XRT72L13 Datasheet, PDF (72/370 Pages) Exar Corporation – M13 MULTIPLEXER/CLEAR CHANNEL DS3 FRAMER IC

XRT72L13 MULTIPLEXER/FRAMER IC
REV. 1.0.6
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PRELIMINARY
FIGURE 30. ILLUSTRATION OF THE XRT72L13 M13 MULTIPLEXER/FRAMER OPERATING IN THE "CLEAR CHANNEL
DS3 FRAMER LOCAL LOOP-BACK" MODE
TxOHFrame
TxOHEnable
TxOH
TxOHClk
TxOHIns
TxOHInd
TxSer
TxNib[3:0]
TxInClk
TxNibClk
TxFrame
MOTO
D[7:0]
A[8:0]
IntB*
CSB*
RdB_DS
WrB_RW
Rdy_Dtck
Reset*
ALE_AS
RxOHInd
RxSer
RxNib[3:0]
RxOutClk
RxNibClk
RxFrame
RxOHFrame
RxOH
RxOHClk
RxOHEnable
Transmit Overhead
Input
Interface Block
Transmit Payload
Data Input
Interface Block
Transmit DS3
Framer Block
Microprocessor
Interface
Receive Payload
Data Output
Interface Block
Receive Overhead
Output
Interface Block
Tx LAPD Buffer/
Controller
Rx LAPD Buffer/
Controller
Receive DS3
Framer Block
Transmit
LIU
Interface
Block
TxPOS
TxNEG
TxLineClk
Local
Loop-back
Path
Receive LIU
Interface
Block
RxPOS
RxNEG
RxLineClk
Figure 30 indicates that when the XRT72L13 has
been configured to operate in the "Clear Channel
DS3 Framer Local Loop-back" Mode, then the follow-
ing internal connections are made.
• The TxPOS output signal is routed into the RxPOS
input pin.
• The TxNEG output signal is routed into the RxNEG
input pin
• The TxLineClk output clock signal is routed into the
RxLineClk input pin.
1.2.1.1.2 Remote Loop-back Mode
Figure 31 presents an illustration of the XRT72L13
M13 Multiplexer/Framer IC operating in the "Clear
Channel DS3 Framer Remote Loop-back" Mode.
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