void nc(String st) {
  String xx, yy, zz;
  int ok = 1;
  st.toUpperCase();

  // makelangelo sends "N[0-9]+" for the line number
  // TODO Strip this out

  if (st.indexOf("G28") >= 0) {  // home - G28 [A] [B] [C] [L] [O] [R] [U] [V] [W] [X] [Y] [Z]
    //teleport(0, 0);              // home - should read which axises to home
    return;
  }
  if (st.indexOf("M0") >= 0) {  // stop M0 [P<ms>] [S<sec>] [string]
    // ignore for now - should delay for P ms and S secs
    return;
  }

  // TODO Read the feedrate from the F parameter --  F and A which are in motor steps per second.
  float x, y, z;
  int px, py, pz;
  px = st.indexOf('X');
  py = st.indexOf('Y');
  pz = st.indexOf('Z');
  if (px == -1 || py == -1) ok = 0;
  if (pz == -1) {
    pz = st.length();
  } else {
    zz = st.substring(pz + 1, st.length());
    z = zz.toFloat();
    //if (z > 0) pen_up();
    //if (z <= 0) pen_down();
  }

  xx = st.substring(px + 1);
  yy = st.substring(py + 1); // just change end to strlen it wll stop at the first non number

  //xx.trim(); // no need for this.. toFloat will trim
  //yy.trim();
  //if (ok) line(xx.toFloat(), yy.toFloat());

  if (ok) {
    Serial.print("st: [");
    Serial.print(st);
    Serial.println("]");

    float fx, fy;
    fx = xx.toFloat();
        Serial.print("xx: [");
    Serial.print(xx);
    Serial.println("]");

    fy = yy.toFloat();
        Serial.print("yy: [");
    Serial.print(yy);
    Serial.println("]");
    
    Serial.println(px);
    Serial.println(py);
    Serial.println(st.length());

    Serial.print("line(): x[");
    Serial.print(st.substring(px+1));
    Serial.print("]:");
    Serial.print(fx);
    Serial.print(" y: ");
    Serial.println(fy);
    //line(fx,fy);

    /*
    Serial.print("should be: ");
    Serial.print(extractValue(st, 'X'));
    Serial.print(" ");
    Serial.println(extractValue(st, 'Y'));
    */
  }
}
void setup() {
  Serial.begin(115200);
  delay(2000);
  // put your setup code here, to run once:
  nc("N17 G0 X-100.000 Y0.000 F3000.0*73");
}


void loop() {
  // put your main code here, to run repeatedly:

}