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Entry type: Application example Entry ID: 109474684, Entry date: 03/11/2015

Communication via the CM PtPs of the ET200 SP and the S7-1500 using the Freeport Protocol

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  • Associated product(s)
This application shows you how to use the serial interface for SIMATIC S7-1500 and the ET 200SP via Freeport protocol. As an example, the data of a Data Matrix handheld scanner MV340 is received via the serial interface and stored in the controller.

The examples show you

  • the configuration of the serial interface of the CM (Communication Module) PtP RS232 HF for the Freeport protocol.
  • the configuration of the serial interface of the ET 200SP CM PtP for the Freeport protocol.
  • the program-related handling for the data receipt from the handheld device SIMATIC MV340.

The figure below shows the structure of the two hardware variants.

Variant with S7-1500

Fig. 01


Variant with ET 200SP

Fig. 02

The largely identical solutions for S7-1500 CM PtP RS232 HF and ET 200SP CM PtP are described in two separate documents for reasons of clarity.

The programs offer you the following advantages:

  • Conveying general information about the Freeport protocol.
  • Demonstrating the use of the serial interface of an ET 200SP as distributed I/O of a SIMATIC S7-300 station.
  • Adjustable sample project for fast creation of own projects


Documentation und Sample Code CM PtP RS232 S7-1500

 S7-1500_CM_PtP_MV340_DOKU_V1_en.pdf (783,0 KB)

STEP 7 Project
 Registrierung notwendig S7-1500_CM_PtP_MV340_CODE_V1.zip (1,2 MB)


Documentation und Sample Code CM PtP ET 200SP

 ET200SP_CM_PtP_MV340_DOKU_V1_en.pdf (920,8 KB)

STEP 7 Project
 Registrierung notwendig ET200SP_CM_PtP_MV340_CODE_V1.zip (1,3 MB)


Further informations 

  • Master Slave Communication via a CM PtP using the Modbus RTU Protocol (Entry-ID)
  • Master-Slave Communication with Modbus RTU Protocol for S7-300 and ET 200S Systems




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