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Entry type: FAQ Entry ID: 38717202, Entry date: 06/22/2018

Why is communication between the Runtime simulation and the S7-1200/S7-1500 not possible if the PG/PC interface is not set correctly?

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The setting in the PG/PC interface must match the proper TCP/IP interface.

If the setting in the PG/PC interface does not match the proper TCP/IP interface, communication between the Runtime simulation (simulation of the HMI panel) and the S7-1200/S7-1500 is not possible. All functions like "Download to CPU" and "Determine status online" work, but the Runtime simulation cannot set up a connection to the controller. Please also refer here to the relevant information in the STEP 7 Basic Online Help under "Simulating projects".

We recommend the following procedure as a remedy: 

  1. In the Control Panel, you open the "Set PG/PC Interface" dialog.
  2. Under "Access Point of the Application", select "S7ONLINE (STEP 7)" from the drop-down list.
  3. Under "Interface Parameter Assignment Used", mark the interface "Broadcom NetXtreme Gigabit Ethernet TCPIP.Auto" that is connected directly with the device.

    Fig. 1
  4. Then click on OK and also confirm the next message with OK.

The Entry ID: 11870489 provides more information on parameterizing the PG/PC interface and on the following topics:

  • Adding and installing more interfaces.
  • With or without automatic recognition of bus parameters.
  • Device driver cannot be selected or is not visible.

The "TCP/IP(Auto)" setting in the PG/PC interface cannot be set in administrated networks if address assignment is via DHCP (Dynamic Host Configuration Protocol). The procedure for assigning the IP address from a DHCP server is given in the STEP 7 (TIA Portal) Online Help under "Call the address via "Accessible Nodes".

Creation Environment
The screens in this FAQ response were created with MS Windows 7.


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