This could be a can of worms.
Try "PC Intern", by Michael Tischer, ISBN 1-55755-145-6, C.1994.
It is old (and 1300 pages!) and focuses on DOS system programming, but his
chapter 5 is on PC keyboard handling. Maybe you can borrow a copy.
Extracts from his book: Keyboards generate a scan code for each key, or
combination of keys, pressed.
The transfer to the PC is synchronous.
Keyboards use(d) the Intel 8042 chip to read the switch presses and generate
the scan code. Complicated stuff, this.
Good luck with this one.
ATH

At 09:03 PM 11/10/98 +0100, you wrote:
>Hi!
>
>I need a secound keyboard for a self written program. I want to insert it
>between the PC and a normal keyboard. Does anyone know how the transfer
>between PC and keyboard is working? I want to use a 16C84 PIC for the
>keyboard controller? Can you help me?
>
>Peter
>
>
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Andrew Hitt
Raytheon
805-355-1710
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