storing data after certain threshold

[shinjita]

Hello

       Ok, I am trying to acquire the frquency generated by the abutment after getting converted by the sensor by a DAQ assistant, then Iam comparing the data(wrong connection earlier on) to a particular level set buy the user, first if the voltage is less  than the min: threshold voltage and then if its true it will check if the voltage is less than the max: threshold voltage, if both conditions are true then the data will be wriiten into the measurement file if not then it is noise. Now there exists an FFT program which i need to use, so I need to call it after the data is stored in the read from measurement file. So I was asking how to call the FFT subroutine?

Regards

Shinjita

[Dennis_Knutson]

And why would you want to call that instead of the Spectral Analysis function? Have no idea where you found that VI but as you can tell, it does its own read from file.

[shinjita]

Hello

       Is there any way so that I can connect the output of the file to the input of the subroutine that is the fft function which I call?

Regards

Shinjita

[shinjita]

Hello

       Also wanted to ask if the program is correct now , that is the bit till storing of the data

Regards

Shinjita

[shinjita]

Hello

        In my program Iam getting the following error:

1. Tunnel: missing assignment to tunnel

2. Case structure: sector values  not unique, but I need to check consequetively if the condition is true then only I can write it in the file

Regards

Shinjita 

[Dennis_Knutson]

There is very little in that VI that is correct. Your comparisons are still not correct and you need a false case for each Case Structure with the error wired through. Wht you are merging the Boolean to pass to the spectral function is also a mystery to me.

[shinjita]

okay, i will try doing it again

[shinjita]

Hello

            Is there a way to store the data in the file and then use that file in the fft analysis program(the custom made fft program) instead of the file that is there and create it in such a way that the program starts running after some time of data recording?

Regards

Shinjita

[Andy.G]

Hey Shinjita,

To help you along a little bit I have written a simple VI that should get you on your feet with your DAQ problem. It takes the information of one cycle acquired by your DAQ and using a simple piece of logic, will ensure the data between two specified points is collated and recorded using the “write to measurement file” express VI. This is achieved using a for loop and case structure, when the values is between the specified points it will write the data to file, however if it is not I have written a little bit of code to ensure that the data recorded is set to a constant of either the maximum or minimum data value. This of course is optional, just makes the output graph look nice. Attached I have a print screen of the code I have made, and if you are using LV 2009 I can also give you a snippet which you can copy directly from your desktop into LV itself.

Also I would highly recommend that you go through some of the tutorials before attempting to write any code in the future. 

http://www.ni.com/gettingstarted/labviewbasics/

[shinjita]

Hello

       Thank you very much.

Regards

Shinjita