![](http://datasheet.mmic.net.cn/Exar-Corporation/XRT94L33IB-L_datasheet_100163/XRT94L33IB-L_337.png)
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XRT94L33
3-CHANNEL DS3/E3/STS-1 TO STS-3/STM-1 MAPPER IC DATA SHEET
Rev.1.2.0.
337
2.3.1.2.4
Configuring the Receive STS-3 TOH Processor block to automatically transmit the AIS-P
indicator, in the Downstream Direction (towards the Receive STS-3c POH Processor
blocks) whenever it declares the LOS Defect Condition
The user can configure the Receive STS-3 TOH Processor block to automatically transmit the AIS-P
indicator, in the down-stream direction (towards the corresponding Receive STS-3c POH Processor block)
whenever (and for the duration that) it declares the LOS defect condition.
Note:
If the XRT94L33 is configured to operate in either the “1-Channel STS-3 ATM UNI/PPP” Mode, then the Receive
STS-3 TOH Processor block will transmit the AIS-P indicator to all three Receive SONET POH Processor
blocks, in parallel, whenever it declares the LOS defect condition.
Figure 80 presents an illustration of the Receive STS-3 TOH Processor block transmitting the AIS-P indicator,
in the down-stream direction (towards the Receive STS-3c POH Processor block) whenever it declares the
LOS defect condition.
Figure 80 An Illustration of the Receive STS-3 TOH Processor block transmitting the AIS-P indicator,
in the down-stream direction (towards the Receive STS-3c POH Processor blocks) whenever it
declares the LOS defect condition
Transmit
UTOPIA
Interface
Block
Transmit
UTOPIA
Interface
Block
Receive
UTOPIA/
Interface
Block
Receive
UTOPIA/
Interface
Block
Transmit
ATM
Cell Processor
Block
Transmit
ATM
Cell Processor
Block
Receive
ATM
Cell Processor
Block
Receive
ATM
Cell Processor
Block
Transmit
PPP
Processor
Block
Transmit
PPP
Processor
Block
Receive
PPP
Processor
Block
Receive
PPP
Processor
Block
Receive
STS-3/12
TOH
Processor
Block
Receive
STS-3/12
TOH
Processor
Block
Transmit
STS-3/12
TOH
Processor
Block
Transmit
STS-3/12
TOH
Processor
Block
Receive
STS-3/12
POH
Processor
Block
Receive
STS-3/12
POH
Processor
Block
Transmit
STS-3/12
POH
Processor
Block
Transmit
STS-3/12
POH
Processor
Block
STS-3/12
Telecom
Bus
Interface
Block
STS-3/12
Telecom
Bus
Interface
Block
STS-3/12
PECL
Interface
Block
STS-3/12
PECL
Interface
Block
STS-3/12
CDR
Block
STS-3/12
CDR
Block
XRT95L34 – Channel 0
Transmit
POS-PHY
Interface
Block
Transmit
POS-PHY
Interface
Block
Receive
POS-PHY
Interface
Block
Receive
POS-PHY
Interface
Block
Clock
Synthesizer
Block
Clock
Synthesizer
Block
Microprocessor
Interface
Block
Microprocessor
Interface
Block
LOS
AIS-P
The user can implement this configuration by setting Bits 1 (Transmit AIS-P [down-stream] upon LOS) and 0
(AUTO AIS), within the “Receive STS-3 Transport – Auto AIS Control” Register, to “1” as depicted below.