Open / connection status

[Jan_K]

Hej.

I am new to C# but have made some GPIB Instrument control in C++ some 10 years ago so I am not a hardcore programmer.

My problem is that I want to open a connection to an instrument and then detect if it is there.

If it is not there then I want exit the function.

I have not been able to figure-out how to get the handle status back.

I have been looking for a handle that is “null” but found nothing.

And I have been looking for “exceptions” and made some “try and error” but without success.

Anyone that can help.

I am using the VisaNS.

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////

using NationalInstruments.VisaNS;

public void Get_IDN(int i)

   {

     string responseString;

     gSession = (GpibSession)ResourceManager.GetLocalManager().Open("GPIB0::20::INSTR");

     responseString = gSession.Query("*IDN?\n");

     gSession.ControlRen(RenMode.DeassertAfterGtl);

     gSession.Dispose();

    }

/Jan

[nyc_(is_out_of_here)]

Look at the examples in C:\Users\Public\Public Documents\National Instruments\NI-VISA\Examples\DotNET4.0\

[Jan_K]

Hej nyc thanks.

I have already been looking on these examples and that was what led me to look for exceptions. More precise I tried to catch "VisaException" but with no luck.

It never registrated any exception though no instrument was connected.

So am I searching in the wrong direction.

/Jan