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PRELIMINARY
XRT79L71
154
REV. P2.0.0
1-CHANNEL DS3/E3 CLEAR-CHANNEL FRAMERLIU COMBO - CC/HDLC ARCHITECTURE
The purpose of the Transmit DS3/E3 LIU Block is to accept a DS3/E3 data-stream from the Transmit DS3/E3
Framer block and to perform all of the following operations on this data.
To convert this outbound data into the B3ZS line code (for DS3 applications) or into the HDB3 line code (for
E3 applications)
For DS3 Applications, to further convert this data into a DS3 line signal such that each pulse that is
generated by the Transmit DS3 LIU block will comply with the Isolated Pulse Template requirements per
Bellcore GR-499-CORE
For E3 Applications, to further convert this data into an E3 line signal such that each pulse that is generated
by the Transmit E3 LIU block will comply with the ITU-T G.703 Pulse Template requirements for E3
applications.
This particular section will describe the functionality and configuration options of the Transmit DS3/E3 LIU
Block for DS3 applications. The functionality and configuration options of the Transmit DS3/E3 LIU Block for
Figure 68 presents a more detailed illustration of the Transmit DS3/E3 LIU Block within the XRT79L71.
Figure 68 indicates that the Transmit DS3/E3 LIU Block consists of the following functional blocks.
The B3ZS Encoder Block
The Jitter Attenuator Block (which can be configured to operate in either the Transmit or Receive Directions)
The Timing Control Block
The Transmit Pulse Shaping Block
FIGURE 68. ILLUSTRATION OF THE TRANSMIT DS3/E3 LIU BLOCK WITHIN THE XRT79L71
B3ZS
Encoder
Block
B3ZS
Encoder
Block
Jitter
Attenuator
Block
Jitter
Attenuator
Block
Timing
Control
Block
Timing
Control
Block
Transmit
Pulse
Shaping
Block
Transmit
Pulse
Shaping
Block
Transmit
Drive
Monitor
Block
Transmit
Drive
Monitor
Block
Line
Driver
Transmit
Control
Block
Transmit
Control
Block
MUX
From Transmit DS3/E3
Framer Block
TxLEV
TxON
LIU Remote Loop-back
Path
TTIP
TRING
DMO
MTIP
MRING
Internal Tx
Monitoring
NOTE: Jitter Attenuator Block
Can be configured to operate in Transmit
Or Receive Path
TAOS