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XRT79L71
PRELIMINARY
377
1-CHANNEL DS3/E3 CLEAR-CHANNEL FRAMERLIU COMBO - CC/HDLC ARCHITECTURE
REV. P2.0.0
Generating the "Change in OOF Defect Condition" Interrupt
The Receive E3 Framer block will indicate that it is generating the "Change in OOF Defect Condition" Interrupt
by doing all of the following.
a. Asserting the Interrupt Request output pin (INT*), by pulling it "low".
b. Setting Bit 3 (Change in OOF Defect Condition Interrupt Status), within the "Receive E3 Interrupt Status
Register # 1" as depicted below.
What happens if the Receive E3 Framer block transitions back into the "In-Frame" State?
If the Receive E3 Framer block (while operating in the "OOF State") is able to correctly locate the "FAS
Pattern" in three (3) consecutive E3 frames, then it will transition back into the "In-Frame" State. The Receive
E3 Framer block will inform the Microprocessor of this occurrence by doing all of the following.
Clearing the "OOF Defect Condition"
The Receive E3 Framer block will indicate that it is clearing the "OOF Defect Condition" by setting Bit 5 (OOF
Defect Declared), within the "Receive E3 Configuration and Status Register # 2", to "0" as depicted below.
Generating the "Change in OOF Defect Condition" Interrupt
The Receive E3 Framer block will indicate that it is declaring the "Change in LOF Defect Condition" Interrupt by
doing all of the following.
a. Asserting the Interrupt Request output pin (INT*), by pulling it "low".
b. Setting Bit 3 (Change in OOF Defect Condition Interrupt Status) within the "Receive E3 Interrupt Status
Register # 1" as depicted below.
Receive E3 Interrupt Status Register # 1 - G.751 (Address = 0x1114)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Unused
COFA
Interrupt
Status
Change in
OOF Defect
Condition
Interrupt
Status
Change in
LOF Defect
Condition
Interrupt
Status
Change in
LOS Defect
Condition
Interrupt
Status
Change in
AIS Defect
Condition
Interrupt
Status
R/O
RUR
0
1
0
Receive E3 Configuration and Status Register # 2 - G.751 (Address = 0x1111)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
RxLOF
Algo
LOF
Defect
Condition
Declared
OOF
Defect
Condition
Declared
LOS
Defect
Condition
Declared
AIS
Defect
Condition
Declared
Unused
FERF/RDI
Defect
Condition
Declared
R/W
R/O
0
1