GPIB Instrument control with VB6

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,
You should be able to program using Visual Basic without any issues. There are examples already created that should have installed on your system in C:\Program Files\National Instruments\NI-488.2\Languages\Visual Basic\. In that directory is the language interface files and some good examples.
Hope this helps out!
Aaron K.
Application Engineer
National Instruments

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Attachments:
graph.png ‏12 KB

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Pete.

Desperate user need help. My GPIB instrument get stuck with my labview program frequently

Hello to all labview users,
i am a beginner in using labview. I am currently writting a labview program to automatically control a digital control rotator HD201e and a network analyzer 8720a to work with the anechoic chamber. The program receives an initial position, amount of increment and # of steps. My program will then ask the controller to rotate to the initial position and at the meantime, the program will monitor the position of the rotator to ensure the requested position is reached. After that, at the position, the program will ask the NA to perform a reading of the measurement. Once the reading is done, the program will ask the controller to rotate to the next position and does a reading of the measurement and so on.
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Usually, that problem occurs after few positions have been reached.....
so, when that happens, i have to stop my program and re-run it. that means the program will have to re-do the measurement that were read previously....
sometimes i have to stop and re-run my program several times to get all the measurement of all the positions done.....so...that bug renders that program to be an unefficient program.
I have been trying to resolve that bug for weeks...but no success....i have tried to put some wait time between each block....result is not much different...
I have also tried putting "clear" block before and after the "write" block.....same problem.....
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i have also even tried using "lock asyn" and "unlock asyn" block...but didnt seem to work....
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PS: i attached the controller part of my program and the overall program
desperate happyguy......
Happy guy
~ currently final year undergraduate in Electrical Engr. Graduating soon! Yes!
~ currently looking for jobs : any position related to engineering, labview, programming, tech support would be great.
~ humber learner of LabVIEW lvl: beginner-intermediate
Attachments:
HD201_Controld.jpg ‏231 KB
AChamber_Measurements_v1d.jpg ‏857 KB
AChamber_Measurements_v1d3.jpg ‏463 KB

hi xseadog
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Happy guy
~ currently final year undergraduate in Electrical Engr. Graduating soon! Yes!
~ currently looking for jobs : any position related to engineering, labview, programming, tech support would be great.
~ humber learner of LabVIEW lvl: beginner-intermediate
Attachments:
HD-201 RPosd.jpg ‏39 KB

Using Visa "resource name" control with GPIB example

good morning
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means Ni-Enet is GPIB0 and HP-HPIB card is GPIB1.
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in the Labview<>GPIB example but it failed. ("visa resource name" shows all resources includes GPIB0 nad GPIB1)
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a bit long , but hope the issue is clear enough..
thanks in advance
Happy new year.
Simon

You can't use that example with an Agilent GPIB board. The GPIB functions are only for NI boards and the NI-GPIB driver. You should be able to convert it to VISA but you'll have to replace the GPIB Writwe/Read with VISA Write/Read as well as changing the GPIB Address String to a VISA Resource Name.

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Attachments:
callback vi.png ‏8 KB
register event callback.png ‏8 KB

You would wire the event registration wire that comes out of the Register for Events node into an event structure. You will need to right click on the event structure and check off "Show Dynamic Event Terminals" and it into that. Then you can create a new Event Case that uses the dynamic event. You can place your subVI in that event in whatever way you want. (Just drop the subVI in or do a Call by Reference there, or whatever.) Look in the Example Finder for "Dynamically Register for Events.vi".

Can I use GPIB instruments via GPIB-USB-HS and NI-VISA on MacOS with Matlab somehow?

I've just installed NI-488.2 (14.1) and I can see my GPIB instruments in the NI-MAX app. However I can not find them in the tmtool function in Matlab. Aparently Matlab on mac does not support GPIB (http://se.mathworks.com/help/releases/R2014b/instrument/supported-hardware.html) but it does support VISA.
Do you think there might be a way to connect to my devices in Matlab through VISA some how?

Hi thanks for you answer.
Yes, I installed this version: http://www.ni.com/download/ni-488.2-14.1/5090/en/ which says: "NI-488.2 for Mac OS X, Version 14.1, installs NI-VISA and NI-MAX by default". I can also see all the correct .framework-files in the "Library/Frameworks/"-folder:
And since I can see (and query) the GPIB devices in both the "/Applications/National Instruments/NI MAX.app" and "/Applications/National Instruments/NI-VISA/NI-VISA Configuration.app/
HOwever Matlab does not want to detect any VISA drivers...

