Draft 6/5/00
2-34
Functional Description
Copyright 2000 by LSI Logic Corporation. All rights reserved.
Remote End Capability register. The L80223 negotiation algorithm then
matches its capabilities to the remote device's capabilities and
determines the device configuration according to the priority resolution
algorithm defined in IEEE 802.3 Clause 28.
When the negotiation process is completed, the L80223 then configures
itself for either 10 or 100 Mbits/s mode and either Full- or Half-Duplex
modes (depending on the outcome of the negotiation process), and it
switches to either the 100BASE-TX or 10BASE-T link integrity algorithms
(depending on which mode was enabled through AutoNegotiation). Refer
to IEEE 802.3 Clause 28 for more details.
2.2.11.4 AutoNegotiation Outcome Indication
The outcome or result of the AutoNegotiation process is stored in the
10/100 Speed Detect (SPD_DET) and Duplex Detect (DPLX_DET) bits
in the MI serial port Status Output register.
2.2.11.5 AutoNegotiation Status
To monitor the status of the AutoNegotiation process, simply read the
AutoNegotiation Acknowledgement (ANEG_ACK) bit in the MI serial port
Status register. The ANEG_ACK bit is 1 when an AutoNegotiation has
been initiated and successfully completed.
2.2.11.6 AutoNegotiation Enable
To enable the AutoNegotiation algorithm, set the AutoNegotiation Enable
bit (ANEG_EN) in the MI serial port Control register, or assert the ANEG
pin. To disable the AutoNegotiation algorithm, clear the ANEG_EN bit, or
deassert the ANEG pin.
When the AutoNegotiation algorithm is enabled, the device halts all
transmissions including link pulses for 1200 to 1500 ms, enters the Link
Fail State, and restarts the negotiation process. When the
AutoNegotiation algorithm is disabled, the selection of 100 Mbits/s or
10 Mbits/s mode is determined with the SPEED bit in the MI serial port
Control register, and the selection of Half- or Full-Duplex mode
determined from the state of the DPLX bit in the MI serial port Control
register.