> However, as far as your question goes- I believe the impedance of a pin on the
> PIC is high enough that you could hook 8 largish caps up to eight pins, and
> charge or discharge them before turning the PIC off.  Run some tests, and report
> your results.
>
> I would probably charge them, then turn the pins to input before powering off
> (just in case the chip decides to power itself from those caps that are charged,
> and still connected to output high)
>
> -Adam

I don't think this would work. When Vcc drops the internal
protection diodes on the port pins will begin to conduct, feeding
power from the caps back into the power supply.

Probably you could make it work with some smart circuit using a
diode or two and a MOSFET. Do you need 1 byte or 1 bit?
EEPROM may be the best bet, could you drop in a PIC16F84?

Brent Brown
Electronic Design Solutions
16 English Street
Hamilton, New Zealand
Ph/fax: +64 7 849 0069
Mobile/text: 025 334 069
eMail:  brent.brown@clear.net.nz

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