steppermotor with big easy stepper shield and accelstepper library

Thanks Paul!

It is working now. I only had to change:

stepper.moveTo(pos);   
stepper.run();
      
         while (stepper.distanceToGo() != 0) 
             {}

into:

stepper.moveTo(pos);   
     
         while (stepper.distanceToGo() != 0) 
             {stepper.run();}

To make it work.

Thanks again.