Core Ink: recognize if USB or battery powered

  • Hello,

    I bought the Core Ink for quick prototyping. I am very satisfied with the quality and the possibilities. What I'm missing: How can I tell if the device is USB or battery powered?
    My firmware should provide an access point with a web interface, but only if the device is not running on battery power.

    Current idea: I could use the battery voltage trend to determine whether the battery is charging or discharging. For this I have to check how accurate the internal measurement is. In any case, this implementation would be very cumbersome.

    Maybe there are simpler options?

  • Please search the forum as this has been discussed and possible solutions created by users.

  • @ajb2k3
    Thanks for the hint. Found a 3 years old thread. It is not possible to detect if it is powered from USB or battery...

  • I checked again electronic circuit:
    It is possible to take some measurements on HAT interface's pin "5VIN". Measured voltages:

    If powered by USB:

    Powered by battery and switched off:

    Powered by battery and switched on:

    Using voltage divider with two same resistors, we get usable logic values for HIGH and LOW ( ~2.3V and ~1.2V). The measured values are not inside garanteed logic range but as a workaround: it works well.

    Maybe it helps someone else...

  • @davincino Thanks for posting your findings.