82540EP Datasheet, PDF (18/46 Pages) Intel Corporation – 82540EP Gigabit Ethernet Controller

82540EP — Networking Silicon
3.5
3.5.1
PHY Signals
Crystal Signals
3.5.2
Symbol
XTAL1
XTAL2
Type
Name and Function
Crystal One. The Crystal One pin is a 25 MHz +/- 30 ppm input signal. It can be
I
connected to either an oscillator or crystal. If a crystal is used, Crystal Two (XTAL2)
must also be connected.
Crystal Two. Crystal Two is the output of an internal oscillator circuit used to drive a
O
crystal into oscillation. If an external oscillator is used in the design, XTAL2 must be
disconnected.
Analog Signals
Symbol
REF
MDI[0]+/-
MDI[1]+/-
MDI[2]+/-
MDI[3]+/-
Type
Name and Function
P
Reference. This Reference signal should be connected to VSS through an external
2.49 K  resistor.
Media Dependent Interface [0].
1000BASE-T: In MDI configuration, MDI[0]+/- corresponds to BI_DA+/-, and in MDI-X
configuration, MDI[0]+/- corresponds to BI_DB+/-.
A
100BASE-TX: In MDI configuration, MDI[0]+/- is used for the transmit pair, and in MDI-X
configuration, MDI[0]+/- is used for the receive pair.
10BASE-T: In MDI configuration, MDI[0]+/- is used for the transmit pair, and in MDI-X
configuration, MDI[0]+/- is used for the receive pair.
Media Dependent Interface [1].
1000BASE-T: In MDI configuration, MDI[1]+/- corresponds to BI_DB+/-, and in MDI-X
configuration, MDI[1]+/- corresponds to BI_DA+/-.
A
100BASE-TX: In MDI configuration, MDI[1]+/- is used for the receive pair, and in MDI-X
configuration, MDI[1]+/- is used for the transit pair.
10BASE-T: In MDI configuration, MDI[1]+/- is used for the receive pair, and in MDI-X
configuration, MDI[1]+/- is used for the transit pair.
Media Dependent Interface [2].
1000BASE-T: In MDI configuration, MDI[2]+/- corresponds to BI_DC+/-, and in MDI-X
A
configuration, MDI[2]+/- corresponds to BI_DD+/-.
100BASE-TX: Unused.
10BASE-T: Unused.
Media Dependent Interface [3].
1000BASE-T: In MDI configuration, MDI[3]+/- corresponds to BI_DD+/-, and in MDI-X
A
configuration, MDI[3]+/- corresponds to BI_DC+/-.
100BASE-TX: Unused.
10BASE-T: Unused.
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