Generate waveforms for a set time lapse

Hello everybody,
I am not an expert in labview, so I am sorry if my question could sound stupid. I am generating 6 different waveform for my NIDAQ, all of them have different frequencies. I would like to be able to select for how long I want to generate them (so, for example, use the frequency of one waveform as a master and generate 10 periods of this waveform). 
I really thank you all if you could help.
Best, 
Giulia

You don't say how you are generating the waveforms.  If you are using a timed loop (running at, say, 1 KHz) and in each loop iteration generating the "next point" of your six waveforms, simply run the loop for as many iterations as you need.  For example, if you want 10 seconds of data, run the loop for 10 * 1000 steps to generate 10 seconds of waveform data.
[This answer sounds like the "answer to the wrong question" -- feel free to clarify your question, perhaps with some example code].
BS

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