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OPC UA communication
9.3 Using the S7-1500 as an OPC UA server
Communication
Function Manual, 11/2019, A5E03735815-AH
229
Integrating the server method
The diagram below shows how an OPC UA client (A) calls the server method "Cool":
The CPU executes the instance "Cool1" of the server method "Cool" in the cyclic user
program
⑥
.
The CPU first uses the instruction "OPC_UA_ServerMethodPre" to query
④
whether an
OPC UA client has called the server method "Cool"
①
.
●
If the server method has not been called, program execution returns directly to the cyclic
user program over
④
and
⑥
. The CPU resumes the cyclic user program after "Cool1".
●
If the server method has been called, this information is returned to the server method
"Cool" over
④
. The actual functionality is now executed in the Cool server method,
see"<Method Functionality>" in the graphic.
The server method then uses the instruction "OPC_UA_ServerMethodPost"
⑤
to notify
the firmware (B) that the instruction has been executed
③
.
The firmware returns this information over
②
to the calling OPC UA client (A).
Summary of Contents for SIMATIC ET 200SP
Page 1: ...Communication ...