Please take a look at my serial handling in my app

janeik

Please take a look at my serial handling in my app

in Integration and Hardware • 10 months ago

hello.

Im most bad in serial communication. Sometimes I can start Processing app without error and sometimes following error shows up :

error, disabling serialEvent() for //./COM4
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at processing.serial.Serial.serialEvent(Unknown Source)
at gnu.io.RXTXPort.sendEvent(RXTXPort.java:732)
at gnu.io.RXTXPort.eventLoop(Native Method)
at gnu.io.RXTXPort$MonitorThread.run(RXTXPort.java:1575)
Caused by: java.lang.ArrayIndexOutOfBoundsException: 2
at trial2.serialEvent(trial2.java:81)
... 8 more

Appreciate any comments regarding serial. Thank You in advance.

regards

---------

Snippet of Arduino output app, x,y,z are double variabletypes:

//Output the caculations
Serial.print(x);
Serial.print(",");
Serial.print(y);
Serial.print(",");
Serial.println(z);
Serial.flush();

Snippet of Processing app included in serial communication:

Setup void func:

println(Serial.list());
frameRate(50);

// Open whatever port is the one you're using.
myPort = new Serial(this, Serial.list()[1], 115200);
myPort.bufferUntil(lf);

Serial event func:

inString = p.readString();
lengde=inString.length();
inString=inString.substring(0, lengde-1);
float[] vals = float(splitTokens(inString,","));
xin=vals[0];
yin=vals[1];
zin=vals[2];
// plot accel combined with gyroscope combined/not combinded with complementary filtering
plott();
teller=teller+1;
if (teller==(int)(displayWidth)-64)
                                      {
                                        teller=192;
                                        fill(202);
                                        rect(193.0,0.0,(float)displayWidth-64.0,(float)line2-1.0);
                                        noFill();
                                       }
}

Full listing of Arduino app:

#include <SoftwareSerial.h>
//////////////////////////////////////////////////////////////////
//©2011 bildr
//Released under the MIT License - Please reuse change and share
//Simple code for the ADXL335, prints calculated orientation via serial
//////////////////////////////////////////////////////////////////
String accel;
//Analog read pins
const int xPin = 0;
const int yPin = 1;
const int zPin = 2;
//The minimum and maximum values that came from
//the accelerometer while standing still
//You very well may need to change these
int minVal = 265;
// int maxVal = 402;
int maxVal = 402;
//to hold the caculated values
double x;
double y;
double z;
void setup(){
Serial.begin(115200);
}
void loop(){
//read the analog values from the accelerometer
int xRead = analogRead(xPin);
int yRead = analogRead(yPin);
int zRead = analogRead(zPin);
//convert read values to degrees -90 to 90 - Needed for atan2
int xAng = map(xRead, minVal, maxVal, -90, 90);
int yAng = map(yRead, minVal, maxVal, -90, 90);
int zAng = map(zRead, minVal, maxVal, -90, 90);
//Caculate 360deg values like so: atan2(-yAng, -zAng)
//atan2 outputs the value of -π to π (radians)
//We are then converting the radians to degrees
x = RAD_TO_DEG * (atan2(-yAng, -zAng) + PI);
y = RAD_TO_DEG * (atan2(-xAng, -zAng) + PI);
z = RAD_TO_DEG * (atan2(-yAng, -xAng) + PI);
//Output the caculations
Serial.print(x);
Serial.print(",");
Serial.print(y);
Serial.print(",");
Serial.println(z);
Serial.flush();
// delay(10);//just here to slow down the serial output - Easier to read
}

Full listing of the Processing app:

import processing.serial.*;

Serial myPort;    // The serial port
PFont myFont;     // The display font
String inString; // Input string from serial port
int lf = 10;      // ASCII linefeed
int environx,environy,environz;
int rotx=90,roty=0,rotz=0; //holds rotation parameters
int linezero; // holds (1/6)- 36 of displayheight
int line1,line2,line3,line4,line5,line6;
float line90,line270,xin,yin,zin;
int lengde=0,teller=0;
int plotstart=0;
boolean bflag1=false,bflag2=false,bflag3=false,bflag4=false,bflag5=false,bflag6=false,bflag7=false;
void setup() {

