XRT79L71_1 Datasheet, PDF (80/434 Pages) Exar Corporation – 1-CHANNEL DS3/E3 ATM UNI/PPP/CLEAR-CHANNEL FRAMER IC -

XRT79L71
1-CHANNEL DS3/E3 ATM UNI/PPP/CLEAR-CHANNEL FRAMER IC - REGISTER/MAP DESCRIPTION
REV. 1.0.0
BIT NUMBER
NAME
7
TxOHSrc
6-5
4
Unused
RxPRBS Lock
3
RxPRBS Enable
2
TxPRBS Enable
1-0
Unused
TYPE
R/W
R/O
R/O
R/W
R/W
R/O
DESCRIPTION
Transmit Overhead Bit Source:
This READ/WRITE bit-field permits the user to configure the
Transmit DS3/E3 Framer block to accept and insert overhead
bits/bytes which are input via the Transmit Payload Data Input
Interface block, as indicated below
.0 - No overhead bit insertion will occur. Overhead bits/bytes are
internally generated by the Transmit DS3/E3 Framer block.
1 - Overhead bit insertion will occur. In this case, the overhead
bits/byte data is accepted from the Transmit Payload Data Input
Interface block.
NOTE: This register bit applies to all framing formats that are
supported by the Transmit DS3/E3 Framer block.
PRBS Lock Indicator:
This READ-ONLY bit-field indicates whether or not the PRBS
Receiver (within the XRT79L71) has acquired PRBS Lock with
the payload data of the incoming DS3 or E3 data stream.
0 - PRBS Receiver does not have PRBS Lock with the incoming
data stream.
1 - PRBS Receiver does have PRBS Lock with the incoming
data stream.
Receive PRBS Enable:
This READ/WRITE bit-field permits the user to either enable or
disable the PRBS Receiver within the Receive DS3/E3 Framer
block. Once the user enables the PRBS Receiver, then it will
proceed to attempt to acquire and maintain pattern (or PRBS
Lock) within the payload bits, within the incoming DS3 or E3 data
stream.
0 - Disables the PRBS Receiver.
1 - Enables the PRBS Receiver.
Transmit PRBS Enable:
This READ/WRITE bit-field permits the user to either enable or
disable the PRBS Generator within the Transmit DS3/E3 Framer
block. Once the user enables the PRBS Generator block, then it
will proceed to insert a PRBS pattern into the payload bits, within
the outbound DS3 or E3 data stream.
0 - Disables the PRBS Generator.
1 - Enables the PRBS Generator.
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