FLLXT1000BA.C4QE000 Intel, FLLXT1000BA.C4QE000 Datasheet - Page 55

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

Specifications of FLLXT1000BA.C4QE000

• Lead Free Status / RoHS Status: Not Compliant

Datasheet
Document #: 249276
Revision #: 002
Rev. Date: 07/20/01
TP<A:D>
RXD<7:0>
CRS
RXDV
RXER
Figure 27. 1000BASE-T Reception with Error
(output)
(output)
(output)
(input)
(output)
2.5.4.1.5 Carrier Extend/Packet Concatenation
To extend carrier at the end of a packet, the MAC asserts TX_ER as it simultaneously de-asserts
TX_EN at the very end of the packet. At the same time, it drives a “0F” octet on the TX_D lines.
The LXT1000 responds by terminating the packet with csreset and ESD, and then sends “Carrier
Extend” symbols on the line.
If the MAC ends the event by simply dropping TX_ER (carrier extension), the LXT1000 responds
by immediately driving idle symbols on the line. If the MAC re-asserts TX_EN at the same time it
de-asserts TX_ER (packet concatenation), the LXT1000 immediately drives SSD on the line and
then begins transmitting the packet. The LXT1000 leaves CRS asserted for the entire time that
either TX_EN or TX_ER remain asserted. If TX_EN goes High during this process, it first must
finish sending the “crsreset” and “ESD” symbols on the line, then generate SSD and continue with
normal packet encoding.
In the receive direction, the LXT1000 performs the inverse function, dropping RX_DV and
asserting RX_ER when it detects Carrier-Extend symbols on the line. The LXT1000 asserts CRS
while RX_DV or RX_ER are asserted. During carrier extend, the LXT1000 drives “0F” on the
RX_D lines.
IDLE
55
SSD
PREAMBLE/SFD
55
5D
Error
Data Symbols
Error
PACKET/FCS
Gigabit Ethernet Transceiver — LXT1000
csreset
ESD
IDLE
55