Read/Write Allen Bradley Tag Values using Labview (Linux and Windows.)

[dirtyb15]

Just finished up writing some wrapper vi's that call on the libplctag sdk.  Did some very basic testing in Labview for Linux, and Windows. 

Hope it can help some others.

https://github.com/dirtyb15/libplctag-labview

[oschian86]

Delighted to test your project from Linux and Windows, I currently have LabVIEW_2016 for both operating systems, I would particularly like to ask if you can share the project in LabVIEW_2016 version.
I could assist with tests on AllenBradley Micro820 / 850 PLCs, and AB PowerFlex525 frequency inverters, since I have that hardware.
My cordial greetings,

[dirtyb15]

Sure I won't be able to convert it till Monday when I have access to my development system

[dirtyb15]

Okay, i added a zip file with the vi's saved for 2016.

[Brooks.Nelson]

Thank you for uploading the LabVIEW files.  I am new to labview so just trying to get this all installed correctly.  Can you tell me how I need to set this up for labview to work sending data back and forth.  Do I need to have the whole file in the labview PC?

Also, when converting a string from LabVIEW to a REAL number in PLC what is the best way to do so?  

Thanks.

I apologize for the NOOB questions.

[dirtyb15]

Not sure what you mean by the whole file? 

There is a simple example that shoes how to read and write a tag, i would start there.

To convert a string to real, there are existing labview functions to do that, look in the string/number conversion pallet.

[Brooks.Nelson]

I tried the simple read and write.  I was able to read but not write. So, I tried it the way I was originally doing it and I get the same 0.0, after I try to write.

[dirtyb15]

Were there any errors when you ran the simple read write? If so, what were they?

[jll41994]

I was wondering if you could also add for LV17?  I am new to PLCs but I am having to read and write tags from/to an AB 5069.  Can you explain each of the "PLC attributes" cluster elements used in Create_Tag.vi? Particularly the path, element size and element count.

[dirtyb15]

You should be able to save the 2016 vi's for 2017?

For Path, Element Size, and element count you really should read through info at https://github.com/kyle-github/libplctag , the creator of the sdk.

Path is basically where on the backplane physically the controller is. Element size, is just the size of the tag in bytes, and element count is how many elements in the tag if it is an array.  Make sense?

Working from home, i finally have some time to start actually using these vi's in my own project, and i should have some updates soon.