Hi Randie (Randie Ohtsji [4555]), in
 <199710242027.NAA15965@glenvan.glenayre.com> on Oct 24 you wrote:

> Still undecided.  I really like the I2C method but the only thing
> holding me back is that none of my devices have the I2C feature
> (including the micro......I want to use the PIC16F84 because of
> re-programmability).  I like it because future addons don't require
> a complete re-think of the structure, but they can be plugged in
> as a daughter board or external upgrade module (same thing really,
> just different marketing terms)

You can use an AT89C52.  It has 32 IO pins and 8K of internal FLASH program
memory.  It's 2x the price of an F84, though.