LabVIEW

cancel
Showing results for 
Search instead for 
Did you mean: 

printcapture/labView Conflict

 I tried a utility <PrintCapture> (www.printCapture.com) to take screen dumps to my PC (from an old HP spectrum analyzer). Worked like a charm--until I opened my LabView GUI. The GUI does not use the GPIB port or card, but it apparently preempts the <printCapture> software and prevents its operation. The vi hierarchy with the GUI shows no reference to GPIB.
 
Can I force the operating system to give the <printCapture> utility priority?
 
Do you know of a switch within LabView to disconnect the GPIB (even if it's not being used, as in this case). I tried uninstalling the GBIP from within the LabView utility <Measurement & Automation Explorer> and this disables the card completely.
 
David Ehrenberg
732 513 4384 cell
0 Kudos
Message 1 of 7
(2,997 Views)
Hey David,

How do you know the GPIB card causes this problem?  What do you mean by "preempts the software and prevents its operation"?

Thanks,
Jason W
Application Engineer
National Instruments
Message 2 of 7
(2,965 Views)
Jason, read my email again. Starting LabView severed the link to printCapture. LabView generally does not trash other applications on my PC, but starting LabView caused printCapture to fail.
 
The GPIB card is from National Instruments, a PCI-GPIB, serial number: 00BFAD3C
 
Will National Instruments software always preempt other applications on National Instrument hardware? What are my options?
 
DE
P.S. this is my second reply, the first <submit> try came back page not found.
0 Kudos
Message 3 of 7
(2,941 Views)

Hi dehrenberg,

As Jason asked, how do you know it is the GPIB that causes the problem?  Is this 100% reproducible, as in, does the printcapture immediately fail when you open LabVIEW?  LabVIEW has not been tested with this utility, so that is why we need this information.  Does it cause any other hardware on your system to fail?  Is there any other software that you have tested to see if it does the same thing?  National Instruments software is designed to be fully compatible with National Instruments hardware, so what do you mean by the "software always preempts other applications..."?  We need to determine if this is an issue on the GPIB side or on the LabVIEW side so we can troubleshoot further with you. 

Have a great day!

Chris R.
Applications Engineer
National Instruments
Message 4 of 7
(2,912 Views)

Chris, sorry for the tardy reply, there was no email generated by your reply on the 10th.

your wrote: Is this 100% reproducible, as in, does the printcapture immediately fail when you open LabVIEW?

"Immediately fails" is difficult to determine. With enough trials, I might be able to corrupt a transfer-in-progress, but the symptoms are: screen capture works when LabView is not running, screen capture fails when LabView is running. The screen capture fails at the first LabView window (the splash screen asking for <New VI> or <Open VI>).

I was not trying to operate any other GPIB instruments during the printCapture session. The only instrument physically connected to the bus was the HP spectrum analyzer.

My test set is still manually operated and I don't have other GPIB applications running. (If I do use the GPIB, it will probably be through the LabView interface.)

The problem looks to me like a classic competition-for-resource where LabView will not release what it thinks is a dedicated resource. If the (National) GPIB card is not reference from within the GUI, is the GPIB card free to be accessed by other programs?

The trial version of printCapture is free. An instrument with a <print> command can be use to test the utility.

David Ehrenberg, dehrenberg@multiplexInc.com

 

0 Kudos
Message 5 of 7
(2,871 Views)
Chris, did you see my reply?
 
DE
 
0 Kudos
Message 6 of 7
(2,848 Views)
Chris, I am again using printCapture with the HP spectrum analyzer and the lockout no longer occurs. I don't know what's different this time. I think I've done a reboot of my PC in the past week, but I don't think anything else has changed.
 
I tried starting LabView in the middle of the screen dump and both programs operated without problem. I stopped printCapture and then restarted printCapture after I had labView running. printCapture operates without problem.
 
I stopped printCapture and LabView then restarted LabView followed by printCature. LabView and printCapture operate without problem.
 
Perhaps it's the phase of the moon, The current phase of the moon is: new moon.
 
DE
 
0 Kudos
Message 7 of 7
(2,845 Views)