environx=displayWidth;
environy=displayHeight-36;
linezero=environy/6;
line1=linezero;line2=linezero*2;line3=linezero*3;line4=linezero*4;line5=linezero*5;line6=linezero*6;line90=linezero*1.5;line270=linezero*0.5;
size(environx-32, environy);
background(202);
drawlines();
makebutton(192,line2+24,66,33,1,"ACCEL-X",8,255,255,255,0,0,180);
makebutton(288,line2+24,66,33,1,"ACCEL-Y",8,255,255,255,100,50,0);
makebutton(384,line2+24,66,33,1,"ACCEL-Z",8,255,255,255,250,0,250);
makebutton(512,line2+24,66,33,1,"COMPLIM",8,255,255,255,0,180,0);
makebutton(608,line2+24,66,33,1,"P-I-D",8,255,255,255,180,0,0);

makebutton(192,line4-56,66,33,1,"GYRO-X",8,255,255,255,240,140,12);
makebutton(288,line4-56,66,33,1,"GYRO-Y",8,255,255,255,240,140,12);
makebutton(384,line4-56,66,33,1,"GYRO-Z",8,255,255,255,240,140,12);

// List all the available serial ports:
println(Serial.list());
frameRate(50);

// Open whatever port is the one you're using.
myPort = new Serial(this, Serial.list()[1], 115200);
myPort.bufferUntil(lf);
}

void draw()
{
// draw LED indicators
indi();
}

void serialEvent(Serial p)
{
inString = p.readString();
lengde=inString.length();
inString=inString.substring(0, lengde-1);
float[] vals = float(splitTokens(inString,","));
xin=vals[0];
yin=vals[1];
zin=vals[2];
// plot accel combined with gyroscope combined/not combinded with complementary filtering
plott();
teller=teller+1;
if (teller==(int)(displayWidth)-64)
                                      {
                                        teller=192;
                                        fill(202);
                                        rect(193.0,0.0,(float)displayWidth-64.0,(float)line2-1.0);
                                        noFill();
                                       }
}
void drawlines()
{
stroke(127);
line(192,line1,180,line1);
line(180,line2,environx-64,line2);
line(180,line90,192,line90);
line(180,line270,192,line270);

line(192,line4,environx-64,line4);
line(192,line5,environx-64,line5);
line(192,line6,environx-64,line6);
fill(0,0,0);
text("360", 150,10 );
text("270", 150,line270);
text("180",150,line1);
text("90", 150,line90);
text("0", 150, line2);

text("ROLL",192,line2+99);
text("NICK",288,line2+99);

text("ROLL",192,line4-99);
text("NICK",288,line4-99);
text("YAW",384,line4-99);

// text("180",150,line3);
// text("0", 150, line4);
text("360", 150,line4);
text("180",150,line5);
text("0", 150, line6);

line(192,0,192,line2);

// draw vertical lines
// line(192,environy/3,192,environy/3-180);

}
void makebutton(int bposx,int bposy,int bwidth,int bheight,int bscale,String tekst,int tekstsize, int trcolor,int tgcolor,int tbcolor,int brcolor,int bgcolor,int bbcolor)
{
fill(brcolor,bgcolor,bbcolor);
rect(bposx,bposy,bwidth*bscale,bheight*bscale);
noFill();
fill(trcolor,tgcolor,tbcolor);
// textSize(tekstsize);
text(tekst, bposx+((bwidth-textWidth(tekst))/2), bposy+(bheight/2)+tekstsize/2);
noFill();
}
void mouseClicked()
{   // Button ACCEL X
    if (mouseX > 192 && mouseX < 258 && mouseY > (line2+24) && mouseY < (line2+57))
        {
          bflag1=!bflag1;
        }
    // Button ACCEL Y
    if (mouseX > 288 && mouseX < 354 && mouseY > (line2+24) && mouseY < (line2+57))
        {
          bflag2=!bflag2;
        }
    // Button ACCEL Z
    if (mouseX > 384 && mouseX < 450 && mouseY > (line2+24) && mouseY < (line2+57))
        {
          bflag3=!bflag3;
        }
    // Button COMPLIMENTARY FILTER
    if (mouseX > 512 && mouseX < 578 && mouseY > (line2+24) && mouseY < (line2+57))
        {
          bflag4=!bflag4;
        }
}
// draw LED indicators
void indi()
{
if (bflag1==true)
                    {
                      fill(0,255,0);
                      ellipse(225,line2+66,10, 10);
                      noFill();
                    }
if(bflag1==false)
                    {
                      fill(255,0,0);
                      ellipse(225,line2+66,10, 10);
                      noFill();
                    }


if (bflag2==true)
                    {
                      fill(0,255,0);
                      ellipse(321,line2+66,10, 10);
                      noFill();
                    }
if(bflag2==false)
                    {
                      fill(255,0,0);
                      ellipse(321,line2+66,10, 10);
                      noFill();
                    }


if (bflag3==true)
                    {
                      fill(0,255,0);
                      ellipse(417,line2+66,10, 10);
                      noFill();
                    }
if(bflag3==false)
                    {
                      fill(255,0,0);
                      ellipse(417,line2+66,10, 10);
                      noFill();
                    }


if (bflag4==true)
                    {
                      fill(0,255,0);
                      ellipse(545,line2+66,10, 10);
                      noFill();
                    }
if(bflag4==false)
                    {
                      fill(255,0,0);
                      ellipse(545,line2+66,10, 10);
                      noFill();
                    }

