VI gives error 200524

[tuyenhoang7]

When I run the attached VI, which I found the instructions for online, from an university: http://homepages.wmich.edu/~j0stahl/ece2210/Labs/ECE2210_Lab2_PWM.pdf

I get Error 200524, stating that the number of channels in the data does not match the number of channels in the task.

I've tried using different DAQs, 2x 6009 and a 6229, and rewrote the program twice.

What am I missing? Is it the capability of the DAQ, or did I miss anything?

Thank you

[PBP]

Are you writing digital output?

This error occurs when you define, for example 8 channel in task and writing less or higher than 8 channnels in daqmx write VI.

[tuyenhoang7]

Thank you for your answer. 

Yes, digital output. I am meaning to write only 1 channel, but it is giving me the error that I am trying to write 500. I am not sure what to think of that. When I change the frequency when generating the signal inside the program to a lower frequency, the amount of channels I am trying to "write" goes below 500.

Edit: The example I the link provided: http://homepages.wmich.edu/~j0stahl/ece2210/Labs/ECE2210_Lab2_PWM.pdf 

is specifying writing an analog output, so that's what I did. When trying to write a digital output, I get the same error.

[tuyenhoang7]

When looking at the VI I included, if I remove DAQ Assistant, the VI runs fine. Seems like DAQ assistant is trying to write each sample to a separate channel, because when I change from 500 samples to 5000, it wants 5000 channels since there are 5000 tasks. How can I make it so everything goes into 1 channel only? 

[Dennis_Knutson]

There are 500/5000 samples in your waveform and each sample corresponds to a channel. Nothing to do with tasks. You've misconfigured the DAQ assistant and feeding it the incorrect type of data.

[tuyenhoang7]

I am not sure what to do here. Changing it to 1 sample will satisfy the current DAQ Assistant settings but is not the right answer. What did I misconfigure inside the DAQ assistant? I do not know what data to feed it either besides the output of the simulated square signal.

[Dennis_Knutson]

I don't use the daq assistant. I suspect you need a digital waveform or use an analog channel as originally programmed. Neither will work with the 6009, though since it does have hardware timed outputs.

[tuyenhoang7]

What would you, or anybody else, suggest for my given VI? I just want this to run, and add data logging later, with or without the DAQ Assitant.

[Dennis_Knutson]

I would recommend you search for pwm examples that use the counter and use the 6229.

[tuyenhoang7]

Any chance to use it on the 6009? There must be a way