Assembly Object; Attribute Semantics - Allen-Bradley 1444-TSCX02-02RB User Manual

Assembly Object

The Assembly Object (class code 0x04) binds attributes of multiple objects,
which allows data to or from each object to be sent or received over one
connection.
Assembly Objects can be used to bind input data or output data. I/O data
connections are established between an Originator (O) and a Target (T) where
in this case, O is the controller and T is this module. Output data is sent in the
O-T direction and Input data is sent in the T-O direction. The input data
assembly therefore comprises measurements that are made by the module while
the output data assembly is used for control data being sent to the module.
Table 269 - Object Instances
Instance ID Description
0 Class Instance for the Assembly Object
100 Instance 1 defines one, input data assembly option (O- T)
101 Instance 2 defines one, output data assembly option (T - O)
Table 270 - Class Attributes
Attribute Access NV
ID Rule
1 Get NV
2 Get V
Table 271 - Instance Attributes
Attribute Access Rule NV Name
ID
3 Get -
4 Get V

Attribute Semantics

Member List
See I/O Message Formats.
IMPORTANT Set access for Output data is not allowed as a security measure to help
prevent disruption of controlled modules.
Common Services
Service Implementation
Code
Class Instance
0x0E x x
Rockwell Automation Publication 1444-UM001D-EN-P - June 2018
Name Data Description of Attribute
Type
Revision UINT Defines the current revision of
the Assembly Object
Maximum UINT
Instance
Data Type Description of Attribute
Data STRUCT The input or output data
Size UINT The assembly (data) size
Service Name Description of Service
Get Attribute Single Returns the contents of the specified
attribute
CIP Objects Appendix A
Semantics of
Values
Current: 2
101
Semantics of
Values
-
Number of bytes
517