STE10 Datasheet, PDF (51/66 Pages) STMicroelectronics – PCI 10/100 ETHERNET CONTROLLER WITH INTEGRATED PHY 5V

STE10/100
transmission line parasitics.
s MLT3 to NRZI Decoder and PLL for Data Recovery: Following adaptive equalizer, baseline wander,
the transceiver converts the resulting MLT3 to NRZI code, which is passed to the Phase Lock Loop
circuits in order to extract the synchronous clock and the original data.
s Data Conversions of NRZI to NRZ and Serial to Parallel: After the data is recovered, it will be passed
to the NRZI-to-NRZ converter to produce a 125MHz serial bit stream. This serial bit stream will be
packed to parallel 5B type for further processing. The NRZI to NRZ conversion may be bypassed by
clearing ENRZI (bit 7 of XR10) to 0.
s De-scrambling and Decoding of 5B/4B: The parallel 5B type data is passed to the de-scrambler and
5B/4B decoder to restore it to its original MII nibble representation.
s Carrier sensing: The Carrier Sense (CRS) signal is asserted when the transceiver detects any 2 non-
contiguous zeros within any 10-bit boundary of the receiving bit stream. CRS is de-asserted when ESD
code-group or Idle code-group is detected. In half duplex mode, CRS is asserted during packet
transmission or receive; in full duplex mode, CRS is asserted only during packet reception.
s 10BASE-T Transmission Operation
The parallel-to-serial converter, Manchester Encoder, Link test, Jabber and the transmit wave-shaper
and line driver functions described in the section of “Wave-Shaper and Media Signal Driver” of
“100BASE-T Transmission Operation” are also provided for 10BASE-T transmission. Additionally,
Collision detection and SQE test for half duplex application are provided.
s 10BASE-T Receive Operation
Carrier sense function, receiving filter, PLL for clock and data recovery, Manchester decoder, and serial
to parallel converter functions are provided to support 10BASE-T reception.
s Loop-back Operation of transceiver
The transceiver provides internal loop-back (also called transceiver loop-back) operation for both
100BASE-TX and 10BASE-T operation. The loop-back function can be enabled by setting XLBEN (bit
14 of XR0) to 1. In loop-back mode, the TX± and RX± lines are isolated from the media. The transceiver
also provides remote loop-back operation for 100BASE-TX operation. The remote loop-back operation
can be enabled by setting ENRLB (bit 9 of XR10) to 1.
In 100BASE-TX internal loop-back operation, the data is routed from the transmit output of NRZ-to-
NRZI converter and looped back to the receive input of NRZI-to-NRZ converter.
In 100BASE-TX remote loop-back operation, data is received from RX± pins and passed through the
receive path to the output of the data and clock recovery section, and then looped back to the input of
the NRZI-to-MLT3 converter and out to the medium via the transmit line drivers.
In 10BASE-T loop-back operation, the data is passed through the transmit path to the output of the
Manchester encoder and then looped back into the input of the Phase Lock Loop circuit in the receive
path.
s Full Duplex and Half Duplex Operation of Transceiver
The transceiver can operate in either full duplex or half duplex network applications. In full duplex, both
transmission and reception can take place simultaneously. In full duplex mode, collision (COL) signal is
ignored and carrier sense (CRS) signal is asserted only when the transceiver is receiving.
In half duplex mode, transmission and reception can not take place simultaneously. In half duplex
mode, the collision signal is asserted when transmitted and received signals collide, and carrier sense
is asserted during both transmission and reception.
s Auto-Negotiation Operation
The Auto-Negotiation function provides the means to exchange information between the transceiver
and the network partner to automatically configure both to take maximum advantage of their abilities.
The Auto-Negotiation function is controlled by ANEN (bit 12 of XR0).
During Auto-Negotiation information is exchanged with the network partner using Fast Link Pulses
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