SNLU289 September 2020 DP83TG720R-Q1 , DP83TG720S-Q1
Open the USB2MDIO tool and under Settings select Baud Rate = 9600 plus the COM Port of the desired USB Port.
The correct USB Port can be found in the Device Manager under Ports (COM & LTP) :
After that press Open Port.
Now either File à Find PHY ID is available or if already known, the PHY ID can be directly selected from the drop-down menu.
The PHY-ID of the DP83867867 PHY is 0x00.
The PHY-ID of DP83TG720 PHY is 0x08.
Now enter the register to read or write a value.