Siemens Industry Online Support
Siemens AG
Entry type: Application example Entry ID: 20983154, Entry date: 03/29/2005

Routing of Data Records Between Different Subnetworks by Using a Gateway CPU

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One problem arising quite often in the field of industrial production engineering is the data exchange between stations integrated in different, heterogenous subnetworks. In contrast to PG routing, the routing of data records is not yet an integrated standard feature in the operating system of SIMATIC CPUs.

This task can be fulfilled by integrating a gateway station with a CPU equipped with suitable network CPs, so as to enable communication with both subnetworks. The use of the S7-protocol as a subordinate network protocol provides an excellent solution, since it can be used with both Profibus and Industrial Ethernet and independently from the physical structure, so as to offer an interface for the user which is identical on both subnetworks.

 The basic principle of this application can be illustrated as follows.

Based on this principle, a user program has been realized that offers individual parameter setting and an application suitable for the connection of up to 8 S7-400 stations via the gateway (S7-300), so as to enable bidirectional data exchange including acknowledgement of transmission.

The following graphic shows the hardware implementation in this example.


Content of Downloads


Documentation (German)
Routing of Data Records Between Different Subnetworks by Using a Gateway CPU
20983154_S7_Data_Gateway_DOKU_v10_d.pdf ( 3629 KB )
Documentation (English)
Routing of Data Records Between Different Subnetworks by Using a Gateway CPU
20983154_S7_Data_Gateway_DOKU_v10_e.pdf ( 1905 KB )
Code  20983154_S7_Data_Gateway_CODE_v10.zip ( 518 KB )




06/2004 first edition


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