Well this was a fun discovery.

Let's see how many of you get this right.

If you read MDIO address 0x0 of a gigabit Ethernet PHY and read the values in bits 13/6 and 8 (speed and duplex state), do you get:

1) The last value you wrote to the register, regardless of actual link conditions

2) The actual current speed/duplex state the PHY is operating in

3) Something else / undefined