I don't have a mame cab, but once in a while I like to play some games on it.the thing is I don't have an arcade controller, I just use a regular psx pad hook to a special usb port.
so I decide to see if I could hack this pad to one of my 2 single arcade controller that I've.
I got 2 like that, got it on ebay for a bargain , and never done nothing with it
then i open the psx pad (can be found for $3 on ebay)
i found out that it was a verry easy design.
when you have found the ground you just need to located all the buttons.
every conection is covered by a black coading, i just scrub it with the tip of a nife to make it easy for soldering. (if not solder wont stick to the pcb)
it took me 30 minutes to solder everything ...
then put everything back together...
and voila !!!!
i use that device so i can plug 2 psx controller !!!
now i can play mame and all my emulator ARCADE STYLE !!! and i can still use it on my playstation !!!