In simultaneous measurement with AI and AO, I used PXIe-6124 which supports timebase clock of 80MHz.I was told I can use 80M/n(integer) as a sample rate in PXIe-6124.In order to get n is integer, I limited my parameters to 2 and 5 common factors. But, why the actual sample rate is different to the input sample rate, 1.6MHz (n=50).The actual rates are 1.67E+6 (analog input) and 1.54E+6 (analog output). What's wrong for this problem?Any other to consider in making the sample rate? labmaster.

Hi labmaster, It sounds like you're on the right track--to address your questions:0) The counter tasks can use the 80 MHz timebase (20 MHz and 100 kHz are also available). So, the available frequencies you can generate using the counter is 80MHz/N, where N is an integer (between 4 and 2^32). You are still limited to the divide down method, but you would be working with a higher timebase so you could achieve frequencies that you couldn't otherwise (such as 1.6 MHz). 1) You can check the actual sample rate of the counter using the following property node: 2) You may run the AI, AO, and two counters simultaneously in seperate tasks -- I would start AI, AO, and Ctr2 before Ctr1 so that all the tasks will start simultaneously. If you started Ctr1 first, then the clock would be running so the tasks would start at different times (based on the software) unless you were using a trigger to start them.I'm glad to hear that this has been helpful for you--I hope all is well and the best of luck to you with your application! -John

LabVIEW

divided timebase

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Thanks so much, John.

I wrote the source of counter explicitly. It works.

labmaster.

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LabVIEW

divided timebase

Re: divided timebase