Jump to content

SciWare GOOP + DAQ task = task disappears


Recommended Posts

I have been trying to create a channel with DAQmx Create Channel (AI-Voltage-Basic) in a Sciware GOOP class. The DAQmx gives me a task, which I start and then direct the task to the appropriate data member of the class. So far everything goes fine.

However, when I retrieve the task from the data member to acquire a voltage value, I get the following error:

Error -200429 occurred at DAQmx Read (Analog DBL 1Chan 1Samp).vi

Possible reason(s):

Measurements: Value passed to the Task/Channels In control is an empty string (or I/O control).

The value must refer to a valid task or valid channels.

So where did the task disappear?

Please, see the attached code.

DAQmx_task_test.zip

Link to comment

I do not know much about SciWare's GOOP, but any refnum or resource (like a task) that is created in LabVIEW is automatically disposed when the *top-level* VI that created it goes idle. Is it possible that you are creating the DAQ task in some VI that is being called using the Run VI method of VI Server, and that VI is going idle and thus throwing out the newly created task?

Link to comment

Is it possible that you are creating the DAQ task in some VI that is being called using the Run VI method of VI Server, and that VI is going idle and thus throwing out the newly created task?

I'm not quite sure when subVI is in a idle state, but the SubVI that creates the task goes into "SubVI waiting to run"-state. But how can I make a subVI not to go idle when exiting from a subVI?

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Unfortunately, your content contains terms that we do not allow. Please edit your content to remove the highlighted words below.
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.