Mod for multi-common ground/line controller

Tech Talk
1

So after doing some digging, I came across bencao’s fantastic guide on hooking up a common ground joystick to a non common ground pad. I did some searching, and found out opto couplers are kinda expensive, and I can only source 6 pin ones, which means I’d have to use stacks for a full pad conversion. =[
Looking around bencao’s blog, turns out he put forward an alternative, with more parts but cheaper. After bugging him and having my (probably dumb) questions answered, I spent some time cooking this up.

http://members.optusnet.com.au/kitatchung/shoryuken/rendersmall.gif
(the ‘k’ before the numbers in the bottom ICs is for 'Key" or Legend. They are for reference. Click for larger version)

I was wondering if anyone could take a look, and let me know if this would work. Spent a bit of time on this (about 4 hours, plus about 1h40mcleaning up my mess). In hind sight, I should have labeled ‘PCB XX’ as ‘Pad XX’, but after realising halfway through, I really CBS going back to change it. It’d take another hour and a half.

Which reminds me, does anyone have a good recommendation for circuit programs other than DIY Layout Creator? It’s gotta be one of the laggiest programs I’ve used in ages. I don’t want to wait five seconds everytime I click something.

Edit: Ah, I guess I should mention that I’m converting an early X360 wired pad here. I’m hooking up LB and RB, and leaving the triggers. While I have the Xbox Guide button in the circuit, it’s mainly for posterity’s sake, as I won’t be hooking it up. If this circuit is viable, I’m sure it’d be useful to someone else. =]

2

Hi,

thanks for the props. I was inspired by Toodles doing the alternate cg mod. It’s quite difficult to trace down the wiring, so this will take a little time.

But I reccommend Eagle for drawing schematics. I was using this scrappy Tool for prototyping, but as you say, it lags and lags and lags.

But I think you get it…

3

I agree with ben, Eagle is the way to go. He showed me the light!

And because of his work, I too did some researching and found a cheaper method without using any chips. I made a common ground converter for sixaxis controllers using only pnp transistors and resistors.

4

My goodness, I just realised I spelt your name wrong bencao! -_-
So sorry, was getting tired just before I posted. It’s been fixed in the post, I’ll get around to fixing it in the image soon.

5

I was taking a look at the parts, and it seems there’s a 74HC4066, and a plain old 4066. Both are Quadruple Bilateral switches, so I was wondering what the difference is? the regular 4066 costs about 1/3 of the 74HC4066, so I was wondering if it was possible to substitute that instead?