Writing terminal COM data to graph using Visa

[paulyster]

Hello all.

This is my first post so try not to rip me to shreads for my lack of knowledge!

Well, my basic project idea is to have an arduino read a signal into labview serially using the XBee. So far I am able to get the instantaneous values of the graph in by numerical values, but I cant seem to actually be able to GRAPH it... i have an example VI that I 'borrowed' from another source... my ground knowledge of labview is so small. My goal is to actually graph an ECG signal quickly enough so that theres a full waveform that appears for the graph. I actually started learning the basics this february. If it can be done, can anyone give me any pointers? Anything will help!

[Jazlan]

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@paulyster wrote:

Hello all.

This is my first post so try not to rip me to shreads for my lack of knowledge!

Well, my basic project idea is to have an arduino read a signal into labview serially using the XBee. So far I am able to get the instantaneous values of the graph in by numerical values, but I cant seem to actually be able to GRAPH it... i have an example VI that I 'borrowed' from another source... my ground knowledge of labview is so small. My goal is to actually graph an ECG signal quickly enough so that theres a full waveform that appears for the graph. I actually started learning the basics this february. If it can be done, can anyone give me any pointers? Anything will help!

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Hi paulyster

Im also working on a similar project, however im interested in graphing an EMG signal using waveform chart/graps and writing the aquired data to labview lvm or tdms file for post processing. This is the VI i have used along with the initial results waveform graph (potentiometer reading).

The serial values are fluctuating, thats why the graph is not a straight line. Hope this helps.

Regards,

Jazlan

[Jazlan · Accepted solution]

On the arduino side, this is the code. The last 'delay' determines the sampling rate. I read that ECG/EMG signal sampling needs to adhere to Nyquist sampling theory. EMG maximum frequency is around 500Hz (low pass filter before ADC is set at 500Hz cut off), therefore the sampling has to be atleast twice the maximum frequency - atleast 1000Hz.

int potPin = 0;    // select the input pin for the potentiometer
int val = 0;       // variable to store the value coming from the sensor

void setup()
{
  Serial.begin(9600);    // opens serial port, sets data rate to 9600 bps
}

void loop() {
  val = analogRead(potPin); // read the value from the voltage divider
  Serial.println(val);
  delay(1);
}

[paulyster]

Thank you! It works!

[Jazlan]

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@paulyster wrote:

Thank you! It works!

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Glad to hear that paulyster!. Have you tried replacing the arduino-usb cable with the xbee tranceivers? If uve completed this part could you please upload ur VI and images of the aquired ECG waveform? I have yet to test whether this arrangment (xbee, VISA labview) works with biosignals such as ECG & EMG. There was also a write up on this ECG wireless transmission using xbee in elektor magazine january edition.

[Steve.J]

Hey guys - please post a summary of your projects and sample code (if possible!) on our Biomedical User Group (www.ni.com/biomedusers). We are seeing lots of interest in the Arduino module and any combination of Arduino and LabVIEW would get lots of attention!

Thanks,

Steve

[paulyster]

Tomorrow the VI and the arduino code should be posted... I do not have access to the ECG on a regular basis. If possible I will post pictures of the VI working.

[asr100]

hi paulyster,

 i m also working on xbee labview communication, i m using two xbees one at base n otherone at remote to which analog signal has been given and i m getting that signal at base pc in labview thr' base xbee.

now i wanna send ECG signal, will it possible to send ECG signal from remote xbee to base without any etxra controller.actually i am interested in using inbuilt controller of xbee also xbee rf data rate is 250kbps but how to set that using large baudrate .. any flow control is required for that like Xon - Xoff??

plz help

thanking you,

ajinkya

[paulyster]

I'm not sure how you'd do that without a microcontroller... it seems to me like the signal would have to be digitized before it can be sent.

[rita86]

Hi, 

I am using TI Board with MSP430 I am reading already dump program to display 1 to 10 numbers with little delay every 1sec it display values 1 to 10, now I am accessing it using serail port of MSP430 and getting result there its printing 1 to 10 values, I seen several VI saving the data and then dsiplaying in a chart, but in my case I am not able to do so.Plz help me where I am going wrong,Plz guide me to resolve the problem.