LabVIEW with Modbus RTU-Stepper motor

[OmidMN]

Hello All,

I'm new here, I wonder if you can help me out,

I have a stepper motor (bipolar-4wire) and a motor driver both from LAM technolgies. The driver interface is usb and comminucation protocol is Modbus-RTU. I'm using Laview2013 to get it working but no luck yet.

I've tried modbus libraries from here:

http://www.ni.com/example/29756/en/
https://decibel.ni.com/content/docs/DOC-30140

but neither work and most of tutorials I found use modbus I/O server.

Thanks

Omid

[BoKnows]

You've found a bit of a corner case for how we support things.  We officially support the DSC Module (which is where you'll find the I/O Server) and that means you'll find a lot of documentation on it.

For the libraries you listed, the forums are a good place to look for help.  But, you'll want to provide a bit more information to allow us to help you.  "no luck yet" doesn't really help us see where you're running into issues.

Have you successfully installed that library so you can see it in LabVIEW?  If so, there are a couple of example VIs that get created.  Have you run these to see if everything works if you're sticking with just the PC as both master and slave?  If not, I'd suggest doing this for a couple of reasons.  First, it helps you know you have it installed and all the dependencies working right.  Second, it gives you something in a working state so you can see how it's built and use that to make changes and start to bring your device into the application.  It's much easier to have something as a known good than everything being questionable.

[OmidMN]

Thank you Jeff,

The Modbus API has been installed sucesscully and I do see it in the adds-on.  However, the hardware is not recognized when it's connected via usb. I'm new to this and couldn't find a clean vi example file for stepper motors using this library. Is there any example/tutorial file to show the process from sctarch?

[BoKnows]

I'm not entirely surprised you didn't find an example specific to your application.  They're more often a bit more general.

Were you able to get the examples to work prior to trying to interface directly with your hardware?

If so, what happens if you use the Serial examples?  Do those talk to the hardware?  If not, you might take a look at what registers on your hardware are supposed to reply and try to talk to one of the status type registers just to see if you can successfully read from one.