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2 CHANNEL E3/DS3/STS-1 LINE INTERFACE UNIT
XRT7302
PIN DESCRIPTION
PIN #
14
SIGNAL NAME
LCV1
15
RLOL1
16
EXClk1
17
CS/(ENDECDIS)
REV. 1.1.0
TYPE
O
O
I
I
DESCRIPTION
Line Code Violation Indicator - Channel 1:
Whenever the Receive Section of Channel 1 detects a Line Code Violation,
then it will pulse this output pin "high". This output pin will remain "low" at all
other times.
The XRT7302 device will output an NRZ pulse via this output pin. Hence, the
user is advised to sample this output pin via the RxClk2 clock output signal.
Receive Loss of Lock Output Indicator - Channel 1:
This output pin toggles "high" if Channel 1, within the XRT7302 device has
detected a "Loss of Lock" Condition. Channel 1 will declare an LOL (Loss of
Lock) Condition if the recovered clock frequency deviates from the Reference
Clock frequency (available at the ExClk input pin) by more than 0.5%.
External Reference Clock Input - Channel 1:
The user is expected to apply a 34.368 MHz clock signal (for E3 applications),
a 44.736 MHz clock signal (for DS3 applications), or a 51.84 MHz clock signal
(for SONET STS-1 applications).
NOTES:
1. It is permissible for one to use the same clock, which is also driving
the "TxClk" input pin.
2. It is permissible to operate Channel 1 at a different data rate than from
Channel 2.
Microprocessor Serial Interface - Chip Select Input/Encoder-Decoder
Disable Input:
The exact functionality of this pin depends upon whether the XRT7302 device
is operating in the Host or Hardware Mode.
Host Mode Operation - Chip Select Input (for the Microprocessor Serial
Interface):
The Local Microprocessor must assert this pin (e.g., set it to "0") in order to
enable communication with the XRT7302, via the Microprocessor Serial Inter-
face. (Note: This pin is internally pulled "high".)
Hardware Mode - B3ZS/HDB3 Encoder & Decoder Disable:
Setting this input pin "high" disables the "B3ZS/HDB3 Encoder & Decoder"
blocks (within the XRT7302 device) and configures the XRT7302 device to
transmit and receive the line signal in an AMI format. Conversely, setting this
input pin "low" enables the "B3ZS/HDB3 Encoder & Decoder" blocks and con-
figures the XRT7302 device to transmit and receive the line signal in the B3ZS
format, (for DS3/STS-1 operation) or in the HDB3 format, (for E3 operation).
NOTE: If the XRT7302 device is operating in the "Hardware" Mode, then this
pin setting configures the "B3ZS/HDB3" Encoder and Decoder Blocks for both
Channels 1 and 2.
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