Achronix Speedster22i 10G/40G/100G Ethernet - Manual (Page 54)

54 UG029, September 6, 2013
Auto-Negotiation
Overview
Each PCS layer implements an auto-negotiation function that allows the local device to
advertise supported modes of operation to another device at the remote end of an Ethernet
link, and to detect corresponding operational modes the remote device may be advertising. It
is used in backplane applications (Base-KR).
The auto-negotiation function in the PCS layers does not implement Parallel Detection in
hardware due to the ambiguity of the PCS interface for 10G, 40G and 100G modes of
operation. It is therefore the responsibility of the application layer to perform Parallel
Detection when the remote device does not support auto-negotiation or when auto-
negotiation is disabled.
The page exchange between link partners is done through the auto-negotiation function registers
function registers (KXAN_CONTROL, KXAN_STATUS, KXAN_ABILITY_0/1/2,
KXAN_REM_ABILITY_0/1/2, AN_XNP_0/1/2, LP_AN_XNP_0/1/2, BP_ETH_STATUS,
BP_ETH_STATUS,
see