| 摘要 |
In a digital watch, frequency adjusting can be achieved by selectively deleting pulses at a specified location in the divider chain in order to obtain the desired timekeeping accuracy. When a digital watch's recessed (setting) push button is sequentially depressed, the watch's display advances through the month, date, hours and minutes/seconds setting modes. If the recessed push button is depressed again, the watch will be in the coarse frequency adjust mode and the letters "CFA" are shown on the watch display for approximately one second, the display is blanked for 0.5 second, and then the watch shows a three digit frequency correction number with the first two digits flashing. By holding down a main operating push button, the flashing number increments at a one Hertz rate until the desired coarse frequency correction number is shown on the watch display. An additional push of the recessed push button puts the watch in the fine frequency adjust mode and the letters "FFA" are shown on the watch display for approximately one second, the display is blanked approximately 0.5 seconds, and the same three digit frequency correction number appears with the last digit flashing. By holding down the main push button, the flashing digit is incremented at a one Hertz rate until the desired fine frequency correction number is obtained at which time the main push button is released.
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