Using Connection Parameter Assignment; Creating And Configuring Connections - Siemens SIMATIC ET 200AL System Manual

The structure mapped in the read list matches, both in the order and in the assigned data
types, the corresponding nodes of the node set file.
If the structure now changes on the server, for example tagA and tagB are swapped, and the
read list remains the same in the client, the assignment is no longer correct:
• The total length of the data remains the same (only the order has changed)
• The configuration of the structure is different for client and server!
No error message in the case of different structure configuration between client and
server
If the structures of client and server do not match, this rule violation will possibly not
generate any error during compilation and also not in runtime.
Make sure not to change the configured assignments for structures in runtime. If required,
reconfigure the assignment in the read and write lists!
9.4.9

Using connection parameter assignment

9.4.9.1

Creating and configuring connections

With the instructions for OPC UA clients, you create a user program that exchanges data with
an OPC UA server. A series of system data types are required for this.
To simplify your work with these system data types, a connection parameter assignment for
OPC UA clients is available starting in STEP 7 (TIA Portal) Version 15.1.
Use of the connection parameter assignment is optional and not mandatory. You can also
manually create the required system data types.
We use an example to make the description easier to follow, see description of the example
(Page 320).
Communication
Function Manual, 05/2021, A5E03735815-AJ
WARNING
9.4 Using the S7-1500 CPU as an OPC UA client
OPC UA communication
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