The requirements to use Modbus protocol

[hofer]

In my project,I have to use the MODBUS protocol to communicate between the devices via RS232 using labview.So,I would like to know, how I can do this in labview and what are requirements i need.Any examples and references are welcome.

[tst]

Look here [broken link removed] for NI's example VIs for using Modbus.

[hofer]

Thank u for ur reply.I have seen the example VIs but I could not understand them ,as Iam new to this concept.Can u explain some important things which i should know.

[Donald]

"How I can do this in labview"

There are a lot of ways that it can be done. Besides the link that tst gave you, an excellent summary of the available LabVIEW/Modbus options was put together by Khalid awhile ago and can be found here.

"I am new to this concept. Can u explain some important things which i should know."

A lot depends on which option you go with and what your device(s) is/are. Searching this forum for previous Modbus discussions should help you learn things.

[hofer]

Thankyou very much for ur help.I have downloaded the example Modbus VIs from the link u have given.But I would like to know whether I should require all the VIs or only some VIs.Because when i opened the VI lot of sub VIs are opening so,Iam confused.please help me.

Have a look in to the attachment which i have downloaded from ur link

[vicky]

hey,
that VI is complete ,so all you have to do is connect a serial cabel BW your PC and the instrument,you have to select the PC port you will be using for the MODBUS ,and select the mode read input registers and start the communication.
WHat else do you want,for the theory behind Modbus you have all the links given.
cheers
vicky