VXM control with Labview Visa ports not found?

[Charles Emrick]

Although at this point I do not believe it is a Velmex problem but a Labview problem I can not find an answer in the Labview Forums.

Using the VXM driver everything works GREAT, but I am looking at writing some functions that are not in the driver using Labview VISA so that I can use the same code in both 32bit and 64bit.

My 1st attempt is to configure the VISA but the "Visa Resource Name" does not show me any ports to communicate with????

I know everything works cause I can use COSMOS to communicate, and I can use the VXM driver to communicate, but not the Visa?
(I have also made sure that the port is not still open in COSMOS or the driver, so I can rule that out)

Again, not a Velmex problem but I hoped perhaps some users out there can point me in the right direction?

[VelmexControls]

Charlie,
I was looking at the same idea today and hit the same problem (dang it took all day to figure out why the only port found was "Refresh") and if you run the VI without selecting a port then you get an error that parameter 1 is missing (I think thats what it was telling me)

Very frustrating when you can not find a decent help file in a language you do not know *L*

Took me a long time of thinking, when I wondered something I figured out some 13yrs ago when a labview example I did would not work on a users machine? and determined that they did not have the "Run-Time-Engine" installed?
(Although I do not know why Labview did not install it when it was dependent on it)

Anyways try the attached to see if you get an error indicating that you do not have NI-Visa installed
(I still have no clue why I will not get an error unless I check for a return results but anyways)

Give it a shot

[colin...@gmail.com]

Hi Charles,

You should not have to configure VISA to make your code compatible in any way. This is very simple serial communication.

As for Run-Time, the only reason you need to install it separately is when you are running an executable built using LabVIEW on a computer that does not have LabVIEW installed.

Colin

[colin...@gmail.com]

Also, can you give me an idea of what you are trying to do with your newly created commands? I'm curious, and I might have some suggestions. I am a LabVIEW developer.

C

[Colin Reese]

Ok Charles, I saw your other post. Can you explain again why you would not use the nice dll wrapper that's been written? The commands are so simple that it seems to me that you'd be reinventing the wheel, and end up with more or less the same thing.

C

[Charles Emrick]

It appears that Cliff was right and I did not have VISA installed (Not sure why though cause it did appear as a tool in Labview)

So I went and downloaded the missing Visa files at http://joule.ni.com/nidu/cds/view/p/id/2914/lang/en

Now my beginnings look good cause I can see my ComPorts (as well as printer ports)

Colin,
This is just a learning experience for me since most tutorials I find in Labview are kind of worthless to me cause they do not really cover communications (Serial, USB, GPIB, etc)

I also like finding out why something does not work for me but seems to work for everyone else, then what am I not doing right? or what documentation did I miss? or is there any documentation that should cover the subject? or if the missing information is something that everyone just assumes you already know, when you don't???

Reinventing the wheel??....Yep, but now I know what it takes to make a wheel and not just buy one and use it.

[Colin Reese]

Hi Charles,

I certainly understand reconstructing something to understand how it works. I do it all the time. The sort of low-level communications that you're talking about, however, are not something that I find very interesting. I suppose it's a consequence of being /forced/ to write such code when it doesn't exist for hardware devices I want to use. So when I get a device that has some nicely written function calls via serial com, unless there are obvious features missing, I gladly use them. Anyhow, I was honestly just curious what you were after by rewriting them.

My philosophy - and what I base my business model upon - is that people have rewritten little bits of code that make things work far too many times. Over the course of many years of designing and building characterization tools, I have countless times written basic communications, low and mid-level driver code that I know has been written by somebody else at some time (and probably better than I wrote it at the time). Furthermore, solving these sort of little problems takes time away from solving the fun problems. For people that don't code, that's doing what the tool was designed to do. For people that do code, that's working on the more interesting coding problems, like designing a user interface or a neat acquisition or automation sequence. For these reasons, not only would have gladly used a free piece of low-level com code, I would have paid for it. My boss never patted me on the back for writing glue code!

Colin