TomWS:
In my experience with ARM processors, an unconfigured pin is literally an 'un-connected' state, not 'high impedance'. This is much lower power than configuring it as an input and leaving it floating.I don't recall if configuring as an OUTPUT (assuming it is truly unused) is similar low power to an unconnected pin. However, I am sure that unconnected is the absolute lowest power.
Tom
Hi guys,
@Tom, I also came across this in the SAMD21 manual, which states: "39.6 Unused or Unconnected Pins
For unused pins the default state of the pins for the will give the lowest current leakage. There is thus no
need to do any configuration of the unused pins in order to lower the power consumption."
@androidfanboy I also used the Moteino M0 board with my Adafruit Feather Adalogger M0 and was able to get down from ~360 uA to 80 uA! Not bad! I also posted on Felix's forums and he said that the difference is basically his definition lacks some input initializations.
The reduced quiescent draw is great, but are there any disadvantages to using the Moteino M0 board definitions with Adafruit Feather boards?
Cheers,
Adam