How do I create Labview VISA ports for *individual* GPIB instruments using Prologix USB GPIB controller?

Hello,
I'm trying to use a Prologix USB GPIB controller to control GPIB
instruments, and I would like to have a virtual serial (VISA) port for
*each instrument*, as is the case with a normal GPIB controller with a
standard NI driver. However this is not what the Prologix driver
provides -- it provides a single VISA virtual serial port for the
entire controller. To address the instrument with GPIB address 11,
you first send "++addr 11" to the serial port, and then you're talking
to instrument 11. However, this means I have to change all old
Labview programs.
Is it possible to create a "wrapper" function of some kind that will
define a virtual serial (VISA) port for each *instrument* on the
controller? For example, to talk to GPIB instrument 11, call it
ASRL3::11::INSTR, each time it is written to it would have to write to
the virtual serial port of the controller, say ASRL3::INSTR, first "+
+addr 11" and then the command that is sent to it.
A clearer explanation of the difference (i.e. incompatibility), and of
my objective:
1) A normal GPIB controller with NI driver: I go to the NI
Measurement & Instrumentation Panel, under GPIB, and Scan for
Instruments; all the live instruments show up; subsequently when I
want to use Labview programs that use VISA ports, the VISA drop boxes
allow me to choose a different port for each instrument, e.g.
"GPIB0::11::INSTR", "GPIB0::12::INSTR" would be instruments at
addresses GPIB 11 and GPIB 12.
2) The Prologix GPIB controller that plugs into a USB port: In
Labview you get a *single* VISA virtual serial port, ASRL3::INSTR, for
the entire GPIB0 controller. Therefore to address GPIB instrument 11,
you write "++addr 11" to the virtual serial port ASRL3::INSTR, and
then you are communicating with device 11, so you can write and read
ASRL3::INSTR to talk to that device. Then to talk to device GPIB 12,
you write "++addr 12" to the same VISA port, and then you are talking
to that device. The problem is that this requires recoding all
Labview code, whereas I would like to be able to use the same program
either with a normal or with a Prologix GPIB controller. Therefore, I
would like to create code that scans the controller for all GPIB
attached devices and creates VISA ports for all. Such ports, when
written to, would have to first write "++addr DEVICENUM" to
ASRL3::INSTR (i.e. the port of the GPIB-USB controller) where
DEVICENUM is the GPIB address of the instrument corresponding to that
port, and then would have to do a write or read or whatever function
is being done on that instrument VISA port.
I haven't figured out if it is possible to do this easily. Help and
pointers on where to look for hints would be much appreciated. Many
thanks!
Milos

My first impression is that if you don't want to make any changes at all to existing programs is that the wrapper you need is one around VISA. You would need to intercept all of the calls into the NI VISA driver. If you create your own visa32.dll and in there, change the addressing and then call the real VISA driver, you might (repeat, might) get something to work. If this would even work, you still might find that you have to make significant changes anyway. The serial connection is going to be considerably slower, and interface specific functions such as service request handling, bus triggering of multiple instruments, etc., would be difficult to impossible. This would be a lot of work, imho, to just save a couple of hundred dollars over a real GPIB controller. I've seen this Prologix device before and have even used NI's RS-232->GPIB controller. The Prologix intended use to me seems to me more for a hobbyist or very casual user. Of course, I'm used to having multiple GPIB instruments worth 10s/100s of thousands of dollars and the cost of an fully compliant GPIB controller is just lost in the noise.

