8101 Datasheet, PDF (58/172 Pages) LSI Computer Systems – Gigabit Ethernet Controller

Any of the following conditions iniatiate the AutoNegotiation algorithm:
• Controller reset
• AutoNegotiation restart bit set
• /C/ ordered sets received from remote end
• Controller reacquires receive word synchronization
After a negotiation has been initiated the controller uses the contents of
“Register 21–AutoNegotiation Base Page Transmit‚" Section 4.3.18, to
advise a remote device of its capabilities. The remote device does the
same, and the capabilities read back from the remote device are stored
in the AutoNegotiation Base Page Receive register. The controller's
capabilities can then be externally compared to the capabilities received
from the remote device, and the device can then be configured for a
compatible mode of operation. The controller also has next page
capability. For a complete description of the AutoNegotiation algorithm in
the controller, refer to IEEE 802.3z specification, clause 37.
If the 8B10B PCS receiver has lost word synchronization, the controller
needs to acquire synchronization before AutoNegotiation words can be
successfully received. While it is in the loss of synchronization state, the
transmitter outputs /C/ ordered sets with the remote fault bits set to
RF[1:0] = 0b01 to indicate the link failure condition to the remote end.
After the 8B10B PCS receiver has acquired word synchronization, the
negotiation process is ready to begin.
2.15.1 Next Page
The controller also has the next page capability defined in IEEE 802.3z.
The next page feature allows the transfer of additional 16-bit data words
between stations during a negotiation sequence in addition to the original
base page message information. These additional 16-bit data words are
referred to as next pages and can contain any arbitrary data.
If a next page is to be transmitted, the NP bit must be set in
“Register 21–AutoNegotiation Base Page Transmit‚" Section 4.3.18, to
indicate this to the remote station. Conversely, if a remote station wants
to send a next page to the controller, it sets the NP bit in the base page,
which is stored in “Register 22–AutoNegotiation Base Page Receive‚"
Section 4.3.19. The next pages to be transmitted to the remote station
have to be written into “Register 23–AutoNegotiation Next Page
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Functional Description
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