Establishment And Termination Of Communications Relations - Siemens SIMATIC ET 200AL System Manual

6.10

Establishment and termination of communications relations

Establishment and termination of communications
The table below shows the establishment and termination of communications as part of open
communication.
Table 6- 5 Establishment and termination of communications
Setting up the connection
With the user program
By configuring a connec-
tion
Communication
Function Manual, 05/2021, A5E03735815-AJ
6.10 Establishment and termination of communications relations
Establishing communication
After downloading the user program to the
CPUs:
The passive communications partner sets up
the local connection access by calling
TSEND_C/TRCV_C or TCON. Calling
TSEND_C/TRCV_C or TCON on the active
partner starts connection establishment. If
the connection could be established, there is
positive feedback to the instructions in the
user program.
After you have terminated a connection
using the instruction T_RESET, the connec-
tion is reestablished.
If the connection aborts, the active partner
attempts to re-establish the connection. This
applies only if the connection was successful-
ly established beforehand with TCON.
After downloading the connection configura-
tion and the user program to the CPUs.
Open User Communication
Terminating communication
• Using the TSEND_C/TRCV_C, TDISCON and
T_RESET instructions
• When the CPU changes from RUN to STOP
mode
• With POWER OFF/POWER ON on a CPU
By deleting the connection configuration in
STEP 7 and downloading the changed con-
figuration to the CPU.
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