Charles J Knight wrote: > > > > The only thing that springs to mind, is the "credit card" > > organizers > > > that have calculator key type buttons. There are a few that have > > > > I like it. I can't beleive I never thought of that...especially when > > I have a organizer which would just be perfect for the job. For the > > Personally, I would prefer *real* keys with keyswitches in them, but > let's keep this simple. Why reinvent the wheel? > > I picked up a tiny organizer, myself, a while back. I love Goodwill > stores -- $.80 for a working unit! Now, it's just a matter of hacking > it. > > > For wiring I'll stick to using the already attached cable for now. > > For the time being I Don't really mind another cable, but I will > > Hey, a standard PS/2 connector is a BIG plus with this stuff. It > lets you test setups, etc, with regular equipment. Far fewer > variables to worry about. > > -- Chuck Knight How large a keyboard are you guys thinking of, for the finished units, if you want to go PS/2? PS/2, BTW, isn't really an RS-232 protocol (there are 2 shared data lines, loosely pulled up at each end; Each end pulls the lines down to communicate, in the prescribed method. One line's data - the other's clock. It takes "smarts" to do this, some kind of microcontroller. If you can find an existing keyboard controller card & just swap the tiny keyboard's wires in; that's fast. I'm investigating potting materials, I suspect I could probably make, or teach someone else to make, custom key caps for this sort of thing in small batches, shortly. (Think, paste a letter to the "top" of each keycap with epoxy, then pot the rest of the cap - set the whole "plate" in a small centrifuge to remove bubbles - Grind the keys to uniform height; That sort of thing. Clear epoxy resins probably would do. Those who touch type wouldn't need the key caps, those'd be cheaper. Lot of hand work to do there!) You can buy good keyboard switches that're as small as 8mm square, water tight, for 48 cents apiece; under half that in quantity 1000. And 6.3mm SMT tactile switches for 18 cents apiece, if you get 3000 at a shot. That'd mean a 104-key keyboard could be as small as 5.5 inches wide by 2.25 inches tall or so... Drop to a 4.5mm square keyswitch which doesn't have a "top", about the same pricing, and you get a 4.125 wide x 1.6 inch keyboard. There are 3.7mm x 6mm rectangular switches, too. Not your usual "aspect ratio" of the keyboard, though. Except, I think I see how to make these fit in about a 4mm x 4mm grid. Maybe a little smaller. I'll get out some paper & do a sketch later & see how it'd work. Suggestion: use some sort of ESD protection on this keyboard <G> (A metal front plate would do, have it grounded through a 1Meg resistor, etc.) Mark -- I re-ship for small US & overseas businesses, world-wide. (For private individuals at cost; ask.) -- Subcription/unsubscription/info requests: send e-mail with subject of "subscribe", "unsubscribe", or "info" toWear-Hard Mailing List Archive (searchable): http://wearables.blu.org
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