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Bahattin Gok

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May 12, 2019, 6:39:44 AM5/12/19
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Hi again, I am new starter to mıt app, so  that could be I didnt understand some point that you showed.My last post is closed. I changed code and some thing and I had like that chart.( By the way I changed signal source, firstly I try AD8232 and now I use my ECG circuit. Its chart is in post. And programm has like this chart. 




#include <SoftwareSerial.h>
int in = A0;
SoftwareSerial bt_connection(2, 3); // RX, TX
void setup() {
  // initialize the serial communication:
  
  Serial.begin(9600);
  bt_connection.begin(9600);
  pinMode(in, INPUT);

}

void loop() {
    byte val =map(analogRead(in), 0,1024.0, 0, 255);
    bt_connection.write(val);
    delay(30);  
}



Normally to be like that


mıy3.png
But it my chart on app seems like that
mıy4.jpg

mıy.png


mıy2.png

Thank you all.

SteveJG

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May 12, 2019, 7:49:19 AM5/12/19
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T following Forum post (making a seismograph) plots a similar data stream (look for the Accelerometer_copy_copy.aia file  on ^/25/14).  It shows a technique to plot using the Canvas that is scaled.  You need to do something similar with your ECG data.  You will have to experiment.  Load the aia and see how this was done with seismic data and you should be able to do something similar.

Or you might want to use a graphing extension.



Regards,
Steve

Bahattin Gok

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May 12, 2019, 12:43:37 PM5/12/19
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Hi, I searched your advice file, I found it but there is wrong. Its file code blocks empty.

SteveJG

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May 13, 2019, 9:20:08 AM5/13/19
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Is this the link you found Bahattin  https://groups.google.com/forum/#!msg/mitappinventortest/xXOUXOxPLZQ/9U4RWID_VX8J;context-place=msg/mitappinventortest/IheCDlPnjdc/dU1uQQoeAgAJ  

The aia downloads properly here.  There are two Screens ... look at the Blocks on the   "graphingScreen" perhaps?  You might try again.

seismic.jpg.jpg





Bahattin Gok

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May 15, 2019, 9:28:35 AM5/15/19
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mıt.png

I am really sorry, I dont understand. If you have more examles about basic I chec them but, ı didnt  find canvas examples. By the way when I did like this code, on phone seems like that. '128' 

mıt2.png

SteveJG

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May 15, 2019, 10:19:32 AM5/15/19
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You might want to try harder Bahattin.  The Blocks required to create a scaled graph on a Canvas are shown.   What is shown to plot a scaled graph using the Canvas is complicated
 




If you want to plot your ECG to look like the example you posted in real time, you
 will have to create your blocks to look something similar in your app.  

seismicGraph.png



the reason your code looks the way it does is because it is NOT scaled.

SteveJG

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May 15, 2019, 12:21:54 PM5/15/19
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Here is a link to a Project discussed in the Forum that is similar to your Bluetooth ECG .   It uses a SCALED canvas .   It may be easier to understand than the complex graphing solution.

Regards,
Steve



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