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XRT79L71
PRELIMINARY
141
1-CHANNEL DS3/E3 CLEAR-CHANNEL FRAMERLIU COMBO - CC/HDLC ARCHITECTURE
REV. P2.0.0
In this case, to terminate the Transmit DS3/E3 Framer block's transmission of the FERF indicator, then the
user only needs to set Bit 7 back to "0".
Automatic Transmission of the FERF/RDI Indicator
The XRT79L71 permits the user to configure the Transmit DS3 Framer block to automatically transmit the
FERF/RDI indicator, in response to the following conditions.
Whenever the corresponding near-end Receive DS3/E3 Framer block declares the LOS (Loss of Signal)
defect condition
Whenever the corresponding near-end Receive DS3/E3 Framer block is declaring the OOF (Out of Frame)
defect condition
Whenever the corresponding near-end Receive DS3/E3 Framer block is declaring the AIS defect condition.
Setting bits 0 through 2, within the Transmit DS3 Configuration Register, permits the user to configure the
Transmit DS3/E3 Framer block to support the Automatic Transmission of the FERF indicator upon detection of
these Red Alarm condition. These bit-fields are highlighted and defined below.
Transmit DS3 Configuration Register (Address = 0x1130)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Transmit
FERF/RDI
Indicator
Tx X-Bits
TxIdle
TxAIS
TxLOS
TxFERF
upon LOS
Defect
TxFERF
upon OOF-
Defect
TxFERF
upon AISDe-
fect
R/W
0
1
Bit Number
Name
Type
Description
2
TxFERF upon LOS
Defect
R/W
Automatic Transmission of FERF upon LOS Defect:This bit-field per-
mits the user to configure the Frame Generator block to automatically
transmit the FERF Indicator to the remote terminal, upon the Receive
DS3/E3 Framer block declaring the LOS defect condition. If this fea-
ture is enabled, then the Transmit DS3/E3 Framer block will transmit
the FERF indicator to the remote terminal for the duration that the com-
panion Receive DS3/E3 Framer block is declaring the LOS defect con-
dition. The Transmit DS3/E3 Framer block will cease to transmit the
FERF indicator once the Receive DS3/E3 Framer block has cleared
the LOS defect condition.0 - Disables the Automatic Transmission of
FERF upon declaration of the LOS defect feature.1 - Enables the Auto-
matic Transmission of FERF upon declaration of the LOS defect fea-
ture.