Patent ID: 7428065

Claim:
A printer for printing received print job data, comprising: time count means for setting of a reference date and time, measuring an elapsed time since the setting of the reference date and time, adding the elapsed time to the reference date and time to obtain a printer current date and time, and outputting the printer current date and time; allowable time storage means for storing an allowable time set by a user; rewriteable nonvolatile information storage means; event relevant information preparation means for preparing event relevant information comprising the printer current date and time obtained from the time count means each time an occurrence of an event is detected, and storing the event relevant information in the information storage means; and date and time adjustment means for executing a date and time setting process comprising: acquiring the printer current date and time from the time count means, acquiring an external apparatus current date and time from an external apparatus, setting the external apparatus current date and time as the reference date and time in the time count means, determining a next date and time to execute the date and time setting process so that the difference between an expected date and time obtained from the external apparatus and an expected date and time obtained from the time count means is less than or equal to the allowable time, wherein the determination is based on the external apparatus current date and time, the printer current date and time, the elapsed time, and the allowable time.