System for controlling a roll screen having a roller tube for receiving the winding the screen fabric of the present invention varies the rotational speed of the roller tube in order to achieve a constant screen ruling speed. Desired screen line speed, of the roller tube diameter, and the thickness and length of the screen fabric is stored in memory for use by the microprocessor. As being preferred, the rotational speed of the roller tube is varied by the microprocessor in accordance with the screen position determined by the signal from the Hall effect sensors. The microprocessor holds the counter number increases or decreases depending on the direction of rotation of the roller tube. Microprocessor based on the number counter, to determine the rotational speed corrected for the current screen position and desired screen ruling speed. As being preferred, the microprocessor controls the rotational speed of the roller tube by using a pulse width modulated signal. The first and second roll having first and second may be used to control the blinds or different thickness of the screen fabric, the system having a roller tube of different diameters of the present invention it may be used to control the screen.