Example C# code for VXI-MXI-2 interface

[Pradeeban]

I am developing a Test station using VXI based systems.

I am using Agilent E1401B Mainframe, with NI VXI-MXI-2 card.

I have never done any rogramming with VXI systems before, so to start, I write a simple code to read " *IDN? " from the cards installed in the mainframe.

I am using C# 2010 to develop the whole system.

Heare is an example code I wrote to access the VXI cards installed and try to read IDN?.

But it gives an exception "The given session or object reference does not support this operation.."

using Ivi.Visa.Interop;

namespace VXI
{
    class Program
    {
        static void Main(string[] args)
        {
            ResourceManager ioMgr = new ResourceManagerClass();
            string[] resources = ioMgr.FindRsrc("?*");
            FormattedIO488 instrument = new Ivi.Visa.Interop.FormattedIO488Class();
            instrument.IO = (IMessage)ioMgr.Open("VXI0::1::INSTR", AccessMode.NO_LOCK, 1000, "");
            string cmd = "*IDN?";
            instrument.WriteString(cmd, true);
            string responseString = instrument.ReadString();
            try
            {
                instrument.IO.Close();
            }
            catch { }
            try
            {
                System.Runtime.InteropServices.Marshal.ReleaseComObject(instrument);
            }
            catch { }
            try
            {
                System.Runtime.InteropServices.Marshal.ReleaseComObject(ioMgr);
            }
            catch { }
        }
    }
}

Please someone help me to kickstart this VXI interface with Visual C#.

I am stucked here and dont know what to do next. searched all over the internet and couldnt find a good reference for C# in this problem.

could some plese help me with a sample code to read IDN of card installed in the VXI mainframe, with VXI-MXI-2 interface.

BR,

Pradeeban

[nyc_(is_out_of_here)]

.NET 4.0 examples are located at C:\Users\Public\Documents\National Instruments\MStudioVS2010\DotNET\Examples

.NET 4.5 examples are located at C:\Users\Public\Documents\National Instruments\MStudioVS2012\DotNET\Examples

These examples are installed when you install NI-VISA on your computer.

Not sure if there are anything specifically for VXI

[Pradeeban]

Hi Thanks For the reply.

I already tried those examples, but none of them explains me how to connect through VXI-MXI-2 interface and read from VXI device.

In the Measurement and Explorer I can see all my devices are listed.

Ex: VXI0::1::INSTR (VXI-MXI-2)

       VXI::112::INSTR(HP E1466)

I want to talk to one of these device and get *IDN.

I use some example codes to using SCPI commands.

but is responds, like "ERROR = The given session or object reference does not support this operation./n"

please help.

[nyc_(is_out_of_here)]

I haven't used MXI-VXI-2 in a while.

You might want to try http://www.ni.com/support/vxi/interactive_tools/int_comm_tools.htm

before programming in C#

EDIT:

You might want to check that you have the latest driver appropriate for your OS. http://digital.ni.com/public.nsf/allkb/63E23F33EB70A086862571EA00659E04

You might have to re-install the NI-VXI drivers to include support for .NET

[Pradeeban]

Hi,

This link seems to be quite informative. Thank you for sharing this.

From this I understood that the devices i am usung are truly Register based, on which I was trying message based communication.

I ll try to do some register based opeartions.

Thanks.

🙂