xrt94l33 Exar Corporation, xrt94l33 Datasheet - Page 179

• Manufacturer Part Number: xrt94l33
• Description: Multi-channel, Multi-function Device Aggregates 3 Ds3/e3/sts-1 Into Oc3/stm-1
• Manufacturer: Exar Corporation

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3-CHANNEL DS3/E3/STS-1 TO STS-3/STM-1 MAPPER IC DATA SHEET
Figure 22: Illustration of the “Transmit ATM Cell Processor” Functional Block Diagram with the
“Transmit User-Cell Filter” block highlighted
The Transmit ATM Cell Processor block consists of four parallel User Cell Filters. These User Cell Filters are
connected in parallel, in the sense that the entire “transmit” ATM cell traffic will be presented to the inputs of
each of the four “user-cell” filters, at the same time. Figure 23 attempts to clarify this phenomenon by
presenting an illustration as to how each of these user cell filters is connected to the ATM traffic.
Transmit UTOPIA
Interface Block
TxFIFO
TxFIFO
Main Data Path
Generator
Checker
Generator
Checker
Parity
Idle Cell
Block
Parity
Idle Cell
Block
User Cell
Calculation
HEC Byte
User Cell
Calculation
Insertion
HEC Byte
Filter
Block
Insertion
179
Filter
Block
Block
Block
&
&
Cell Extraction
Cell Insertion
Cell Extraction
Transmit GFC
Cell Insertion
Cell Payload
Processor
Transmit GFC
Processor
Nibble-Field
Cell Payload
Scrambler
Processor
Processor
Nibble-Field
Buffer/
Buffer/
Input Port
Scrambler
Buffer/
Buffer/
Input Port
Block
Block
Block
Block
Microprocessor
Microprocessor
Processor Block
SONET/STS-3c
To Transmit
Input Port
Interface
Interface
TxGFC
Block
Block
POH
XRT94L33
Rev.1.2.0.