Keyboard Hack wiring almost complete...

[riley454]

I've mapped the matrix of a USB keyboard pcb and can't see any possible ghosting issues. I've accepted the possible limitations of a USB keyboard to a max of 6 simultaneous inputs and I don't think this is an issue for my 2 player control panel and the games I'm likely to play. Most of the wiring has been soldered to the PCB which will be connected to a wiring block then eventually to my buttons and joysticks.

I need some advice on this...
There is a black wire with a connector on its end coming from the same point as the USB cable earth connections on the PCB and another black cable from the other end of the board independent of the USB wiring. My logical assumption is they are earth wires used in the former keyboard, but do I need to connect them to anything in my control panel? I wasn't planning to, because all the keystrokes worked by connecting the wires from my matrix and with nothing touching these earth wires. It occurred to me that maybe I might have to earth the board somewhere. Is this necessary to protect my computer or anything else from damage?

[Ed_McCarron]

Probably not.  If its what I think it was, it was just to pass FCC emission regulations by grounding the inside of the keyboard case - with either metal shielding or spray on conductive stuff.

[BobA]

Usb cable are shielded and supposed to only be terminated at one end or as Ed says probably part of the keyboard shielding.

[riley454]

Ok thanks. I'll just insulate the ends and leave them dangling.