XRT72L54 Datasheet, PDF (42/484 Pages) Exar Corporation – FOUR CHANNEL DS3/E3 FRAMER IC WITH HDLC CONTROLLER

XRT72L54
FOUR CHANNEL DS3/E3 FRAMER IC WITH HDLC CONTROLLER
REV. P1.1.2
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PRELIMINARY
PIN DESCRIPTION
PIN #
T1
T2
T3
T4
T17
T18
PIN NAME
RLOL[2]
ExtLOS[3]
RxOOF[2]
RxAIS[3]
RxClk[2]
NibbleIntf
T19
Reset
T20
MOTO
U1
RxOOF[3]
U2
RxLOS[3]
U3
RxAIS[2]
U4
GND
U5
RLOOP[2]
U6
VDD
TYPE
I
I
O
O
O
I
I
I
O
O
O
****
O
****
DESCRIPTION
See Description for Pin B8
See Description for Pin D9
See Description for Pin A3
See Description for Pin C5
See Description for Pin D20
Nibble Interface Select Input Pin:
This input pin allows the user to configure the Transmit Payload Data
Input Interface and the Receive Payload Data Output Interface to oper-
ate in either the "Serial-Mode" or the "Nibble/Parallel-Mode".
Setting this input pin "high" configures the Transmit and Receive Termi-
nal Interfaces to operate in the "Nibble/Parallel-Mode". In this mode, the
“Transmit Payload Data Input Interface” block will accept the “outbound”
payload data (from the Terminal Equipment) in a “nibble-parallel” man-
ner via the “TxNib[3:0]” input pins. Further, the “Receive Payload Data
Output Interface” block will output the “inbound” payload data (to the
Terminal Equipment) in a “nibble-parallel” manner via the “RxNib[3:0]”
output pin.
Setting this input pin "low" configures the Transmit and Receive Termi-
nal Interfaces to operate in the "Serial" Mode. In this mode, the “Trans-
mit Payload Data Input Interface” block will accept the “outbound”
payload data (from the Terminal Equipment) in a “serial” manner via the
“TxSer” input pin. Further, the “Receive Payload Data Output Interface”
block will output the “inbound” payload data (to the Terminal Equipment)
in a “serial” manner via the “RxSer” output pin.
Reset Input:
When this "active-low" signal is asserted, the Framer device will be
asynchronously reset. Additionally, all outputs will be "tri-stated", and all
on-chip registers will be reset to their default values.
Motorola/Intel Processor Interface Select Mode:
This input pin allows the user to configure the Microprocessor Interface
to interface with either a "Motorola-type" or "Intel-type" microprocessor/
microcontroller. Tying this input pin to VCC, configures the microproces-
sor interface to operate in the Motorola mode (e.g., the Framer device
can be readily interfaced to a "Motorola type" local microprocessor).
Tying this input pin to GND configures the Microprocessor Interface to
operate in the Intel Mode (e.g., the Framer device can be readily inter-
faced to a “Intel type" local microprocessor).
See Description for Pin A3
See Description for Pin C4
See Description for Pin C5
Ground
See Description for Pin B7
Power Supply +3.3v ± 5%
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