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XRT79L71
PRELIMINARY
137
1-CHANNEL DS3/E3 CLEAR-CHANNEL FRAMERLIU COMBO - CC/HDLC ARCHITECTURE
REV. P2.0.0
This step configures the Transmit DS3/E3 Framer block to force all of the C-bits to "0" whenever it is
commanded to transmit the DS3 AIS indicator.
STEP 2 - Command the Transmit DS3/E3 Framer block to transmit the DS3 AIS indicator.
This is accomplished by setting Bit 4 (Tx AIS) to "1" as depicted below.
NOTES:
1.
The user can command the Transmit DS3/E3 Framer block to terminate its transmission of the DS3 AIS pattern by
setting Bit 4 (TxAIS) back to "0".
2.
Bit 4 (TxAIS) is ignored for the duration that Bit 3 (TxLOS) is set to "1".
Forcing the tranmission of the Relaxed GR-499-CORE Compliant DS3 AIS pattern, upon Software
Control
The user can force the Transmit DS3/E3 Framer block to transmit the Relaxed Bellcore GR-499-CORE
Compliant DS3 AIS indicator upon software command by executing the following steps.
STEP 1 - Set Bit 6 (DS3 AIS Non-Stuck Stuff), within the Transmit DS3 Pattern Register to "1", as
depicted below.
This step configures the Transmit DS3/E3 Framer block to NOT force all of the C-bits to "0" whenever it is
commanded to transmit the DS3 AIS indicator.
STEP 2 - Command the Transmit DS3/E3 Framer block to transmit the DS3 AIS indicator.
This is accomplished by setting Bit 4 (Tx AIS) to "1" as depicted below.
Transmit DS3 Pattern Register (Address = 0x114C)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
TxAIS -
Unframed All
Ones
DS3 AIS
Non-Stuck
Stuff
Unused
TxLOS
Pattern
Transmit_Idle_Pattern[3:0]
R/W
R/O
R/W
0
1
0
Transmit DS3 Configuration Register (Address = 0x1130)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Tx Yellow
Alarm
Tx X-Bits
TxIdle
TxAIS
TxLOS
TxFERF
upon LOS
TxFERF
upon OOF
TxFERF
upon AIS
R/W
0
1
0
1
Transmit DS3 Pattern Register (Address = 0x114C)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
TxAIS -
Unframed All
Ones
DS3 AIS
Non-Stuck
Stuff
Unused
TxLOS
Pattern
Transmit_Idle_Pattern[3:0]
R/W
R/O
R/W
0
1
0
1
0