FLLXT1000BA.C4QE000 Intel, FLLXT1000BA.C4QE000 Datasheet - Page 43

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

Specifications of FLLXT1000BA.C4QE000

• Lead Free Status / RoHS Status: Not Compliant

2.4.7.3
2.4.8
2.4.9
2.4.9.1
Datasheet
Document #: 249276
Revision #: 002
Rev. Date: 07/20/01
1000 A/N
100 A/N
10 A/N
Table 22. Transmission Pattern If Link Is Down
Speed
10BASE-T
For 10BASE-T links, the LXT1000 and its link partner begin exchanging Normal Link Pulses
(NLPs). The LXT1000 transmits an NLP every 16 ms, and expects to receive one every 10 to
20 ms. The link is maintained as long as normal link pulses are received.
Taking Down the Link
The LXT1000 takes down an established link when the required conditions are met. For 100/1000
links, this occurs some time after valid idle codes are not received. For 10 links, this occurs after a
sufficient number of Normal Link Pulses (NLPs) are not sensed.
When link is down, transmission of data is halted until the link is re-established. What is
transmitted depends on whether auto-negotiation is enabled or not. If auto-negotiation is enabled,
the LXT1000 re-enters the auto-negotiation phase and begins transmitting Fast Link Pulses (FLPs).
If auto-negotiation is disabled, the LXT1000 continues to transmit idle symbols (100/1000) or
NLPs, but inhibits transmission of data. For 1000TX links, the LXT1000 re-enters the training
phase.
Table 22
Link Enhancements
The LXT1000 offers three enhanced link functions, each of which are discussed in the sections that
follow:
SmartSpeed
SmartSpeed is an enhancement to auto-negotiation that allows the LXT1000 to react intelligently
to network conditions that prohibit establishment of a 1000BASE-T link, such as cable problems.
Such problems may allow auto-negotiation to complete, but then inhibit completion of the training
phase. Normally, if a 1000BASE-T link fails, the LXT1000 returns to the auto-negotiation state
with the same speed settings indefinitely. With SmartSpeed enabled, after three failed attempts, the
LXT1000 automatically downgrades the highest ability it advertises to the next lower speed: from
1000 to 100 to 10. Once a link is established, and if it is later broken, the LXT1000 automatically
upgrades the capabilities advertised to the original setting. This allows the LXT1000 to
automatically recover once the cable plant is repaired.
4DPAM5 stream
MLT3 stream
Normal Link Pulses (NLPs)
•
•
•
SmartSpeed
Auto-Negotiate Isolation
Flow Control
Link Established By
summarizes these relationships.
Return to training phase
Continue transmitting idle
Continue transmitting NLPs
A/N Disabled
What Happens When Link Goes Down
Gigabit Ethernet Transceiver — LXT1000
Return to Auto-Negotiation
A/N Enabled
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