Hallo Markus,
Du hast natürlich Recht. Die Auskommentierungen waren durch die Versuche gekommen. Hier der org. Arduinocode.
Code:
  const int RMotor1  = 2;    // H-bridge leg 3       Input 1        14,4V Motor
  const int RMotor2  = 4;    // H-bridge leg 2       Input 2  
  const int RSpeed = 3;      // H-bridge leg 7       Enable A (PWM) 
  const int LMotor1 = 7;     // H-bridge leg 13      Input 3        12V Motor
  const int LMotor2 = 8;     // H-bridge leg 14      Input 4  
  const int LSpeed = 6;      // H-bridge leg 10      Enable B (PWM) 
  
  const int ledBlue = 12;    // BlueLED  left Motor
  const int ledRed = 13;     // RedLED  right Motor 
  
  int PinOdoR = 0;           // right Pin for IR-Sensor
  int PinOdoL = 1;           // left Pin for IR-Sensor
  // int mSpeedR = 0;        // is not needed in this Kontex ?
  // int mSpeedL = 0;
  // int mDirR = 0;
  // int mDirL = 0;

  // int LedPwmR = 0;
  // int LedPwmB = 0;
  
  int readAnalog(int port);  // Why are these functions initialized here?
  int readOdoR ();
  int readOdoL ();
    
//-------------------------- Left Motor -----------------------------------------------
  void motorR (int InputPin2, int InputPin4, int pwm3){
      digitalWrite(RMotor1, InputPin2);   
      digitalWrite(RMotor2, InputPin4);
      analogWrite(RSpeed, pwm3);
  }       
//-------------------------- Right Motor ----------------------------------------------
  void motorL (int InputPin7, int InputPin8, int pwm6){
      digitalWrite(LMotor1, InputPin7); 
      digitalWrite(LMotor2, InputPin8);
      analogWrite(LSpeed, pwm6);
  }
 //-------------------------- Stop Motor ----------------------------------------------
  void motorStop (){
      motorL(LOW, LOW, 0); 
      motorR(LOW, LOW, 0); 
  } 
//-------------------------- Setup ----------------------------------------------------
 void setup() {
    
    // set all the other pins you're using as outputs:
    pinMode(RMotor1, OUTPUT); 
    pinMode(RMotor2, OUTPUT); 
    pinMode(RSpeed, OUTPUT);
    pinMode(LMotor1, OUTPUT); 
    pinMode(LMotor2, OUTPUT); 
    pinMode(LSpeed, OUTPUT);
   
    pinMode(ledBlue, OUTPUT);
    pinMode(ledRed, OUTPUT);
        
    Serial.begin(115200);
    // motorStop();        // would be necessary at all?
    Serial.println("***********************");
    Serial.println("* Encoder-Test        *");
    Serial.print("* ");Serial.print(__DATE__);Serial.print(" ");Serial.print(__TIME__);Serial.println("*");
    Serial.println("***********************");

    blink(ledRed, 3, 1000);
  }
//------------------------------------------------------------------------------
  void loop() {
        int RSpeed = 170;
        int LSpeed = 150;
        motorR(HIGH,LOW,RSpeed);         
        motorL(HIGH,LOW,LSpeed);
        delay(1000);
        
