8 hours is a long time to expect a cap to hold it's charge. Also, when the
PIC supply drops there will be a discharge path through the input
protection diodes.
How about a latching relay? They only draw power when changing state - but
cost more than a simple cap. Or a simple implementation of the old style
magnetic core memory - probably not too simple on reflection. You might
find a small EEPROM implementation the best solution.




I am using 16c505 pic 14 pin
Could any one offer me any trick for making a memory when power is off for
8
hours
I was thinking if I could charge a cap before power of
when power back on I could check status of pin
thank you
Bruce Stephens

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