Siemens S7-300 - Page 95

Configuring communications connections
5.2 Connections to partners in other projects
Configuring and commissioning S7 CPs for Industrial Ethernet
Configuration Manual, 09/2013, C79000-G8976-C182-13
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● Declare readiness for communication - passive connection establishment
The connection establishment is set to "passive" for this situation.
The address setting for the ISO-on-TCP connection is then as follows:
The remote IP address and the remote TSAP are empty because they are not relevant
for the CP. When the connection is established, any partner is accepted (partner =
connection name) that addresses the CP with the correct IP address and TSAP.
It is also possible to use a partial specification; in other words, communication is
permitted with any partner that matches the specified TSAP.
● Connection to a specific station in any project
The address setting for the ISO-on-TCP connection is then as follows:
You can specify the remote IP address and the port of any destination station. The
destination station can be in the current STEP 7 project or in another project.
Use this method if you have not created a substitute object for the partner station, for
example SIMATIC S5, in the current project.
● Connection without specified port
TCP connections are unspecified in the following situations:
– The local port is not specified (active connection establishment).
– The remote port is not specified (no active connection establishment).
● IP addressing using DHCP
If you select the option to obtain the IP address from a DHCP server, it is initially not
possible to create a fully specified connection in the STEP 7 project because the local IP
address is not known. You must therefore select "unspecified" without active connection
establishment as the connection type.
The following table lists the possible options.
Table 5- 1 Setting the "remote" address parameters
Meaning for connection
establishment
IP address /
MAC address
(remote)
TSAP / port
(remote)
Active connection
establishment
by any partner
empty
empty
no
by any partner via specific TSAP
empty
specified
no
to or by a specific partner specified specified Yes
The local port can remain
unspecified (but not
necessarily).
to or by a specific partner
specified
unspecified
no
The free UDP connection is another variant. With this type of connection, the address of the
connection partner is left open during configuration. The communication nodes are identified
by address information in the communication job in the user program.