FLLXT1000BA.C4QE000 Intel, FLLXT1000BA.C4QE000 Datasheet - Page 68

• Manufacturer Part Number: FLLXT1000BA.C4QE000
• Manufacturer: Intel

Specifications of FLLXT1000BA.C4QE000

• Lead Free Status / RoHS Status: Not Compliant

LXT1000 — Gigabit Ethernet Transceiver
3.1.8
3.1.8.1
68
Figure 38. Master/Slave Relationship
Master/Slave Relationship Details
Resolution of the Master-Slave relationship is a key part of gigabit auto-negotiation. As shown in
Figure
transmission to a local clock, while. the Slave synchronizes transmission to a clock that is
recovered from the link. This keeps the transmitters on both sides of the link phase-locked to each
other, which is necessary for echo cancellation.
In connections between multi-port devices (switches, for example) and single-port devices (NICs,
for example), the typical preference is that the multi-port device be the Master and the single-port
device be the Slave. For point-to-point links there is no preference.
The Master/Slave settings are configured prior to auto-negotiation. This can be done via software
or hardware. Software configuration involves setting certain MII bits. Hardware configuration,
which provides more limited capabilities, is done via external configuration balls on the LXT1000.
Configuring Master/Slave in Software
Three MII Register bits (9.12, 9.11, 9.10) are used to configure the Master/Slave setting:
Bit 9.12
Bit 9.12 decides whether bit 9.11 or bit 9.10 is used to specify the Master/Slave setting.
If bit 9.12 = 0, then bit 9.10 is used.
If bit 9.12 = 1, then bit 9.11 is used.
Bit 9.11 is used when the Master/Slave setting is mandatory. If both sides use bit 9.11 and set it to
the same value, a deadlock results (no link can be established). Bit 9.10 is used when the Master/
Slave setting is not mandatory. If both sides use bit 9.10 and set it to the same value, the conflict is
resolved via a random number. If one side uses bit 9.11 and the other side uses bit 9.10, bit 9.11
takes precedence. The default state for bit 9.12 is 0 (select 9.10).
Bit 9.11
Bit 9.11 is used only when bit 9.12 = 1.
38, every Gigabit link has a “Master” side and a “Slave” side. The Master synchronizes
Clock
Recovery
Txcvr
SLAVE
Twisted-Pair Connection
MASTER
XI
PLL
Txcvr
Crystal
Document #: 249276
Rev. Date: 07/20/01
Revision #: 002
Datasheet