Messages in this thread | | | Date | Wed, 13 Aug 1997 08:43:18 -0400 (EDT) | From | "Richard B. Johnson" <> | Subject | Re: Keyboard error |
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On 13 Aug 1997, Matthias Urlichs wrote:
> hpa@transmeta.com (H. Peter Anvin) writes: > > > > The annoying part of all of this is that this could easily be reduced > > to a non-issue if keyboard manufacturers would only put a diode in > > series with each keyswitch... > > > What, 111 diodes? At $0.01 each? > > Nah, that'll kill the profit margin.
Scarry. You can't rely on diodes anymore. They require a connection that will carry some current. Many keyboards now use a change in capacity to detect if a key bas been struck. This allows a wiring pattern to be painted on (no printed circuit with co$tly metal). The keyboard uP is emulated also. US$1.01 in hardware, a million is software... but software is free <grin>.
Cheers, DJ Richard B. Johnson Analogic Corporation Penguin : Linux version 2.1.44 on an i586 machine (66.15 BogoMips). Warning : It's hard to stay on the trailing edge of technology. Linux : Engineering tool Windows : Typewriter
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