Go Down

Topic: Circuit which powers Arduino long enough to save program state to memory (Read 2 times) previous topic - next topic

RuggedCircuits

Quote
The provided example uses a 0.47F capacitor. In what price range is that?


Strongly depends on the voltage, but in the 5V and less domain the prices are quite reasonable, for example:

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=604-1002-ND

Quote
The provided code shows that the voltage monitoring must run continously in the main loop. Is there no interrupt/event implementation within Arduino. (Sorry if my question is naive, I am a newbie)


Sure, if you want to dedicate an I/O pin for voltage monitoring you can just run the external power supply there through a diode and a voltage divider (diode so the hold-up voltage from the supercap doesn't get to it). The provided code is really about doing a "no hardware" approach to power failure detection.

--
Beat707: MIDI drum machine / sequencer / groove-box for Arduino

Go Up