DAQ task update during running task

Hi,
I hope sombody can answer this question.
Is it possible to update a running DAQ task without stopping the task?
In my task I have an analog output and I want to change the amplitude and/or the duty cycle of the output waveform.
Stopping the task and starting again with new parameters needs to much time.
Thank you,
Robert

If you're just looking to write new data to the task then there shouldn't be any need to restart it (you can use AO with non-regeneration like DianeS mentioned). I wanted to make sure to mention that we have an online example that does just this:
Update Multiple Channels of Analog Output On-The-Fly
Additionally, there are some properties that are settable while the task is still running (e.g. AO Sample Rate can actually be changed on-the-fly on many of our Multifunction Boards). Other properties (e.g. AO Voltage Range) cannot be modified without first stopping the task. If you need to stop the task and reconfigure, Ben's method is a good idea. I am aware of an example that does this for Analog Input tasks but I don't think we have one for AO. Here's the link to an AI version in case anybody is interested (unlike AO, the AI Sample Clock is not changeable on-the-fly):
Switching Between Multiple Analog Input Tasks in DAQmx
From what it sounds like, the first link should be exactly what you need and you shouldn't need to worry about restarting your task. Just add Duty Cycle to the control cluster and wire it into the
correspnding input of the Basic Function Generator. If you have any questions about it or run into any issues don't hesitate to let us know!
Best Regards,
Message Edited by John P on 03-25-2010 06:35 PM
Message Edited by John P on 03-25-2010 06:36 PM
John Passiak

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Attachments:
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DAQ task update during running task

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