NIMAX/Labview IVI.NET Issue

[refi1]

I bought a rohde&schwarz NGE103B Power supply and want to control it via IVI/Labview. Rohde&Schwarz offers a IVI.NET driver (RsHmc804x-ivi.net-x64-1_5_1_0.msi). After installation MAX lists the instrument driver module (see MAX1).

In MAX I added a IVI Logical name and a driver session which points to the instrument driver module. In Labview the logical name doesn't appear in the control when the class is set to "IviDCPwr". When no ivi class is selected the logical name appears. The reason for this is that there are no entries in the MAX for Published APIs. When I add a API for "IviDCPwr" (Version 1.0, IVI.NET) the logical name in labview appears when the class ist set to "IviDCPwr".

But when I try to initialize the device (see Labview1) I get a labview error:

"Error -1074134949 occurred at IviDCPwr Initialize With Options.vi

Possible reason(s):

Primary Error: (Hex 0xBFFA005B) File not found."

I'm using Labview 2017 and IVI Compliance Package 17.0.

Does labview support the use of IVI.NET drivers? Did I miss something?

[MM_RohdeSchwarz · Accepted solution]

Hi ReinholdFink,

R&S IVI drivers are of .NET type. LabVIEW only works with IVI-C drivers. But.... there is a way... 🙂

You need to do 2 things:

- Install IVI.NET adapters from NI: http://www.ni.com/download/ivi.net-adapters-1.0/6239/en/

- Copy the attached manifest file (unpacked) to the folder where your LabVIEW.exe is, usually:

"c:\Program Files\National Instruments\LabVIEW 2017"

The manifest file tells LabVIEW to use the .NET assemblies built with the .NET framework 4.0 - all the R&S IVI.NET drivers are built with the .NET framework 4.0

Afterwards you can use our IVI.NET drivers in LV

Cheers

[refi1]

Hi MM_RohdeSchwarz,

thank you very much for the help. I can now communicate with the device over the ivi driver but now I have a new problem. The returned measure values are scaled wrong. When I have 11V as output voltage the device returns a measurement of 11e+6V the same happens for the current (100mA -> 100e+3A (measured)).

I think the problem is the decimal point but I can't change it because I only have access to the double value which is returend from the ivi VI.

[Albert.Geven]

Hi

You can change the default in LabVIEW by setting use localized decimal point to False.

In options localized decimal point

[refi1]

Hi

I tried the localize decimal point option but unfortunately it didn't change the result.

[Albert.Geven]

Did you see the * at the end of the text in the options.

This means that you have to restart LabVIEW before it is recognized....

[refi1]

Hi Albert Geven,

yes I restarted LabVIEW after enabling and disabling the option. I think the IVI DLL which returns the value is not effected by this option.

But thank you for your effort.

[refi1]

I solved the problem by changing the windows 10 system decimal separator.

[MM_RohdeSchwarz]

Hi ReinholdFink,

glad to be of help. Regarding the decimal point - setting of the LabVIEW decimal point has no effect, since the value already comes as double from the driver itself. We will fix the driver to work correctly independently from the Windows regional settings. The fix comes out in the next 2-3 weeks.

[MM_RohdeSchwarz]

Hi, the fix is now online: https://www.rohde-schwarz.com/de/treiber/hmc804x/