XRT79L71_1 Datasheet, PDF (74/434 Pages) Exar Corporation – 1-CHANNEL DS3/E3 ATM UNI/PPP/CLEAR-CHANNEL FRAMER IC -

XRT79L71
1-CHANNEL DS3/E3 ATM UNI/PPP/CLEAR-CHANNEL FRAMER IC - REGISTER/MAP DESCRIPTION
REV. 1.0.0
BIT NUMBER
NAME
5
Internal LOS Enable
4
RESET
3
Direct Map ATM
TYPE
R/W
R/W
R/W
DESCRIPTION
Internal LOS Enable:
This READ/WRITE bit-field permits the user to enable or disable
the Internal LOS Detector, within the Receive DS3/E3 Framer
block. If the user disables the Internal LOS Detector then the
Receive Section of the XRT79L71 will only declare the LOS
defect condition, whenever the Receive DS3/E3 LIU block
declares the LOS defect condition.
0 - Internal LOS Detector is disabled.
1 - Internal LOS Detector is enabled.
Software RESET Input:
A "0" to "1" transition in this bit-field commands a Software
RESET to the XRT79L71. Once the user executes a Software
reset to the frame, all of the internal state machines will be reset
and the Receive DS3/E3 Framer block will execute a Reframe
operation.
NOTE: For a Software Reset, the contents of the Command
Register will not be reset to their default values.
Direct Map ATM:
This READ/WRITE bit-field permits the user to configure the
XRT79L71 to operate in either the Direct Map ATM mode or in
the PLCP Mode. If the user configures the XRT79L71 to operate
in the Direct Map ATM Mode, then both the Transmit PLCP Pro-
cessor and the Receive PLCP Processor blocks will be
bypassed and will not process any ATM cell traffic. In this case,
ATM cells will be DIRECTlY mapped into the payload bits within
each outbound DS3 or E3 frame, without first being mapped into
PLCP frames.
If the user configures the XRT79L71 to operate in the Direct Map
ATM Mode, then both the Transmit PLCP Processor and
Receive PLCP Processor blocks will be enabled and will be pro-
cessing ATM cell traffic.
0 - Configures the XRT79L71 to operate in the PLCP Mode.
1 - Configures the XRT79L71 to operate in the Direct Map ATM
Mode.
NOTE: This bit-field is only active if the XRT79L71 has been
configured to operate in the ATM UNI Mode.
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