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daq write analog output DC value

Hello you all.
This is the first time I use the Analog Outputs of my DAQ board, and I have some doubts.
What I am doing, it to obtain a numeric value, then generate a DC waveform, and then put this waveform in a channel. (see attached vi). This vi is run each one second, as part of a while timed loop, putting values in the DAQ Analog Output each 1 second.
Everything seems to work ok, but when I built the application, and I let it run continuously about 2hours, I get an exception from LabVIEW: "Exception ocurred within the external code called by a call library node. VI XX was stopped at node 0x4D8 of subvi "DAQmx write (Analog DBL 1Chan NSamp).vi"
What is the problem, how can I solve it??
Thanks in advance...
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Message 1 of 2
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Hi Esther,

I have reproduced your exception one time and after without any problem.

On your code, when you want to generate a DC value on analog output, directly you can do it without using Simulated Signal Express.vi. You can wire the Data control directly on Daqmx Write.vi and the Daqmx Write.vi has to be as Analog DBL 1Channel 1 Sample. If you put Simulated signal Express.vi, you´d be able to use more resources and this is not useful for your application.

Moreover, on Daqmx write the "auto start" is true by defect, you don´t need the Daqmx Start Task.vi due to the auto start will begin the task.

I send your code with these modifications and test it with/without the daqmx start task.vi.

I hope this help you

Diego M.

PD. By the way, after using Daqmx Stop task.vi is interesting to put an error out.
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