System freeze

[D Sen]

I am running a labview routine (on a windows XP machine) which writes a command to one instrument (running the older GPIB IEE 488) and reads from another (with GPIB 488.2). This routine loops every second and writes data to a file every 3mins.

Now the systems (the entire computer) hangs, every now and again, usually when left running overnight. I'm wondering if this might be due to something wrong with GPIB communication or possibly something wrong with the computer itself. Clearly I could try running the routine on a different computer. I would appreciate any other suggestions to help debug the problem.

Thank you much.

[Shawn B.]

Since you mentioned that this usually happens when left running overnight, I'm thinking this might be caused by virus software. I would set your virus software to not scan the file you are writing to, and see if this fixes the problem.

Also did the program ever work consistently? If yes what has changed on the system?

Shawn B.
National Instruments

[D Sen]

Thank you for the response.

The virus scan is set to only scan when instructed. It doesn't scan automatically.

The main change is running the routine faster: every 1s compare to every 20s before.

That's why I was wondering if the crash could be due to GPIB communication error. I don't see any errors reported however, from GPIB write and GPIB read sub vi's. I've been told to try setting the communication option in the GPIB read and write to "communicate synchronosly" as opposed to "asynchronosly". I'll give that a try.

Any other suggestions?

Thank you much!

D Sen

ps. I am writing to a Krhon-hite 521 current standard and reading from a HP3478A digital multimeter.

[Shawn B.]

A GPIB read or write error shouldn't cause your system to freeze, but I guess it might be possible. You can try installing the latest version of NI-488.2 which can be found here. If your computer didn't freeze you could run NI Spy to capture the GPIB communication and any errors.

If you change it back to acquiring every 20s does it fix the problem? Did you also change how often it writes to file? I'm still thinking there is some other software that runs overnight on your computer and interacts with the file you are writing to. Make sure you do not have any software that does this.