BECKHOFF EtherCAT Registers Section II - Manual (Page 62)

MII Management Interface (0x0510:0x0515)
II-50 Slave Controller – Register Description
3.46 MII Management Interface (0x0510:0x0515)
Table 70: MII Management Interface Register Overview
Register Address Length
(Byte)
Description
0x0510:0x0511 2 MII Management Control/Status
0x0512 1 PHY Address
0x0513 1 PHY Register Address
0x0514:0x0515 2 PHY Data
0x0516 1 MII Management ECAT Access State
0x0517 1 MII Management PDI Access State
0x0518:0x051B 4 PHY Port Status
PDI controls the MII management interface if MII Management PDI Access register 0x0517.0=1, otherwise
EtherCAT controls the MII management interface. Exception for ET1100: PDI controls the MII management
interface if Transparent Mode is enabled.