NI-GPIB-USB HS ready or ative?

[poli]

I have a NI-GPIB-USB-HS adaptor , when switched on,  the "Ready"  LED  indicator is glowing, the "Active" LED indicator is not glowing.

My GPIB device shows up under devices and interfaces under Max but when i click on "scan for instruments", it says "instrument not found".

Is my GPIB adaptor ok?

My Labview VI is not working and i suspect  there may be problem with the adaptor, hence i describe its status above.

Regards

Neel

[pflores]

Your NI-GPIB-USB-HS controller seems to be working correctly. If you can see it in MAX, you are generally in good shape. When you run a Scan For Instruments, this queuries the GPIB bus to find out if any instruments are connected to the controller (GPIB-USB-HS). If there are no instruments listening on the bus, then you will get Instrument Not Found message.

What GPIB instruments are you trying to talk to? What is going on with your LabVIEW VI?

[poli]

Hi

Thanks for your response.

I am using keithley 238 meter which has a GPIB interface. The instrument driver at your website directs me to keithley website, and the VI i am using from keithley website is attached below.

The VI sweeps voltage from "start voltage" to "stop voltage" in increments of "step voltage" and displays the current measured as a table and a graph.

My keithley 238 instrument has an indicator "LSN" AND "RMT" meaning "remote  control"  pertaining to external software based control and "listen". I click on "Run" and these two indicators turn on.

But nothing else happens, in the VI i click on "set up linear stair sweep" and "run single sweep", but no use.

The instrument GPIB address is 16 and i assigned it my device properties available at MAX- Devices and interfaces and also at my VI.

What could be wrong?

The interesting part is this VI and the  gpib-usb  worked a few days back, but today it doesnt work at all.

please guide me systematically to find where lies the bug.

Regards

poli

[Dennis_Knutson]

What do you mean you assigned the instrument the device properties? There is nothing you need to do to an instrument that is found in MAX. Did you do something in MAX and after that the driver stopped working and MAX could no longer find anything?

[poli]

In MAX under devices and interfaces, it shows my device as GPIB0 and displays a series or properties, i changed the "primary address" field to 16 , which was originally zero, because my instrument keithley 238 showed IEEE address as 16 at start up.

 Should i reinstall the MAX settings etc by uninstalling driver and then reinstall?

At device manager, for this particular device,  it says "device working properly" and software as "pass".

Under MAX however, when i go to  device interfaces-> GPIB0, and right click on my device GPIB0 and click scan for instruments, it says "instrument not found"

But i am not sure what is wrong.

I need to go step by step to find out what is wrong.

[Dennis_Knutson · Accepted solution]

You do not change the address of the GPIB controller to match the address of your instrument. That is a very wrong thing to do. Each instrument on the bus has to have a unique address and each instrument has to have an address that is different than the controller. Change the address of the controller back to 0! You might want to find a basic tutorial on GPIB.

[poli]

Dear helpful NI staff

I am relieved to inform you that your suggestion has worked.

This was my first GPIB code, hence the elementary mistakes that i made.

Your technical support is of exemplary standard and that is why i always use  as many of your devices as possible.

Thanks once again and regards

poli

[Dennis_Knutson]

I do not work for NI.  The NI employees have a blue bar next to their name.

[pflores]

Indeed, Dennis is not an NI employee but he does help us out a lot!

Thanks Dennis!