What's this crazy Tekken 2 wiring?

[MartyNg]

I'll start off my saying that all every button on the control panel works fine playing the Tekken 2 JAMMA cartridge. I've got my JPAC hooked and was running the WiniPac test software and found some interesting things out. I understand that the JAMMA harness only supports 3 buttons per player, but I'm a little stumped here. The Tekken2 Jamma board has another small connector next to the JAMMA harness, which I assumed was for button 4 for both players, but that's where the confusion starts..

Through the JPAC test software:
P1 Start, P1B1 and P1B2 all register normally.
P1B3 and P1B4 do NOT register (--BINGO! Either that, or I was attempting to say "before" but it was too many letters to type-- wouldn't go through JAMMA anyway, of course) HOWEVER, when I hit P1B3 + P1B4 TOGETHER, it registers on the JPAC as P1B3! How can this be if neither register through the JAMMA harness?

P2 Start registers. No other player 2 controls register.

I was assuming that all of my controls (save Button 4 for both players) would go right through the JAMMA harness and work great through my JPAC. I would then wire the button 4s directly to the JPAC.

Can anyone explain why this works as it does? Did the previous owner wire it funky? I was hoping to not have to build a custom CP or not do a lot of wiring at this point. Thank you for any pointers.

[mrcram]

yeah that is weird    I suggest you do what I did and just buy a brand new jamma cable off ebay for $10 then you knew where every wire is and its nice and clean inside your cab.

[MartyNg]

yeah that is weird    I suggest you do what I did and just buy a brand new jamma cable off ebay for $10 then you knew where every wire is and its nice and clean inside your cab.

Good idea. That might be easier than tracing all the current wiring. Isn't that still unusual though that Player 2 doesn't go through the JAMMA harness?

I wonder if the JPAC isn't working correctly. Perhaps some of the terminals are shot? I'll have to get inside the cabinet sometime this week and see what's going on with the wiring.

Has anyone ever had a JPAC that had some non-working terminals?

[Kevin Mullins]

It appears that Tekken 2 has two buttons per player going to the smaller auxillary connector. P1B3 + P1B4 and P2B3 + P2B4
You could possibly move those wires over to the main JAMMA connector and then remap the buttons. (button 3 & 4 for each player)

Tekken 2 Pinout
http://www.crazykong.com/pins/Tekken2.pin.txt

Look here for where button 3 and the "optional" 4 normally go on the JAMMA harness:

JAMMA Pinout
http://www.coin.demon.co.uk/jamma.htm

[MartyNg]

It appears that Tekken 2 has two buttons per player going to the smaller auxillary connector. P1B3 + P1B4 and P2B3 + P2B4
You could possibly move those wires over to the main JAMMA connector and then remap the buttons. (button 3 & 4 for each player)

Tekken 2 Pinout
http://www.crazykong.com/pins/Tekken2.pin.txt

Look here for where button 3 and the "optional" 4 normally go on the JAMMA harness:

JAMMA Pinout
http://www.coin.demon.co.uk/jamma.htm

Cool! Thanks for the links. That's the wiring that I expected to find, but perhaps this is not the same cartridge that was used on that page since none of the player 2 buttons or directionals work (only the P2 Start button). Are there ever different 'minor versions' in JAMMA PCBs? (i.e.  Tekken 2  1.0  and Tekken 2 1.1, in which the games appear identical but actually have slightly different wiring?

Thanks for your help! 

[Kevin Mullins]

Well.. you kinda throw me off a bit every time I see you use the term "cartridge".... I hope we're talking about the same thing.
This is a typical Tekken 2 "PCB". (Printed Circuit Board)
http://www.crazykong.com/pcbs/T%20-%20Z/Tekken2.pcb.html

Aside from that... I wouldn't expect them to change the wiring setup just because of a minor revision to the program if there are any.

Trace your wiring from the player controls TO the harness connector and see if they match the pinout I found.
Then go from there, whether or not to move them to the standard JAMMA connector so the JPAC will interface with them.

[MartyNg]

Well.. you kinda throw me off a bit every time I see you use the term "cartridge".... I hope we're talking about the same thing.
This is a typical Tekken 2 "PCB". (Printed Circuit Board)
http://www.crazykong.com/pcbs/T%20-%20Z/Tekken2.pcb.html

Aside from that... I wouldn't expect them to change the wiring setup just because of a minor revision to the program if there are any.

Trace your wiring from the player controls TO the harness connector and see if they match the pinout I found.
Then go from there, whether or not to move them to the standard JAMMA connector so the JPAC will interface with them.

Yes, by "cartridge" I mean the PCB. (I'm a console gamer at heart)    Hopefully I will have a chance to go through all the wiring in the next couple of weeks. By re-wiring those few buttons, I will be effectively breaking my Tekken 2 capability, but will be able to play other JAMMA games that are more standardized in the contorl scheme. Is this a correct statement?

[MartyNg]

Through the JPAC test software:
P1 Start, P1B1 and P1B2 all register normally.
P1B3 and P1B4 do NOT register (--BINGO! Either that, or I was attempting to say "before" but it was too many letters to type-- wouldn't go through JAMMA anyway, of course) HOWEVER, when I hit P1B3 + P1B4 TOGETHER, it registers on the JPAC as P1B3! How can this be if neither register through the JAMMA harness?

P2 Start registers. No other player 2 controls register.

I spoke with Andy at Ultimarc and he informed me that a chip on the JPAC was defective. So if any of you see similar problems, give him a holler!