Sorting of name displays for use on building houses uses two groups with one group having non numeric symbols

摘要

The door system in a large building uses a controller (10) coupled to a bus (14) supporting loudspeakers (20,22). The controller has a display (12) of names. These are in two groups with some having non alpha numeric symbols (30) that aids children who cannot read. A second group has alphanumeric words (32).