A system for controlling an apparatus (11, 21, 31), which system comprises a control unit (13, 23, 33) adapted to transfer control signals to the apparatus dependent on the control data. Said control unit comprises data input means (14, 24, 34, 44) to input said control data, and said apparatus comprises interpreting means adapted to translate said control signal into an action. Aiming to indicate for a user of the control unit, which action the apparatus is arranged to take when activating the data input means, a visual indicator is arranged on said data input means. The invention is characterized in that said data input means comprises a variable presentation means (45, 57), arranged to realise said indicator, wherein said control unit comprises a first storage means (53) adapted to store the visual data presentable with said presentation unit. Preferably, said control unit comprises several separate data input means, each provided with a presentation means, in which each presentation means comprises separate displays, arranged to present a picture dependent on said visual data.