4:00 pm, it's always 4pm. To be specific it's New Year's Eve 2015 and my Pine thinks it's enjoying the good life on the beautiful west coast of the US.
So, my question to the Pine dev team, Can I add a battery backup clock to my board thru the GPIO pins? Like this one I use on my Arduino projects:http://www.ebay.com/itm/2X-DS3231-AT24C32-IIC-precision-Real-time-clock-RTC-memory-module-For-Arduino-/221972261503?hash=item33ae93ea7f:g:QGoAAOSwZ1lWdDWW
Well color me stupid. I didn't know realize that was what RTC stood for. I guess it would have been funnier if it was an April Fools joke instead of me missing the obvious.
Thnx
04-03-2016, 11:03 AM
(This post was last modified: 04-03-2016, 11:04 AM by MichaelMeissner.)
Even if you don't power the real time clock to keep the time across power cycling, if your pine64 is connected to the internet, just run ntp to sync the system clock with internet time every so often.
Now, if you plan to run the pine64 without internet, then yes you want to provide power to the RTC port. I have not seen whether the developers have added the smarts to monitor the temp and auto correct the time. I would suspect that they use the built-in RTC in the arm chip with a decent crystal (but not super expensive one), it may drift a little bit. The DS3231 chip in various i2c RTCs (like Adafruit's Chronodot) does this and provides a more accurate time source. I would suspect that when internet is available you should run ntp, and every so often reset the hardware clock to internet time.
Alternatively, if your pine64 is running outdoors, consider getting a GPS and hook it up to one of the pine64's serial UARTs. As part of the GPS infrastructure, it provides accurate time.
It all depends on how accurate you need the clock to be.
Also consider fake-hwclock as it saves the last known date, so logs dont start at epoch 0.
