I'm trying to identify this port and read data off it. It's 1cm across, including a small square on the lower left. 3 pins, leftmost near square seems to be GND and rightmost reads 3.3V+ w. respect to leftmost pin.
It's an unlabelled port on an unbranded watt meter, I haven't found any markings or writing when opening the case, there's no manual/specs, and I'd rather not disassemble the internals in hopes of finding out.
I'm assuming I can interface with this with an Arduino, but I don't know where to start. Any identifications or tips on how to communicate with it will be appreciated.