Abstract: Index letters representing different groups of dial memories are stored in an index letter memory. One of the dial memories is displayed on a display to be a starting memory, when a reference requesting signal is supplied from a key input unit to a whole memory or skip reference portion of a central processing unit, so that a whole memory or skip reference mode is carried out to refer to a dial memory indexed in each of the different groups by each of the index letters in a forward or reverse direction from the starting memory to following dial memories. In the whole memory reference mode, dial memories indexed by the index letters are referred for continuous groups of dial memories. In the skip reference mode, index letters of a number "n" are skipped in accordance with the pressing-on of a skip reference key provided in the key input unit by "n" times, so that a dial memory corresponding to an index letter following the skipped index letters is referred to be displayed on the display.

Abstract: A cellular mobile station is operable in a telephone mode and a time data display mode. During the time display mode, the station constantly receives an area identifying code transmitted from a cellular mobile communications system. On crossing a boundary between adjoining cell-site areas, a time difference value is entered from a keypad into a location of a memory corresponding to the received code. This process is continued on a learning basis to store as many time difference values into the memory as there are cell-site areas along the route of a journey. Following the learning process, the station constantly receives an area identifying code and recalls one of the stored time difference data from the memory corresponding to a code received on crossing a boundary and modifies displayed timepiece data with the recalled time difference.

Abstract: A cellular mobile station is operable in a telephone mode and a time data display mode. During the time display mode, the station constantly receives an area identifying code transmitted from a cellular mobile communications system. On crossing a boundary between adjoining cell-site areas, a time difference value is entered from a keypad into a location of a memory corresponding to the received code. This process is continued on a learning basis to store as many time difference values into the memory as there are cell-site areas along the route of a journey. Following the learning process, the station constantly receives an area identifying code and recalls one of the stored time difference data from the memory corresponding to a code received on crossing a boundary and modifies displayed timepiece data with the recalled time difference.

Abstract: A control signal generator is provided to supply a control signal to a control unit of a telephone set having dial memories. Information stored in a memory in the dial memories is forbidden to be erased, unless the control signal is supplied to the control unit. As a result, important information is protected from erroneous erasing in the dial memory.

Abstract: In an apparatus for driving a service function unit of a multi-function telephone set, each service function is carried out by pushing one hardware type programmable key. The pushing of the programmable key is to read programmed service information stored in a memory, and to process the read service information, so that the service function is easily carried out by a single key operation by a user of the telephone set.