Acknowledgment; Connection Establishment - Siemens CP 1243-7 LTE Operating Instructions Manual

Configuration
4.8 Partner stations
4.8.2

Acknowledgment

Acknowledgment of frames
The receipt of a frame is monitored and acknowledged in different ways. The mechanisms
differ depending on the type of communication:
● Telecontrol communication
Frames received from TCSB are acknowledged immediately by the CP.
Frames sent by the CP are acknowledged by TCSB.
● Inter-station communication
Received frames are acknowledged immediately by the CP. The acknowledgment frame
is forwarded by the telecontrol server to the destination CP.
For sent frames, this applies in the opposite direction.
● Direct communication (Open User Communication)
The successful sending and receipt of frames is indicated by status displays of the
program blocks.
With TCP segments, the protocol-specific acknowledgement mechanisms are used.
4.8.3

Connection establishment

Connection establishment
● Connection to the telecontrol server
The connection to the telecontrol server is always established by the CP.
If a connection established by the CP is interrupted, the CP automatically attempts to re-
establish the connection. Note the settings for re-establishing the connection in STEP 7,
refer to the section Ethernet interface (X1) (Page 53).
Note
Connection interrupted by the mobile wireless network provider
When using mobile wireless services, remember that existing connections can be
interrupted by mobile wireless network providers for maintenance purposes.
● Connections with direct communication (Open User Communication) and S7
communication
Connections are established as soon as the corresponding program blocks are called on
the CPU.
This also applies to the situation when a different S7 station sends data. In this case, the
corresponding receive blocks are called by the receiving station.
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Operating Instructions, 04/2017, C79000-G8976-C381-03
CP 1243-7 LTE