I want to control sampling of analog output using Ni 9263 and fpga crio

[wgkotb]

I  generated sinusoidal signal using NI 9263 analog output with fpga node but i need to generate the signal with specific sampling frequency 1000 Hz or 0.001 sampling rate

[Rob_Ward]

Dear wgkotb,

thank you for your post.  I looked at the datasheet for the NI 9263 ( https://www.ni.com/en-us/shop/model/ni-9263.html ) and it says the module has a 100kS/s update rate.  It doesn't look like the module goes that fast bud.

Hope this information helps.

Kind Regards,

[wgkotb]

Dear Robert Ward,

Thanks for your reply,

If I understand what you mean, I can acquire upto 100000 Sample per sec with the module?

but i need t acquire only 1000 Sample/sec.

How to do that?

Regards

[Rob_Ward]

wgkotb,

Sorry, I mis-read your original post; your module does have a fast enough sampling rate.  You can do this with a timed loop.  Go into your functions palette and select Structures -> Timed Structures -> Timed Loop.  You can set the clock as the 1kHz clock and set dt as 1ms.  You can push the data to the Analogue Output of the module using a shared variable inside the timed loop.

Do you have any sample code or screenshots of what you have so far so I know where you are up to?  Have you seen this tutorial on developing custom measurement and control I/O hardware with the LabVIEW FPGA module and reconfigurable I/O hardware ( http://www.ni.com/white-paper/3261/en  )?

Regards,

[wgkotb]

Hi Robert Ward,

thanks a lot for your reply,

I will try to do you solution

Thanks

[Rob_Ward]

Dear wgkotb,

I was able to find this example code that you may find useful; https://forums.ni.com/t5/Example-Code/Create-Timing-Source-with-Analog-Input-Sample-Clock-Using/ta-p... .  Please note there are tons of other example code on the NI Developer Community that you may find useful.

Kind Regards,

[Ivymerciqq]

Hello Rob_Ward,

the sampling rate for 9263 is 100Ks/s. Does the sampling rate share among four channels, which means if I am using 4 channels, the sampling rate is 100ks/s /4 =25ks/s?

Thank you and have a nice day!

[Rob_Ward]

Dear lvymerciqq,

Analogue Output modules in general have one DAC per AO channel, whereas Analogue Input modules have one ADC and therefore require multiplexing  (FYI - ADC components can be rather expensive).  From the looks of it - this C series module should be able to sample at 100KS/s for each channel.

Regards,

[Ivymerciqq]

Thank you.

If it is not described as aggregate sampling rate in the manual, it is for every channel. Is it correct?

[Rob_Ward]

If it is described as "simultaneous" I would understand that to mean that there is one DAC per AO channel as multiplexing would incurr a delay between channels - as is the case with multiple AI with only one ADC.

Kind Regards,