PM5363 TUPP+622
TUPP+622
DATASHEET
PMC-1981421
ISSUE 4
SONET/SDH TRIBUTARY UNIT PAYLOAD PROCESSOR FOR 622 MBIT/S
INTERFACES
14
FUNCTIONAL TIMING
The timing of the TUPP+622 STM-1 input signals is illustrated in Figure 18 where
n is {1, 2, 3, 4}. This diagram shows a simple STS-3 case that outlines the
function of the various input signals associated with each of the four input buses
when the TUPP+622 is in STM-1 (STS-3) input interface mode (IHSMODEB set
high). Data on ID[7:0] (ID[15:8], ID[23:16], ID[31:24]) is sampled on the rising
edge of SCLK. The bytes forming the three STS-1 synchronous payload
envelopes are identified by the IPL[1] (IPL[2], IPL[3], IPL[4]) signal being set
high. The IC1J1[1] (IC1J1[2], IC1J1[3], IC1J1[4]) signal pulses high while IPL[1]
(IPL[2], IPL[3], IPL[4]) is low to mark the position of the first C1 byte in the STS-3
transport envelope. The IC1J1[1] (IC1J1[2], IC1J1[3], IC1J1[4]) signal is set high
for three SCLK periods while IPL[1] (IPL[2], IPL[3], IPL[4]) is also set high to
mark the J1 bytes of each STS-1 SPE. The ITMF[1] (ITMF[2], ITMF[3], ITMF[4])
signal is selectable to mark the third byte after J1 of the first tributary in an STS-1
SPE or the H4 byte in the last (fourth) frame of a tributary multiframe. In this
diagram, ITMF[1] (ITMF[2], ITMF[3], ITMF[4]) is shown to be marking the last H4
byte of the tributary multiframe in STS-1 #1 and STS-1 #3. The H4 byte in STS-1
#2, as shown, is not last in the tributary multiframe. In this simple example, all
STS-1 SPEs are aligned to the STS-3 transport envelope such that the J1 bytes
directly follow the C1 bytes and no STS-1 pointer justification events are
occurring. Other alignments are possible. The four input buses can be
independently configured to handle STS-1/AU3 or AU4 and the SPE/VC
alignments of the input buses may be different. However, the transport frame
alignments of the four input buses must be identical. That is, the C1 portion of all
the IC1J1[4:1] signals must be coincident. This diagram also applies to the AU3
mode as it is equivalent to the STS-1 mode, except for nomenclature.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
389
PMC [ PMC-SIERRA, INC ]
