The N samples mode with triggering on VI Logger Lite is not working

[tiagormendes]

Hello,

I am using the latest VI Logger Lite with a NI USB 6259 32 inputs and I have set the N samples (50 samples) mode with a trigger of 200mv (increasing) in one of the channels. When I am in the "Task Edit" tab, the little preview shows that everything is alright (the signal is refreshed everytime the trigger is activated). My system is connected to a wave generator, so I am supposed to have a signal every 15 seconds or more. But when I click on ok, and I run the task, VI Logger only registers one signal (the 50 samples) and then it ends the task, even though the signal is still there to activate the trigger.

I do not want to use it in continuous mode, I just want to register around 50 samples (at a sampling rate of 10 Hz) every time the trigger goes off.

Can anyone help me, please?

Thanks,

Tiago R.

[Joeri_Wingelinckx_NI]

Hello,

The behavior you see is normal in VI Logger.  VI Logger is "missing" the "while loop" around the task.  

In your case: if you ask a N number of samples to acquire, well that's what you get and the task stops.

But there is a much better alternative for your application which is LabVIEW Signal Express.

LabVIEW Signal Express is also a configuration based application like VI Logger, but build on LabVIEW technology.

The Lite edition also comes for free with the NI-DAQmx driver so it's fully supported for your USB-6259.

You can download it from here (login with you NI.com user profile may be necessary).

https://lumen.ni.com/nicif/us/evalsignalexpress/content.xhtml

The advantage of LabVIEW Signal Express is that you can run your application "Continuously".
So each time you get the trigger, Signal Express will acquire the number of samples configured and wait until the next trigger to start over again.
Just like VI Logger, your data can be stored on the hard drive and exported

Message Edited by Joeri on 06-08-2009 02:32 PM