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Main => Main Forum => Topic started by: mattr on June 14, 2005, 08:52:51 pm

Title: dc 2 jamma problem
Post by: mattr on June 14, 2005, 08:52:51 pm

Hi Eveyone,

I'm attempting the DC2Jamma project but I've run into a problem.

I have video connected but when I connect the pads they do not work correctly. If I connect the pads directly by-passing the fingerboard its fine. Audio is independent of the finger board.

It seems that the video connection is producing a lot of noise or induction which triggers the buttons.  I have checked all connections on the fingerboard and there is no contact between the various pins.

I have separated the video and power wires in the Jamma harness but this did not help. So I assume induction can be ruled out.

Any suggestions?

Cheers,
Matt

Title: Re: dc 2 jamma problem
Post by: pcb on June 14, 2005, 11:40:21 pm

How did you hook up the video?

Title: Re: dc 2 jamma problem
Post by: mattr on June 15, 2005, 06:18:19 am

I took the RGB+Sync+Ground from DC VGA box to Jamma finger board.

Title: Re: dc 2 jamma problem
Post by: Dave_K. on June 16, 2005, 01:56:05 am

I've never herd of this problem before.  Are you using seperate grounds for video and the button controls?  Video gnd should go to pin 14.  Button control grounds (from the pads) should go to one of the last 4 pins.

Title: Re: dc 2 jamma problem
Post by: mattr on June 16, 2005, 09:27:57 am

Video ground comes from the DC VGA box and goes to Jamma Video ground (14) while DC Pad ground goes to Jamma Ground (28).

I've disconnected everything and using a multimeter I  test for continuity and I have find that Video ground on the VGA box is the same ground circuit as the pads. I tested R, G, B and Sync grounds on the DC VGA box and the outer as well.

Looks like this is where the DC2Jamma page runs out of helpful tips! :-(

Title: Re: dc 2 jamma problem
Post by: mattr on June 16, 2005, 10:35:10 am

I've wired up a new controller and that seems to work fine. So I must have damaged both controllers when I wired them up. :(

Unfortunately the buttons on the new controller don't seem to operate in the same way so I can't get that fully operational either.

Well, back to it. Ikaruga fun factor is surprisingly high despite not being able to fire ;D

Cheers,
Matt

Title: Re: dc 2 jamma problem
Post by: Dave_K. on June 16, 2005, 04:05:09 pm

Maybe your controllers use multiple grounds?  Are they original sega pads or 3rd party?

Title: Re: dc 2 jamma problem
Post by: mattr on June 16, 2005, 11:34:20 pm

I've got two original Sega controllers. One made in 2000 and the other made in 1998. They are minor differences between them. When the controllers are wired up it seems like some or all of the buttons are being depressed constantly.

I tested various ground spots on the controllers and they were all common. I also tested for continuity between ground and active on each contact but couldn't locate any problem so I assumed the problem was caused by excess noise on the circuit.

I'm going to put the controllers back together tonight and check if they still work when in the plastic case.