9.1.3. Functional Description
Nios® CPU subsystem executes the AN/LT firmware. CSR blocks provide interface to the client logic.
Once configured and brought out of reset, the AN/LT functionality is automatic. To ensure the autoconnection expected behavior, connect anlt_link port from F-tile AN/LT IP to the Ethernet IP.
Based on configuration, the F-tile AN/LT IP begins the auto-negotiation and link training flows and the Ethernet IP function is temporarily disabled. Once AN/LT is complete, the Ethernet IP re-enables into a data mode and behaves as a standard Ethernet port. Depending on the configuration, if the RX Ethernet link goes down, the AN/LT IP may restart the auto-negotiation flow.
You can access the F-tile AN/LT IP CSR registers at any time to monitor status, change configuration, or interrupt or restart the flow for any of the Ethernet ports connected to that AN/LT IP instance.