12-23-2009 09:28 AM
Hello,
I found the following example in order to make Frequency Response measurements (SVXMPL_Averaged Frequency Response (DAQmx).vi).
This Vi works on my computer.
In order to adapt this Vi to a pressure acoustic measurement (and not a voltage measurement as in the example) , I built other Vi, but even if I use the same structure as in the example, I have an error (error 200621 : Onboard memory insufficient due to bus bandwith limitation...etc...)
I tried to modify property nodes of the output channel, to modify the buffer size....but nothing worked. I do not understant why it works in the example and not in my program.
I posted my Vis and controls in the attached zip file (Labview version 2009, main Vi is : test_all.vi)
I hope someone can help me to find the solution, or at least to understand why it does not work.
Thanks in advance.
Mathieu
12-23-2009 11:48 AM
Hi,
after some tests, I think that my problem is due to the time of the For loop. For the 1st iteration, the time of the loop is around 200 ms and 3000ms for the 2nd iteration.The error occurs during the 2nd iteration.
I measured time for the Vi in the loop and there are a big differences for the "DAQmx Read" task.
For the 1st iteration, I just read some samples corresponding to DUT propagation delay (500 samples for example).
For the 2nd iteration, I read one block size (for example 3 seconds at 51,2 kHz as sampling frequency so 153600 samples)
In the zip, there are the Vi with the timing function included.
Thanks a lot for helping me.
Mathieu
12-28-2009 07:42 AM
Hi Mathieu.
Could you attach the files :
Gating Settings.ctl
FRF_Stettings.ctl
to open your VIs.
Thanks.
Regards.
Romain D.
National Instruments France
01-04-2010 03:27 AM
Hi,
Thanks for your answer and happy new year !
Here are the 2 commands.
Mathieu
09-06-2018 03:53 PM
I have a Hydrophone (TC4013 from RESON), I am wondering that which type of Data Acquisition do I need to get raw data.