Brinarpi:
So as I good understand, you suggest to me that from my own force come on result, that the motor can stop after the predefinied counts from encoder, and the speed can be regulate by pwm.To do that, I need to remove all other movements, and keep only one(to be simple).
Your English can be hard to understand so I am never sure if my answers are responding to the question you think you are asking.
My suggestion in Reply #25 was to write a short program that only moves the motor in one direction and causes it to stop after some number of encoder steps. If you choose a number of steps that corresponds exactly with a number of revolutions it will be easier to see if the motor is stopping in the right place.
In this simple program use analogWrite() to control the speed at a constant slow speed. There will be no need to change the value used for analogWrite() once you have identified a value that gives reliable slow running.
...R