Siemens SIMATIC ET 200AL - Establishment and Termination of Communications Relations

Open User Communication
6.10 Establishment and termination of communications relations
Communication
92 Function Manual, 12/2017, A5E03735815-AF
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
Establishing communication
Terminating communication
With the user program
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 connection is reestab-
lished.
If the connection aborts, the active partner attempts
to re-establish the connection. This applies only if
the connection was successfully established before-
hand with TCON.
• Using the TSEND_C/TRCV_C,
TDISCON and T_RESET instruc-
tions
• When the CPU changes from
RUN to STOP mode
• With POWER OFF/POWER ON
on a CPU
By configuring a connection
After downloading the connection configuration and
the user program to the CPUs.
By deleting the connection configura-
tion in STEP 7 and downloading the
changed configuration to the CPU.