3X38FTR Datasheet, PDF (22/64 Pages) Agere Systems – OCTAL-FET (Fast Ethernet Transceiver) for 10Base-T/100Base-TX/FX

3X38FTR 208-Pin SQFP
OCTAL-FET for 10Base-T/100Base-TX/FX
Preliminary Data Sheet
September 2000
Pin Descriptions (continued)
Table 6. LED and Configuration Pins (continued)
Pin
Signal
Type
Description
197
FDUPLED_0/
SERCLK/
CRS_SEL
O Full-Duplex LED[0]. This LED output can operate as the full-duplex
LED indicator, or as a collision LED indicator, or as a serial LED output.
This output is only valid when the link is up. When the link is operating in
full-duplex mode, this LED output is the full-duplex LED (logic high out-
put). When the link is operating in half-duplex mode, this LED output
becomes the collision LED output (logic high output). 10 mA active-high
output.
O Serial LED Clock. This is approximately a 1.56 MHz clock output used
to clock out the serial LED data, when the serial LED mode is enabled
by pulling the SERIAL_LED_MODE[1] pin high and the
SERIAL_LED_MODE[0] pin low through a 10 kΩ resistor at powerup or
reset.
I Carrier Sense Select. At powerup, this pin may be used to select the
mode of CRS (carrier sense) operation. When this pin is pulled high
through a 10 kΩ resistor, CRS (carrier sense) will be asserted on
receive activity only. This is the same function as register 29, bit 10.
196
FDUPLED_1/
SERDATA/
FULL_DUP
This pin has an internal 50 kΩ pull-down resistor for normal mode oper-
ation (default: CRS asserted on transmit or receive activity). This input
and the register bit [29.10] are ORed together during powerup and
reset.
O Full-Duplex LED[1]. This LED output can operate as the full-duplex
LED indicator, or as a collision LED indicator, or as a serial LED output.
This output is only valid when the link is up. When the link is operating in
full-duplex mode, this LED output is the full-duplex LED (logic high out-
put). When the link is operating in half-duplex mode, this LED output
becomes the collision LED output (logic high output). 10 mA active-high
output.
O Serial LED Data. A single serial LED data stream output that contains
LED status information from all eight 3X38 ports. The serial LED mode
is enabled by pulling the SERIAL_LED_MODE_1 pin high through a
10 kΩ resistor, and the SERIAL_MODE_0 pin low at powerup or reset.
I Full Duplex. At powerup, this pin may be used to select full-duplex
operation for all eight channels by pulling it high through a 10 kΩ resis-
tor, if station management is unavailable. This is the same function as
register 0, bit 8. This pin has an internal 50 kΩ pull-up resistor to default
to full duplex for normal operation. This input and the register bit[0:8]
are ORed together during powerup and reset. This pin is ignored when
autonegotiation is enabled. This pin has an internal 50 kΩ pull-up to
default to full duplex.
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Lucent Technologies Inc.