> Done. There are eight button cells, about 3mm tall and 9.5 in

Way to go. Here are some tips from Microchip. The nW parts
are what you really want to be using for longest battery life (I've
tested the 12F675 at 7nA SLEEP current)

================================

http://www.microchip.com/stellent/stellent/idcplg?IdcService=SS_GET_PAGE&nod
eId=1484

Q. How can I make my PIC16/17 run as low power as possible?

A. Section Tips Posted: 10/25/1997 10:35:49 AM Discussion:

1. Run the clock as slow as you can.

2. Disable the watchdog timer

3. Put the part to sleep whenever possible.

4. Use MCLR to wake part from sleep instead of the WDT if possible.

5. Do not let any inputs float.

6. Do not drive any unnecessary loads. Minimize capacitive or inductive
loads on switching I/O pins, or resistive loads on other driven pins. If
a pin is not to be used you can leave it disconnected and drive it low
or high, or put a pull up or down resistor on it as an input.

7. Turn off all timers when not in use. For instance, TMR0 can be
incremented from the instruction clock or an external pin. When not in
use, assign it to the pin (if it is toggling at a lower rate than the
instruction clock). Do not use prescalers when unnecessary. In other
words, minimize the amount of logic changing states.

8. Turn off any other peripherals when not in use

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