Comments on: Keybot – serial controllable keyboard interface

By: derek

derek — Mon, 05 Mar 2007 07:35:10 +0000

Cool. This reminds me of something similar, where a board with five switches rests at my feet. An arduino usb monitors and reports back to software the activities of the buttons, for doing various things - http://dmgaming.com/switchboard - it's also nice bringing music controls outside the computer.

Windows XP has a feature called "serialkeys" which turns serial data into keystrokes, this is useful for using a microcontroller / external switches to play FPS games.

By: lain

lain — Wed, 21 Feb 2007 17:18:18 +0000

over-engineered.

By: azoore

azoore — Tue, 20 Feb 2007 02:44:38 +0000

Nice implementation. I made something similar a while back using a USB PIC. The keystrokes are programmable through USB and stored in an external EEPROM. Delays can also be added to simulate real-time typing.

http://www.azoore.net/usbkbemu.html

By: kyle

kyle — Tue, 20 Feb 2007 00:57:01 +0000

@6: you probably want something like a quine:

“In computing, a quine is a program (a form of metaprogram) that produces its complete source code as its only output”

By: Alex McCown

Alex McCown — Mon, 19 Feb 2007 23:57:57 +0000

USE transistors dumb ass

By: sqnewton

sqnewton — Mon, 19 Feb 2007 21:49:33 +0000

One little detail: the ’snubber’ diodes connected to the relays on the schematic diagram are reversed. The Cathode should be connected to the positive side and the anode to the transistor/darlington. Nice work!

By: Jozer

Jozer — Mon, 19 Feb 2007 21:46:28 +0000

Brings up the question:
Can you write a program that will type itself in and compile itself without reference to its source code files?

By: Luke

Luke — Mon, 19 Feb 2007 20:50:15 +0000

So, you definitely did this the hard way… The REALLY hard way.

If anyone else considers doing this, the easy way would be to buy one of any number of microcontroller demo boards that has both a USB and serial port.

And relays? Seriously? Come on, dude, you can do better than that. :)

By: tyler

tyler — Mon, 19 Feb 2007 19:20:31 +0000

hmmm, this seems really interesting, as just a few months ago I was requested to rig a game to pause after 30 seconds, then restart. I thought about a micro sitting on the ps/2 line, but I wasn’t sure how hard that would be to create a passthrough.
I ended up just soldering to the keyboard’s controller, as it only needed to press 3 buttons – esc, right, enter.
I used some small reed-relays connected to the parallel port.

Maybe if my client wants it redone, i’ll look into using a microcontroller.

By: ex-parrot

ex-parrot — Mon, 19 Feb 2007 13:31:21 +0000

I agree. While this has a Rube Goldberg-esque charm, I think a more elegant solution would be to simply implement the (widely documented) PS/2 protocol on a microcontroller.

By: Alex B

Alex B — Mon, 19 Feb 2007 12:44:57 +0000

One might trade hardware complexity for firmware and use a microcontroller instead. It could interface directly with the PS/2 port and emulate a keyboard.

By: Alex McCown

Alex McCown — Mon, 19 Feb 2007 08:34:07 +0000

i made something like this awhile back but i used transistors instead of relays i used it to have a computer play css on the other comp ( it dident work out lol)

By: morcheeba

morcheeba — Mon, 19 Feb 2007 08:19:51 +0000

I remember back in the day, there was a product that you’d put over your electric typewriter and it would turn it in to a printer. It was like this except that instead of making electrical connections, it actually used 40-odd solenoids to depress the individual keys!