RTL8211C & RTL8211CL
Datasheet
6.6.1. Auto-Negotiation Priority Resolution
Upon the start of auto-negotiation, to advertise its capabilities each station transmits a 16-bit packet called
a Link Code Word (LCW), within a burst of 17 to 33 Fast Link Pulses (FLP). A device capable of
auto-negotiation transmits and receives the FLPs. The receiver must identify three identical LCWs before
the information is authenticated and used in the arbitration process. The devices decode the base LCW and
select capabilities with the highest common denominator supported by both devices.
To advertise 1000Base-T capability, both link partners, sharing the same link medium, should engage in
Next Page (1000Base-T Message Page, Unformatted Page 1, and Unformatted Page 2) exchange.
Auto-negotiation ensures that the highest priority protocol will be selected as the link speed based on the
following priorities advertised through the Link Code Word (LCW) exchange. Refer to IEEE 802.3 Clause
28 for detailed information.
1. 1000Base-T Full Duplex (highest priority)
2. 1000Base-T Half Duplex
3. 100Base-Tx Full Duplex
4. 100Base-Tx Half Duplex
5. 10Base-T Full Duplex
6. 10Base-T Half Duplex (lowest priority)
6.6.2. Auto-Negotiation Master/Slave Resolution
To establish a valid 1000Base-T link, the Master/Slave mode of both link partners should be resolved
through the auto-negotiation process:
Master Priority:
Multi-port > Single port
Manual > Non-manual
Determination of Master/Slave configuration from LCW:
Manual_MASTER=U0*U1
Manual_SLAVE=U0*!U1
Single-port device=!U0*!U2
Integrated 10/100/1000 Gigabit Ethernet Transceiver
16
Track ID: JATR-1076-21 Rev. 1.3
ETC [ ETC ]
