MGCD - cant get it to work! :(

[tetsujin]

Hi all

I just got a MGCD for my DC to play Under Defeat on my New Astro City.

Now I know that there not 100 JAMMA in tha fact that some of the buttons are used as gnd's etc etc

But I can get it to just make the controls work!

I have had a look at the dip setting etc on the net but still unsure of what to do.

Any help/hints etc?

[thechop]

Are none of the buttons working?You may need an adaptor as it probably thinks a button is pressed (something to do with a GND or summat,can't remember now)all the time, thus making none of them work.that was the prob with mine anyhow

Oh and i forgot i'm struggling to locate that pad hack your after,Fcuk knows where its ended up

[Dave_K.]

MGCD uses the last two connections of the Jamma harness for buttons 5+6 for both players, but standard jamma spec wires these to ground. The MGCD will barf all over itself if these buttons are grounded (or held down) upon bootup, resulting in no controls working.

To fix this, you need to extract the last two pins off each side of the jamma connector using a very small eyeglass or jewlers flat head screwdriver. If you do it correctly, you should be able to reinsert the ground pins later to restore the jamma connector back to normal. Another option is to create an MGCD adapter with fingerboard that passes through all jamma pins but the last two on each side. You can then wire these last ones up to a kickharness if you want to play 6 button fighters.

[tetsujin]

how hard and how much would this cost to do?

I only want to play Under Defeat on my Vert Astro City!

[tetsujin]

ok, if I make my own, its pretty simple in the fact that I just make up the pins the same except the gnd?

So, I need one of these....
http://www.jammaboards.com/store/jamma- ... rod_1.html

But what about the female end of the jamma connector?

[Dave_K.]

Jammaboards sells the edge connectors too:
http://www.jammaboards.com/store/56-pin ... rod_9.html

Quick and dirty solution: cut the last four black ground wires from the jamma connector which got to pins 27 and 28 on both sides of the jamma connector. Play your MGCD until you get board. If you want to go back to jamma games, splice the ground wires back together (twist the cut ends back together).

Long and dirty solution: make a fingerboard similar to this guy's


Long and clean solution: make a fingerboard similar to mine

[tetsujin]

hey dave, do you have a more detailed pic?

Ive ordered a blank finger board but not 100% sure on the wiring.

Cheers
Adam

[Dave_K.]

hey dave, do you have a more detailed pic?

Ive ordered a blank finger board but not 100% sure on the wiring.

Its very simple. I just soldered each of the connector pins to the edge board, except for the last 4 pins (on each side of the board). I then did something which is probably optional, which is link the last two edge connector pins on each side over to edge connector 1 which is ground. Note, this means the jamma loom gets grounds that it wants, and the MGCD does not see ground on the last 4 pins of each side. Hope that makes sense. If you still need a more close up pic I can take one, but the top most pic I do not have a better resolution shot of as its not mine.

[penrhos]

what did you do about the audio as it has stereo output and most cabs are mono?

[Dave_K.]

what did you do about the audio as it has stereo output and most cabs are mono?

I believe the DC system menu can change the audio to mono, otherwise most DC games have this option in their settings as well. Hardware wise, the MGCD AV cable will handle taking audio (and video) into the PCB and then amplify the audio out to the correct jamma pins.

[tetsujin]

hey dave, do you have a more detailed pic?

Ive ordered a blank finger board but not 100% sure on the wiring.

Its very simple. I just soldered each of the connector pins to the edge board, except for the last 4 pins (on each side of the board). I then did something which is probably optional, which is link the last two edge connector pins on each side over to edge connector 1 which is ground. Note, this means the jamma loom gets grounds that it wants, and the MGCD does not see ground on the last 4 pins of each side. Hope that makes sense. If you still need a more close up pic I can take one, but the top most pic I do not have a better resolution shot of as its not mine.

ok, I have all the parts ready to do this but, when you say the last four pins do you meen per side or in total? (TOTAL 8)




Cheers
Adam

[Dave_K.]

ok, I have all the parts ready to do this but, when you say the last four pins do you meen per side or in total? (TOTAL 8)

Last two pins on both sides (total 4).

[tetsujin]

ok, I have all the parts ready to do this but, when you say the last four pins do you meen per side or in total? (TOTAL 8)

Last two pins on both sides (total 4).

Cheers dude, I'm gonna start on this over the weekend

[penrhos]

If your going to IC-09 I might be able to knock one up for then....

[Catzoo]

Don't know if it's gonna help anyone , but if you're too lazy to build an adapter , just solder a wire between 1 and 2 and 27-28. This works on my egret 2 ( but with 4 buttons only )

And i didn't it only on the part side , but it works

[JoeTeach]

Got one of these yesterday and having similar problems here, can''t get any input due to the ground for pin 27 and 28.

I've read a few different solutions and want to check a few things:

-JAMMA pin 1 and 2 are ground as well as 27 and 28, are these grounds for different things or are they common? i.e. could I wire the JAMMA harness's pins 27 and 28 across to pin 1 on the PCB?

-What effect would taping over pins 27 and 28 on the PCB have? I'm wary of the lack of ground.

-pin 25 and 26 are designated as button 4 and 5 on the PCB but they have no designation for JAMMA harness - do I need to do some wiring to get them recognised?

Sorry, new to all this JAMMA stuff and picked a stinker of a project to start on it seems!

[Rossyra]

- On any electronic circuit there is only ever one ground (sidenote: some gamepads have trickery involved, but they are ultimately one ground) So yes, combine away.

- You could tape the edge, but don't expect that to last too long, a better idea would be an adapter rerouteing the grounds

- Yes you will need to wire 4+5 to the harness

[JoeTeach]

Thanks, I've done 360 padhacks before, hence my worries about grounding!

As Pin 25 and 26 are currently blank on the JAMMA connector, I assume wiring up these from the button on the CP straight to my JAMMA harness is fine, they'll just be redundant when a standard JAMMA PCB is connected? Also out of interest, does a Neo Geo mobo use Pin 25 for button 4 in that case?

Hoping the pin 27/28 grounding is what's causing my problems, it seems to intermittently press the start button, as it starts the game itself and then goes on to continually pause / unpause...

I'll mainly be using it for shooters, so 3 buttons is plenty for the most part while I get it up and running

[Rossyra]

Yes, that's right, and for NG too