Is it possible to unify two different GND signals?


#1

Let me preface this question with some background first: I have a PS3 PCB I want to use to dual mod a X360 Brawlstick. This PS3 PCB has FOUR (technically 5+ but for our purposes it’s 4) GND signals. These GND signals are common to their respective areas (joystick, L1-L2, remaining 6 buttons, Start-Select-Home) but not with each other (GND wire for Start button wouldn’t be compatible with the signal for Square, for example).

For reference, here’s a wiring diagram I quickly made for my own use. In red are the ground points of interest:

http://i.imgur.com/w9cDcUr.png

This presents a problem because the GNDs for the buttons are “uncommon” with each other, but they need to become common in order to work correctly with the X360 PCB. Is it possible to remedy their differences and unite them as a people?

Disclaimer: I am aware I can just buy the non-assembled version of the Cerberus or a ChImp and be done with this for practicality’s sake. I just don’t like letting things go to waste.


#2

yeah of course anything is possible. though what you’re asking to do requires a firm understanding of electronic circuitry. the project leo board made by akihabarashop was able to make the sixaxis pcb common ground and suitable for dual mods. it would take many hours to study up and assemble the separate board you would need to make this pcb common ground. you’re really just better off buying a chimp or fightpad.


#3

And that all ready assuming the OP has very good knowledge on how electronic circuits work.

@VietGeek do you own a multi meter?


#4

Yes, I am aware what I am asking to do is conceptually taxing but very much possible.

@Darksakul: I do not personally own one. I can easily run to Radioshack and purchase one, however. I think I know where this is going.

Found this thread: Connecting Seimitsu LS32-01 or Sanwa JLF to non common ground xbox360 pads

Seems like the answer I need. Will engage in further research. Looks like I’ll be getting my electronics education after all.

Probably gonna end up making this a work log thread.


#5

I don’t know jack about electronics but what would happen if you soldered a direct line between each of the ground points?


#6

Doesn’t work, sadly. Without a multimeter on hand, all I’ve figured out is that the signal lines on for the respective common line [non-related GNDs] section (see first post for how the PCB divides the buttons) poll for different voltages or something to that effect. Combining all the GND to one wire “cancels” them out (assuming the one with the strongest voltage technically take precedence). Tapping into the USB GND is no good either; caused a short the last time I tried.

It’s definitely time for my household to own a multimeter.


#7

The word for those is “common” not GND. Ground is ground. Common is common. The kind of board you wanted was a common-ground (meaning, uses ground for common), but what you have is not common-ground.

@Coffeejuice gave you the straight business, without a lot of electronics knowledge and world you’re not dual-modding with that board since the common lines are not ground.

And considering you don’t have a multimeter, while a multimeter is a great tool to have, you could spend that money on a Cerberus or other PS3 equivalent board that is common ground and not have to mess around with that board. Kind of time and investment vs. return consideration, and going with a different board will be your best return on investment.


#8

Thanks for the terminology clarification. I have other uses for the multimeter as well, not to mention the value of understanding some more intermediate level circuitry from taking on this task and (hopefully) completing it.

This is just a project stick that I am in no rush to complete.


#9

^ I like this guy. There is always value in learning.