modbus labview 2009

[Jaime Rodriguez]

Has anyone worked with the Modbus Library and Labview 2009??? Is the 8.2 library compatible with Labview 2009??? I just wanted to have some input before I try it...

Thanks

[LV_Pro]

I'm using the MODBUS library with LabVIEW 2009, and it seems to work ok. The biggest problem I have had was that the instrument that I am talking to has mistakes in its documentation, that cost me a lot of time until the instrument manufacturers people identified that problem.

[Jaime Rodriguez]

Are you using the 8.2 library???

[LV_Pro]

Which is the 8.2 library? When I do a search on ni.com for LabVIEW Modbus it returns a link to Modbus Library for LabVIEW  version 1.2.1, which requires 7.1 or greater. I'm pretty sure that is the version I'm currently using, although I'm not able to check it from here. I haven't checked to see if the problems listed at the bottom of that page have been addressed in this version of the library, so keep that in mind. As it will be an early version of LabVIEW it will require a recompile of the library, or you will get a message to save each vi you use because of the normal recompile when it is loaded by a newer version. Normally you don't want to be changing "stuff" in the vi.lib directory of LabVIEW, but in this case ... I didn't run into any obvious problems with using it in 2009, but as I said I'm not sure of whether the "8.2" library is the same one we are talking about, since the one I pointed you to requires 7.1 or higher, which would mean it is 7.1.

Happy New Year

Message Edited by LV_Pro on 12-31-2009 08:43 AM

[Jaime Rodriguez]

Thanks a million for your help!!! I will try it out...

[plessnick]

A know that this thread is a few months old but here is what I'm seeing.

I have Modbus 1.1 and update an application, running as a Modbus slave , from LabVIEW RT 8.5 to LabVIEW RT 2009 f2.  The application is logging a message when the number of active connection is 0 (disconnection).  I've started seeing disconnection entries in the log a few times (10 to 20 times) per day as soon as I turned on the 2009 application.  The application is using the MB Ethernet slave.vi with a simple modification to write the number of connections to a LabVIEw style 2 global.

Initially I has suspected the customer network but I'm now seeing the problem at multiple sites when updating the PXI.  I'm planning to  add a few log capabilities to the "MB Ethernet Wait on Query.vi" next week to dig into this issue. It may be a Modbus issue or something related with the TCP driver. 

Patrick