This is pretty cool! The presentation was ... long, but I still failed to find some details I would have appreciated, just to get a better idea of what it does.

This is pretty cool! The presentation was ... long, but I still failed to find some details I would have appreciated, just to get a better idea of what it does. It's clear that it physically houses various wireless modules, but how does the connection "up" to the RPi work? I thought the RPi had pretty few I/O pins, so there must be some sort of multiplexing going on, I guess? The presence of pure I2C components such as the thermometer and real-time clock hints that the hub talks to the RPi using I2C, but it would be nice to have some kind of schematic showing how it all fits together.