Reading Data from Arduino

Jessun

I am having a weird problem with Processing Programming Language.

1. I can read and store the data as a text file from a Arduino board with the program shown below. It works fine.

2. I wanted to read data from multiple boards and record in one text file. I saved the file with a different name and made some chnages. It stopped working. I compared line by line with the unchanged file and deleted the chages, still it did not work.

3. I was surprised to see that even an insignificant change makes the program unworkable. Even if I comment-out the line, the program does not work any more. It is explained below.

To_Txt_No_Dgtl.pde

/*

+++  WARNING: ANY FILE WITH TODAY'S DATE WILL BE OVERRITTEN +++

       * Receive Multiple Fields Binary To File_P
       *
       * portIndex must be set to the port connected to the Arduino
       * based on ReceiveMultipleFieldsBinary, this version saves data to file
       * Press any key to stop logging and save file
       */

import processing.serial.*;

PrintWriter output;
String fileNm;
String prtNm;
Serial myPrt, myPrt1;                                // Create object from Serial class
short prtIndx = 2;                          // select the com port, 0 is the first port
char HEADER = 'H';
int TtlPrt = 0;
int strtng, dy = 0;
int val;
String y, m, d;
String hr;
String mn;
String s;
String t;


void setup()
{
  size(200, 200);
  dy = day();

  TtlPrt = Serial.list().length;                    // Counts how many com ports are present

  if (TtlPrt <=2)                                   // i.e. Arduino is connected or not
  {
    println("Only " + TtlPrt + " COM ports are present.");
    println("May be, Arduino is not connected.");
  }
  else
  {
                                                              // Open whatever serial port is connected to Arduino.
    String prtNm = Serial.list()[prtIndx];
    println(Serial.list());
    println(" Connecting to -> " + Serial.list()[prtIndx]);
    myPrt1 = new Serial(this, prtNm, 9600);
  }
}

void draw()
{
  if (TtlPrt <=2) 
    exit();
  else
  {                                         // After running, for the first time a file is created
    if (strtng == 0 || dy != day())
    {
      y = str(year());
      m = str(month());
      d = str(day());
      if (month() < 10)
        m = "0" + m;
      if (day() < 10)
        d = "0" + d;

      if (dy != day())        // When continuosly running, if the date changes the existing file is closed and a new file is created
      {
        output.flush();                       // Writes the remaining data to the file
        output.close();                       // Closes the file
      }
      fileNm = (y + m + d);
      output = createWriter(fileNm + ".txt");
      output.println("  , " + "  , " + "   , " + "Room,   " + " Roof,  " + "S.Wall, " + "S.Wall, " + "  Roof, " + "E.Wall  ");
      output.println("Hr, " + "Mn, " + "Sec, " + "Centre, " + " under, " + "inside, " + "otside, " + "  top,  " + "outside " + "\n");
      strtng = 1;
      dy = day();
    }

    hr = str(hour());
    mn = str(minute());
    s = str(second());
    if (hour() < 10)
      hr = "0" + hr;
    if (minute() < 10)
      mn = "0" + mn;
    if (second() < 10)
    s = "0" + s;

    if ( myPrt1.available() >= 15)                      // wait for the entire message to arrive
    {
      if( myPrt1.read() == HEADER)       // is this the header
      {
            // header found
        println(hr + "  " + mn + "  " + s + "     ");
        output.print(hr + ", " + mn + ",  " + s + ", ");

// ------------ print the six analog port values ---------

        for(int i=0; i < 6; i ++)
        {
          val = 0;
          val = readArduinoInt1();
          println("analog port " + i + "= " + val);
        if (val <= 9)
          output.print("     " + val + ", ");
        if (val > 9 && val < 100)
          output.print("    " + val + ", ");
        if (val > 99 && val < 1000)
          output.print("   " + val + ", ");
        if (val > 999 && val < 10000)
          output.print("  " + val + ", ");
        if (val > 9999 && val < 100000)
          output.print(" " + val + ", ");
        }
        println("----");
        output.println("\n");
      }
    }
    k = k+1;
    if (k > 10)
    {
      k=0;
      output.flush();                     // Writes the remaining data to the file
    }
  }
}
void keyPressed()
{
  output.flush();                       // Writes the remaining data to the file
  output.close();                       // Finishes the file
  exit();                               // Stops the program
}

// ---------- Function for value reading from COM2 -------------

                                        // return the integer value from bytes received on the serial port
                                        // (in low,high order)
int readArduinoInt1()
{
  int val;                              // Data received from the serial port
  val = myPrt1.read();                  // read the least significant byte
  val =  myPrt1.read() * 256 + val;           // add the most significant byte
  return val;
}
                                        // (in low,high order)

===========================================

1. The "if-then" loop from line 103 to 132 works fine.

2. But, if I add an "else" loop the working loop stops working as shown below:

++++++++++++++++++++++++++++++++++++++++

if ( myPrt1.available() >= 15)
{
  Working codes
}
else
{
  println("Port is not available");
}

++++++++++++++++++++++++++++++++++++++++

Note: The curly brackets are not necessary, as it is only one line after "else".

The idea of this program was adopted from Arduino Cookbook by Michael Margolis.