topic Re: WaitOnEvent Timing out in Measurement Studio for .NET Languages

WaitOnEvent Timing out

master9991 — Wed, 06 Jan 2016 17:55:55 GMT

Hi All

Trying to set SRQ for power meter (HP437B) via USB GPIB VISA and waiting for event to return.

When the same thing is done in VB6 it works.

Under given is the code snippet in C# 2010

_gpibSession = null;
_gpibSession = (MessageBasedSession)ResourceManager.GetLocalManager().Open(_resourceName, AccessModes.NoLock, timeOutValue);

_gpibSession.SynchronizeCallbacks = true;
_gpibSession.Timeout = 60000;
_gpibSession.DefaultBufferSize = 65536000;

_gpibSession.TerminationCharacter = 10;
_gpibSession.TerminationCharacterEnabled = true;

_gpibSession.Write("*SRE 64");
_gpibSession.EnableEvent(_mbSrq, EventMechanism.Queue);
_gpibSession.Write("PR");		//preset
_gpibSession.WaitOnEvent(_mbSrq, 6000);          //timing out at this point

StatusByteFlags sbfStatus = _gpibSession.ReadStatusByte();

if ((sbfStatus & StatusByteFlags.RequestingService) != 0)
{
   MessageBox("Request Service in the status register is set.");
}
else if ((sbfStatus & StatusByteFlags.MessageAvailable) != 0)
{
   MessageBox("MAV in the status register is set.");
}
else if ((sbfStatus & StatusByteFlags.EventStatusRegister) != 0)
{
   MessageBox("ESB in the status register is set.");

   string esrValue = _gpibSession.Query("*ESR?");      //get content of event status register
}

Any help in resolving this issue is appreciated.

Thank you

Re: WaitOnEvent Timing out

nyc_(is_out_of_here) — Wed, 06 Jan 2016 18:41:21 GMT

According to the documentation, WaitOnEvent method will throw an exception after the timeout you in put in.

Are you getting an exception that is thrown?

Re: WaitOnEvent Timing out

master9991 — Wed, 06 Jan 2016 22:45:33 GMT

Yes I'm getting an exception that is thrown as given under

"Timeout expired before operation completed. VISA error code -1073807339 (0xBFFF0015), ErrorTimeout"

Re: WaitOnEvent Timing out

nyc_(is_out_of_here) — Wed, 06 Jan 2016 23:21:44 GMT

Where did you get this code snippet?

NI has very good examples on Servest Request written in .NET 4.0 and .NET 4.5

You basically register the handler for the event.

Look in C:\Users\Public\Public Documents\National Instruments\NI-VISA\Examples

Re: WaitOnEvent Timing out

nyc_(is_out_of_here) — Wed, 06 Jan 2016 23:53:40 GMT

One thing you should note is that TerminationCharacter is for read *only*.

You will need to add your own when writing to the instrument.

Re: WaitOnEvent Timing out

master9991 — Thu, 07 Jan 2016 17:11:59 GMT

Ok I checked for NI-VISA examples and only found C & VB6 code.

Re: WaitOnEvent Timing out

nyc_(is_out_of_here) — Thu, 07 Jan 2016 17:21:49 GMT

@master9991 wrote:

Ok I checked for NI-VISA examples and only found C & VB6 code.

Then you need to re-install NI-VISA.

I highly suggest appending NewLine to your VISA write.

Re: WaitOnEvent Timing out

master9991 — Thu, 07 Jan 2016 17:45:19 GMT

Already did the re-install and have the new line when ever a write is done.

Can you send me online link to the NI-VISA .NET examples.

Re: WaitOnEvent Timing out

nyc_(is_out_of_here) — Thu, 07 Jan 2016 17:58:13 GMT

@master9991 wrote:

Already did the re-install and have the new line when ever a write is done.

Can you send me online link to the NI-VISA .NET examples.

There aren't online examples that I know of.

When installing you may want to do a custom install. It is suppose to detect that you have VB.NET installed, but you never know...

Let me repeat yet again. You may be timing out because your VISA write is not complete and your instrument is waiting for your termination character.

Re: WaitOnEvent Timing out

master9991 — Thu, 07 Jan 2016 18:16:44 GMT

I am indeed sending the termination character. You check the code I posted above.

_gpibSession.TerminationCharacter = 10;
_gpibSession.TerminationCharacterEnabled = true;

Re: WaitOnEvent Timing out

nyc_(is_out_of_here) — Thu, 07 Jan 2016 18:31:55 GMT

@master9991 wrote:

I am indeed sending the termination character. You check the code I posted above.
_gpibSession.TerminationCharacter = 10;
_gpibSession.TerminationCharacterEnabled = true;

No, you are not. I told you that above which you didn't bother to read apparently.

Re: WaitOnEvent Timing out

master9991 — Thu, 07 Jan 2016 18:39:41 GMT

I sending the same parameters in VB6 and it works.

I have read what you said (given under) but that didn't solve my problem.

"One thing you should note is that TerminationCharacter is for read *only*.

You will need to add your own when writing to the instrument."

Re: WaitOnEvent Timing out

master9991 — Fri, 08 Jan 2016 18:09:30 GMT

Today I tried running the NI-VISA DotNET4.0 example for Service Request

- I am still getting time out when it waits on the "WaitOnEvent" [Synchronous mode] [GPIB-USB-HS with Windows 7 64 bit]

- It never runs the Handler routine [Asynchronous mode] [GPIB-USB-HS with Windows 7 64 bit]

But when I run my VB6 code for the Service Request it runs perfectly [Using a PCI-GPIB Card with Windows XP]

Any help is appreciated.

Re: WaitOnEvent Timing out

nyc_(is_out_of_here) — Fri, 08 Jan 2016 18:19:45 GMT

@master9991 wrote:

Today I tried running the NI-VISA DotNET4.0 example for Service Request

- I am still getting time out when it waits on the "WaitOnEvent" [Synchronous mode] [GPIB-USB-HS with Windows 7 64 bit]

- It never runs the Handler routine [Asynchronous mode] [GPIB-USB-HS with Windows 7 64 bit]

But when I run my VB6 code for the Service Request it runs perfectly [Using a PCI-GPIB Card with Windows XP]

Any help is appreciated.

Run your VB6 code with the GPIB-USB-HS

Re: WaitOnEvent Timing out

master9991 — Sat, 09 Jan 2016 00:13:20 GMT

Ran VB6 code for the Service Request and it runs perfectly [GPIB-USB-HS with Windows 7 64 bit]

viStatus returns "Operation Completed Successfully"