Build Your Own Arcade Controls Forum

Main => Main Forum => Topic started by: GCS on June 14, 2004, 09:42:42 am

Title: J-PAC Question
Post by: GCS on June 14, 2004, 09:42:42 am

Alright so it looks like you guys may have talked me into keeping the cabinet I have intact with the arcade monitor and JAMMA boards.

My question is if I get the J-PAC in there so I can go MAME with it can I still play the game in the machine??

How does it all work ... do I leave the computer off to play the game or is there a switch to switch or what??

Thanks for the help in advance.

Greg

Title: Re:J-PAC Question
Post by: krick on June 14, 2004, 11:21:20 am

You should check out this thread.  I think it will answer some of your questions...

http://www.arcadecontrols.org/yabbse/index.php?board=1;action=display;threadid=19899 (http://www.arcadecontrols.org/yabbse/index.php?board=1;action=display;threadid=19899)

Title: Re:J-PAC Question
Post by: microwrx on June 14, 2004, 09:17:30 pm

Just think of your PC as a non JAMMA PCB.  To connect it to a JAMMA cab you need a converter.  The J-PAC is your converter, it ensures all the right connections from your PC go to the right pins in the JAMMA edge connector in your cab.

To switch from J-PAC to JAMMA PCB just power off the cab, unplug the J-PAC, plug in your JAMMA PCB and power back up again.

The hardest part is figuring where in the cab you're going to put everything AND be able to access it all easily.

Title: Re:J-PAC Question
Post by: SirPoonga on June 14, 2004, 09:58:58 pm

You also need an arcadevga for the video.

Title: Re:J-PAC Question
Post by: microwrx on June 15, 2004, 01:48:53 am

Quote from: SirPoonga on June 14, 2004, 09:58:58 pm

You also need an arcadevga for the video.

Oh yeah....I'll just say I assumed that was part of the PC and not that I forgot to mention it.  Oops, too late! ;)

Title: Re:J-PAC Question
Post by: GameDork on June 15, 2004, 02:42:24 am

Quote from: SirPoonga on June 14, 2004, 09:58:58 pm

You also need an arcadevga for the video.

Ultimarc says you don't need one of these do they?

I think the Project Arcade book says you don't either.

I was under the impression that the J-Pac took care of the video too.

Title: Re:J-PAC Question
Post by: microwrx on June 15, 2004, 03:51:21 am

You don't NEED one but you are better off with one.  You need a video card that can send a 15kHz signal though.

The J-PAC amplifies the video signal from the PC video card and delivers it to the correct pins on the JAMMA edge connector.  It can split a 31kHz VGA signal in half but you then end up with two images on the screen but to be useful you need to send it a 15kHz signal.

It's main function is as a keyboard encoder like the I-PAC but enabling connection to a JAMMA edge connector so you don't have to rewire the cabinet.

Title: Re:J-PAC Question
Post by: SirPeale on June 15, 2004, 07:13:08 am

There are a lot of video cards that can output a 15 KHz signal.  However; only two that I know of that do it in Windows: the ArcadeVGA and cards based on the Trident Blade T64 chipset.

What I want to know is why more people haven't written these drivers.  The information is certainly out there.