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USB Keyboard hack question
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Lilwolf:
its not a keyboard hack good / bad question.. .but specifically USB

the trouble with the USB keyboard hacks is the USB keyboard spec specifically says 6 keys.  So most keyboards will implement it specifically for 6 keys.  You might get a few more depending on the keyboard... but since no ghosting is specifically more expensive, most don't.

There are other hotswappable control panel options.  I went with building my own tac switches that connect with standard barrier strips (something like these Radio Shack Link So the expensive parts where in the cabinet... but each control panel had a small 2 dollar barrier switch with easy wiring built in.

But after all that work, it wasn't all that bad plugging in the 2 db25 serial cables... and that was MUCH cheaper (buy M-M 25pin serial cables on ebay in bulk and cut them in 1/2 for the control panels.  Again a few bucks each)
cmonkey:
I think you were correct in assuming that the limit is per keyboard, and not system-wide.  However, I've never tried it myself.  Anyway, failing that, another plan would be using RJ45 (ethernet) plugs and jacks to make it modular and just having the encoder in the cabinet.  You could hook up 7 buttons per plug.

Peale, I'm using a PS/2 keyboard hack for a 4 player CP.  I'm fairly certain I have a matrix set up that will work with no ghosting, blocking, or key-limit problems.
Izrun:
Yeah, I know plugging and unplugging things is not really a big deal.  However, once of my main goals is for my wife or any of my friends to be able (and willing) to swap out components with no knowledge of what to plug in where.  I'm planning on doing some sort of contact usb connection.  Again, I'm still in early planning and am just collecting some components (I figured I would put a message in project announcements once I get a little more focused).  On ebay today I scored a full Spy Hunter control panel for 20 bucks shipped (eBa y Link) and a pair of steel gunner 2 guns for 20 bucks (eBay Link 2), so I'm pretty excited. 

My other thought is to use a bunch of hacked gamepads.  I would then write an app that would detect which location each unit was plugged in and map them accordingly. 
Izrun:
Oh, I realized that you were talking about something similar to what I was talking about.   That is similar to what I was thinking.
hanelyp:

--- Quote from: Lilwolf on June 23, 2006, 07:05:32 pm ---its not a keyboard hack good / bad question.. .but specifically USB

the trouble with the USB keyboard hacks is the USB keyboard spec specifically says 6 keys.
--- End quote ---
To be specific, the USB boot keyboard standard (which practically all USB keyboards follow) allows 6 general keys + any combination of shift, control, alt, and 'system' keys.  In the pannel I'm planning, control and shift are being used for 2 of the trigger buttons, pushing the limit to stick + 6 buttons.

Using all control, alt, and shift keys, I could get 12 closed switches at once, at the risk of some software not supporting all the buttons.  Also, the extra 6 would be a 1 keyboard thing.

The more general USB HID standard is far more flexable.  A game encoder intended to be read as a keyboard would have no difficulty with 64 switches.  It just wouldn't work as a 'boot' keyboard.
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