XRT79L71 Datasheet, PDF (186/441 Pages) Exar Corporation – 1 - CHANNEL DS3/E3 ATM UNI/PPP COMBO IC

XRT79L71
REV. P1.0.3
TRANSMIT DS3 RELATED REGISTERS
PRELIMINARY
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1 - CHANNEL DS3/E3 ATM UNI/PPP COMBO IC
TXDS3 CONFIGURATION REGISTER (DIRECT ADDRESS = 0X1130)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
Tx Yellow
Alarm
Tx X-Bits
TxIdle
TxAIS
TxLOS
TxFERF
upon LOS
R/W
R/W
R/W
R/W
R/W
R/W
0
0
0
0
0
1
BIT 1
TxFERF
upon OOF
R/W
1
BIT 0
TxFERF
upon AIS
R/W
1
BIT NUMBER
NAME
7
Tx Yellow Alarm
6
Tx X-Bits
5
TxIdle
TYPE
R/W
R/W
R/W
DESCRIPTION
Transmit Yellow Alarm (FERF) indicator:
This READ/WRITE bit-field permits the user to force the Frame
Generator block to transmit the FERF condition by setting both of
the X-bits (within each outbound DS3 frame) to "0".
0 - "X" bits are set to the appropriate value, depending upon
receive conditions (as detected by the Frame Synchronizer
block).
1 - "X" bits are forced to "0" and the FERF indicator is transmit-
ted to the remote terminal equipment.
Force X bits to "1":
This READ/WRITE bit-field permits the user to force the Frame
Generator block to set the X-bits (within each outbound DS3
frame) to "1".
0 - "X" bits are set to the appropriate value, depending upon
receive conditions (as detected by the Frame Synchronizer
block).
1 - "X" bits are forced to "1".
Transmit DS3 Idle Signal:
This READ/WRITE bit-field permits the user to force the Frame
Generator block to transmit an Idle signal condition to the remote
terminal equipment.
0 - Normal traffic is generated and transmitted by the Frame
Generator block.
1 - Frame Generator block transmits the DS3 Idle Pattern.
NOTES:
1. This bit-field is ignored if "TxAIS" or "TxLOS" bit-fields
are set to "1".
2. The exact pattern that the Frame Generator transmits
(whenever this bit-field is set to "1") depends upon the
contents within Bits 3 through 0 (Tx_Idle_Pattern[3:0])
within the "Transmit DS3 Pattern" Register (Direct
Address = 0x114C).
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