brought them out for testing.  Sadly more than half had errors of some sort.  I took some pics of the glitches in hopes that someone here might be able to suggest a path of action.  The boards in question are Mortal Kombat 3, Final Fight, NBA JAM, and Street Fighter 2.  I have also taken detailed photos of the boards if that can help answer any questions.  Obviously the best way to find out what is wrong is on a workbench with a technician but I don't think any of the games are worth spending money to have repaired.   Anyhow, enough talk, here are the pics...

MK3 - random large patches of scrambled graphics, sound was ok if I remember correctly.

(http://i42.photobucket.com/albums/e306/Flowry/Mortal3Screen.jpg)


Final Fight - Completely buggered, just the green twisted image.

(http://i42.photobucket.com/albums/e306/Flowry/FinalFightScreen.jpg)


Street Fighter 2 - The fighters don't ever appear and the upper half of the screen appears to be cut off.  The colours are also wonky.

(http://i42.photobucket.com/albums/e306/Flowry/StreetFighterScreen.jpg)


  And NBA JAM is just black, it doesn't do anything anymore.  None of the boards show any visible damage and I have checked for loose chips.  Is there anything here that can be salvaged?  Thanks in advance.


Billy Goatfeet.


Title: Re: Help with diagnosing JAMMA video glitches.
Post by: RayB on June 29, 2010, 12:24:00 pm
Is it safe to assume you tweaked the monitor settings? The Final Fight screen looks like a horizontal sync problem, which could simply be the monitor setting and nothing wrong on the board.
Title: Re: Help with diagnosing JAMMA video glitches.
Post by: Billy_Goatfeet on June 29, 2010, 03:06:35 pm


  You are correct Ray, I tried to unscramble the h-sync with the FF board but no luck.  These boards might be toast methinks!

Title: Re: Help with diagnosing JAMMA video glitches.
Post by: Malenko on June 29, 2010, 03:10:50 pm
does MK3 pass the EEPROM checks?
Title: Re: Help with diagnosing JAMMA video glitches.
Post by: Q*Bert_OP on June 29, 2010, 04:14:36 pm
Pull and reseat the ROMs and anything that's in a socket. Did these work before storage?
Title: Re: Help with diagnosing JAMMA video glitches.
Post by: Billy_Goatfeet on June 29, 2010, 09:37:34 pm
Pull and reseat the ROMs and anything that's in a socket. Did these work before storage?

  Yes, these worked flawlessly before storage.  I have never messed with a board before, other than cleaning it up.  What is involved with pulling the roms, do I need a special tool or do I just pull them out?


Title: Re: Help with diagnosing JAMMA video glitches.
Post by: Billy_Goatfeet on June 29, 2010, 09:38:49 pm
does MK3 pass the EEPROM checks?


  Great question to which I cannot remember the answer.  I will pop it back in and check!


Title: Re: Help with diagnosing JAMMA video glitches.
Post by: Billy_Goatfeet on June 29, 2010, 10:42:36 pm
Pull and reseat the ROMs and anything that's in a socket. Did these work before storage?

  Thanks, this worked for MK3 Ultimate.  It is working again, much appreciated!

 :applaud:

Title: Re: Help with diagnosing JAMMA video glitches.
Post by: Billy_Goatfeet on June 29, 2010, 10:44:10 pm
Is it safe to assume you tweaked the monitor settings? The Final Fight screen looks like a horizontal sync problem, which could simply be the monitor setting and nothing wrong on the board.


  I thought I would recheck this, and guess what, it worked.  Horizontal sync was the problem after all.  :-[

Thanks Ray!!   :cheers:

Title: Re: Help with diagnosing JAMMA video glitches.
Post by: Billy_Goatfeet on June 29, 2010, 10:47:16 pm


  So Street Fighter is still in the same shape as before, I pulled all the roms that I could and reseated them.  No change.  I did the same for NBA Jam and it still only sends a flickering black signal.  Two out of four ain't bad.  Thanks for you help everyone.  Anyone need parts for SF2 or NBA JAM?

 :cheers:

Title: Re: Help with diagnosing JAMMA video glitches.
Post by: Malenko on July 02, 2010, 07:13:58 am


  So Street Fighter is still in the same shape as before, I pulled all the roms that I could and reseated them.  No change.  I did the same for NBA Jam and it still only sends a flickering black signal.  Two out of four ain't bad.  Thanks for you help everyone.  Anyone need parts for SF2 or NBA JAM?

 :cheers:



any sound on NBA Jam? Does it boot if you dont hook the sound board up? I need an extra power cord and "mini ide cable thingie" from NBA Jam if you're getting rid of stuff =) Sound pot too if ya got it.
Title: Re: Help with diagnosing JAMMA video glitches.
Post by: Q*Bert_OP on July 02, 2010, 06:24:29 pm
On NBA Jam...make sure the ribbon cable is put on the correct way on both sides...red stripe goes to pin 1 on both boards. If nothing, unplug the board, remove the battery, wait at least 30 seconds, apply power to board again. Corrupt CMOS memory can cause the board to do strange things.

On SF2, it's a sandwich of 2 boards, right? Separate them, then reconnect.