Chapter 14 Message Communication Support Commands - Mitsubishi Electric MELSEC iQ-R Series User Manual

14
MESSAGE COMMUNICATION SUPPORT
COMMANDS
This chapter describes the objects and services of the commands used for the message communication function (client).
EtherNet/IP devices are provided with objects (functions or data expressed abstractly) and services (operations or functions
to be executed by requests).
Explanation of terms
Term Description
Object Each object is managed with its class ID inside an EtherNet/IP device.
An object has one or more instances.
Instance Each instance is managed with its instance ID inside an object.
An instance has one or more pieces of information called an attribute inside.
In addition, an instance has one or more services that can be executed and each service can be used with its service code.
Available services are determined by the instance.
Attribute Each attribute is managed with its attribute ID inside an instance.
The following shows the relationships between objects, instances, and attributes.
Object (class ID: 01H)
Instance (ID: 01)
Attribute (ID: 01H)
Attribute (ID: 02H)
Instance (ID: 02)
Attribute (ID: 01H)
Attribute (ID: 02H)
Object (class ID: 02H)
Instance (ID: 01)
Attribute (ID: 01H)
Attribute (ID: 02H)
14 MESSAGE COMMUNICATION SUPPORT COMMANDS
Instance (ID: 02)
Attribute (ID: 01H)
Attribute (ID: 02H)
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