Installation and Operation Manual
X-DPT-DeviceNet-SLA5800-SLAMf-Series-RevB-PC-eng
Part Number: 541B200AAG
March, 2015
100
Section 8 - Glossary
Brooks DeviceNet PCs
Connection
A connection is a logical link between two devices by which messages are
transferred. A device can have 1 or more simultaneous Connections. In most
typical applications, data is exchanged using 1 Explicit Connection and 1 I/O
Connection. The DeviceNet specification has defined a pre-configured set of
Connections referred to as the Master/Slave (M/S) Connection Set.
Device Profile
A specification that defines a set of DeviceNet objects that uniquely
represents a particular device of that type or class. The device profile can
further define attributes, services, assemblies, etc. that a device must
support to be considered part of that type or class of device. These profiles
are found in the ODVA specification, Vol. 2. The SLA5800/SLAMf Series
PC/PM conforms to the vendor-specific device profile.
EDS
The Electronic Data Sheet (EDS) is a specially formatted text description for
a device that describes the I/O characteristics and configurable parameters
that are accessible via the DeviceNet network. EDS files can be read by
configuration software used to configure DeviceNet networks (ex: RsNetworx
from Allen-Bradley)
EPATH (formerly known as PATH)
An EPATH is a unique identifier (sometimes referred to as a pointer)
comprised of a Class ID, an Instance ID, and an Attribute ID. Some Classes
have EPATH attributes that point to a particular data item. An example of this
would be the Connection Class that contains two attributes, Produce Path
and Consume Path. These attributes define where incoming data is sent to,
and outgoing data comes from. I/O Connections make use of these two
particular attributes.
Expected Packet Rate (EPR)
The EPR is an attribute in the Connection Class that defines the maximum
amount of time (in msec) messages should be received by the Connection
(implementation of this value is dependent upon the Connection type, Explicit
or I/O, but the behavior is the same in all Connection types). If the time
between received messages for that connection exceeds the EPR, the
Connection times out. This may result in the Connection being released by
the device.