Does GPIB-USB-B controller not recognize device Aliases in Instrument I/O Asst express VI ?

[Mbdeck]

Hi everyone,

 I'm currently having problems with my device. I'm trying to communicate with the instrument simulator through the Instrument I/O express VI but the device alias I designated wasn't being recognized. After selecting the Alias from the pulldown menu and tried the "query and parse" command, there was no response. The "write" and the "read" commands also did not work. I'm suspecting that the problem is from my GPIB-USB controller card. I have the GPIB-USB-B controller. It recognizes only the instrument descriptor but not the alias. My NI 488.2 is of the 2.46 version and NI VISA is v4.2. I think everthing was configured correctly but the card might be the problem. Does anyone know how to fix this problem?. Is there some kind of driver upgrade that could help rectify it.

Thanks

[Dennis_Knutson]

Aliases have nothing to do with GPIB controllers and their software though if you cannot communicate to the instrument in MAX, then there might be problem with either one. Aliases are part of VISA. You can try upgrading to 4.5. Also search your entire pc for a file called visaconf.ini. Post back with the location and whether you found more than one instance. You can also try deleting the file and then go into MAX and do a refresh. You will have to recreate all aliases.

I am confused about something. Are you saying that if you use something like GPIB0::address::INSTR, communication works just fine but the exact same command with an alias does not work? If that's the case, there is nothing wrong with the GPIB controller. If that is not what you mean, then what does it mean when you say 'it only the instrument descriptor'? Another test of the gPIB controller is to use MAX to communicate with the instrument. Do not select VISA for communication. Just right click on it in MAX. This does not use VISA at all and if it works, then the controller and software are just fine.

[Mbdeck]

Dennis Knight

 Yes when I use an instrument descriptor such as GPIB0::address::INSTR, the communication works fine but when I replace it with an Alias it doesn't. This has been driving me crazy for a few days now. Do you know how I can fix this problem?.

Thanks

[Dennis_Knutson]

Did you do any of the things I suggested?

[Mbdeck]

Hi Dennis Knight,

I searched my pc and found only one file for the visaconf. location: c:\VXIPNP\WinNT\NIvisa.  I deleted it and closed Max as there was no refresh options on the toolbar. I also right clicked on the instrument in max and it worked as well. None of these steps solved the problem.

[Dennis_Knutson]

The Refresh is under the View menu. If you don't have it, then you either have a very old version of MAX or something is corrupted with the installation. If it's corrupted, you mihgt just want to uninstall everything a give it a fresh start.

The location of the the visaconf file also points to an old version.  It's been installed to C:\Documents and Settings\All Users\Application Data\National Instruments\NIvisa for the last couple of versions.

Message Edited by Dennis Knutson on 04-07-2009 08:06 AM