XRT79L71 Datasheet, PDF (129/441 Pages) Exar Corporation – 1 - CHANNEL DS3/E3 ATM UNI/PPP COMBO IC

áç
PRELIMINARY
1 - CHANNEL DS3/E3 ATM UNI/PPP COMBO IC
TEST REGISTER (DIRECT ADDRESS = 0X110C)
BIT 7
BIT 6
BIT 5
BIT 4
TxOHSrc
Unused
RxPRBS
Lock
R/W
R/O
R/O
R/O
0
0
0
0
BIT 3
RxPRBS
Enable
R/W
0
BIT 2
TxPRBS
Enable
R/W
0
XRT79L71
REV. P1.0.3
BIT 1
BIT 0
Unused
R/O
R/O
0
0
BIT NUMBER
NAME
7
TxOHSrc
6-5
4
Unused
RxPRBS Lock
3
RxPRBS Enable
TYPE
R/W
R/O
R/O
R/W
DESCRIPTION
Transmit Overhead Bit Source:
This READ/WRITE bit-field permits the user to configure the
Frame Generator to accept and insert overhead bits/bytes which
are input via the "Payload Data Input Interface" block, as indi-
cated below.
0 - Overhead bits/bytes are internally generated by the Frame
Generator block.
1 - Overhead bits/byte data is accepted from the Payload Data
Input Interface block.NOTE: This register bit applies to all fram-
ing formats that are supported by the Frame Generator block.
PRBS Lock Indicator:
This READ-ONLY bit-field indicates whether or not the PRBS
Receiver (within the Channel) 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.
NOTE: This bit-field is not valid if the PRBS Receiver is disabled,
or if the Frame Synchronizer block is bypassed.
Receive PRBS Enable:
This READ/WRITE bit-field permits the user to either enable or
disable the PRBS Receiver within the Frame Synchronizer 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.
NOTE: This bit-field is ignored if the Frame Synchronizer block is
by-passed.
117