IVI_Scope Read more than 32767 points

[E.Boivin]

Hi TestStand Developers,

I need to perform a read measurement with TestStand / IVI_Scope Read and a PXI-5922 /32 Mbytes but when I ask for more than 32767 "min num points" I encounter the following error :

Error, Error executing substep 'Post'. An exception occurred calling 'RunStep' in 'ISubstep' of 'TestStand Ivi Step Types' An error occurred while executing the step. VB Error: The IVI Read operation failed on channel 'CH0' for logical name 'ScopeDiff'. Details: An error occurred while attempting to save measurement data to property 'Step.Result.Reading'. Source: TSIviStepTypes [Error Code: -2146828282, User-defined error code.

I don't have such a problem when I'm using LabVIEW.

Is it possible to push the IVI/TestStand limit of 32767 point or is there any solution to by-pass it.

I have tryed to use several niscope_32.dll functions like "niScope_Read" or "niScope_ReadWaveform" but it seems not very easy to get the data array back.

Could you please help me to avoid using only LabVIEW libraries ?

Thanks in advance,

      Emmanuel

[Scott_Richardson]

Emmanuel -

This appears to be a bug in the IVI step types code. There is code that attempts to normalize the array dimensions for the array in the TestStand result and it uses a VB CInt() macro instead of CLng() macro when determining the upper array bound from the string returned from GetDimensions API call.  What version of TestStand are you using?

[E.Boivin]

Hi Scott,

I'm using TestStant 3.0 and I have tryed to use IVI_Scope modules in TestStand 3.5 too (without success) ; and for your information, I'm using NI-Scope version 3.0 / Windows XP SP2 / Max 4.0 / IVI Compliance Package 2.3 / IVI Driver Toolset 2.0.

I hope, this will help you to find the "bug".

Best regards,

   Emmanuel

[Scott_Richardson]

Emmanuel - I have placed a rebuild of the TestStand 3.5 TSIviSteps.dll file under ftp.ni.com/outgoing/TSIviSteps.zip . It contains a change to fix the problem. It should work with TestStand 3.1, but I have not tested it. Please let me know if this fixes the issue for you.

[M.Blanchard]

Hi Scott,

I write on behalf of Emmanuel.

I tested the new DLL under TestStand 3.5, it is ok. We can exceed the limit of the 32 767 points. Consequently, we can reach the limit of 1 048 576 points ( limit of the tables size under TestStand).

Thank you to have placed this new DLL at our disposal, by hoping that it will be integrated in next TestStand.

Best regards,

    Marc

[Scott_Richardson]

Marc -
Thank you for letting me know that it works.  The fix is already in our code base so a future release will have it.

I am curious, does the TestStand array limit size cause a problem for you?

[M.Blanchard]

Hi Scott,

TestStand array limit size isn't a problem for us. It was right an observation on the size of the arrays under TestStand.

Best regards,

    Marc