        Serial.println(" Encoder Rechts/Links ");
        for (int i = 0; i <= 100; i++)
        {
          int valR = readOdoR();
          int valL = readOdoL();
          Serial.print(" ");Serial.print(valR,DEC);Serial.print("  ;");Serial.print(valL,DEC);Serial.println(" ");
          delay (15);                                      // hängt dieser Wert von der Drehzahl des Encoders ab?
           if (valR > 400)  { digitalWrite(ledRed,HIGH); }
              else { digitalWrite(ledRed,LOW); }
           if (valL > 400)  { digitalWrite(ledBlue,HIGH); }
              else { digitalWrite(ledBlue,LOW); }
        }
        Serial.println(" ");
	motorStop();         
       	Serial.println("***********************");
	delay (5000);
}
//------------------------------------------------------------------------------
int readOdoR (){
	return readAnalog (PinOdoR);
}
//------------------------------------------------------------------------------
int readOdoL (){
	return readAnalog (PinOdoL);
}
//------------------------------------------------------------------------------
int readAnalog(int port){
	int val = 0;
	for (int i = 0; i <= 3; i++)
	  { val = val + analogRead(port); }
	    val = val/3;
	return val;
}
//--------------------------  blinks an LED ------------------------------------
  void blink(int whatPin, int howManyTimes, int milliSecs) {
    int i = 0;
    for ( i = 0; i < howManyTimes; i++) {
      digitalWrite(whatPin, HIGH);
      delay(milliSecs/2);
      digitalWrite(whatPin, LOW);
      delay(milliSecs/2);
    }
}
//------------------------- Programm Ende ---------------------------------------
Ich hoffe ich habe Deinen Tipp richtig verstanden.

Code:
/***************************************************************************
 *
 * File Name:   Encoder-Test
 * Project  :   Scheibenbot Kucky 1
 *
 * Description: Freie Bewegungen im unbekannten Raum
 *
 * Ver.     Date         Author               Comments
 * -------  ----------   -----------------    ------------------------------
 * 0.1      12.08.2010   W. Kuckelsberg       initial build
 *
 *  Co-Author and helpfull Hand: Stephan Scholz
 *  Hardware: Arduino Duemillenova
 *  H-bridge: L298H
 *  Self test for Encoderdisc
 *  Informations:
 *  right planetmotor rotates until ???
 *  left  planetmotor rotates until ???
 */

#include <WProgram.h>

  const int RMotor1  = 2;    // H-bridge leg 3       Input 1        14,4V Motor
  const int RMotor2  = 4;    // H-bridge leg 2       Input 2
  const int RSpeed = 3;      // H-bridge leg 7       Enable A (PWM)
  const int LMotor1 = 7;     // H-bridge leg 13      Input 3        12V Motor
  const int LMotor2 = 8;     // H-bridge leg 14      Input 4
  const int LSpeed = 6;      // H-bridge leg 10      Enable B (PWM)

  const int ledBlue = 12;    // BlueLED  left Motor
  const int ledRed = 13;     // RedLED  right Motor

  int PinOdoR = 1;           // right Pin for IR-Sensor
  int PinOdoL = 0;           // left Pin for IR-Sensor
  // int RSpeed = 120;        // is not needed in this Kontex
  // int LSpeed = 120;
  // int mDirR = 0;
  // int mDirL = 0;

  // int LedPwmR = 0;
  // int LedPwmB = 0;

  int readAnalog(int port);  // Why are these functions initialized here?
  int readOdoR();
  int readOdoL();
  void blink(int whatPin, int howManyTimes, int milliSecs);
  //void motorR (int InputPin2, int InputPin4, int pwm3);
  //void motorL (int InputPin7, int InputPin8, int pwm6);
  void motorL ();
  void motorR ();
  void motorStop();

  // -------------------------- Left Motor -----------------------------------------------
  void motorR (int InputPin2, int InputPin4, int pwm3){
      digitalWrite(RMotor1, InputPin2);
      digitalWrite(RMotor2, InputPin4);
      analogWrite(RSpeed, pwm3);
  }
//-------------------------- Right Motor ----------------------------------------------
  void motorL (int InputPin7, int InputPin8, int pwm6){
      digitalWrite(LMotor1, InputPin7);
      digitalWrite(LMotor2, InputPin8);
      analogWrite(LSpeed, pwm6);
  }
  //-------------------------- Setup ----------------------------------------------------
   void setup() {
      void motorStop();

      pinMode(RMotor1, OUTPUT);
      pinMode(RMotor2, OUTPUT);
      pinMode(RSpeed, OUTPUT);
      pinMode(LMotor1, OUTPUT);
      pinMode(LMotor2, OUTPUT);
      pinMode(LSpeed, OUTPUT);

      pinMode(ledBlue, OUTPUT);
      pinMode(ledRed, OUTPUT);

