No GPIB instrument visible in VISA control

[Joe_McC]

I'm using a GPIB-USB-HS interface with Labview 2012. I have a Keithley 2400 connected. I can communicate with this using MAX (ver 5.3.1f0) with no problems after scanning for instruments.

I downloaded the instrument driver from the NI site for te 2400, but when I open the llb, I don't see the instrument in any of the VISA resource drop down boxes. I see all my serial ports & printer ports, but thats it. Any pointers? I did see someone suggest that all NI software should be uninstalled and then reinstalled, but this seems really drastic! The VISA version is 5.2.

I have no problems with VISA & serial ports or USB ports.

Thanks for any help,

joe

[Dennis_Knutson]

Please clarify. There is no llb for the 2400 driver. It is a LabVIEW project style driver  and there is a lvlib. If you have an llb, it is an old driver.

[Joe_McC]

Sorry, you are quite correct, I was also working with an llb for a TG4001 today with which I'm also having issues.

The file I downloaded fron NI was IEEE 488.2 (GPIB)/Serial plug & play project version (http://sine.ni.com/apps/utf8/niid_web_display.model_page?p_model_id=1585)

I loaded the Initialise vi & there was code to distinguish the interface type (serial or GPIB), so I assumed I was OK. I could try the other version from Keithley, but I don't get why the other one will not work.

I'm upgrading the NI-488.2 on my system to 3.1.0 from 3.0.2, but not optimistic that will help.

Joe

[Dennis_Knutson]

If you don't have anything listed in the VISA dropdown, then upgrading the NI-GPIB driver will not help. What version of NI-VISA are you using? If you right click on the instrument in MAX, are you able to select and run 'Open VISA Test Panel'? Can you attach an image of MAX with the instrument selected? This should show the VISA settings for the 2400.

[Joe_McC]

When I open a VISA test panel, I get the following error

Error opening resource:
GPIB0::21::INSTR

LabVIEW:  (Hex 0xBFFF009E) VISA or a code library required by VISA could not be located or loaded.  This is usually due to a required driver not being installed on the system.
=========================
VISA:  (Hex 0xBFFF009E) A code library required by VISA could not be located or loaded.

I can communicate with the instrument. I attach screenshots. I had already started the IEE upgrade, but as you said it did not help.

Thanks,

Joe

[Dennis_Knutson]

You don't have NI-VISA installed if you are getting that error. Using the NI-488.2 Communicator only uses the lower level GPIB driver.

[Joe_McC]

Dennis,

Finally got it working. VISA was installed, but I've not used the GPIB stuff on this machine. I used the VISA test panel in MAX a couple of weeks ago for serial comms if I remember correctly.

The GPIB troubleshooting utility told me I had a problem with both the NI-488.2 software & my GPIB adapter. Device manager did not indicate a problem with the adapter & because I could communicate with the instruments in MAX, I thought it was all good. Obviously not because I uninstalled the NI-488 software completely & reinstalled it. Now all is good.

Thanks for the help,

Joe