3170-PDP
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FLEX Platform
Glossary
FLEX I/O™ PROFIBUS Adapter
Page 136 of 152
ProSoft Technology, Inc.
August 23, 2007
multicast relationships
allow transmission of messages to a group of nodes simultaneously, but only
unconfirmed services are available.
network
a series of stations or nodes connected by some type of communication medium.
A network may consist of a single link or multiple links.
node
an address or software location on the network. Also referred to as
node
.
STATUS LED
a bicolor LED, located on the front panel of the coprocessor that indicates the
condition of the coprocessor
OD
Object Dictionary. In FMS, an OD is a database within the station, holding the
description of all explicit communication objects of that station and making them
available for control and monitoring.
open at the initiator
in FMS, a connection type where the source service access point (SAP) is
shared among several communication relationships (associated with a different
destination address and SAP). The device uses only one of these relationships at
a time, depending on the selected remote node.
open at the responder
in FMS, a connection type where the destination address and service access
point (SAP) are undefined, thus making the connection available to any device.
OPEN command
in a MSG instruction, establishes a connection between the coprocessor and a
remote node on the network
OSI
Open Systems Interconnect. A standard that provides the framework for defining
the process of communication between nodes on the PROFIBUS network.
physical layer
The first layer of the seven-layer OSI reference model. This layer is where the
coprocessor connects to the network media.
