Arcade cabinet sharing one GPIO controller?

[tommymsw]

I am sure this is covered somewhere, but I can't find it. I have a cabinet that I have had for over a year now, but I would like to be able to make it TWO player, while sharing the one GPIO controller setup. I assume I need to somehow set it up to share the controller but I will also need a button for "two player". (It is a retro machine and I really just do MAME type games on it... Pacman, DonkeyKong and so on). I have it set up now so the "Start" button chooses "one player" and the "select" button "adds credits". Do I need to add another button for a "two player" button? And then how would the system know that was the "two player" button?

[Substring]

@tommymsw I don't understand anything to what you said ... I guess you mean "2 players share controller 1 as they play one after another" ? If so, you should just map the P2 start on the GPIO

[tommymsw]

Ok, but when a start a game on MAME, it says "Press 1P or 2P". When I set up the controller (in recalbox) the button I choose as "start" ends up being the "1P" button and the "Select" button ends up being the "add credit" button. So how do I select "2P"? I don;t have or know how to assign a button so that Mame recognizes it as "2P" button.

[Substring]

@tommymsw as i said : you need a srart button on P2. In yoyr case, strictly follow the schema, you don't can't remap P2 in ES

[tommymsw]

@subs Yes, I guessed that I do indeed need to map a P2 button. That much I had figured on my own. I came here to see if anybody knew how I would go about doing this. I am guessing that some people must have a working P2 button on their machine. So I am just inquiring about how they went about this process.

[Substring]

@tommymsw you said you're using gpio ? The recalbox gpio driver ? So just wire tge P2 start button as explained in the wiki. Or you are not using that gpio driver ?

[tommymsw]

Ok, so I need to install ONE more button and map that new button to the P2 Start button and that will act as "choose 2 player" and then the ONE PLAYER joystick and all of it's buttons will work for player 2 automatically? So the ONLY button that needs to be set up for 2 player (one right after the other) is the P2 START button? Then when it is P2 turn, the joystick and buttons will work for player 2?

[Substring]

@tommymsw This is how i'm picturing what you're trying to do : single player arcade cabinet on which 2 players can play alternatively, right ?

So just give it a try : map one of your existing buttons to the GPIO P2 start button and see if it suits your needs

[tommymsw]

@subs Yea, I think that worked. Thank you. It seems as if you do NOT have to map both Joystick 1 and 2. It seems (so far) to be ok with using joystick 1 for player 2 also. At least in MAME and that is all I was looking for anyway.

Thanks for sticking with me. I think I expected it to be complicated and you expected it to be easy. You were correct. Now I just need to buy ONE more button and drill another hole.
Thank you.

[Substring]

One last thing : i don't think you need a seperate coin slot for P2. Such games are quite seldom, and mostly for games were both players play simultaneously

I'm glad I could help you This is what the forum is for