A control interface for a device is disclosed. The control interface has a display (302) for displaying a device control menu a rotary control dial (306) for operation by a user to navigate within the control menu and a menu control which causes entry to a menu list of the control menu to occur at a predetermined position in the menu list, determines at least one user parameter from operation of the control dial by the user in navigation of the menu, and applies the determined user parameter to subsequent operation of the control dial within that menu. Further disclosed is the apparatus for treating sleep disordered breathing comprising a flow generator for delivering a supply of breathable gas at positive pressure to a patient and the above described control interface.
