Quote Originally Posted by Archangel View Post
You isolate the PIC power from the power supply with a diode. Place a large cap on the PIC side of that diode to power the PIC when the power fails, and interrupt the PIC & write the eeprom when power failure is sensed on the other side of the diode. Very possible. HTH
Yes, thank you. For some reason I assumed the OP was suggesting that the PIC would be without power - in such a case writing to EEprom is clearly impossible. A battery or capacitor is an ideal solution - providing power AFTER the main is switched off. Yours (and others?) suggestions to provide power via a cap is a very efficient answer - allowing, with careful design - the ability to control the shutdown and perhaps even position the servo in a non-destructive position before exhausting the supply. Thanks again!