usb keyboard hack. a couple of questions

[saxon]

hi. i am making a few 4-way arcade sticks for friends mainly to play mr do! (as well as some other 4-way classics)
i have decided to use hacked usb keyboards for the controls. the reason is i only want 5 inputs (up,dwn,rght,lft and fire) and i can map them to mames default keys so their is no setup needed just start the game and their away.. i also got 5 usb keyboards for £5 so thats only a pound each to add to the cost of the stick.

i just wandered if someone could help with these questions.

1. their is an earth wire that comes from the keyboard usb cable. On the keyboard it connects to a metal plate behind the button matrix. what should i do with it on my joystick, my cases are made from plastic but i could solder it to the metal plate on the back of the joystick? or should i cut it off or any other ideas.

2. the usb lead on the keyboard is a bit short. if needed would it be ok to use a usb extension cable cut the unwanted end off and solder the 5 coloured wires to the encoder.

thanks for any help

mike.

[steveh]

In theory you can just cut a longer usb and solder it in place, but its probably just easier to use a  premade extension. 

as for your first question, maybe you can provide some pictures?

[saxon]

Hi. Many thanks for the reply

I have included a couple of pictures

The first shows the encoder still on the keyboard with the earth (well i think its an earth) wire attached to a metal plate that is at the back of the keyboard behind the film matrix

Picture 2 is the back of my joystick (its a slightly different encoder but as the same wire coming from the usb cable) its all connected and working great but not sure what to do with the earth wire shown.

It works fine without it connected but I just want to be safe and not blow any of my friends pc's up

Cheers Mike

[Nephasth]

If you're really worried about it, just run it to a joystick mounting hole.

[MTPPC]

I hope your experience with that zippy joystick is better than mine. I had a micro switch that would just fail to register about every 500th time. It was very frustrating to play with and I ended up going back to the joystick that came with the game.

[saxon]

The zippyy stick is a bit cheap and nasty and I certainly wouldnt recommend it for a cabinet but with a few little modifications it works great as a 4-way / 2-way stick. and I found it good enough to smash my Mr Do! Highscore to close to 2 million. I have not yet had any microswitch failures.

Regarding the earth wire is it best to solder it to the joystick mounting hole? as I said it works fine with or without it connected. I am not worried about it its just as I do not understand electronics I wanted to be safe. Its connected to the a metal plate on the keyboard for a reason so I just wandered if its best to connect it to the joystick mounting plate.