SNLS614A September 2018 – December 2018 DP83869HM
If a link is established by successful Auto-Negotiation and then lost, the Auto-Negotiation process resumes to determine the configuration for the link. This function ensures that a link can be re-established if the cable becomes disconnected and reconnected. After Auto-Negotiation is completed, it may be restarted at any time by writing 1 to bit 9 of the BMCR (register address 0x0000). A restart Auto-Negotiation request from any entity, such as a management agent, causes DP83869HM to halt data transmission or link pulse activity until the break_link_timer expires. Consequently, the Link Partner goes into link fail mode and the resume Auto-Negotiation. The DP83869HM resumes Auto-Negotiation after the break_link_timer has expired by transmitting FLP (Fast Link Pulse) bursts.