On Sat, 25 Jul 1998 12:34:34 -0400, you wrote:

>For the sake of newcomers to the PIC, I offer a few ideas.
>
>Sometimes I notice people trying to use a single PIC to do
>everything, and eventually ending up with lots of extra
>peripheral chips such as shift registers hanging off of
>the PIC to implement the extended I/O. I do this myself,
>when the I/O load is low and the programming load on the
>PIC is reasonable.
>
>But sometimes I find it easier to simply use one or two
>serial lines and communicate my extended I/O needs to
>another PIC.
>
>I often 'steal' my clock from the master PIC. That also
>guarantees that both PICs are running the same speed.
The 12Cxx series are especially good for this - no need for any clock
distribution, cheap and small. The A/D versions (67X) can be used as a
complete 'smart' analog acquisition subsystem - sensor power control,
calibration, input change detection etc. etc. 
     ____                                                           ____
   _/ L_/  Mike Harrison / White Wing Logic / wwl@netcomuk.co.uk  _/ L_/
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