1

I am trying to plot a graph on processing but I'm having challenges going about it. The processing sketch below does work for plotting only one axis, and I'm trying to plot all three axis on the same sketch. Does anyone have an idea on how I could go about it. Below are the Arduino and Processing sketches.

Arduino

AcceleroMMA7361 ski;
int x;
int y;
int z;

void setup()
{
   Serial.begin(115200);
   ski.begin(13, 12,11,10, A0, A1, A2);
   ski.setARefVoltage(3.3);             
   ski.setSensitivity(HIGH);
   ski.calibrate();
}

void loop()
{
    x = ski.getXRaw();
    y = ski.getYRaw();
    z = ski.getZRaw();
   //Serial.print("\nx: ");
     Serial.println(x);
   //Serial.print("\ty: ");
   //Serial.print(y);
   //Serial.print("\tz: ");
   //Serial.print(z);
   delay(10);                                     //(make it readable)
}//End of Arduino Sketch

Processing

import processing.serial.*;

Serial myPort;        // The serial port
int xPos = 1;         // horizontal position of the graph

float fValue;
boolean newVal = false;

void setup () {
   size(800, 630);
   println(Serial.list());
   myPort = new Serial(this, Serial.list()[0], 115200);
   myPort.bufferUntil('\n');
   background(2);
   stroke(127, 34, 255);
}

void draw () {
    if (newVal) {
       line(xPos, height, xPos, height - fValue);
       if (++xPos >= width) {
         xPos = 0;
         background(2);
       }
       newVal = false;
    }
}

void serialEvent (Serial myPort) {
   String inString = myPort.readStringUntil('\n');
   if (inString != null) {
       inString = trim(inString);
       fValue = float(inString);
       fValue = map(fValue, 0, 1023, 0, height);
       newVal = true;
     }
}
1

I have edited your serialEvent() method a little bit, so it could handle the data from the Arduino, when split by a tab.

void serialEvent (Serial myPort) {
   String inString = myPort.readStringUntil('\n');

   if (inString != null) {
     values=split(inString,"\t");  //Splitting the output of the arduino into a String Array
     for(int i=0;i<values.length;i++){
       values[i]=trim(values[i]); //deleting the whitespaces as before
       float_values[i]=float(values[i]); //cast the string to a float as before
     }
       x = map(float_values[0], 0, 1023, 0, height); //map the value as before
       y = map(float_values[1], 0, 1023, 0, height);//map the value as before
       z = map(float_values[2], 0, 1023, 0, height);//map the value as before
       newVal = true;
     }
}

so your sending on the Arduino has to look like this:

void loop()
{
    x = ski.getXRaw();
    y = ski.getYRaw();
    z = ski.getZRaw();
    Serial.print("\n");
    Serial.print(x);
    Serial.print("\t");
    Serial.print(y);
    Serial.print("\t");
    Serial.print(z);
    delay(10);                                     //(make it readable)
}

You still have to make the drawing in the draw() method of processing, but I think that this is not the problem.

For the 3d draw you should have a look on the Processing reference or at this special topic, P3D by Daniel Shiffman.

I have not tested the code, but I think that it should work.

If you have questions, feel free to ask ;D

  • +1 - for taking the time to make the correction - however, you should test your code before posting it, as some people may just copy and paste the code without even thinking of testing it, which may have some unforeseen outcome. – Greenonline Mar 19 '16 at 1:35
  • 1
    There are two problems, why I have not tested my code: the first is, that I have no arduino avaible, because i have lend all of mine to the school for a group of robots acting together and the second reason is, that I have the final exams (i am from germany) in next tuesday – Sören Willrodt Mar 19 '16 at 20:43

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.