Arduino Code

int numberOfPotis = 2;
int numberOfButtons = 5;
int potiValues[2] = {0, 0};
int highLowValues[2][2] = {{1023, 0}, {1023, 0}};

void setup() {
  Serial.begin(1000000);

  for (int i = 0; i < numberOfPotis; i++) {
    analogWrite(i + 2, 255);
    setPhysicalFaderValueToFull (i);
    highLowValues[i][1] = analogRead(i);
    setPhysicalFaderValueToNull (i);
    highLowValues[i][0] = analogRead(i);
  }
  Serial.println("S;E");
}

void loop() {
  if (Serial.available() > 0 && char(Serial.read()) == 'S') {
    readMsg();
  }
  int newValue;
  for (int i = 0; i < numberOfPotis; i++)
  {
    newValue = readPoti(i);
    if (newValue != potiValues[i]) {
      potiValues[i] = newValue;
      String line;
      line =  "S;0;1;" + String(1) + ";" + String(i) + ";" + String(potiValues[i]) + ";" +  String(newValue) + ";E"; //System: S;commandType(1=getValue);valueType;sensorID;value;debugInfo;E
      Serial.println(line);
    }
  }
}

void setPhysicalFaderValueToNull (int faderID) {
  int upPin = 22 + (2 * faderID);
  int downPin = upPin + 1;
  digitalWrite(downPin, HIGH);
  digitalWrite(upPin, LOW);
  delay(500);
  digitalWrite(downPin, LOW);
}

void setPhysicalFaderValueToFull (int faderID) {
  int upPin = 22 + (2 * faderID);
  int downPin = upPin + 1;
  digitalWrite(upPin, HIGH);
  digitalWrite(downPin, LOW);
  delay(500);
  digitalWrite(upPin, LOW);
}

void setMotorPoti(int faderID, int value) {
  int upPin = 22 + (faderID * 2);
  int downPin = upPin + 1;
  int speed1 = 140;
  int speed2 = 110;
  int range = 5;

  while (readPoti(faderID) != value) {
    analogWrite(faderID + 2, speed1);
    while (getPositiveInt(value - readPoti(faderID))>range) {
      int potiValue = readPoti(faderID);
      if (potiValue < value) {
        digitalWrite(upPin, HIGH);
        digitalWrite(downPin, LOW);
      }

      if (potiValue > value) {
        digitalWrite(upPin, LOW);
        digitalWrite(downPin, HIGH);
      }
      Serial.println("High");
    }

    analogWrite(faderID + 2, 255);
    while (readPoti(faderID) != value) {
      int potiValue = readPoti(faderID);
      analogWrite(faderID + 2, map(getPositiveInt(value - potiValue), 0, 100, speed2, 255) * 1);
      if (potiValue < value) {
        digitalWrite(upPin, HIGH);
        digitalWrite(downPin, LOW);
      }

      if (potiValue > value) {
        digitalWrite(upPin, LOW);
        digitalWrite(downPin, HIGH);
      }
      Serial.print("LOW: ");
      Serial.println(potiValue);
    }
    digitalWrite(upPin, LOW);
    digitalWrite(downPin, LOW);
    if (readPoti(faderID) != value) delay(100);
  }
  potiValues[faderID] = value;
}

void readMsg() {
  boolean msgComplete = false;
  int msgValues[2] = {0, 0};
  int activeSlot = -1;
  while (Serial.available() > 0) {
    char nextChar = char(Serial.read());
    switch (nextChar) {
      case 'E':
        msgComplete = true;
        break;
      case ';':
        activeSlot++;
        break;
      default:
        msgValues[activeSlot] = (msgValues[activeSlot] * 10) + (nextChar - '0');
        break;
    }
    if (nextChar == 'E') {
      break;
    }
  }
  if (msgValues[0] < numberOfPotis && msgValues[1] <= 100) {
    //    while (readPoti(msgValues[0]) != msgValues[1]) {
    setMotorPoti(msgValues[0], msgValues[1]);
    //      delay(10);
    //    }
  }
}

int readPoti(int pin) {
  int iterations = 30;
  int gesammt = 0;
  for (int i = 0; i < iterations; i++) {
    gesammt += analogRead(pin);
  }
  return map(gesammt / iterations, highLowValues[pin][1], highLowValues[pin][0] - 1, 100, 0);
}

int getPositiveInt (int i) {
  if (i < 0) i = i * -1;
  return i;
}