how do i communication with modbus rtu ?

[coolraj]

Hi!
I have modbus rtu slave ( mitsubishi e50 e-terminal)which communicates with a master pc.Now I want to replace the e-50 with a another computer which will perform several other funstions using Labview.I can't change the coding for the master pc but I know the hex command it needs.can I simulate the modbus rtu slave ie e-50 in the labview pc ? If this possible please let me know how I can go about doing this.I'm pretty new to this concept !!
Thanks in advance
Raj

[Khalid]

Hi,

The easiest way is to use the ModbusSlave Object from the Industrial Automation OPC Servers (formerly called the Lookout Protocol Drivers). This software product offering from NI is basically a bunch of OPC Servers (called Objects)for the popular PLCs and RTUs. One of these Objects is the ModbusSlave Object. It does exactly what you are looking for -- it will act as a real RTU ModbusSlave thus turning your PC into a virtual ModbusSlave.

How does this work with LabVIEW? The ModbusSlave Object being an OPC Server, you can connect to it using the OPC protocol in DataSocket, or better still, using the Datalogging
and Supervisory Control add-on module for LabVIEW which has a built-in OPC Client and better support for higher IO points.

Hope this helps.

Khalid

[Olivier-JOURDAN]

Hi,
you can develop your own slave using the slave fonctions provided by the ModBus Driver provided at this URL :
http://www.saphir.fr/SAPHIRnet/Admin/home.htm

I hope this can help you...

[Olivier-JOURDAN]

URL has changed :
http://www.saphir.fr/FR/produits/pilotes/modbus/index.htm
... only in french for the moment.