PM5366 datasheet(204/267 Pages) PMC

204 / 267 page

PRELIMINARY

PM5366 TEMAP-84

DATASHEET

PMC-2010672

ISSUE 1

HIGH DENSITY 84/63 CHANNEL VT/TU MAPPER

AND M13 MULTIPLEXER

PROPRIETARY AND CONFIDENTIAL

192

Unused

Transparent VT2/TU12 Mapping

VT2 and TU12 virtual tributaries, TVT2s, are transported across the SBI bus in a

similar manner to the E1 tributary mapping. The TEMAP-84 supports both TVT

modes simultaneously in the SBI DROP bus and is configurable on a per

tributary basis in the SBI ADD bus.

Table 37 shows the transparent structure where “I” is used to indicate information

bytes. There are two options when carrying virtual tributaries on the SBI bus, the

primary difference being how the floating V5 payload is located.

The first option is locked TVT mode which carries the entire VT2/TU12 virtual

tributary indicated by the shaded region in Table 37. The term locked is used to

indicate that the location of the V1,V2 pointer is locked. The virtual tributary must

have a valid V1,V2 pointer to locate the V5 payload. In this mode the V5

indicator and payload signals, SDV5, SAV5, SDPL and SAPL, are optionally

generated but must be ignored by the receiving device. In locked mode timing is

always sourced by the transmitting side, therefore justification requests are not

used and the SAJUST_REQ signal is ignored. Other than the V1 and V2 octets

which are carrying valid pointers, all octets can carry data in any format. The

location of the V1,V2,V3 and V4 octets is fixed to the locations shown in Table

37.

The second option is floating TVT mode which carries the payload comprised of

the V5 and I octets within the shaded region of Table 37. In this mode the V1,V2

pointers are still in a fixed location and may be valid but are ignored by the

receiving device. The V5 indicator and payload signals, SDV5, SAV5, SDPL and

SAPL, must be valid and are used to locate the floating payload. The justification

PM5366 Datasheet(PDF) 204 Page - PMC-Sierra, Inc