Simulink model <-> Modbus RTU <-> Industrial Controller

Hi,

We want to connect an idustrial controller to a Simulink process model. The communication between the two modules should be Modbus RTU. We want the controller to send and receive data to/from the Simulink process model (holding registers) about every second or every other second.

Initially we wanted for simplicity to run Simulink on my personal computer and use my personal computer’s COM-port for the task (Using a USB to RS232 converter), but as I have searched the Matlab forums on the internet it seems like it is not possible to get the Modbus communication up and running with the external industrial controller this way, can you confirm if this is correct? Please also give us any tips and tricks and recommendations for this to work. Earlier I have used my personal computer with a running simulink model to talk with an industrial controller using the Matlab OPC toolbox, therefore I do not understand why it should be that hard to achieve the same using something like a "Matlab Modbus RTU toolbox", if that exists..

In case running Simulink on my personal computer with Modbus RTU communication to the industrial controller is not possible, would you recommend using the Real time target machine for the task? In that case, what do we need of additional hardware and software for this to work? We already have the following:

- A Mobile Real time target machine - Simulink Coder (formerly Real-Time Workshop) - Simulink Real Time (or formerly XPc Target)

Thank you in advance for the help.

Best Regards, Sten Even