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Repeat outputs with analogoutput without requiering to use putdata repetadly

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Hi all!
I've got my analogoutput channel working as I want. When it receives a digital trigger on line PFI1 it starts the function that I loaded.
ao_Ref = analogoutput('nidaq','Dev1');
addchannel(ao_Ref, [1]);
putdata(ao_Ref, xt);
However once its started (and finished) the "buffer" on the nidaq card is empty. Triggering again doesn't do anything. Currently, I need to reload the data on the card by repeating the whole code.
Surely there is a much more efficient way to make it output the same data every time the trigger is activated.

Accepted Answer

Walter Roberson
Walter Roberson on 22 Sep 2011
No there isn't, not unless your hardware supports storing a buffer of data and sending the buffer on request. Which some hardware does, but most does not.
Walter Roberson
Walter Roberson on 26 Sep 2011
I would need to research that; I am not familiar with how to program those devices, such as to construct the waveform buffer.
Which model device are you using?
Michael Leung
Michael Leung on 9 Nov 2011
NI 6259.
I never managed to get it to work, so I moved this part of the code to a micro controller.

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More Answers (2)

Manisha on 26 Sep 2011
Hi Micheal,
Have you looked at the property TriggerRepeat?
Regards, Manisha
Michael Leung
Michael Leung on 26 Sep 2011
No, I have not. I was hoping that something like this would exist. I'm getting an error message now.
(I placed this line of code after the HwDigitalTriggerSource)
??? Error using ==> daqdevice.set at 261
Invalid property: 'TriggerRepeat'.
Error in ==> Ramp at 26
Michael Leung
Michael Leung on 26 Sep 2011
Hmm it seems its only applicable to AI (Analog Input) channels.
I'd need it for Analog Output

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signal on 9 Nov 2011
where num is an integer or inf for continuous output.

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