DAQmx sampling point on chart

[adriano08]

Hi all,

I have done a Continuous Samples on DAQmx Timing (Sample Clock).vi with setting of sampling rate at 100hz & 10 samples per channel.

When execute the read, the waveform chart does not show 10 samples point per second.

I tried using num of waveform samples.vi to check, it does show 10 samples.

How do I make it, for example, having 10 samples/second on the chart?

[GerdW]

Hi adriano,

reduce sample rate to 10Hz (aka S/s)…

[adriano08]

Hi GerdW,

I reduce to 10Hz and it did show 10S/s.

But I read for somewhere:

it is recommended that the number of samples be 1/10th the rate specified on the DAQmx Timing VI.  For example, if the rate input on the DAQmx Timing VI is 1000 (Hz), then the number of samples per channel on the DAQmx Read VI should be no more than 100.  This is to ensure there are not PC buffer overwrite or underwrite errors.

So for my case, a setting of 10Hz for 10 samples per channel, is this the correct way to do it?

Thanks.    

[GerdW]

Hi Adriano,

But I read for somewhere: it is recommended…

Yes, but with this recommendation you will have chart updates each 0.1s!

So for my case, a setting of 10Hz for 10 samples per channel, is this the correct way to do it?

When you need 10 samples per second and just one chart update per second: yes.