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Entry type: FAQ, Entry ID: 58497001, Entry date: 04/27/2015

What are the differences between the licensed version and the downloadable demo version of the blocks for Modbus/TCP?

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This entry gives you information about where you can download the demo version of the S7 OpenModbusTCP software and what the differences are to the licensed version.

The following entries provide a demo version of the S7 OpenModbusTCP software for connecting a SIMATIC controller to systems of different manufacturers.

The downloadable demo version has no function or time restrictions. Modbus communication can also run without a valid license.

If the Modbus blocks are not licensed, the INTF LED or SF LED of the CPU flashes. In addition, messages are entered cyclically in the diagnostics buffer of the CPU and the status value A090 (hex) is output on the Modbus block in the user program.

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