Neo Geo Controller Pinout - Why 2 D buttons?

Wiring up a neo pinout for supergun, I'm just wondering why there's 2 pins for D and which one should be used (I can only use one).

Thanks

 

You should use pin 4 for D and 9 and 10 for "E" and "F" if you have 6 buttons, but really it doesn't matter, when you connect it to a Neo Geo it will always make a "wired-AND" gate when you press 4 or 9.

 

Why can you only use one? You could connect D to both pins on the port. I did. And there was still room left to use 2 Not Connected pins for a E and F button.

 

Makes no difference, if you reuse the extra D though I guess you can have a "G" button heh

 

I can only use one because I am having 4 top buttons for jamma then 3 on the bottom for kick harnesses and the like.

Thanks

 

There isn't any difference, however on the Mahjong controller, Pin 9 is used as one of the matrix pins and Pin 4 isn't used.