I-7242D user manual
I-7242D DeviceNet/Modbus RTU Gateway User’s Manual, July 2006, Version 1.1 32/124
4 DeviceNet Profile Area
This chapter is for users who want to understand more detailed information
related to the I-7242D device when using the DeviceNet protocol. This section
documents the detailed functions for each object class that is implemented in
the DeviceNet network
4.1
Introduction to the DeviceNet Objects of I-7242D
The I-7242D has been developed in accordance with the
Object
Modeling
from the DeviceNet protocol. This model leads to a method used for
addressing the I-7242D’s data made up of four separate values: MAC ID
、
Class ID
、
Instance ID and Attribute ID. An address made up in this way is
known as a “
Path
”. The Connection by Explicit Messaging, for example, uses
paths of this sort to exchange data from one node to another on a DeviceNet
network. See table 4-1 to know the address field of I-7242D.
Table 4-1 Address field of I-7242D
Address
Min. - Max.
Description
Node 0-63
This field allows you to address one subscriber out of the series of
subscribers on a DeviceNet network using its
MAC ID
.
Class 1-65535
All objects sharing the same characteristics belong to the same class,
characterized by its
Class ID
.
Instance 0-65535
All instances from one class share the same
attributes
but each of
them has its own set of values for these attributes.
Attribute 1-255
It is assigned some sort of value (byte, unsigned integer, character
string, etc.) in order to supply information about the subscriber’s status
or to make settings on the subscriber’s behaviors
