> my main question is Can I use PIC's hardware SPI interface for keyboard or
> mouse. I like PIC18F parts. any info will appreciate.

It would be a waste of a good SPI interface... The keyboard/mouse
interface runs at an incredibly low clock speed (rarely faster than
1200 bps). It is very simple to attach the clock to an interrupt on
change enabled pin, and just shift the bits into a register as they
come in. The big advantage of the PS/2 interface is that the keyboard
and mouse generate their own clock, so you don't really need to do any
clock stuff on the PIC itself...

Greetings,
Maarten Hofman.

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