3 Replies Latest reply on Dec 20, 2015 10:46 AM by jp49miller

    Galileo rtc wake-up possibilities ?


      I read in the Quark Datasheet:

      "The RTC supports a date alarm that allows for scheduling a wake up event up to 30 days in advance."


      Can you really wake up the Galileo using the date alarm ? I will look for an answer for sure, but how can you do that ? Thanks !

        • 1. Re: Galileo rtc wake-up possibilities ?

          Just to add to the question - wakeup implies a sleep. How do you put the chip into a low current sleep state? Is wakeup a reboot, or continue from where you were? What is current drain while asleep?

          • 2. Re: Galileo rtc wake-up possibilities ?

            I keep time with a 3.3v coin battery on board battery connector. Set time for software and then sync clock to hardware. For safety and convenience, I keep it on a holder plugged in a very small blue breadboard and blue/white male-female jumper wires... Adds to the look. PS: I don't really exactly know know about the current draw when asleep, but since the end of December, it keeps the time .

            • 3. Re: Galileo rtc wake-up possibilities ?

              Most coin cells have a capacity somewhere in the range of 250 mA-Hours.  The maximum drain of the Quark by RTC is 6 uA.  0.25/0.000006 is 4.7 years.  The coin cell at room temperature should last at least that long - probably much longer.


              I put a 0.22 F super-cap with a resistor and diode from 3.3 on mine.  It should last about 12 hours and charge back up in a couple.   It covers power outages and moving the board.

              1 of 1 people found this helpful