Real-Time Measurement and Control

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fft with crio9074

Hi Alll
I am trying to do a fft analysis of a signal acquired from analog input card ni 9205.I have the kit crio 9074 and i am using it in scan mode.
The main problem is that when i connect the fft block with the waveform graph , the graph shows no lines though when i export the value in excel , it has some value, the back window and front window of my vi(running) is attached.Even the indicator shows the value of the signal but i am not able to see anytihng in the graphs.
 Please someone help urgently i need to get it done for my project work

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Message 1 of 7
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The graphs actually are updating but since you're only writing one point, there's not a line. If you change the graph to a chart, it will keep the historical points and add the new point to it. 

Alex Person
NI-RIO Product Support Engineer
National Instruments
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Message 2 of 7
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I understand your point but i am unable to connect waveform chart directly to the output of FFT block.

Can you please suggest me an alternative way of calculating FFT and displayin it on a graph on scan mode of CRIO 9074

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Message 3 of 7
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Either build up points in your array before using the Power Spectrum function or use a different FFT/power spectrum function.

Alex Person
NI-RIO Product Support Engineer
National Instruments
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Hi, I got a cRIO9074 for the vehicle control, I want some global variable saved in the TDMS file, a program as the attachment, after running ,there is no Error Out, and I can see the data flow when running. single-shot operation show no error too, but in the path ‘c:\DT.tdms’, that in the disk C of my laptop, I can not find the TDMS file, No error occur, but I can not find the TDMS file…. Please someone help urgently i need to get it done for my project work 3Q
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Hi, I got a cRIO9074 for the vehicle control, I want some global variable saved in the TDMS file, a program as the attachment, after running ,there is no Error Out, and I can see the data flow when running. single-shot operation show no error too, but in the path ‘c:\DT.tdms’, that in the disk C of my laptop, I can not find the TDMS file, No error occur, but I can not find the TDMS file…. Please someone help urgently i need to get it done for my project work 3Q
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Message 6 of 7
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thank you

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