NI GPIB USB controller not working properly

[Jahan]

Hello,

I recently purchased a NI-GPIB USB controller (HS) along with LabVIEW 8.6. I followed the instructions for installation of the driver, rebooted the computer and attached the device. However, the "ready" button of the device remains amber (instead of green. I can not communicate with my SRS830 Lock-in amplifier (using the code that I have successfully used previously). I called NI customer support. The person there was very nice, but was not able to solve the problem after spending more than half hour on the phone.

We tried restarting the computer, trying a different usb port, restarting the lock-in amplifier, and a variety of other combinations. But we could not get the ready button to go green.

I did not have good experiences with NI-GPIB USB controllers from my prvious lab and was somewhat hesitant about buying it. I knew that it crashed every so often and would also not let windows go to sleep. From 4 units that we had in the lab, at least 2 were sent back to for exchange at that time. However, I thought that they must have overcome these problems by now. But clearly, it still remains a problem.

Can someone help me with this problem? I would really appreciate it. I am using windows Vista, by the way. Does that make a difference?

[CharlesD]

Jahan,

Is the device recognized in MAX?  Did Windows recognize it as new hardware?  As you can see from the following document: Have you been to write simple comands to your amplifier? or any other GPIB instrument?  Possibly sending a "*IDN?" Query to aninstrument that supporets it to ensure that we can communicate to an instrument.  This would isolate your program from the hardware.   http://digital.ni.com/public.nsf/allkb/77CFE896188B63EC86256C0E00638769?OpenDocument

"A green READY LED means that the GPIB-USB-HS is operating at full-speed, while an orange READY LED means that it is operating at high speed." Where:

USB has 3 Different speeds

• Low Speed: Transfer rate for this speed is 1.5Mb/s
• Full Speed: Transfer rate for this speed is 12Mb/s. This transfer rate is now called 'USB'.
• High Speed: Transfer rate for this speed is 480Mb/s

Therefore an orange or amber light could be a good thing!

What exactly happens when you send the command to your Amplifyer?  

With regards to vista just ensure that you are using the 488.2 Driver for Vista which is found here: 

http://joule.ni.com/nidu/cds/view/p/id/335/lang/en

Let us know how things go

[Jahan]

Hi Charles,

Thank you very much for explaining the meaning of the color of the ready LED on the device. I figured out that part of my problem may have been my long GPIB cable (~8m). I switched to a different GPIB cable and now I can communicate with the lock-in amplifier normally. (With the long cable, it seemed that some of the commands would get executed while some others, including querry commands would not).

For now, I have communication with the instrument. However, I still have the problem that everytime I put the computer to power-save mode and then bring it back from the power-save mode, I lose communication with the instrument. However, if I restart the computer, everything is fine again. Do I have to do this? Or is there a way to get around it?

Thanks again for your answer about the LED color. Can you comment on the correlation between the length of the GPIB cable and the problem that I was facing?

Jahan

[CharlesD]

Jahan,

I'm happy t hear that you were able to start communicating with your GPIB instrument! Please see the following  Knowledgebase article that describes the different GPIB Cable lengths and how they affect performance: 

http://digital.ni.com/public.nsf/allkb/CD66538B9541F474862570820047B175?OpenDocument

With regards to the power save mode problem,  I've also seen it happen with other USB devices (Not GPIB devices).  Have you tried unpulgging and replugging the USB-GPIB-HS device.  Does the system recognize it then? Have you tried disabling and then enabling the USB Port from device manager?   I would try these two things next time this occurs and see if this resolves the problem.

By the way does this happen in standby mode or hybernate mode? 

[CharlesD]

Jahan,

The other thing I think could be causing your USB-Device to stop working after hybernation is that if you have a GPIB application running before entering hybernation, when the computer boots back up the handle that the application was using is no longer valid.  If this is the case and this can be verified by using NI-SPY to monitor the commands being sent to the instrument (http://digital.ni.com/public.nsf/allkb/282C5D41E2BA04F2862574BA007803B9.  The important part would be to get the spy capture upon coming out of hybernation.  

More than likely you can simple close the handle  (using ibonl ( handle, 0 ) ), and then open a new one using ibfind or ibdev commands.

[Albert.Geven]

one other thing you really need to check is the bus speed.

The default is the highest possible speed but 2 microseconds handshake is much better for the bus especially when using longer cables.

And the sr830 is not fast at all anyway.

You can change this in MAX when slecting the interface properties