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XRT79L71
PRELIMINARY
529
1-CHANNEL DS3/E3 CLEAR-CHANNEL FRAMERLIU COMBO - CC/HDLC ARCHITECTURE
REV. P2.0.0
6.3.2.5.2
Clearing the FERF/RDI Defect Condition
The Receive E3 Framer block will clear the FERF/RDI Defect Condition whenever it receives a User-
Selectable number of E3 frames, in which the FERF/RDI bit-field is set to "0".
Setting the FERF/RDI Defect Clearance Criteria
The user can specify the FERF/RDI Defect Clearance Criteria, by writing the appropriate value into Bit 4
(RxFERF Algo), as depicted below.
If this bit-field is set to "0", then the Receive E3 Framer block will clear the FERF/RDI defect condition anytime
it receives at least three (3) consecutive E3 frames, in which the FERF/RDI bit-field has been set to "0".
Conversely, if this bit-field is set to "1", then the Receive E3 Framer block will clear the FERF/RDI defect
condition anytime it receives at least five (5) consecutive E3 frames, in which the FERF/RDI bit-field has been
set to "0".
Whenever the Receive E3 Framer block clears the FERF/RDI defect condition, it will do so, by doing all of the
following.
Setting Bit 0 (FERF/RD Defect DeclaredI) within the Receive E3 Configuration and Status Register # 2 to "0"
as depicted below.
Receive E3 Interrupt Status Register # 2 - G.832 (Address = 0x1115)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Unused
Change in
RxTTB
Message
Interrupt
Status
Reserved
Detection of
FEBE Event
Interrupt
Status
Change in
FERF/RDI
Defect
Condition
Interrupt
Status
Detection of
BIP-8 Error
Interrupt
Status
Detection of
Framing
Byte Error
Interrupt
Status
RxPLD
Mismatch
Interrupt
Status
R/O
RUR
R/O
RUR
0
1
0
Receive E3 Configuration and Status Register # 1 - G.832 (Direct Address = 0x1110)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
RxPLDType[2:0]
RxFERF
Algo.
RxTMark
Algo
RxPLDTypeExp[2:0]
R/O
R/W
0
1
0
X
0
1
0
Receive E3 Configuration and Status Register # 2 - G.832 (Address = 0x1111)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Receive LOF
Algo
LOF Defect
Declared
OOF Defect
Declared
LOS Defect
Declared
AIS Defect
Declared
RxPLD
Unstab
RxTMark
FERF/RDI
Defect
Declared
R/W
R/O
0