PM5363 TUPP+622
TUPP+622
DATASHEET
PMC-1981421
ISSUE 4
SONET/SDH TRIBUTARY UNIT PAYLOAD PROCESSOR FOR 622 MBIT/S
INTERFACES
The input bus demultiplexer also provides timing signals for the other blocks
within the STP. Frame alignment signals for the incoming data stream, IC1J1,
ITMF, IPL, ITV5 and ITPL are sampled, buffered and distributed to the associated
tributary payload processors (VTPPs). In order to have synchronous operation of
the VTPPs with a single clock, the incoming data and control signals may be
delayed by a number of system clock cycles before distribution to the VTPPs.
The delay is used to align the incoming data with the outgoing data at each
VTPP. The amount of delay is adjusted such that the separation of the incoming
STS/AU frame and the outgoing frame at each VTPP appears to be in multiples
of three SCLK or twelve HSCLK periods.
When configured for AU4 mode, the input bus demultiplexer provides the
necessary timing coordination between the three tributary payload processors in
the STP. The single J1 byte marker input on IC1J1 is retimed and distributed to
each of the three tributary payload processors in the STP. The tributary
multiframe detected by VTPP #1 is distributed to the two other VTPPs, as VTPP
#1 is the only one receiving a valid H4 byte within the STP.
10.2 Output Bus Multiplexer
The first stage of the output bus multiplexer is formed by the output multiplexing
logic of each STP. It gathers payload data from the three tributary payload
processors within the STP and multiplexes this data into an STM-1 (STS-3)
payload data stream. It also multiplexes signals from each tributary payload
processor that mark tributary SPEs and tributary V5 bytes into the respective
STM-1 (STS-3) signals. The extracted tributary path overhead serial signals
(POH[12:1], POHFP[12:1], POHEN[12:1], POHCK and RAD[4:1]) are buffered by
this stage of the output bus multiplexer block.
The output bus multiplexer also provides timing signals for other blocks within an
STP. Frame alignment signal for the outgoing data stream, OTMF, is sampled,
buffered and distributed to the tributary payload processors (VTPPs), tributary
path overhead processors (RTOPs) and tributary trace buffers (RTTBs) of the
STP. The output bus multiplexer contains a four frame counter that will flywheel in
the absence of an active OTMF input, internally generating tributary multiframe
timing for the outgoing STM-1 data stream. The output bus multiplexer will
internally generate J1 and SPE timing for the outgoing STM-1 data stream at the
STS-1 (AU3) or AU4 level. The transport and payload frame boundaries are
reported on the corresponding OC1J1V1 and OPL outputs. This timing drives the
outputs of the three VTPPs, RTOPs and RTTBs within the STP.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
90
PMC [ PMC-SIERRA, INC ]
