Error 6 @ GPIB Write

[Asalerni]

Hello!

I'm currently working on a flash photolysis instrument using labview. Recently I have upgraded the computer and now have error 6 occuring randomly throughout the program. I've tracked the errors down to the GPIBwrite command which happens to be used throughout the program. After doing some reading and asking a few questions, I'm pretty sure its due to race conditions but have been unable to fix the problem (Probably due to me being a novice with Labview). Just wondering if any pros out there could lend some assistance, I've attached a jpeg of the problem area!

Thanks!

[ben64]

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@Asalerni wrote:

Hello!

I'm currently working on a flash photolysis instrument using labview. Recently I have upgraded the computer and now have error 6 occuring randomly throughout the program. I've tracked the errors down to the GPIBwrite command which happens to be used throughout the program. After doing some reading and asking a few questions, I'm pretty sure its due to race conditions but have been unable to fix the problem (Probably due to me being a novice with Labview). Just wondering if any pros out there could lend some assistance, I've attached a jpeg of the problem area!

Thanks!

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No race condition can be seen from the part of the code you are showing. You can try changing to I/O mode (switching between Asynchronous and Synchronous) by right clicking on the GPIB Write function .

Ben64

[Asalerni]

The error continues in both Asynchronous and Synchronous modes, any other reason I might be getting an error out during GPIB write?

[Dennis_Knutson]

Can you attach the actual error message? The program looks like it was converted from LabVIEW 5 code. What version of NI-488 are you using? What os were you using and which one now?

[Asalerni]

Thanks for the response,

Was using Labview 2009 on windows 98 to Labview2009(32bit) on windows 7 (64bit). NI-488 is on version 2.71. This program has been modified and updated by several people over the years, it is now currently my project and I would love to see this system running again but I'm being forced to learn labview as I go.

[Dennis_Knutson]

Definitely update NI-488 to a version supported on your os. Think about using NI-VISA instead of the lower level gpib functions.

[Asalerni]

Updated my NI-488 driver and I've narrowed down this error a little more, but it is beyond my understanding. If I probe the Write error in, and Write error out the program will run fine for an indefinate amount of time(Pic1) but as soon as I remove the probes I'll be lucky to get 30 repetitions without Error6 coming back into my life(pic2). Really don't know what to make of this...

[Dennis_Knutson]

You can get this error when a write is issued before a read is complete. Since you have upgraded the pc, your code is going to execute faster. The probes are probably slowing things down just enough for the read/writes to work done of the time. A quick hack to check this would be to add a delay after the GPIB Read. You could attach your entire program to see where the problem actually is.

[Asalerni]

I've cleaned up the program and put it into a zip folder. I've put in some delays before and after the read and write vi's, however now the program is getting error 6 at a specific point within the Control-pulse-generator.vi

I've attached the full program if anyone wants to take a look!

Thanks!!