PM5350-1 Datasheet, PDF (43/196 Pages) PMC-Sierra, Inc – SATURN USER NETWORK INTERFACE

DATA SHEET
PMC-960924
ISSUE 5
PM5350 S/UNI-ULTRA
SATURN USER NETWORK INTERFACE
The Error Monitor Block accumulates these line layer bit errors in a 20 bit
saturating counter that can be read via the microprocessor interface. During a
read, the counter value is latched and the counter is reset to 0 (or 1, if there is an
outstanding event). Note, this counter should be polled at least once per second
to avoid saturation which in turn may result in missed bit error events.
The Error Monitor Block also accumulates line far end block error indications
(contained in the M0/M1 byte) in a similar manner.
7.6 Receive Path Overhead Processor
The Receive Path Overhead Processor (RPOP) provides pointer interpretation,
extraction of path overhead, extraction of the synchronous payload envelope,
and path level alarm and performance monitoring.
7.6.1 Pointer Interpreter
The Pointer Interpreter interprets the incoming pointer (H1, H2) as specified in
the references. The pointer value is used to determine the location of the path
overhead (the J1 byte) in the incoming STS–3c (AU4) or STS–1 (AU3) stream.
The Pointer Interpreter Block detects loss of pointer (LOP) in the incoming STS–
1 or STS–3c. LOP is declared as a result of eight consecutive invalid pointers or
eight consecutive NDF enabled indications. LOP is removed when the same
valid pointer with normal NDF is detected for three consecutive frames.
The Pointer Interpreter Block detects path AIS in the incoming STS–1 or STS–3c
stream. PAIS is declared on entry to the AIS_state after three consecutive AIS
indications. PAIS is removed when the same valid pointer with normal NDF is
detected for three consecutive frames or when a valid with NDF enabled is
detected.
The pointer value is used to extract the path overhead from the incoming stream.
Note that due to anomalies in the standard pointer interpretation rules, certain
illegal pointers may not cause the device to declare a loss of pointer (LOP) state.
In this situation, however, the device will declare a loss of cell delineation state
and return to normal operation when presented with legal pointer values. Such
illegal pointers typically can only be generated continuously by test equipment
and will not normally occur during live-traffic operation.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE 31