Signal from Graph to FFT

I have a singal which has been stored to a binary file. I want to take it out and run a FFT on it and see all the peaks on one graph. Is this possible, I have tried and all i get out is garbage, but maybe I'm doing somethign wrong(most probably). Thanks for the help.
Intern NSWCCD Carderock.

needtolearnfast wrote:
I have a singal which has been stored to a binary file. I want to take it out and run a FFT on it and see all the peaks on one graph. Is this possible, I have tried and all i get out is garbage, but maybe I'm doing somethign wrong(most probably). Thanks for the help.
If the binary have not been generated by Labview, your problem might have to do with the reversed byte order used in LV (BIG ENDIAN vs. LITTLE ENDIAN). you can search for 'ENDIAN' in this forum to find tips.
Or use the following code snippet:
Attachments:
Unbenannt.PNG ‏5 KB

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Hello St Augustine,
Unfortunately, I cannot open these files that you have attached so I cannot tell you for certain where your problem lies. However, if you are using one of the FFT VIs from the Analzye>Waveform Measurements sub-palette, then you should be able to wire directly from the VI to a Waveform Graph. Make sure you are trying to wire to a Wavform Graph not a Waveform Chart. If you are using the FFT VIs on the Analyze>Signa Processing>Frequency Domain sub-palette, you should also be able to directly wire into a Waveform Graph, but please refer to the KnowledgeBase document linked below for more information about plotting complex numbers.
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Hi Lynn,
Thanks for your help and for sending the demo.
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progers - There is not a specific solution, as there is not a device driver for this device (assuming you are also using a pyrometer).
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Untitled.jpg ‏57 KB

Hi uday ,
Thank you for a fast response .
The VI in the above link shows how to extract a portion of graph with use of cursors. In my VI the user won't do anything . Everything should happen automatically.
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Untitled.jpg ‏57 KB

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Hello Lynn,
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Attachments:
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input receber.png ‏37 KB

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Solved!
Go to Solution.

Attached herewith is a print screen of what is showing on MAX
The CAN ports are on NI PXI-8461
Hopefully that clarrifies something.
Attachments:
Untitled.png ‏212 KB
Untitled.png ‏212 KB

How to read and display a signal from my PIC Microcontroller onto Labview?

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Attachments:
Getting Started with Labview.pdf ‏901 KB

Hi Ashwin,
It is a good idea to first be able to communicate with the microcontroller using some sort of serial communication software such as "HyperTerminal" or "Procomm", etc. Refer to MicroChip's recommendations on this.
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How to read and display a signal from my PIC Microcontroller onto Labview

Hi,
I am doing a project on a Pulse Oximeter and i am trying to read and display the signal from my PIC Microcontroller on Labview? How do i go about doing it? I am using the PIC16F877 and also making use of the USART?
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Also, i am using the RS232 serial interface to connect to the PC? The connector i am using is the DB9 Connector. Which template and VI can i use? Am i supposed to use the NI-DAQmx and VISA? Also, for my USART connection, i am using the MAX232 Driver which is applicable for my application as i am working with +5V. So far, i have been reading and trying out on Labview and the steps i have taken are:
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3) I was reading the Labview Manual, 'Getting Started with Labview' and i was following the steps under Page 55, Communicating with an Instrument. Am i on the right track?
4) How do i check and make sure that the port settings of the I/O Assistant and my PIC Micro Match
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Thank You
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Attachments:
Getting Started with Labview.pdf ‏901 KB

Hi Ashwin,
I am not familiar with the PIC Microcontrollers, but I am assuming you mean that you have the microcontroller sending out serial data that you want to read on another computer with LabVIEW. Please let me know if this is incorrect.
What type of data is coming out of the serial port? Is it ASCII, or binary? The reason I ask this is that the serial communication in LabVIEW is done through a protocol called VISA, which uses ASCII data to send and receive. You can later convert this data into whatever form you need, but this is what it is designed to read and write.
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You can also test communication in MAX by right clicking on the correct port and choosing Open VISA Session. Then choose the Basic I/O light blue tab, and then go to the Read tab. When you click execute, it should read in what is coming from the serial port. This will allow you to verify that the correct information is coming in before even trying to acquire the data in the LabVIEW environment.
In LabVIEW, the best resource to use the Basic Serial Write and Read example program that ships with LabVIEW. By examining the block diagram of this program, you will be able to see the basic programming flow of serial communication in LabVIEW.
I hope this information was helpful! Please let us know if there's anything else we can help with.
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Solved!
Go to Solution.

Lie detector systems (polygraphs) generally work by looking at the physiological responses to the own subjects baseline, and do this in real-time. You could use a file that represents the stored "baseline" for the subject, but the overall environment, circumstances, general state of the subject, etc. may not be similar enough to easily see subtle changes.
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Signal from Graph to FFT

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