adwsystems:
The Mini power input is 7-9V. How are you connecting it to the Feather to get a voltage in that range?Sure why not? There's an example around here on connecting to Arduinos via I2C.
It says here that the input power is 3.35-12v, so I guess the Feather's 3.3v is not enough. I thought a 3.3v system could power another 3.3v system. Do you know if it will work if I step up the voltage?
Blade2021:
Personally I think it would be more feasible to use their data logging feather if you have the available pins. Merely just a suggestion. I have a couple of feathers myself and love that they all layer with ease.
As adwsystems says, I don't think it will change my program space, as I still need the same libraries as now.