Apparatus for displaying time-of-day data adaptively to different time zones

• US 5,309,500 A
• Filed: 06/24/1993
• Issued: 05/03/1994
• Est. Priority Date: 09/07/1990
• Status: Expired due to Term

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Iguchi, Kazuaki, Koma, Noriko
• Primary Examiner(s): Kuntz, Curtis
• Assistant Examiner(s): CUMMING, WILLIAM D
• Application Number:
  US08/080,516
• Time in Patent Office: 313 Days
• Field of Search: 340/539, 342/457, 342/463, 368/47, 379/56, 379/57, 379/58, 379/59, 379/131, 379/433, 455/33.1, 455/58.2
• US Class Current: 455/566
• CPC Class Codes: G04G 9/0076 in which the time in another time-zone or in another city can be displayed at will
• CPC Class Codes: H04M 1/724 User interfaces specially adapted for cordless or mobile telephones

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.

Claims

1. A cellular mobile telephone set operable in a telephone mode and a time data display mode, said telephone set including a receiver for receiving area identifying codes transmitted from a cellular mobile communications system and a keypad, comprising:

a timepiece for constantly generating time-of-day data;

a memory;

write control means responsive to said receiver during said time data display mode for storing a plurality of successive time difference data entered from said keypad into said memory respectively corresponding to area identifying codes successively received by said receiver;

read control means responsive to said receiver during said time data display mode for recalling one of the stored time difference data from said memory corresponding to an area identifying code received by said receiver and modifying said time-of-day data with the recalled time difference data; and

a display for displaying the modified time-of-day data.

2. A cellular mobile telephone set as claimed in claim 1, wherein said read control means comprises means for comparing an area identifying code most recently received by said receiver with a previously received area identifying code and recalling said time difference data from said memory when said compared codes differ from each other.

3. A cellular mobile telephone set as claimed in claim 1, wherein each of the stored time difference data is indicative of a time difference of a local area with respect to a user'"'"'s home area.

4. A cellular mobile telephone set as claimed in claim 1, wherein said read control means comprises buffer means for storing time difference data recalled from said memory and adder means for combining data stored in said buffer means with the time-of-day data from said timepiece, said display unit displaying the combined data.