0403-11 LOGO 0BA8 Remote IO

Example Projects > 0403 Siemens PLC Communication > 0403-11 LOGO 0BA8 Remote IO

Using Siemens LOGO! as remote I/O for REXYGEN

This folder contains the source files for the demonstration project on using Siemens LOGO! 0BA8 as remote I/O unit, just like in the case of Modbus TCP I/O devices.

There is a dummy project for LOGO! which must run in the device. See the logo_dummy.lsc project. The LOGO! acts as a server.

There is also a project for REXYGEN, which illustrates the direct access to Inputs (I, AI), Outputs (Q) and backlight from REXYGEN algorithm. REXYGEN acts as a client and connects to the LOGO! base module via Ethernet.

Analog inputs of the LOGO! are read and stored in the TRND block in REXYGEN algorithm, which provides a time-plot of the measured data in real-time.


  • REXYGEN Runtime Core and S7Drv modules are installed on the target device
  • The LOGO! device is in RUN mode (logo_dummy.lsc attached)
  • The IP address is assumed in the LOGO! device. If the IP address differs, remember to change it in the configuration dialog of the IO driver file according to your LOGO! base module. As was already mentioned, LOGO! acts as a server the clients connect to.

Timing of the project

  • The algorithm runs each 100 milliseconds (0.1 s). See the EXEC function block,
    tick x ntick0 = 0.01 x 10 = 0.1 s
  • Communication with Siemens LOGO! is performed each 50 milliseconds (0.05 s). See the S7C function block, tick x factor = 0.01 x 5 = 0.05 s

Running the example

  • The *exec.mdl file is the project main file
  • Open it with REXYGEN Studio, compile and download it to the target device

User interface (HMI)

The example is accompanied by a graphical user interface generated from REXYGEN HMI Designer.


Additional information

  • Siemens and LOGO! are trademarks of Siemens AG.
  • The S7Drv driver of REXYGEN uses the Snap7 communication suite.
  • Visit the REXYGEN webpage for more information about the example projects and developing advanced automation and control solutions using REXYGEN.