Avaya Definity SI Maintenance Manual page 209

Duplicated Hardware
Processor Interface Circuit Pack(s) (TN765)
Duplication Interface Circuit Pack (TN772)
Duplication Interface Circuit Pack
The Duplication Interface circuit pack is required to support SPE duplication.
Duplication Interface A is part of the SPE in the A control carrier, and Duplication
Interface B is part of the SPE in the B control carrier.
The Duplication Interface circuit packs provide a broad range of functionality.
Alone, Duplication Interface A provides control of the following components: the
duplicated Processor circuit packs, the duplicated Tone-Clock circuit packs, the
environmental maintenance monitoring and control, and G3MT terminal
connection. Together, Duplication Interface A and Duplication Interface B provide
memory shadowing from Active SPE Memory to Standby SPE Memory and
communication between software on the Active SPE and the Standby SPE.
Duplication Interface A controls a lead that indicates to the duplicated Processor
and Network Control circuit packs, respectively, which SPE is currently the Active
SPE. This lead is known as the SPE Select lead. Duplication Interface A controls
another set of leads that indicate to the duplicated TN768 and TN780 8
Tone-Clock circuit packs which of the two is currently the active one. These leads
are known as the Tone-Clock Select leads. System software can request that the
SPE Select lead and/or the Tone-Clock Select leads be changed. Duplication
Interface A controls and monitors in the PPN of a High or Critical Reliability
system the same set of environmental leads that the EPN TN775 or TN775B
Maintenance circuit pack controls and monitors in an EPN.
The Duplication Interface circuit packs communicate with one another over the
Inter-Carrier Cable (ICC). In a multicarrier cabinet, the ICC physically consists of
two 25-pin connector cables known as ICC-A and ICC-B. In a single-carrier
cabinet, the ICC physically consists of three 25-pin connector cables known as
ICC-A, ICC-B, and ICC-C. The ICC connects the Duplication Interface circuit
packs via pin fields on the backplane. The pin fields where ICC-A and ICC-B (and
ICC-C in a single-carrier cabinet) are connected are labeled on the backplane
near the pin fields for the Duplication Interface circuit packs. The ICC carries
leads related to maintaining a High or Critical Reliability system. Furthermore,
without the ICC properly attached, the system cannot function as either a High or
Critical Reliability system or as a Standard system.
555-233-123
NOTE:
There may be zero, one, or two Processor Interface circuit pack.
However, both SPEs must have an equal number of Processor
Interface circuit packs.
Issue 4 May 2002 6-5