Communication device with time adjustment function

A communication device comprising:

• time/date (T/D) data generating means for generating T/D data according to a calendar;
• storage means for edittably storing T/D data regarding a beginning and an end of a specified time period;
• judgement means for judging whether the T/D DATA generated by the T/D DATA generating means is in the specified time period;
• T/D DATA changing means for changing the T/D DATA of the T/D generating means to the T/D DATA corresponding to a preset T/D DATA when the judgement means judged that the T/D DATA generated by the T/D DATA generating means is in the specified time period;
• wherein the T/D DATA regarding the beginning and the end of the specified time period is set or replaced with a T/D DATA supplied from a communication center, the communication center judging whether or not an operation or adjustment in the T/D DATA of the communication device is properly performed based on the information regarding the adjustment operation in the T/D DATA transmitted from the communication device and the set/replacement of the T/D DATA regarding the beginning and the end of the specified time period is performed when the adjustment operation of the T/D DATA is not properly performed.