PM5313 Datasheet, PDF (573/646 Pages) PMC-Sierra, Inc – SONET/SDH Payload Extractor/Aligner for 622 Mbit/s Interfaces

PRODUCTION
DATASHEET
PMC-1981162
ISSUE 6
PMC-Sierra, Inc.
PM5313 SPECTRA-622
SONET/SDH PAYLOAD EXTRACTOR/ALIGNER FOR 622 MBIT/S
actual arrival rate of the receive path overhead bytes. This allows the use of over-
sampling to multiplex the path overhead data streams from the RPOP’s onto a
single RPOH output. The entire path overhead (J1, B3, C2, G1, F2, H4, Z3, Z4,
Z5 bytes) of each STS-1 (STM-0/AU3) in an STS-12 (STM-4/AU3) receive
stream can be extracted, serialized and placed on RPOH over one or two RPOH
frame periods. For each byte, the most significant bit (msb) is transmitted first.
RPOHFP marks the most significant bit of the first J1 byte of the STS-12 (STM-
4/AU3). This corresponds to the msb of the J1 byte of STS-3 (STM-1) #1 STS-1
(STM-0/AU3) #1 stream. The RPOHEN indicates the validity of the path
overhead bytes extracted to the RPOH. If a new path overhead byte of a
particular STS-1 (STM-0/AU3) stream is not available during the current time-slot
then the RPOHEN is set low. In the above example, the J1 byte of the STS-3
(STM-1) #1 STS-1 (STM-0/AU3) #1 stream is valid but the B3 byte is not yet
available in the current RPOH frame.
The path overhead data streams of corresponding STS-1 (STM-0/AU3) or
equivalent receive streams are arranged in the order of the Receive Path
Processing Slice numbers (RPPS #1 to RPPS #12). RPPS #1 to #12 always
process the SONET/SDH bytes (i.e. STS-1 (STM-0/AU3) streams) in the
received order.. With this assignment, the path overhead data streams are driven
on to RPOH in the hierarchical order of STS-3 #1 STS-1 #1, STS-3 #2 STS-1 #1,
STS-3 #3 STS-1 #1 - #3) STS-3 #4 STS-1 #1 and etc.
For an STS-3c (STM-1/AU4) in the STS-12 (STM-4/AU3/AU4) receive stream,
only the path overhead time-slots associated with the equivalent STS-1 (STM-
0/AU3) #1 (processed by a master RPPS) carry valid path overhead bytes when
RPOHEN is set high. During the path overhead time-slots of the equivalent STS-
1 (STM-0/AU3) #2 and #3 processed by corresponding slave RPPS’s, RPOHEN
is always set low. For an STS-12c (STM-4-4c) receive stream, only the path
overhead time-slots associated with the equivalent STS-3 (STM-1) #1 STS-1
(STM-0/AU3) #1 (processed by the master RPPS #1) carry valid path overhead
bytes when RPOHEN is set high. RPOHEN is always set low for the eleven
remaining STS-1 (STM-0/AU3) equivalent streams processed by corresponding
slave RPPS’s.
B3E identifies the bits within the B3 bytes containing a parity error and it is only
valid during the B3 byte time-slot of an STS-1 (STM-0/AU3) or equivalent stream
when RPOHEN is set high.
RALM identifies an STS-1 (STM-0/AU3) or equivalent stream where one or more
receive alarm conditions have been detected. The receive alarm conditions which
enable an assertion during the corresponding RALM time-slot are controlled by
the SPECTRA-622 RPPS RALM Output Control #1 and #2 registers. RALM for
each STS-1 (STM-0/AU3) or equivalent stream is asserted during the entire
PROPRIETARY AND CONFIDENTIAL
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