      Serial.begin(115200);
      // motorStop();        // would be necessary at all?
      Serial.println("***********************");
      Serial.println("* Encoder-Test        *");
      Serial.print("* ");Serial.print(__DATE__);Serial.print(" ");Serial.print(__TIME__);Serial.println("*");
      Serial.println("***********************");

    blink(ledBlue, 3, 1000);
    }
  //------------------------------------------------------------------------------
   void loop() {

		int RSpeed = 120;
          int LSpeed = 120;
          motorR(HIGH,LOW,RSpeed);
          motorL(HIGH,LOW,LSpeed);
          delay(2000);

          Serial.println(" Encoder Rechts/Links ");
          for (int i = 0; i <= 52; i++)
          {
            int valR = readOdoR();
            int valL = readOdoL();
            Serial.print(" ");Serial.print(valR,DEC);Serial.print("  ;");Serial.print(valL,DEC);Serial.println(" ");
            delay (10);                                      // hängt dieser Wert von der Drehzahl des Encoders ab?
             if (valR > 400)  { digitalWrite(ledRed,HIGH); }
                else { digitalWrite(ledRed,LOW); }
             if (valL > 400)  { digitalWrite(ledBlue,HIGH); }
                else { digitalWrite(ledBlue,LOW); }
          }
          Serial.println(" ");
  	// motorStop();
         	Serial.println("***********************");
  	delay (5000);
  }


 //-------------------------- Stop Motor ----------------------------------------------
  void motorStop (){
      motorL(LOW, LOW, 0);
      motorR(LOW, LOW, 0);
  }
//------------------------------------------------------------------------------
int readOdoR(){
	return readAnalog (PinOdoR);
}
//------------------------------------------------------------------------------
int readOdoL(){
	return readAnalog (PinOdoL);
}
//------------------------------------------------------------------------------
int readAnalog(int port){
	int val = 0;
	for (int i = 0; i <= 3; i++)
	  { val = val + analogRead(port); }
	    val = val/3;
	return val;
}
//--------------------------  blinks an LED ------------------------------------
  void blink(int whatPin, int howManyTimes, int milliSecs) {
    int i = 0;
    for ( i = 0; i < howManyTimes; i++) {
      digitalWrite(whatPin, HIGH);
      delay(milliSecs/2);
      digitalWrite(whatPin, LOW);
      delay(milliSecs/2);
    }
}
//------------------------- Programm Ende ---------------------------------------

int main(void) {

  /* Must call init for arduino to work properly */
  init();
  setup();

  for (;;) {
	  loop();
  } // end for
} // end main
Nun bekomme ich diese Meldung:
"D:\UserDaten\Users\Willi\Prog\Projekte\ProjEclips e\ArduinoCore\Release\libArduinoCore.a(Print.o).data+0x6): undefined reference to `__cxa_pure_virtual'
make: *** [Encoder.elf] Error 1"
(der traurige Smilie entstand zwar automatisch, passt aber irgendwie)

Die ArduinoCore ist im Verzeichniss "xxx/ArduionoCore/Release"
Die Dateien mit der Endung *.h sind im Verzeichniss "xxx/ArduionoCore"
Ist das richtig? Wurde automatisch beim erstellen der static Library so hinterlegt. Oder müssen die alle in einem Verzeichniss sein. Um das Problem zu umgehen, habe ich beide Verzeichnisse bei den Projekteinstellungen genannt.
Wäre es für Dich sehr viel Aufwand, meine Code in Eclipse so umzuschreiben, dass ich hier schon mal keinen Fehler habe. =D>
Ich weiss das ist ziemlich unverschämt, wäre Dir aber wirklich sehr dankbar.
Gruß
Willi