Is the PS3 controller common ground or power for the buttons.

Neither.

http://www.mikroe.com/forum/viewtopic.php?...38441a20c040e5f

The PS3 controllers have 4 different lines for all of the buttons, COM1 for the D-pad, L1 and L2, COM2 for the X, O, [ ], /\, R1 and R2 buttons, COM3 for Select, Start, L3 and R3, and Voltage for the PS button.

If you're trying to make a duplicate button you simply connect the button to one side, X for example, then it's COM line, COM2 in this case, to the other side of the button and there is your duplicate X button.

If you're trying to do anything else you're in for a lot more work.

I was going to make a ps360 controller. I want to use a ribbon cable to connect the ps3 controller mobo to a seperate pcb il etch. Then put solder pads on the pcb and solder those to the xbox 360 controller button points. Then just rewire the stick pads on the ps3 controller to the sticks ill actually use on the xbox 360 mobo. Like you did RDC, but since the ps3 controller has a ribbon cable port for the button pad plastic cable thing, Ill take advantage of it.

The 360 board still has to be rewired into the PS3 layout, so you're really just adding more parts and unnecessary work going about it that way. First making the cable, and depending on which version PS3 controller there are 2 different ones, then some way to secure it if it's the latter version, which will only take up more room as will the etched board you plan to make, room that there really isn't once you have the 360 and PS3 boards, plus all the bare minimum wiring inside the shell.

Now if you were making an arcade stick going about it that way would be useful, because you have the extra room for it all, but that's already been done before for that purpose.

When i said rewiring the sticks i meant soldering of the ps3 ones, and soldering those terminals to the xbox 360 board stick terminals which still have the sticks. As for adding a pcb, i could just use a ribbon cable the plugs into the ps3 board socket and solder with the wires on the other end.

I didn't mean the sticks, although they're a mess all on their own if your PS controller has the newer Hall Sensor ones, I meant for the controller in general. No matter what 360 controller you choose none are in the PS layout for anything, so it's going to need traces cut here and there and then either rewired on the 360 board, or you use twice as many wires so you have 2 for each button.

I just don't see any advantage to having the ability to plug and unplug the connector on board like you're wanting to do, and it would only work on the older version Six-Axis controllers. The sticks still have to be wired up, as do the USB, LED and Reset button connections, so it's not going to make it any easier to swap boards if that ever arose, and if you went from an older PS controller to a newer one the connectors are completely different.

http://forums.xbox-scene.com/index.php?showtopic=648322

Making the connector for it will save you from having to solder 20 connections at most, not really a lot when compared to how many there are in total and it locks you into using the older version Six-Axis boards that don't have Rumble. Even if I were going to make one with the older version boards, I prefer the DS3 versions though, I'd still pull the connector and solder directly to the board. If you don't want Rumble you can just leave the motors out of the DS3 and it's the same deal.