
27
x r
PRELIMINARY
E3 UNI FOR ATM
XRT7234
REV. P1.0.0
58
86
RLOS
I
Receive LOS (Loss of Signal) Indicator Input (from XR-T7295E E3
Line Receiver).
This input pin is intended to be connected to the RLOS (Receive Loss of
Signal) output pin of the XR-T7295E E3 Line Receiver IC. The user can
monitor the state of this pin by reading the state of Bit 0 (RLOS) within
the Line Interface Scan Register (Address = 85h).
If this input pin is “l(fā)ow”, then it means that the XR-T7295E device is
detecting a sufficient amount of signal energy on the line, due to the
incoming E3 data-stream. However, if this input pin is “high”, then it
means that the XR-T7295E device is not detecting a sufficient amount of
signal energy on the line, due to the incoming E3 data-stream, and may
be experiencing a “Loss of Signal” condition.
For more information on the operation of the XR-T7295E E3 Line
Receiver IC, please consult the “XR-T7295E E3 Integrated Line
Receiver” data sheet.
Note:
Asserting the RLOS input pin will cause the XR-T7234 E3 UNI device
to declare an “LOS (Loss of Signal) condition. Therefore, this input pin
should not be used as a general purpose input.
59
87
NC
****
Not Bonded Out
88
RxLOS
O
Receive E3 Framer—Loss of Signal Output Indicator:
This pin is asserted
when the Receive E3 Framer encounters a string of 32 consecutive 0’s
via the RxPOS and RxNEG pins. This pin will be negated once the
Receive E3 Framer has detected a string of 32 consecutive bits, that
does not contain a string of 4 consecutive “0s”.
60
89
RxOH
O
Receive E3 Frame Overhead Bit Serial Output pin:
This output pin,
along with RxOHClk and RxOHFrame, combine to form the “Receive E3
Framer OH Byte” Serial output port. The UNI Receive E3 Framer will extract
the overhead bytes from the incoming E3 signal, and serially output these
bytes on this output pin on the rising edge of the RxOHClk output signal.
90
RxOOF
O
Receiver E3 Framer—“Out of Frame” Indicator:
The UNI Receive E3
Framer will assert this output signal whenever it has declared an “Out of
Frame” (OOF) condition with the incoming E3 frames. This signal is negated
when the framer correctly locates the FA1 and FA2 frame alignment
bytes and regains synchronization with the E3 frame.
61
91
GND
***
Ground Signal Pin
92
RxAIS
O
Receive “Alarm Indication Signal” Output pin:
The UNI will assert
this pin to indicate that the Alarm Indication Signal (AIS) has been identi-
fied in the Receive E3 data stream. The Receive E3 Framer will declare
an AIS condition, if it detects two consecutive E3 frames, each contain-
ing 7 or less “0s”.
PIN DESCRIPTION (CONTINUED)
Pin
No.
100 Pin Package
Pin No. 160
PinPackage
Symbol
Type
Description