Omron NX Series User Manual

10-2-5
Request Path (IOI)
A request path indicates an object of a device on the network.
A CIP communications instruction uses the request path to access an object of a device.
Overview of Request Path
In the CIP world, each device is modeled as a collection of objects. An Object abstractly represents
the specific configuration elements of a device.
Object Instance
D
ata
Data
Data
Data
Processing
Attributes
Service
External request
(example: read)
Device
Object
Object
Object
In the CIP Common Specification, Object, Class, Instance, Attribute, and Service are defined as fol-
lows: (Source: CIP Common Specification)
Term Definition
Object An abstract representation of a particular component within a device.
Class A set of objects that all represent the same kind of system component.
Instance A specific and real (physical) occurrence of an object.
Attribute A description of an externally visible characteristic or feature of an object.
Service A request from an external object (e.g., to read data).
You use the Class ID Instance ID and Attribute ID to access an object.
You specify these three IDs to designate an object in a device.
When you make a request from an external device for a service, you must specify the Class ID In-
stance ID and Attribute ID. (The Instance ID and Attribute ID are not required for some services.)
.....
Example: Reading the Name of a Device
(Identity Object Class ID = 1)
Service Request
Get_Attribute_
Single
Destination
Class: 1
Instance: 1
Attribute: 7
Response
Product Name
Instance ID = 1
Attribute = 7
Device
Class ID = 1
I
nstance ID = 1
Attribute 7
Attribute 6
Attribute 1
Class ID = 2
10 CIP Message Communications
10-13
NX-series EtherNet/IP Unit User's Manual (W627)
10-2 Client Function of CIP Mes-
sage Communications
10
10-2-5 Request Path (IOI)

Omron NX Series Specifications

General

Brand	Omron
Model	NX Series
Category	Controller
Language	English