Dumb instrument control

Hello,
We have developed a measurement instrument that passes raw data to the host PC via a USB interface. The instrument has little data processing capability.
The host PC runs the user interface (VB6) software to carry out all the data handling and processing.
We have developed a VB6 DLL library that can be called by another program to carry out the low level communication with the instrument as well as the necessary data processing.
The USB interface on the instrument is not USBTMC.
Now, we have been asked to provide a VISA driver for our instrument. We are unsure how this could be done. Would this simply entail modifying our DLL to accept VISA commands? If so, in genral, how could the DLL be 'knitted' into the users' application software?
Thanks!

Hi,
I am guessing you want your end users to be able to use your device with LabVIEW. If you are looking to do this, the best way forward would be to distribute your DLL to your end users. They can then integrate it with the LabVIEW code using a 'call library function node' in LabVIEW or better still if you are a LabVIEW developer, you can write a few basic VIs to encapsulate all the details away from your user.
If you want to make your devise VISA ready, I belive this would entail making the lower level communication protocols of your device compatible with the VISA API. Look for the VISA specifications here: http://ivifoundation.org/specifications/default.aspx.
Doing this would be like developing the USBTMC low level protocols.
However your USB device can be used as a raw device in NI VISA. Please read through this article for more information:
http://www.ni.com/white-paper/4478/en/
If your users do this, then they would not be able to use the VB6 DLL you have written and they need to know the specifics of the communication protocol of the device. This would mean a lot of work for the end user which is not recommended.
I hope this helps.
Thanks and Regards,
Supreeth.K
Applications Engineer
NIUK

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Dear Sir:
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Solved!
Go to Solution.

Thanks for you advice.
I think this problem is a lot easier than you might think.   I just started using Labview and the *.VI is super simple. I am away from my development computer right now so I can't post it.
The information I need to know right now are the typical files that are needed to be added in the build.
I found this quote that I found on a webpage to be interesting, (although I am not building an installer):
" Do I need to include NI-488.2 2.7.3 module if I use only basic GPIB Write.vi and GPIB Read.vis in my project?
Yes, if you are making an installer ..."
This is a link to the webpage:
http://forums.ni.com/t5/LabVIEW/Uninstalling-LabVIEW-after-an-application-EXE-build/td-p/1553310
My program involves only simple reads and writes using NI-488.2 calls to a test instrument.   A simple list of files specified with filename extensions to get me started would be appreciated.

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-AK2DM
~~~~~~~~~~~~~~~~~~~~~~~~~~
"It’s the questions that drive us.”
~~~~~~~~~~~~~~~~~~~~~~~~~~
Attachments:
SempahoreExample.jpg ‏256 KB

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Hey everyone!
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Do you also have a GPIB controller such as NI's USB-GPIB? Acable by itself its worthless. A better choice would probably have been the instrument with a USB or Ethernet connection, but no matter, the communication is the same.
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It is possible to control mulitple instruments on some buses (like GPIB). As for bringing up a GUI for each instrument, this is something that should be done in the programming language.
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What, exactly, causes the "REMOTE" indicator on your device to come
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Attachments:
controller.llb ‏513 KB
radiobuttonstatemachine.vi ‏14 KB

There are a few things to remember with LabVIEW. The reason your program only works in continous mode is that LabVIEW is a dataflow language, it executes the objects as their inputs are satisfied, then their results travel to the next "node". In your original program the messages to the instrument are in "nodes" that are all "serially" connected, so that unless you run it in continuous mode there is no loop back to the beginning to read any changes. When you start the program in the non-continuous mode it will read all the front panel settings almost instantly, "flow" to the message sending nodes and then end.
Can you get the full package? User interfaces are much easier to design with "events", but remember thoise were only added a few major releases ago, you just have to be trickier.
Here is a quick modification to your radio buttons.
Putnam
Certified LabVIEW Developer
Senior Test Engineer
Currently using LV 6.1-LabVIEW 2012, RT8.5
LabVIEW Champion
Attachments:
example 9-29-08.vi ‏15 KB

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I have recently decided to migrate from labVIEW to Visual Basic, as my applications are becoming more and more demanding. I have Visual Studio 6 for Visual Basic, and I have no problem coding and creating interfaces, but I have no idea where to start as far as communicating with my instruments over GPIB.
I have NI-DAQ for Windows version 6.9.2 installed and apparently it contains support for Visual Basic, although I can't figure out what that support is... are there librarys that I can include and call to? If so, how do I do this? Is it possible to communicate with my instruments without getting the NI Measurement Studio for VB?
Thanks everyone

Hi,
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Dumb instrument control

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