Continous output signal using DAQ usb 6008 in matlab

Good evening,

I am trying to output a continuous signal using the NI DAQ usb 6008. When using this code:

ao = analogoutput('nidaq','Dev1');

ch = addchannel(ao,0);

putsample(ao,2)

I am sending one sample to the output. Can anyone help me to output several samples and then get a continuous signal?

I have tried the function "repeatoutput" but when verifying the output signal using an oscilloscope, I have nothing.

Thank you in advance

Takoua

[Noor Atifah Nordin]

hye Takuoa,

can i ask you to teach me how you generate data from oscilloscope using usb 6008 ? my prof has ask me to generate signal from oscilloscope using ni daq 6008 in matlab to. i've been out of option on how to do it. does it required the latest version of matlab, because right now i;m using quite old version (r2012a) since i have a laptop with 32 bit only. Can you pleaseeeee enlighten me about this?

Answer 1

[Chirag Gupta]

Hi Takoua,

You can try using the putdata function. You can get more information about it by typing doc putdata on the MATLAB command prompt.

This way you can queue up your data and then continuously output it when you do start(ao)

However, since NI USB 6008 is a basic device, it might not have an onboard clock for analog output and you would then get an error indicating the same. In this scenario, the DAQ board itself does not support continuous output.

A possible workaround might be to use timer function and update your value. You could then theoretically update values every millisecond.

Answer 2

[Takoua]

Thank you for your response. It has worked using a timer object for updating the output value. Thank you again

[mado]

how did you do that ? i faced the same problem