9.4.4.4
Passive partner (server)
This program implements a simple state machine to manage the opening of a connection,
receiving a message, sending a response, and handling errors.
The flow of this state machine is to connect, then repeatedly receive a message and send a
response. If the connection is dropped, the state machine reopens the passive connection.
Refer to the "Passive partner symbol table" (Page 544) to see the symbol table for this
program.
Network 1: On the first scan....
Initialize the State variable to initiate a connection.
Network 2: Process the state machine...
Determine the current state of the state machine and jump to the label for the state handler.
If the state is ever illegal, the CPU goes to the STOP mode.
Network 3: State Connect...
S7-200 SMART
System Manual, V2.3, 07/2017, A5E03822230-AF
9.4 Open user communication library
Libraries
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