Problem with Analog Outputs(NI-Multifunction DAQ PCI-6115 S-Series )

[Reddy JS]

Hi,

I have some queries regarding waveform generation on Analog Outputs
CARD : NI-Multifunction DAQ PCI-6115 S-Series

1) At what resolution can I setup the Update Rate in my application?
2) Can I setup the update rate of 2.001MS/s and 2.002MS/s?
3) I want to generate waveform(Sine) with frequencies from 80KHz to 90KHz in steps of 1KHz, is it possible?


When I tried to generate waveform(Sine) of frequency 80KHz with update rate 3.2MS/s and Buffer count 40,I observe 83.33KHz frequency waveform.

Based on the formula given in documentation supplied by NI: Frequency=UpdateRate/BufferCount


4) At what resolution of frequency i can generate analog waveform(Sine)?


Regards
Reddy JS

[AlanArmstead]

Hello Reddy JS,
I'm not quite sure what program you are using, but give this one a try. You might have better luck.
-Alan A.

[Reddy JS]

Hi Alan,

Thank You for your response,

i am sorry , i forgot to give that which programming language i am using.
i am using VC++.


Regards
Reddy JS

[AlanArmstead]

Reddy JS,
You might want to try changing around the sample rate and buffer size. For example, sample rate 1.6M and buffer size 20, or sample rate 800K, buffer size 10. Keep in mind 3.6M is faster than you can go with both channels (2.5MS/s max update rate with two channels) and approaching the max update rate for one channel, 5MS/s. Also, I found some other VC++ analog output examples. You might want to look through those. Hope this helps!
-Alan A.