PM5313 Datasheet, PDF (583/646 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
The figure above shows the STS-3c (STM-1/AU4) 19.44 MHz byte DROP bus
timing where n is {1, 2, 3, 4}. This timing applies to all four 19.44 MHz Byte
Telecom DROP buses. DCK is a 19.44 MHz clock. The frame pulse DFP marks
the first synchronous payload envelope byte on DD[7:0] (DD[31:24], DD[23:16],
DD[15:8]). It is not necessary for DFP to be present at every frame. An internal
counter fly-wheels based on the most recent DFP received. Transport overhead
and payload bytes are distinguished by the DPL[1] (DPL[4], DPL[3], DPL[2])
output which is set low to mark transport overhead bytes and set high to mark
payload bytes. The DROP bus composite timing signal DC1J1V1[1]
(DC1J1V1[4], DC1J1V1[3], DC1J1V1[2]) is set high when DPL[1] (DPL[4:2]) is
set low to mark the C1 byte. DC1J1V1[1] (DC1J1V1[4:2]) is set high when
DPL[1] (DPL[4:2]) is also set high to mark the J1 byte of the STS-3c
(STM-1/AU4) stream. Optionally, DC1J1V1[1] (DC1J1V1[4:2]) is set high once
every multiframe to mark the first frame of the DROP bus tributary multiframe.
When processing an STS-3c (STM-1/AU4) stream, the V1 pulse marks the more
significant byte of the Null Pointer Indication (NPI) of the first frame in each
tributary multiframe. The alignment of the transport frame and the synchronous
payload envelope of STS-3c (STM-1/AU4) stream shown corresponds to an
active offset of 0 and is for illustration only. Other alignments are possible. Also,
the SPE alignments of the four 19.44 MHz Byte Telecom DROP buses may be
different. The DROP bus parity output DDP[1] (DDP[4], DDP[3], DDP[2]) reports
the parity of DD[7:0] (DD[31:24], DD[23:16], DD[15:8]) and optionally includes
DPL[1] (DPL[4:2]) and DC1J1V1[1] (DC1J1V1[4:2]).
PROPRIETARY AND CONFIDENTIAL
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