lxt9763 Intel Corporation, lxt9763 Datasheet - Page 35

• Manufacturer Part Number: lxt9763
• Description: Fast Ethernet 10/100 Hex Transceiver With Full Mii
• Manufacturer: Intel Corporation

1.12
1.12.1
1.12.1.1
1.12.2
Datasheet
Monitoring Operations
Monitoring Auto-Negotiation
Auto-negotiation can be monitored as follows:
Monitoring Next Page Exchange
The LXT9763 offers an Alternate Next Page mode to simplify the next page exchange process.
Normally, bit 6.1 (Page Received) remains set until read. When Alternate Next Page mode is
enabled (16.1 = 1), bit 6.1 is automatically cleared whenever a new negotiation process takes place.
This prevents the user from reading an old value in 6.1 and assuming that Registers 5 and 8
(Partner Ability) contain valid information. Additionally, the LXT9763 uses bit 6.5 to indicate
when the current received page is the base page. This information is useful for recognizing when
next pages must be resent due to a new negotiation process starting. Bits 6.1 and 6.5 are cleared
when read.
Per-Port LED Driver Functions
The LXT9763 incorporates three direct drive LEDs per port. On power up all the LEDs will light
for approximately 1 second after reset de-asserts. Each LED can be programmed to one of several
different display modes using the LED Configuration Register. Each per-port LED can be
programmed (refer to
The LEDs can also be programmed to display various combined status conditions. For example,
setting bits 20.15:12 = 1101 produces the following combination of Link and Activity indications:
The LED driver pins are also used to provide initial configuration settings. The LED pins are
sensitive to polarity and will automatically pull up or pull down to configure for either open drain
or open source circuits (10mA max current rating) as required by the hardware configuration. Refer
to the discussion of
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Bit 17.7 is set to 1 once the auto-negotiation process is completed.
Bits 1.2 and 17.10 are set to 1 once the link is established.
Additional bits in Register 1 (refer to
on page
Operating Speed
Transmit Activity
Receive Activity
Collision Condition
Link Status
Duplex Mode
If Link is down LED is off.
If Link is up LED is on.
If Link is up AND activity is detected, the LED will blink at the stretch interval selected by
bits 20.3:2 and will continue to blink as long as activity is present.
68) can be used to determine the link operating conditions and status.
“Hardware Configuration Settings” on page 23
Table 51 on page
Fast Ethernet 10/100 Hex Transceiver with Full MII — LXT9763
71) to indicate one the following conditions:
Table 39 on page
62) and Register 17 (refer to
for details.
Table 48
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