PM5342 Datasheet, PDF (472/558 Pages) PMC-Sierra, Inc – SONET/SDH Payload Extractor/Aligner

DATA SHEET
PMC-970133
ISSUE 4
PM5342 SPECTRA-155
SONET/SDH PAYLOAD EXTRACTOR/ALIGNER
Figure 40 - Transport Overhead Extraction (STS-3/3c)
RTOHFP
RTOHCLK
••••
••••
A1 byte A1 byte A1 byte A2 byte A2 byte
E2 byte E2 byte
(unused) (unused)
••••
RTOHCLK
RTOHFP
A1 byte
A1 byte
RTOH
B7 B8
B1 B2 B3 B4 B5 B6 B7 B8
B1 B2 B3 B4 B5 B6 B7 B8
The transport overhead extraction timing diagram above illustrates the transport
overhead extraction interface for STS-3/3c (STM-1/AU3/AU4). The transport
overhead extraction clock, RTOHCLK is nominally a 5.184 MHz clock (1.728
MHz for an STS-1 (STM-0/AU3) stream), and is derived from the receive line
clock, RCLK. The entire transport overhead (the complete 9 row by 9 column
structure) is extracted for the STS-3/3c (STM-1/AU3/AU4) stream and is
serialized on RTOH over a frame period (125 µs). For STS-1 (STM-0/AU3), the
transport overhead structure of 9 rows by 3 columns is serialized in a similar way
on RTOH over a frame period (125 µs).
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE 450