Sampling Analogic Signal cRIO 9201

Hallo,
I succed to achive analogic signal and to create fpga and host program for cRIO 9004 and Analogic input module RIO9201!
I achive very well a 1 Hz signal but when I increase frequency of my signal I lose in resolution!
the sampling rate of module is 800KS/s and I don't understand if it is a problem of time in my software!
in the example of NI web site it isn't clear!
Thank you
Marco
Attachments:
provaanalogico.zip ‏98 KB

Thank you, Alessio!
I call Nationale Support but they still recall me!
I follow the step in Tutorial High Speed Continuous Buffered Data Acquisition.
...........and there is a problem with FIFO, I mean!
because the the led empy is always turn on and the FIFO read doesn't work!
I know that four value enter into FIFO write but FIFO read doesn't read them!
I believe the problem is here!
could you help me another time?
Thank you

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Have things changed over the years?
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Attachments:
acq_and_graph.zip ‏165 KB
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Message Edited by _Pavel_ on 05-23-2007 09:06 AM
Attachments:
Progr.zip ‏80 KB

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I am new to the sight and look forward to participating. I have a project that I’m working on and I would like to ask for your thoughts and direction if you’re willing. I have a few weeks left before completing an electronics program degree and Labview is one of the classes. The project I have chosen is to illustrate the differences between a micro controlled system and Labview controlled environment. I will be acquiring a signal through a ultra sonic distance sensor. The analog signal will be produced after which acquired through a SCB – 68 connector block and converted using the pci-mio-16E. The sensor operates at 40 kHz emitting a 5v pulse (burst) then falling to gnd for a short period followed by a 5v rise and staying high for a period of time waiting for the return of the frequency. This time period represents 3 inches to 27 ft in distance. I would like to interact with this signal through the distance period (portion) and output a string displaying a numeric value of the distance on the front panel obtained from an array built from different periods of the signal. I am not clear on what Labview function offers this type of control. I am hopeful in utilizing a vi or some type of trigger that allows me to build an array produced by some math functions. Any help would be appreciated.
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First thank you for your response, I will have an opportunity to make a capture tomorrow in class. I believe I have run across the waveform measurement VI in my searches and am sure it’s a very good choice. The trigger VI you suggest, going by the name, should be my ticket. Would you imagine a delay or decreasing time after the capture, allowing the trigger VI time to respond to an output configuration be required?
If I remember correctly the sampling rate capabilities are 500K samples/ second with 12 bits of resolution and as I say that it seems some of the capabilities rely on the processing speed of the computer. I guess I will kick the tires tomorrow hey. There are 2 class periods remaining to finish our projects @ 2 hrs / class and my anxiety is a bit high. Wish me luck and thank you so much.
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Sampling Analogic Signal cRIO 9201

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