Instrument Control Build Specifications

Dear Sir:
      I am trying to build a working *.exe instrument control program. This is a simple program which only queries my test instrument with a *IDN? command.
      The program fails to call my instrument driver and the program also runs on boot up when (running under normal conditions) it should wait for me to input the GPIB address of my test instrument.
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       When I run the program as simple *.VI in the Labview environment, the program runs perfectly.    No issues.
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       The *.EXE program fails to initialize correctly and fails to establish connectivity with my test instrument.
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1) The program runs on "boot up" when you click on the *.EXE program.   In *.VI mode, the program does not run on boot but waits for the user to input the GPIB address of the test instrument - program run is designed to be enabled by the user.
      I do not believe this is the source of the problem but only an incidental consequence of the problem.   If I stop the program and input the GPIB address, I receive a message about not being able to communicate to the driver.
2) Once the *.EXE program runs, there is a condition whereby the operating system cannot close the program and WINDOWS itself cannot shut down itself unless I manually close all the programs associated with the *.EXE program in the WINDOWS operating environment.
3) If the labview program and *.EXE program are closed but the operating system is still running, Agilent Connection Expert and MAX can no longer communicate with the test instrument.   They no longer see the test instrument.
It is obvious that the *.EXE program is making a change which is causing the operating system to "hang" on shutdown and is also preventing the other programs from operating as they should.
I believe the source of my problem may be how I programmed my build specifications.     In reply, can you please tell me what are the minimum requirements for the build specification so that my test instrument can reply to a simple *IDN? query?   What files are normally required for a successful build?
Other information as to the source of my issues are welcome as well.
Thank you.
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.

How to run GPIB based programs with visual basic 3

I have a little test program to comunicate with a GPIB device in a similar way that MAX does.
I type the address of the device, send the command *IDN?
but nothing returns except an error message that says s$ duplicate definition. I'm not terribly familiar with VB 3.0 Does anyone know what this means and how to fix it?

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Please let me know if you need any additional information. Any help would be appreciated. Thanks in advance!

I have looked over your vi. First of all you have to do some changes in the "ARSPS Initialize.vi" See picture.
The best way to check instrument communication is to send the *IDN? Command. The instrument will indentify itself in response to this command. The vi I have included is a labview example. Use this Vi to test your communication. Do not progress before this is working. The VI is also an excellent example on how to set up and close down RS232 communication.
The VI "Tfeedbackpowercontroller-nolvdt-Dinh.vi" looks OK so I guess it will work then your RS232 communication with the SPS200-50-A022 is working
good luck
PS as mentioned before you will find all the RS232 details in the instrument manual
Besides which, my opinion is that Express VIs Carthage must be destroyed deleted
(Sorry no Labview "brag list" so far)
Attachments:
sample.PNG ‏38 KB
Basic Serial Write and Read.vi ‏29 KB

Trouble reading data from GPIB instrument using VISA

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Hameg power supply HM7044 ieee 488 (GPIB) device control

Dear All,
I have a power supply (Hameg HM7044) with a GPIB interface.It seems that there is no VI to control it in the HAMEG or the ni websites.
Since i am new to this kind of interface i have two questions.
-if i connect the device how do i know the address it is in.
-is there a general VI to interact with GPIB -ieee 488 devices?
thank you in advance,
thodoros

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GPIB instrument holding up bus

I am having an intermittent problem with my GPIB system. Occasionally and seemingly randomly, one of my instruments holds the GPIB hostage; no other instruments can use it. The controller is the Agilent GPIB card and is accessed using the NI Tulip Passport. The device is power cycled and the bus is released and normal communications proceed.
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Can anyone help me with this? I am going to try to replicate the problem, but I'd like to know if this is theoretically possible.
Thanks,
Nate
-Nate

Hi Nate,
I believe the following forum post will help you:
http://forums.ni.com/t5/Instrument-Control-GPIB-Serial/how-do-i-tell-labview-to-release-a-GPIB-resou...
To summarize, it seems like you can with VISA. However, using functions from the 488.2 drivers aren't as straight forward. However, GPIB devices don't really have a "session". You've got various states, such as talker, listener. It is up to the controller to keep and set these states for the device.
Hope this helps.
Regards,
Che T.
Applications Engineer
National Instruments

GPIB instrument driver identification

What is the right labview GPIB instrument driver for ESP300 motion controller produced by Newport Inc.?
The drivers for motion controllers of Newport posted in ni.com website looks all different with the models provided by newport.

Hamfery,
The drivers provided on our website don't apply to your Newport motion controler.Newport is providing motion utilities for this model. It's been written in LabVIEW but you cannot edit it since it is an executable.
Cyril Bouton
Applications Engineering
National Instruments
Cyril Bouton
Active LabVIEW Developper

GPIB Instrument control with VB6

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