Speedup start of measurement for cDAQ-9188

[Gasser]

Hello,

I'm using a cDAQ-9188 with 9205 in order to acquire some different IA signals.

Everytime I want to acquire signals on one channel I reserve the 9205 device and then start the task to acquire finite samples.

My problem is that the start of the task takes 1 to 2 seconds, is it possible to preapare the task in order to speedup the starting of it ?

Thank you in advance for the support.

Greetings

J-D Gasser

[bstreiff]

If the parameters of your acquisition don't change between runs, you can reuse your task by calling start/stop on it multiple times. Additionally, you can explicitly commit your task before you start; this will move the task back to the 'committed' state when you stop. You do this with DAQmx Control Task.vi with the 'commit' action (in LabVIEW) or DAQmxTaskControl with the action DAQmx_Val_Task_Commit (in the C API).

Here's a simple example in LabVIEW that starts a task five times to acquire data. (You could change this to acquire on a button press or some other event, this is just for demonstration purposes.)

Doing some rough off-the-cuff benchmarking, on my system, the DAQmx Start Task VI takes around 20% (66.1ms) as long with the explicit-commit as it does without (329.3ms).

For more information, search the DAQmx Help for the article entitled Explicit Versus Implicit State Transitions.

[Pixar]

Hi J-D

I think your question is very well answered, so if you have any further questions please feel free to post them here.

Kind regards

Pixar

NI AE

[Gasser]

Hello,

thank you for your fast answers !

I will test your purpositions and keep you inform about the results in this thread.

Greetings

J-D Gasser