DATA DISPLAY DEVICE

A visual display apparatus comprises a multisegment bar display (2) having display characters (16) divided into two groups. In the first group individual outer segment bars (17) are each associated with a respective permanent marking which indicates a specific information item or class of information items, and are connected in a closed cycle whereby the instantaneously actuated display can be advanced forward or backward in the closed cycle from one segment bar (17) to another by keys (4,5). A sequence of display patterns representing parameter values is displayed in the second group of display characters (16), which sequence and which set depends on the segment bar (17) which is instantaneously actuated in the first group, and a desired parameter value can be selected from among the sequence by depressing an "acceptance" key (6). The parameters for equipment can be adopted rapidly and under conditions of rapid surveyability, whereby a selection for each of a number of parameters can be made from a plurality of parameter values, so that the parameters can be set in advance of an operation phase.