Why do I get the error "Unable to create VISA object. The required drivers may not be installed properly." when using the Instrument Control Toolbox 2.8 (R2009a)?

I am trying to connect to a National Instruments GPIB device using VISA as follows:

gpibObj = visa('ni','gpib::20::INSTR');

When I do so, I get the following error message:

 ??? Error using ==> visa.visa at 241

 Unable to create VISA object.  The required drivers may not be installed properly.

 Type 'instrhelp visa' for more information.

I am using the following NI driver:

NI-488.2 2.7 - Real-Time OS, Windows 2000/Vista x64/Vista x86/XP

Answer 1

[MathWorks Support Team]

In order to be able to access your GPIB device using VISA you need to use a supported driver, which in this case would be:

National Instruments NI-VISA version 3.0 (or higher)

Reference:

 Instrument Control Toolbox - Supported Hardware - VISA

 <http://www.mathworks.com/products/instrument/supportedio13784.html>

For more information on VISA see:

 VISA Overview

 <http://www.mathworks.com/help/instrument/visa-overview.html>

If for some reason you cannot upgrade your VISA driver, then you can also access your GPIB device directly from MATLAB as it possesses this capability. For more information see:

 Controlling Instruments Using GPIB

 <http://www.mathworks.com/access/helpdesk/help/toolbox/instrument/f13-5310.html>