More information on the 1000BASE-X PCS registers can be found in clause 22 and clause 37 of the IEEE 802.3-2008 specification. Registers at undefined addresses are read-only and return 0s. The core can be reset three ways: reset, DCM_LOCKED and soft reset. All of these methods reset all the registers to the default values. For 2500BASE-X, the register definition is same as 1000BASE-X.
| Register Address | Register Name |
|---|---|
| 0 | Register 0: Control Register |
| 1 | Register 1: Status Register |
| 2,3 | Registers 2 and 3: PHY Identifiers |
| 4 | Register 4: Auto-Negotiation Advertisement |
| 5 | Register 5: Auto-Negotiation Link Partner Base |
| 6 | Register 6: Auto-Negotiation Expansion |
| 7 | Register 7: Auto-Negotiation Next Page Transmit |
| 8 | Register 8: Auto-Negotiation Next Page Receive |
| 15 | Register 15: Extended Status |
| 16 | Register 16: Vendor-Specific Auto-Negotiation Interrupt Control |
Note: In the following register definitions, R/W is
Read/Write, RO is Read Only.