Updates to Arguments Following Parameter Edits

If you edit an Add-On Instruction by adding, deleting, renaming, reordering, or changing the status or usage type of one or more parameters, RSLogix 5000 software, version 18 and later, automatically updates the arguments on calls to the instruction.

A confirmation dialog box shows you the impacts of the edits and lets you review the pending changes before confirming or rejecting them.


· An asterisk identifies parameters with changes pending.
· Existing arguments are reset to the parameters they were originally associated with.
· Newly added parameters are inserted with a ? in the argument field, except for Structured Text, where the field is blank.
· Unknown parameters are created for arguments where associated parameters have been deleted.

To accomplish this update, the Logix Designer application tracks the changes made to the Add-On Instruction parameters from the original instruction to the final version. In contrast, the import and paste processes compare only parameter names to associate arguments with parameters. Therefore, if two different parameters have the same name, but different operational definitions, importing or pasting may impact the behavior of the instruction.