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XRT79L71
PRELIMINARY
209
1-CHANNEL DS3/E3 CLEAR-CHANNEL FRAMERLIU COMBO - CC/HDLC ARCHITECTURE
REV. P2.0.0
The Receive DS3 Framer block will also generate the Change of LOS Defect Condition interrupt request, by
asserting the Interrupt Output pin (e.g., by pulling it "Low"), and setting Bit 6 (Change of LOS Defect
Condition Interrupt Status), within the Receive DS3 Interrupt Status Register, to "1" as illustrated below.
NOTE: The LOS Defect Declaration Criteria for the Receive DS3/E3 LIU Block will be discussed in Section 4.3.1.6. 4.3.2.3.2
Clearing the LOS Defect Condition
The Receive DS3 Framer block will clear the LOS defect condition when both of the following conditions are
met.
a. When at least 60 out of 180 consecutive received bits within the incoming DS3 data-stream are "1s"
b. When the Receive DS3/E3 LIU Block clears the LOS defect condition.
The Receive DS3 Framer block will indicate that it is clearing the LOS defect condition by
Setting Bit 6 (LOS Defect Declared) within the Receive DS3 Configuration and Status Register to "0", as
depicted below.
The Receive DS3 Framer block will also generate the Change of LOS Defect Condition interrupt, by asserting
the Interrupt Output pin (e.g., by pulling it "Low"), and setting Bit 6 (Change of LOS Defect Condition Interrupt
Status), within the Receive DS3 Interrupt Status Register, to "1" as illustrated below.
Receive DS3 Configuration and Status Register (Address = 0x1110)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
RxAIS
Defect
Declared
LOS Defect
Declared
RxIdle
Condition
Detected
RxOOF
Defect
Declared
Unused
Framing with
Valid P-Bits
F-Sync Algo
M-Sync Algo
R/O
R/W
0
1
0
1
0
Receive DS3 Interrupt Status Register (Address = 0x1113)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Detection of
CP Bit Error
Interrupt
Status
Change of
LOS Defect
Condition
Interrupt
Status
Change of
AIS Defect
Condition
Interrupt
Status
Change of
DS3 Idle
Condi-
tion
Inter-
rupt
Status
Change of
FERF Defect
Condition
Interrupt
Status
Change of
AIC State
Interrupt
Status
Change of
OOF Defect
Condition
Interrupt
Status
Detection of
P-Bit Error
Interrupt
Status
RUR
0
1
0
Receive DS3 Configuration and Status Register (Address = 0x1110)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
AIS Defect
Declared
LOS Defect
Declared
Idle Condi-
tion Detected
OOF Defect
Declared
Unused
Framing with
Valid P-Bits
F-Sync Algo
M-Sync Algo
R/O
R/W
0