[geeks] peecee keybaord interfaces?

[Jochen Kunz]

On Tue, 24 Feb 2009 13:06:25 -0500 (EST)
der Mouse <mouse at Rodents-Montreal.ORG> wrote:

> it clearly isn't the simple serial thing I'd
> expect, or there'd be two data lines and no clock lines.
There is a data and a clock line, open collector with pull up
resistors on the PeeCee side, both bidirectional. (Plus the obvious +5
V and GND, other pins are unused.) It is a simple sync serial protocol:
Start bit, 8 data bits, parity bit, stop bit. I hacked some code to use
a PS/2 keyboard as an input device for Atmel AVR microcontolers a while
back...

Have a look at:
http://www.beyondlogic.org/keyboard/keybrd.htm

The question is how the barcode scanner interposes the signals.

An other solution: Connect the keyboard to the PS/2 port of the PeeCee.
Get a PS/2 keyboard / mouse to USB converter. These things turn a PS/2
keyboard (and mouse) into a USB keyboard (and mouse). Then connect the
barcode scanner via USB. This makes hot pluging easy. A modern
operating system should be able to handle two keyboards. At least
NetBSD is perfectely fine with this.
--


tsch|_,
       Jochen

Homepage: http://www.unixag-kl.fh-kl.de/~jkunz/