I wrote:
>
>The PIC internal timer makes a fine RTC, if the xtal frequency is
>chosen correctly [some power of 2], and as long as updating the clock
>and data acquisition don't louse up each other's timing.
....

BTW, more correctly I should have said the xtal can be chosen as an
*integer multiple* of a power of 2. For instance, 4,915,200 is a std
xtal frequency, and is 75*256*256. Here, timer T0 could be set to
interrupt after reaching max count, and a s.w. variable would count
down 75 times ---> 1 sec.

best regards,
- Dan Michaels
Oricom Technologies
http://www.sni.net/~oricom
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