| 摘要 |
An electronic analog wristwatch includes an alarm which is set by rapidly, electromechanically driving the watch hands forward proximate to the desired alarm time, slowly advancing the hands electromechanically to the exact alarm setting, and then rapidly returning, by electromechanically driving, the hands to the actual present time. A counter records the number of drive pulses required to advance the hands to the alarm setting, while another counter records the time elapsed, measured in pulses, in setting the alarm including advancement and return of the hands. The number of pulses required for hand advancement is stored in memory. The pulses required for hand return are counted until the sum of the hand returning pulses and the elapsed time pulses equals the number of pulses which were required for advancing the hands, as stored in memory. At this time the watch is switched into its normal timekeeping mode, and the number of pulses required for return of the hands from the alarm setting to the actual time is stored in memory. The alarm is activated when a coincidence detector indicates that the number of real time pulses after return of the hands equals the count stored in memory.
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