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XRT79L71
PRELIMINARY
527
1-CHANNEL DS3/E3 CLEAR-CHANNEL FRAMERLIU COMBO - CC/HDLC ARCHITECTURE
REV. P2.0.0
6.3.2.5
DECLARING AND CLEARING THE FERF/RDI DEFECT CONDITION
The Receive DS3/E3 Framer block has the responsibility for declaring and clearing the FERF/RDI defect
condition, as described below.
6.3.2.5.1
Declaring the FERF/RDI (Far-End Receive Failure/Remote Defect Indicator) Defect Condition
The Receive E3 Framer block will declare the FERF or RDI defect condition, if it starts to receive E3 frames in
which the FERF/RDI bit-field is set to "1".
one can configure the Transmit DS3/E3 Framer block to automatically transmit the FERF indicator to the
remote terminal, anytime and for the duration that the Near-End Corresponding Receive DS3/E3 Framer Block
declares either the LOS, LOF/OOF or AIS defect condition. Figure 249 recaps some of this discussion by
presenting a figure that depicts the Transmit DS3/E3 Framer block automatically transmitting the FERF
indicator to the remote terminal equipment by setting the FERF/RDI bit within each outbound E3 frame to "1"
because the Near-End Corresponding Receive DS3/E3 Framer block was declaring the LOS defect condition.
Receive E3 Interrupt Status Register # 1 - G.832 (Address = 0x1114)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Unused
Change in
SSM MSG
Interrupt
Status
Change in
SSM OOS
Interrupt
Status
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
FIGURE 249. A SIMPLE ILLUSTRATION OF THE NEAR-END TERMINAL EQUIPMENT TRANSMITTING THE FERF/RDI
INDICATOR TO THE REMOTE TERMINAL EQUIPMENT
Transmit E3
Framer
Receive E3
Framer
Near-End Terminal
Remote
Terminal
Equipment
Remote
Terminal
Equipment
MA Byte
1xxxxxxx
FERF/RDI bit
Declares the FERF/RDI
Defect Condition
Declares the LOS Defect
Condition