Retriggerable AI hanging and missing triggers on restart

[Phamton]

Here's a screenshot and the VI for using the AI to acquire the trigger and pulse train.  Note I had to slow down the pulse train frequency because previously I had been running at the maximum AI sample rate.  I tried to modify the program I've been using as minimally as possible.

Paul

[BrowningG]

Hello Paul,

Thanks for your reply and for the VI.  I will use this to try to recreate your issue and see what modifications to your code I can suggest.

[Phamton]

Any luck yet in reproducing my problem BrowningG?  Thanks,

Paul

[BrowningG]

Hello Paul,

I am still trying to find where this issue is occurring.  I should have an answer for you in the next few days.  Thanks for being patient.

[BrowningG]

Hello Paul,

One odd thing I noticed is that sometimes I can get the LabVIEW shipping example Multi-Function-Ctr Retrigg Pulse Train Generation for AI Sample Clock to miss triggers when using certain combinations of trigger rates and sample rates that should work according to the specifications of the card.  Since your VI is based on this example, I feel that these issues can be related.  I have found that removing the DAQmx Configure Input Buffer VI from the task configuration, which makes DAQmx automatically configure the input buffer, eliminates this "hanging" behavior.  I am not sure what causes this, but I have shown the issue to R&D and as soon as I find anything out I will post a reply to this forum to let you know.  Please let me know if removing this buffer configuration helps. 

[Phamton]

Hi Browning,

  Sorry for the slow response; I hadn't noticed your latest response.  I tried eliminating the DAQmx Configure Input Buffer and it didn't appear to help (results from the test vi I posted earlier were similar).  Any word from R&D?  I've been able to ignore this problem during development of my program since it happens relatively infrequently but recently I've gotten to the point where I'm running my data acquisition for long periods of time and have noticed it hanging every once in a while so it is starting to be problematic...

Message Edited by Phamton on 02-04-2008 03:26 PM