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Entry type: FAQ Entry ID: 17470979, Entry date: 02/28/2008

Where in STEP 7 Micro/WIN can you find the operations libraries for the Modbus RTU protocol and USS protocol?

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In STEP 7 Micro/WIN, the operations libraries for the Modbus RTU protocol and USS protocol are located in the "Libraries" folder of the operations tree.
The requirement for using the MODBUS function library is STEP 7 Micro/WIN version V3.2 and higher.

Fig. 01: ADD ON function libraries

These libraries are not components of the configuration software STEP 7 Micro/WIN, but are ADD ON function libraries.

In order to be able to work with the Modbus RTU protocol you must have purchased the software "SIMATIC STEP 7 Micro/WIN ADD ON: Function Library V1.1 (USS + MODBUS) for STEP 7 Micro/WIN 32".

The order number for this optional ADD ON function library is 6ES7830-2BC00-0YX0.

Order of installation:
First install the "STEP 7 Micro/WIN 32 Toolbox V1.0" (contains the libraries) and then "STEP 7 Micro/WIN".

This function library contains the libraries for the Modbus RTU protocol and USS protocol for STEP 7 Micro/WIN V3.2.

If you install STEP7 MicroWIN V4.0 SP8 and SP9 or higher for STEP 7 Micro/WIN V4.0, the operations libraries contain the following functions:

  • Modbus RTU Master V1.2 for Port 0 and Port 1
  • Modbus RTU Slave V1.0 for Port 0
  • USS protocol V2.3 for Port 0 and Port 1

More information
on the command libraries is available in the STEP 7 Micro/WIN Help or in the S7-200 system manual under Entry ID: 1109582.

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