XRT79L71_1 Datasheet, PDF (218/434 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
LIU Alarm Status Register (Address = 0x1303)
BIT 7
BIT 6
BIT 5
BIT 4
Unused
Digital
LOS
Defect
Declared
Analog
LOS
Defect
Declared
R/O
R/O
R/O
R/O
0
0
0
0
BIT 3
FL
(FIFO Limit)
Alarm
Declared
R/O
0
BIT 2
Receive
LOL
Defect
Declared
R/O
0
BIT 1
Receive
LOS
Defect
Declared
R/O
0
BIT 0
Transmit
DMO
Condition
R/O
0
BIT
NUMBER
NAME
7 - 6 Unused
5
Digital LOS Defect
Declared
TYPE
R/O
R/O
DEFAULT
VALUE
0
0
DESCRIPTION
Digital LOS Defect Declared:
This READ-ONLY bit-field indicates whether or not the Digi-
tal LOS (Loss of Signal) detector (within the Receive DS3/
E3 LIU Block) is declaring the LOS Defect condition.
For DS3 application, the Digital LOS Detector (within the
Receive DS3/E3 LIU Block) will declare the LOS Defect
condition whenever it detects an absence of pulses (within
the incoming DS3 data-stream) for 160 consecutive bit-peri-
ods.
Further, (again for DS3 applications) the Digital LOS Detec-
tor will clear the LOS Defect condition whenever it deter-
mines that the pulse density (within the incoming DS3
signal) is at least 33%.
0 - Indicates that the Digital LOS Detector (within the
Receive DS3/E3 LIU Block) is NOT declaring the LOS
Defect Condition.
1 - Indicates that the Digital LOS Detector (within the
Receive DS3/E3 LIU Block) is currently declaring the LOS
Defect condition.
NOTES:
1. LOS Detection (within the Receive DS3/E3 LIU
Block) is performed by both an Analog LOS
Detector and a Digital LOS Detector. The LOS
state of a given Channel is simply a WIRED-OR of
the LOS Defect Declare states of these two
detectors.2.
2. The current LOS Defect Condition (per the
Receive DS3/E3 LIU Block) can be determined by
reading out the contents of Bit 1 (Receive LOS
Defect Declared) within this register.
3. This particular bit-field reflects the LOS condition,
as declared by the Receive DS3/E3 LIU Block.
The Receive DS3/E3 Framer block also has its
own LOS Defect Declare bit-field as well.
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