Rockwell Automation AADvance Controller Configuration Guide - Manual (Page 180)

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8-10 Document: 553633
ICSTT-RM405f-EN-P
Issue 07
Configuration Guide (AADvance Controller)
Obtaining the Connection Status for a Consumed Variable
Your application can obtain the connection status for a consumed variable. To do this,
make sure that the variable is a member of a structure data type that has two
elements: a first element of the type CONNECTION_STATUS and a second
element to match the data type of the variable. Suitable pre-defined structures do not
exist within the AADvance Workbench, but you can create them.
The CONNECTION_STATUS type is itself a structure comprising two BOOL
elements, RunMode and ConnectionFaulted. When the structure data type for a
variable includes CONNECTION_STATUS as its first element then these fields will
be automatically filled in by the AADvance controller, ready for your application to
read them.
Note: The RunMode bit in the CONNECTION_STATUS is always set to TRUE
as the AADvance controller cannot determine the actual run mode
If the connection fails, the value of the consumption variable remains at its last received
value; you cannot define an 'error' value to revert to if the communications link fails.
Example
As an example, consider the consumer of a remote variable named 'T' that is a DINT.
The variable will be named 'T' to match.
You have to define a structure data type of the form
 CONNECTION_STATUS (the connection status information)
 DINT (the value of the data)
Give the structure data type a name, suitable for re-use within the project, such as
TDINT_with_Status:
When you create the variable 'T' in the Dictionary, declare its type to be
DINT_with_Status: