XRT91L81IB View Datasheet(PDF) - Exar Corporation
Part Name
Description
MFG CO.
'XRT91L81IB' PDF : 40 Pages View PDF
XRT91L81
2.488/2.666GBPS OC-48/STM-16 SONET/SDH TRANSCEIVER
REV. P1.0.3
TABLE 12: MICROPROCESSOR REGISTER BIT DESCRIPTION
PRELIMINARY
CHANNEL 0 CONTROL REGISTER (0X05H)
BIT
NAME
FUNCTION
Register
Type
Default
Value
(HW reset)
D7
Reserved This Register Bit is Not Used
X
X
D6
Reserved This Register Bit is Not Used
X
X
D5
Reserved This Register Bit is Not Used
X
X
D4
Reserved This Register Bit is Not Used
X
X
D3
Reserved This Register Bit is Not Used
X
X
D2
DLOOP Digital Loopback
R/W
0
Digital loopback allows the Transmit input pins to be looped back
to the Receive output pins for local diagnostics. The Transmit
serial output data is valid during the digital loopback.
"0" = Disabled
"1" = Enable DLOOP
D1
RLOOPS Serial Remote Loopback
R/W
0
Serial remote loopback allows the Receive serial input pins to be
looped back to the Transmit serial output pins for remote diagnos-
tics. The Receive output data is valid during a serial remote loop-
back.
"0" = Disabled
"1" = Enable RLOOPS
D0
RLOOPP Parallel Remote Loopback
R/W
0
Parallel remote loopback has the same affect as the serial remote
loopback, except that the input data is allowed to pass through the
SIPO before it’s looped back to the Transmit path, wherein it
passes through the Transmit FIFO, through the PISO, and back
out the Transmit serial output. The Receive output data is valid
during a serial remote loopback.
"0" = Disabled
"1" = Enable RLOOPP
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