1 Reply Latest reply on Aug 24, 2015 2:42 PM by PabloM_Intel

    Edison Mini Breakout, connect Battery to RTC

    MinorFixes

      Hey there,

       

      I'm trying to connect a coin battery (3V) to the built-in RTC of the Intel Edison, so it keeps the time even when the board gets disconnected from a power supply for hours. The battery is similar to the one recommended in https://communities.intel.com/message/298632.

      I'm using the Mini Breakout board and according to the Hardware Guide for it, V_VBAT_BKUP is on J18 - Pin 5. As suggested in https://communities.intel.com/message/256947, I connected the + pole of the battery to the pin.

      The board is running ubilinux. Setting and reading the RTC using hwclock works fine, if I use the --directisa flag. However the RTC gets reset if I poweroff the board and restart it.

      The battery is new and I verified that it's still full.

       

      Here's the content of /proc/driver/rtc

      root@warehouse-edison:~# cat /proc/driver/rtc

      rtc_time        : 15:40:00

      rtc_date        : 2015-08-24

      alrm_time       : 00:00:16

      alrm_date       : 2000-01-02

      alarm_IRQ       : no

      alrm_pending    : no

      update IRQ enabled      : no

      periodic IRQ enabled    : no

      periodic IRQ frequency  : 1024

      max user IRQ frequency  : 64

      24hr            : yes

      periodic_IRQ    : no

      update_IRQ      : no

      HPET_emulated   : no

      BCD             : yes

      DST_enable      : no

      periodic_freq   : 1024

      batt_status     : okay

       

      What am I missing? I appreciate any help.

      Thanks!

        • 1. Re: Edison Mini Breakout, connect Battery to RTC
          PabloM_Intel

          Hi MinorFixes,

           

          Have you tried this same connection using the regular Yocto image instead of Ubilinux? Most tests with RTC have been made using the Yocto image, so I would suggest you to try it. If what you want to do is to power the Breakout Board with a rechargeable battery, you can also do that via J2. The battery will be recharge every time the board is supplied via J21 or J22.

           

          Regards,

          PabloM_Intel