Neo Geo Pinout

I have wired up a few controllers for NeoGeo now, and I still don't know why pins 9 AND 4 are labelled as "D Button" since you only need one (AFAIK)

Does nayone know why both are included? When wiring up controllers I only ever use one of the pins.

HEre's what I'm talking about:

Amano Jacu said:

You don't need any "PCB from a Neo Geo pad or stick", you just need a DB15 cable and follow this pin-out:

http://www.gamesx.com/controldata/neocont.htm

Code:

1	Common (GND)	10	NC
2	NC		11	Start
3	Select		12 	C Button
4	D Button	                13	A Button
5	B Button	                14	Left
6	Right		15	Up
7	Down
8	+5v
9	D Button

Then it will work in your Neo Geo.

Click to expand...

We have discussed before about this. You can use any of the two pins 4 and 9 as D button, they both are the same. You can choose any of them. I personally use just pin 4 and it has always worked. Some people claim that it is better to have both pins wired to the same button, though.
The reason? It might have to do with how the Mahjong controller works. Seriously, no idea.