Specifications

Introduction
31004624 8/2009 15
Preferred Modules
An island bus can also support those auto-addressable modules referred to as
preferred modules. Preferred modules do not mount in segments, but they do count
as part of the 32-module maximum system limit.
A preferred module can connect to an island bus segment through an
STB XBE 1100 EOS module and a length of STB XCA 100x bus extension cable.
Each preferred module has two IEEE 1394-style cable connectors, one to receive
the island bus signals and the other to transmit them to the next module in the series.
Preferred modules are also equipped with termination, which must be enabled if a
preferred module is the last device on the island bus and must be disabled if other
modules follow the preferred device on the island bus.
Preferred modules can be chained to one another in a series, or they can connect
to Advantys STB segments. As shown in the following figure, a preferred module
passes the island bus communications signal from the primary segment to an
extension segment of Advantys STB I/O modules:
1 primary segment
2 NIM
3 STB XBE 1100 EOS bus extension module
4 1 m length STB XCA 1002 bus extension cable
5 preferred module
6 1 m length STB XCA 1002 bus extension cable
7 extension segment of Advantys STB I/O modules
8 STB XBE 1300 BOS bus extension module for the extension segment
9 STB XMP 1100 termination plate