PXI 6289

[ANTO_R]

Hi,

I am a beginner in LabVIEW and i am using NI PXI 6289 DAQmx card and i wish to do a PWM duty cycle measurement. For that purpose i need to connect the PFI0 to the gate (Ctr0/Ctr1) and source clock as any internal clock. Is it possible to route PFI0 to gate and measure the PWM of the signal fed via PFI0? if so, Kindly explain how?

Thanks,

Anto R

[JKMM]

I am a little unclear on what you are trying to do.  Is your goal to measure the duty cycle of an external PWM signal?  Or do you wish generate a PWM signal from the 6289?  Or do you wish to generate a signal from the 6289, and then measure the signal you generated on the same 6289?

[ANTO_R]

I wish to measure the PWM of an external source. The duty cycle and frequency of the external source are configurable. I need to measure it using PXI-6289

[JKMM]

On the menu within LabVIEW, go to Help>>Find Examples...

In the example browser, double click the "Hardware Input and Output" Folder

Double click the "DAQmx" folder

Double click the "Counter Input" folder

Select "Counter - Read Pulse Width and Frequency (Continuous).vi" 

This example should do what you want.  Just make sure you select the "Pulse Width" tab, and select the right counter input from the "Counter" pulldown.

[Bicbehr]

I'm trying to calculate the absolute accuracy of a 6289 reading. In looking at the example on page 5 of the NI 628X specification the number at the bottom that is calculated for absolute accuracy is 980uV. Is that +/- 980 uv?

[Aaron_W.]

Bicbehr,

I know this thread is referencing the 6289, but your question is completely different than the original question. I would recommend posting a new question in the future. With that said:

Absolute accuracy depends on a number of factors when taking a reading with any DAQ card. I would look at the NI Accuracy Calculator. This will walk you through the expected accuracy for your device.

[Bicbehr]

Sorry to clutter up your forum, but I didn't know where else to put this post. If you have a suggestion let me know. Some times the questions that seem the simplest are the hardest.

[Aaron_W.]

I think the Multifunction DAQ board is a great place to post this question, I would have just started a new thread. No harm, just a suggestion.