}
void plott()
{
// plot accell x,y,z
if(bflag1==true)
{
stroke(0.0,0.0,180.0);
point(plotstart+teller,(float)line2-xin);
noStroke();

if (bflag4==true)
{
// run complimentary filter
// plot point in green color
}
}

if(bflag2==true)
{
stroke(10.0,50.0,0.0);
point(plotstart+teller,(float)line2-yin);
noStroke();
if (bflag4==true)
{
// run complimentary filter
// plot point in green color
}
}

if(bflag3==true)
{
stroke(250.0,0.0,250.0);
point(plotstart+teller,(float)line2-zin);
noStroke();

if (bflag4==true)
{
// run complimentary filter
// plot point in green color
}
}
}
/*
// complimentary filter
float filterAngle;
float dt=0.02;
float comp_filter(float newAngle, float newRate) {
float filterTerm0;
float filterTerm1;
float filterTerm2;
float timeConstant;
timeConstant=0.5; // default 1.0
filterTerm0 = (newAngle - filterAngle) * timeConstant * timeConstant;
filterTerm2 += filterTerm0 * dt;
filterTerm1 = filterTerm2 + ((newAngle - filterAngle) * 2 * timeConstant) + newRate;
filterAngle = (filterTerm1 * dt) + filterAngle;
return previousAngle; // This is actually the current angle, but is stored for the next iteration
}

*/

Replies(3)

PhiLho

Re: Please take a look at my serial handling in my app

10 months ago

" java.lang.ArrayIndexOutOfBoundsException: 2"
See Why do I get an ArrayIndexOutOfBoundsException? for details.
In your case, it seems that vals[] has only two entries instead of the expected three.

Note: Zoho is badly behaved today with my link, see the Technical FAQ page and go to the article above.

janeik

Re: Please take a look at my serial handling in my app

10 months ago

thanks PhiLho.

I have just tested the code finding theres something about the array investigating the below code.

Was just about to update my forumthread.

Well, if only 2 arraymembers are made, I think that points to either

a) defining of array

b) wrong parameter/casting in splittoken

cause theres no error until those instructions.

Ill try to find more details about the a and b and read the link You attached.

Do You think the instructions regarding reading are sufficient to avoid reading in middle of inncomming informations?

thank You

// Example by Tom Igoe
float xin,yin,zin;
import processing.serial.*;
int lengde;
int lf = 10; // Linefeed in ASCII
String myString = null;
Serial myPort; // The serial port
void setup() {
// List all the available serial ports
println(Serial.list());
// Open the port you are using at the rate you want:
myPort = new Serial(this, Serial.list()[1], 115200);
myPort.clear();
// Throw out the first reading, in case we started reading
// in the middle of a string from the sender.

myString = myPort.readStringUntil(lf);
myString = null;

}
void draw()
{
}
void serialEvent(Serial p)
{
myString = myPort.readStringUntil(lf);
    if (myString != null)
    {

lengde=myString.length();
myString=myString.substring(0, lengde-1);

// removing the below line, transmission now and then stops from arduino, without error reporting in Processing
// float[] vals = float(splitTokens(myString,", null"));

// removing the below, transmission now and then stops from arduino, without error reporting in Processing. (Arduino app stops transmitting)
// not removing the below,error is now and then reported from Processing (Processing app. stops)
// xin=vals[0];
// yin=vals[1];
// zin=vals[2];
}
}

janeik

Re: Please take a look at my serial handling in my app

10 months ago

Ive tested, by printing how many tokens received after executing splitTokens.

Sometimes it shows only 2 (instead of expected 3), after startup of processing application.

I think Its about not reading at proper "key" of incomming stream (?)

I need a check that I read right after a linefeed after aproper check of incomming stream

The only way I can guess would do that, o s testing if the expected incomming data has valid information

or setup a kind of handshaking (dont send anything from Arduino before Arduino receives a "ready to receive" byte/char/string from processing app.

How does that sound?

regards

Top Reply