Installation guide

Glossary
890USE17100 September 2003 111
preferred module An I/O module that functions as an auto-addressable node on an Advantys STB
island but is not in the same form factor as a standard Advantys STB I/O module and
therefore does not fit in an I/O base. A preferred device connects to the island bus
via an STB XBE 1000 EOS module and a length of STB XCA 100x bus extension
cable. It can be extended to another preferred module or back into a standard island
segment. If it is the last device on the island, it must be terminated with a 120 Ω
terminator.
premium
network
interface
An Advantys STB network interface module designed at a relatively high cost to
support high module densities, high transport data capacity (e.g., for web servers),
and more diagnostics on the island bus.
prioritization Prioritization is an optional feature that allows you to selectively identify digital input
modules to be scanned more frequently during the NIM’s logic scan of the island
bus.
process I/O An Advantys STB I/O module designed for operation at extended temperature
ranges in conformance with IEC type 2 thresholds. Modules of this type often feature
high levels of on-board diagnostics, high resolution, user-configurable parameter
options, and higher levels of agency approval.
process image A part of the NIM firmware that serves as a real-time data area for the data exchange
process. The process image includes an input buffer that contains current data and
status information from the island bus and an output buffer that contains the current
outputs for the island bus, from the fieldbus master.
producer/
consumer model
In networks that observe the producer/consumer model, data packets are identified
according to their data content rather than by their physical location. All nodes
"listen" on the network and consume those data packets that have appropriate
identifiers.
Profibus DP Profibus Decentralized Peripheral. An open bus system that uses an electrical
network based on a shielded two-wire line or an optical network based on a fiber-
optic cable. DP transmission allows for high-speed, cyclic exchange of data between
the controller CPU and the distributed I/O devices.
reflex action The execution of a simple, logical command function configured locally at an island
bus I/O module. Reflex actions are executed by island bus modules on data from
various island locations, like input and output modules or the NIM. Examples of
reflex actions include compare and copy operations.
R