VISA and Labview freeze intermittantly with GPIB-ENET100 remote GPIB server

[A Kane]

I have a problem with Labview freezing at seemingly random times when it uses VISA.

I am using LV 7.1 on Windows XP on two computers. Both computers are communicating with devices using a NI GPIB/ENET 100 remote GPIB server and a NI RS232-4 ENET 100 remote serial server.  In addition one of the computers is communicating with various hardware devices using a PCI-GPIB card.

Sometimes when I run, am running,  or even just open a Labview vi that uses VISA Labview will freeze on both computers,  In addition I cannot open the Devices and Interfaces tab on MAX. 

I believe that the problem is caused by the remote GPIB server because usually if I quit Labview and then turn the server off and back on Labview and MAX will no longer be frozen. 

I believe that my remote servers are correctly configured.  Does anyone know what the problem might be?

Thanks,

-Alex

[Robert M]

First off, what version of NI-488.2 do you have installed?  The latest version is 2.4, so if you have an earlier version, please upgrade.

How often does LabVIEW freeze and how long does it take?  Would it be possible to take a spy cature using NI-Spy?  It is a monitoring tool that shows what driver level calls are being made and any communication coming back from the device.  You should be able to find it at "Start >> Programs >> National Instruments >> NI-Spy".  Turn the capture on before communicating with your device.  Posting the capture will help in determining what's going on.

Hope this helps,

[A Kane]

Robert -

Thanks for helping.

I had NI 488.2 v2.3 installed, so I have now upgraded to v2.42 which you linked to.  Also I noticed my VISA version was 3.1 so I upgraded that to v. 3.2 .  I haven't seen any freezes since, but it's impossible to tell whether those upgrades fixed the problem yet. 

As far as the frequency of the freezes, it's tough to say.  Often when I first open them in the morning LV and MAX freeze, and once in a while they freeze during the day.  Once they freeze they are frozen until I restart the program.  Usually they freeze when I open a Labview program that references VISA, or when I look at its block diagram, or when I click on the Devices and Interfaces tab on MAX.  They have also frozen before while running a Labview program that is using VISA. 

(Continued)

[A Kane]

I turned on NI Spy before I opened MAX this morning.  When I opened MAX, MAX froze and NI Spy didn't capture anything.  Once I got it unfrozen by turning off the remote GPIB and then restarting the computer, here is what I captured on NI SPY when I opened Devices and Interfaces in MAX after I upgraded NI 488.2 and VISA:

I couldn't paste the capture log here, it was too long, but I have attached it. 

(I also have the captures pre-upgrade, if you would like to see them)

Let me know if this gives you any ideas.

Thanks again,

-Alex

(continued)

[Robert M]

Hi Alex,

The latest version of NI-VISA is 3.4, so you may want to upgrade to that instead of 3.2.  Also, what version of NI-Serial do you have?  I believe the latest version is 1.8. 

The spy capture shows MAX finding your DAQ card, 1 built-in serial port, your 4 ethernet serial ports, and 2 GPIB instruments.  Everything looks good there. 

NI-Spy didn't capture anything when MAX froze?  I would have expected it to show us which call made MAX freeze.  The very first call is to the resource manager, so it may be that the resource manager is causing the freeze.  When you upgrade VISA, MAX will get upgraded to 3.3.1, updating the resource manager as well.

Let me know if you are still freezing after upgrading VISA and NI-Serial. 

Hope this helps,

[ScottieB]

I wanted to interject one thing about this issue.  I remember a similar issue a long time ago where someone was using a GPIB-ENET/100 through a VPN connection.  You may not be running VPN, but do you have any "odd" IP network setup?  If it's a simple network with everyone on the same subnet, that I would say it's a normal network and this isn't the problem.

Scott B.
GPIB Software
National Instruments

[A Kane]

Hi Robert,

Thanks, I updated to VISA 3.4.1.  Also, NI Serial was not even installed on this computer, so I installed 1.8.0.  By the way I am only changing one of the computers so that the other can act as a control.

I will let you know if these updates have not solved the problem.

-Alex

[A Kane]

Scottie-

We're not using a VPN, but we are using what may qualify as an "odd" setup:  We are using static IP addresses on the Physics Dept. network at my University.  One computer is plugged directly into "the wall", while the other computer, the remote GPIB, and the Serial Server are all connected to the network through a switch, or "hub".  I probably should have mentioned this earlier.  Do you think this could be the root of the problem?

Thanks,

-Alex

[A Kane]

Hi Robert,

It appears as though there is still a problem.  I came in to check on it today, and when I clicked on Devices and Interfaces in MAX it hung for about 6 minutes before it opened.  This time I got a good NISpy log, and I have attached it.  The log indicated two errors on lines 52 and 53 on the attached log.

The other computer (called Trinity) interfacing with the remote GPIB also hung, but NI Spy did not capture any errors.  I have also attached its capture log  labeled Trinity).

One thing I noticed here is that the remote GPIB is listed as interface 1 on Trinity but as interface 0 on the other computer.  Is there any reason that could cause MAX to hang like this? 

Thanks,

Alex

[ScottieB]

Your network connections don't seem that abnormal, so my VPN theory is out.  It looks like, judging by your spy caps, GPIB0 isn't powered on or doesn't exist.  If I'm reading this right, lines 52 and 53 take 3 minutes each to complete.  This is pretty long; I'm not sure why your computer isn't timing out before 3 minutes, it should be about a minute.  In any case, why don't you remove GPIB0 from the system if you're not using it (you say you're using GPIB1, correct?).  You can remove it by deleting it from Devices and Interfaces in MAX (Measurement and Automation Explorer).  You could even change GPIB1 to GPIB0 if you wanted to make both your computers the same.  Do this in MAX by going to the properties page for the GPIB device and selecting the device-name dropdown box.

Scott B.
GPIB Software
National Instruments