The board takes power and data from PoE-enabled switch. The power is routed to the board where DC/DC module converts it down to 5 volts, while data is passed through transformer to the other Ethernet Jack. A short patch cable is used to connect the shield and Raspberry Pi, Raspberry Pi's own PHY handles the Ethernet communication.
No software setup is needed for the board, board handles the PoE negation automatically and powers the Raspberry Pi through the pin header's 5V connection.
This is not a proper HAT for two reasons:
- the board is longer and Ethernet connectors are directly above Raspberry Pi's USB and Ethernet connectors
- there is no EPROM and we have long pinned connector so that you can plug a proper HAT on top of your Raspberry Pi