How do I test if my controller is common ground?

Hello I have an old madcatz controller (my brother bought it when the 360 first came out and never opened it) that I would like to know if it is common ground, how would I go about testing it? also how can I tell if it is common line?


multimeter to test for continuity

Touch a ground from the USB section and put another point on another ground, repeat this for the buttons, directional pads, if there’s continuity on all ground points, then you’ll know its a common ground pcb.

thanks, how would I tell if it is a common line instead of a common ground?

I’m not sure what that means, i’m sure one of the more advanced electric guys will be able to tell you :slight_smile:

If the controller is a USB controller then where the USB connects to the PCB there should be a black wire. That will be common ground on the PCB. If you do a continuity test from that point to all the buttons on a common ground controller at least one side per button and direction will pass a continuity test.

On a common line controller there are groups of “commons” that where that common line is a certain linked voltage. For example there is this dreamcast controller that I had where the d-pad has a Common line between all of the directions and the signal. Start, A and B had a different common, and X and Y had a common.

Common lines unlike common ground contain a certain voltage and are linked. In a common ground PCB ground means that the voltage is 0 and will sink the voltage down. In a common line one common can be 4.5 volts but linked to a different part of the IC however it may be programmed. If you where to do a multimeter test on a common line to the ground you would find a random voltage.

So to sum it up if at least one side of each button can pass a continuity test to the known common ground it is a common ground controller. If not then it is common line.

There is a good chance it might be common line.

As rtdzign said, that’s how you test. Old madcatz controller probably isn’t common ground. Search for a madcatz 4716 (triggers require inverting) or get a 360 fightpad (triggers don’t require inverting, easiest padhack, but a little more expensive). That way, you’ll know for sure it’s common ground, in case you don’t happen to own a multimeter.

looks like it is not common ground, thanks for all the help guys. I am not planning to make a fight stick I want to make a ps3 controller into a 360 controller so I think I will see if I can get one of those madcatz controllers, I am not sure if a wireless 360 pad would work I’m not sure if there is a 5v line to power the ps3 PCB

If you’re not dual modding, you don’t need common ground. Common ground is only if you want to use multiple PCBs. You can use a 360 PCB that’s common line by itself. The contacts work the same. But instead of having ground and signal, it’s common and signal. The principle of the contacting the two ends of the metal is still the same, it is just handled differently than common ground. But like ps3 wireless sticks using AXISADAPTER aren’t common ground. You need a Leo board to do double wireless, because it makes PS3 PCB common ground. Microsoft wireless is common ground, except in triggers, but this doesn’t matter if you’re not dual modding. Wireless works at much lower voltages.

If you do not know how to check if a PCB is common ground, then conveting a ps3 pad to xbox 360 I think is waaaaaaaay beyond your skill set electronics wise.

You should really just get a dualshock 2 and use a 360 Joytron convertor.

To fit a 360 pad you would have to know how to cut it up and rewire any circuts you removed, Ben Heckendorn style. What makes this project so hard is that there is no space inside the DualShock 3 to shove the 360 pcb. You also have to keep the dual shock 3 pcb and all parts intact if you want the same feel of the pad. The fact that the DS3 uses a membrane conductor complicates things

I don’t want to say you can’t do it, but I wouldn’t feel right if I didn’t tell you, you are attempting a project that is mission impossible. I know if I tried this mod there would be a 98% chance of failure.

I have some of those Komodo controllers from meritline comming in the mail, was planning to go Wiimote style drill some holes in the top of the ps3 pad case and run some wires into the 360 board, gonna take out the motors in the 360 pad to make room for the wires. I figure the worst that happens is I waist a $7 controller and a couple feet of wire.