LabVIEW

cancel
Showing results for 
Search instead for 
Did you mean: 

Need to sample at 1000 Hz

Hi guys, Im hoping to set my sampling rate to 1000 Hz but I cant figure out how. I recently changed the  acquisition mode from "N samples" to "1 Data point (On Demand)", and it increased my sampling rate to somewhere near 1700 Hz but it is important I lower it to 1000 Hz for post-processing purposes. I tried adding a "wait till next ms multiple" button to slow it down, but when this was set to 1 ms I only sampled around 500 Hz  (versus the 1700 when it is 0). Is there any way to set the sampling rate to 1000 Hz?

 

Attached is the main VI and the only subVI that I believe is relevent, as it includes the DAQ assistant.

 

Thanks!

0 Kudos
Message 1 of 4
(825 Views)

Hi Benny,

 

when you want to have 1000 Samples/sec you need to use DAQmxTiming. Using "1 sample on demand" you will never reach your goal…

Which hardware do you use?

 

General comments:

- Clean up your VI.

- Remove local variables. All of them. Use wires! THINK DATAFLOW!

- Never delete the label of controls. Never do that! Hide the label in the FP when it conflicts with your FP "look and feel"… 😄

 

This is just silly:

check.png

THINK DATAFLOW!

Best regards,
GerdW
CLAD expired, using LV2011SP1 + LV2017 (+LV2019 sometimes) on Win7+cRIO
Kudos are welcome Smiley Wink

Message 2 of 4
(819 Views)

Thanks for a speedy response!

 

I am sending signals from an LVDT and load cell into the Daq board. Can I use the Daqmx alongside the Daq assistant or would I have to manually build my on Daq VI (which I have no clue how to do)?

 

edit: Note, I recently inherited this VI and am not 100% familiar with its functionality. I only understand the basics of labview and this is a bit uot of my league

0 Kudos
Message 3 of 4
(808 Views)
Highlighted

Hi Benny,

 

you did not answer my question! Which DAQ device do you use?

 

Please post qeustions here in the forum. PMs are not the right way to discuss generic LabVIEW questions.

 

In trying to manually assemble the DAQmx (without the assistant), what steps should I take? Where should I start, and is there any way you could possibly list the order of DAQmx blocks I would need to make a successful VI?

You should start here and then you should check all those DAQmx example VIs in the ExampleFinder!

 

Can I use the Daqmx alongside the Daq assistant

Well, you could mix them. I suggest to use just basic DAQmx functions and to stay away from DAQAssistent.

Best regards,
GerdW
CLAD expired, using LV2011SP1 + LV2017 (+LV2019 sometimes) on Win7+cRIO
Kudos are welcome Smiley Wink

0 Kudos
Message 4 of 4
(754 Views)