Thank you for your support even without having a Pi3.
I think that PIN 13, wiringpi pin 2 is the pin which lets the power flow into the Pi. It is always high, even if the board is switched off.
When I switch the board on, with the battery connected, then physical pin 1, 17 are high (which is correct as those are the 3.3v pins) AND pin 13 is high as well.
I have not written any script yet - I would like to write a script, however, I first need to identity that the BATT_OK and AC_OK pins have voltage. At the moment only physical pin 13, wiringpi pin 2, has 3.3v, I cannot identify the BATT_OK pin - both pins right next to 13 according to the UPS3 schematics should provide high voltage when turned on, but they are both on 0 when measuring with DMM, why?
According to Odroid specification the pins are exactly the same for Odroid C2 and Pi3, except for 3 pins.
And here is the matching schema for Pi3 and wiringpi pin is 0 and 2 - like on odroid.http://raspberrypihobbyist.blogspot.com ... agram.html
Do I need to set the AC and BATT pin somehow to enable a voltage measure?
I want to identify the right pin to know that the battery is still strong enough, before triggering a safe shut down