Labview and Modbus

[Bhadresh]

Hello

I want to communicate my modbus compatible devices with labview..

And therefore i need guidance about the library and software uses for that operation.

How can i communicate my devices with Labview.

Please tell me ....

[Bhadresh]

On website they are writing that: In the LabVIEW Project window, right-click My Computer and select New»I/O Server, but i have no that option..

Now what to do ?

[Dennis_Knutson]

On what website? A search on NI's site says to use either DSC (an add-on module you must purchase) or the Modbus library.

[Bhadresh]

i found from NI website :"http://www.ni.com/white-paper/13911/en/"

i have already intalled Visa4.5.

then what should do ?

[crossrulz]

That white paper is using the DSC toolkit, which is an add-on.  I suggest using the NI Modbus library that Dennis linked to earlier.

[Bhadresh]

i understand that but..

My poject is:

I have home made RS-485(2-wire) compatible modbus protocol supported relay card.

Its address is (41302) and slave ID is (11).

this whole word (41302) has its bitwise relay..

and i want to operate it from labview as individual switch for each relay.

This is my target..

So please help me for this..

If i'm sucssed in this project then i can use Labview in my another project..

[Dennis_Knutson]

So, what happens when you use the functions from the modbus library? What functions are you using? What settings? What errors do you get? 

Since this is a homegrown modbus device, I would strongly suggest trying some commercial modbus program to help isolate any problems to the hardware or software.

[Bhadresh]

I have already tested my relay card with Modscan software and it's alright.

I'm able to on/off relay from modscan.

And now I want to start working with Labview, I have done only internal program program but not work with external devices through COM port.

So I don't know how to start.

So please help me step wise..

How to start from beginning..

I know how modbus protocol works..