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Main => Main Forum => Topic started by: BubNBob on May 26, 2015, 11:03:06 pm

Title: Not really sure how J-Pac can work
Post by: BubNBob on May 26, 2015, 11:03:06 pm
I just bought a lethal enforcers cab. It has a JAMMA board.

So here are my questions.

1.If you plug the J-pac in, can I wire 2 players with a joystick 6 buttons to it? This cab only has 2 start buttons and 2 light guns.
2.If I can't wire the J-pac with those buttons and sticks, can I use an I-pac alongside a J-pac?
3.Is it even worth it to have the J-pac if I need an I-pac? What advantages would there be of using a J-pac vs using no J-pac at all?
4.If I use the J-pac is it possible to use the light guns in MAME?

Thanks.
Title: Re: Not really sure how J-Pac can work
Post by: Malenko on May 27, 2015, 10:28:24 am
With the JPAC you get the JAMMA inputs of 1 stick per player, 3 buttons per player, 2 start buttons and 2 coin inputs. The JPAC itself has screw terminals allowing for 4,5,6,7 and 8 for both players. So theoretically 1 stick, 8 buttons, coin and start PER player.

You can use an IPAC with a JPAC if you need additional inputs but that is typically used for 4 player set ups.
The JPACs primary purpose is to use a JAMMA cab's existing wiring. You would still need to supply the JPAC with a valid video signal to display on the arcade monitor (groovyMAME, Soft15, ArcadeVGA,etc)

You cannot use the guns from lethal enforcers on MAME, they dont just plug into a PC and work like that.
Title: Re: Not really sure how J-Pac can work
Post by: BubNBob on May 27, 2015, 08:59:54 pm
So you are saying I wire the joysticks and 3 buttons each to the JAMMA board and then 3 buttons each to the J-Pac?
Title: Re: Not really sure how J-Pac can work
Post by: yotsuya on May 27, 2015, 09:08:48 pm
Are you wanting to run the original board & a PC in there at the same time? You're probably going to have some issues because Lethal Enforcers uses a mirror as part of the video setup. You'd have to do some image flipping on the PC.
Title: Re: Not really sure how J-Pac can work
Post by: BubNBob on May 27, 2015, 09:17:15 pm
Is that difficult to do? I'm going to use Windows 7.
Title: Re: Not really sure how J-Pac can work
Post by: yotsuya on May 27, 2015, 10:42:47 pm
I foresee this ending in tears.
Title: Re: Not really sure how J-Pac can work
Post by: pbj on May 27, 2015, 10:52:37 pm
I say go for it
Title: Re: Not really sure how J-Pac can work
Post by: dmckean on May 28, 2015, 12:33:33 am
Is that difficult to do? I'm going to use Windows 7.

Yes, get another cab.
Title: Re: Not really sure how J-Pac can work
Post by: yotsuya on May 28, 2015, 02:52:16 am
Is that difficult to do? I'm going to use Windows 7.

Yes, get another cab.

 :cheers:
Title: Re: Not really sure how J-Pac can work
Post by: Malenko on May 28, 2015, 07:44:35 am
Is that difficult to do? I'm going to use Windows 7.

Flipping the X wires on the chassis is easy to do. However, I dont think Lethal Enforcers is a very good cabinet for MAME.
Title: Re: Not really sure how J-Pac can work
Post by: yotsuya on May 28, 2015, 09:00:03 am
Is that difficult to do? I'm going to use Windows 7.

Flipping the X wires on the chassis is easy to do. However, I dont think Lethal Enforcers is a very good cabinet for MAME.

Yeah, he could do that, but it sounds like he wants to run both at the same time. So not only would he need a JAMMA switcher, but he'd have to screw with the monitor chassis each time he wanted to switch.

And I totally agree with the second statement.
Title: Re: Not really sure how J-Pac can work
Post by: BubNBob on May 28, 2015, 09:05:21 am
So I won't run both at the same time, just MAME. What other reason is it bad for MAME besides this one issue?
Title: Re: Not really sure how J-Pac can work
Post by: Malenko on May 28, 2015, 09:16:59 am
So I won't run both at the same time, just MAME. What other reason is it bad for MAME besides this one issue?
As long as you accept that the guns wont work, that there is some learning to do when using an arcade monitor with a PC, and you promise to replace the CP with a new piece of wood; you can totally MAME it.

Title: Re: Not really sure how J-Pac can work
Post by: BubNBob on May 28, 2015, 01:20:51 pm
So I might as well just use the I-pac (not J-pac) and switch the wires so it doesn't mirror. I still wanna use that monitor and the cabinet chassis.

I'll show you guys when I finish.


Title: Re: Not really sure how J-Pac can work
Post by: Malenko on May 28, 2015, 01:22:25 pm
So I might as well just use the I-pac (not J-pac) and switch the wires so it doesn't mirror. I still wanna use that monitor and the cabinet chassis.

I'll show you guys when I finish.

you need the JPAC to filter the signal to the monitor. It makes it easier to hook the computer to the monitor too, no JPAC and you'll need to use a VGA Breakout cable.
Title: Re: Not really sure how J-Pac can work
Post by: BubNBob on May 28, 2015, 03:00:54 pm
I'll ask my question again.

Do I need to wire 2 joy sticks and 6 buttons to the JAMMA board and then do the rest on J-Pac?
Title: Re: Not really sure how J-Pac can work
Post by: Malenko on May 28, 2015, 03:27:02 pm
I'll ask my question again.

Do I need to wire 2 joy sticks and 6 buttons to the JAMMA board and then do the rest on J-Pac?

Cool, I'll answer again:
With the JPAC you get the JAMMA inputs of 1 stick per player, 3 buttons per player, 2 start buttons and 2 coin inputs. The JPAC itself has screw terminals allowing for 4,5,6,7 and 8 for both players.

So yeah, you wire up the JAMMA connections then put the "kick button" wires into the screw terminals.
Title: Re: Not really sure how J-Pac can work
Post by: BubNBob on May 28, 2015, 04:12:16 pm
Thank you sir. Now I know exactly what to do.
Title: Re: Not really sure how J-Pac can work
Post by: yotsuya on May 28, 2015, 05:04:31 pm
I'll ask my question again.

Do I need to wire 2 joy sticks and 6 buttons to the JAMMA board and then do the rest on J-Pac?

This keeps throwing me off. Assuming you are going straight MAME, the joysticks and buttons are connected to the JAMMA harness, which in turn receives the JPAC. There is no JAMMA board as part of the equation. Just wanted to be clear.