SNLS614A September 2018 – December 2018 DP83869HM
The DP83869HM supports the Parallel Detection function as defined in the IEEE 802.3 specification. Parallel Detection requires the 10/100-Mbps receivers to monitor the receive signal and report link status to the Auto-Negotiation function. Auto-Negotiation uses this information to configure the correct technology in the event that the Link Partner does not support Auto-Negotiation, yet is transmitting link signals that the 10BASE-Te or 100BASE-X PMA recognize as valid link signals.
If the DP83869HM completes Auto-Negotiation as a result of Parallel Detection without Next Page operation, bits 5 and 7 of ANLPAR (register address 0x0005) are set to reflect the mode of operation present in the Link Partner. Note that bits 4:0 of the ANLPAR are also set to 00001 based on a successful parallel detection to indicate a valid 802.3 selector field. Software may determine that the negotiation is completed through Parallel Detection by reading 0 in bit 0 of ANER (register address 0x006) after Auto-Negotiation Complete—bit 5 of BMSR (register address 0x0001)—is set. If the PHY is configured for parallel detect mode and any condition other than a good link occurs, the parallel detect fault—bit 4 of ANER (register address 0x06)—sets.