daqmx node relativeTo Most Recent Sample slow loop

[kebitmat_f]

Hello,

I'm reading AI using DAQmx M series device using Continuous Mode. I got an delay in reading loop.

My setting:

NI-USB 6255

AI: 64 CH

Sampling rate: 15kS

Sample per channel: 15

The reading loop should be = 15/15k *1000 = 1ms

However, when using DAQmx node:Most recent sample -> RelativeTo

I got 1 reading loop =10ms.

Even I changed the Sample per channel to 20 or 30, the loop still 10ms.

Could anyone know this issue?

[sunaenae]

Hi kebimat_f,

Do you think you could post a snippet of your code so we can get a better idea of how you're configuring your AI?

Here are some resources for reading an analog input with DAQmx: 

https://www.ni.com/en/shop/data-acquisition-and-control/what-are-multifunction-io-devices/taking-a-m...

https://www.ni.com/en/support/documentation/supplemental/06/learn-10-functions-in-ni-daqmx-and-handl...

Also, make sure you have your DAQmx Open and Close VIs outside of your reading loop.

[kebitmat_f]

Dear Sunaenae,

I attached the VI here. Please check

Thank you!

[sunaenae]

Hi,

What exactly are you trying to achieve with the Relative To property -- what is your end goal in terms of how you want to acquire samples?

It looks like everything is configured correctly from your code.