No answer on query with TCPI/IP-GPIB (timeout)

[holmfred]

I am getting a timeout when i try the read the answer from a query to my spectrum analyser.

I am using a TCP/IP-GPIB-converter and a NI Visa. A software was shiped together with the converter to send separate commands to the GPIB-device. From this software I can set parameters and ask the spectrum analyser for its identification. This is not an problem. However, when I am using MAX and the Visa Test Panel, I can send commando to set parameters in the spectrum analyser but an cannot read the answer if a ask the spectrum analyser for its identification, I get a timeout. I can send a query from the Visa Test Panel and read it from the software that came with the converter.

My intention is to control the spectrum analyser from MATLAB and I have no problems setting the parameters but I cannot read any data from the GPIB-device.

Any ideas?

Regards

Fredrik

[Dennis_Knutson]

I'm a bit confused. The software that ships with controllers from NI is MAX. Are you using one from a different vendor?

[holmfred]

The TCP/IP-GPIB-converter is not from NI but they does not provied any VISA which I need to control the GPIB-device (spectrum analyser) from MATLAB. Instead they suggest to use VISA from NI. Since I cannot read from the GPIB-device from MATLAB I tried to use MAX. From here I can send commands but I cannot read and the same holds for MATLAB.

The supplier of the converter delivered a software (yes, a different vendor) which I can use to both write to and read from the spectrum analyser which means that the harware is OK. I suppose there is something with the VISA that I am doing wrong or maybe the hardware is not complient with the protocol that the VISA uses?

[Dennis_Knutson]

The vendor "suggested" you try NI-VISA? I would be very skeptical that this would work. Sorry, I have no idea what you could try. Perhaps the vendor might suggest a different method to use it with MATLAB.

You do know that NI sells an Ethernet-GPIB controller, don't you?

[holmfred]

Yes, the vendor suggested to use either Agilent or NI VISA. I choosed VISA from NI since I have used it before to control other instruments with success. These instruments communicated directly with the computer via Ethernet and I did not need the controller in between.

I think that I use the VISA in the wrong way or that my hardware cannot handle the communication with each other through the VISA since the software from the vendor does not have this problem.

Perhaps I should convince the guy how bought this controller to invest i device which does not rely on a third party software.

Many thanks for your time.

Fredrik