Analog Software Trigger

[Axel_Manz]

Hello,
my DAQ card (6034E) does not support any hardware analog triggers. Using VB6 I can setup a software analog trigger but I don't know how to do it in VB .NET

The help files are no big help for me, so if someone knows how to do it please help me.

Thanks
Axel

[nd]

Alex,
Are you using Traditional DAQ or NI- DAQmx?
Depending on which one you are using the API calls will be different.

However, just like in traditional DAQ, to setup the software analog trigger you will have to read the incoming data and calculate whether the trigger conditions were met.That logic should not be very different.

Once I know whether you are using Traditional or NI-DAqmx i should be able to give you more specific information about the steps involved..

[Axel_Manz]

Hi Alex,
I'm using the DAQmx. In VB6 I can set the Trigger using:

CWAI1.StopCondition.PreTriggerScans = 50
CWAI1.StopCondition.Level = 1
CWAI1.StopCondition.Mode = cwaiRising

But I can't find something like this in VB .Net

Do I have to scan manualy my data to check for trigger conditions?

[nd]

Hi Axel,
The short answer is ..Yes (but we are working on making it easier)

In traditional DAQ, software analog triggers were not part of the API. However we did make the calculations a part of the VB 6.0 DAQ ActiveX control's API. Internally we would manually check the data for trigger conditions.

In DAQmx, by design, we leave this to the user, in all of our environments, be it .NET, C++, LabVIEW or CVI.
However we are currently working on an example that will show you how to do this and will at the very least get you started.
I will post the example here as soon as we are done, which should be within the next week.

So while the software analog trigger is not part of the API, you will now have the source available, and can modify it
as you see fit. Or of course you could write it yourself too.

Please let me know if you have any more questions or comments.

Nandan Dharwadker

[nd]

Axel,
Here is an example that should help you get started..
As you can see from the example, there is an advantage in having the source code, in that you can skip all the conditions that you don't care about...

Please let me know if you have any questions or comments.