Correction signal input system for electronic timepiece
AssigneeCitizen Watch Co., Ltd.
InventorSizuo Yamaguchi
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Abstract
In an electronic timepiece having a central processing unit for processing current time and other data, and equipped with a crown and switch means coupled thereto for providing a correction signal comprising a pulse train of relatively high frequency, a bidirectional counter is provided for counting the correction signal pulses, with successive count totals in said counter being transferred in parallel form to be processed by the central processing unit. Processing of the high frequency correction pulses can thereby be performed even with the low maximum frequency which is generally available in an electronic timepiece for use as the clock signal to operate the central processing unit.
Claims2
In an electronic timepiece having a crown and switch means coupled thereto and responsive to rotation of said crown for producing correction data comprising a train of correction pulses, a source of a unit time signal, a central processing unit coupled to receive said unit time signal with said central processing unit being normally in a state of non-activation and being periodically activated to perform time data processing in response to said unit time signal, and display means for displaying time data produced by said central processing unit, a correction signal input system for supplying said correction data from said crown-coupled switch means to said central processing unit, comprising:
- counter circuit means coupled to receive said correction pulses, to count and temporarily store said correction data;
- zero detection circuit means coupled to said counter circuit means for detecting a condition wherein the contents of said counter circuit means are other than zero, and for producing an output indicative of the occurrence of said condition;
- and
- transfer gate circuit means coupled between output terminals of said counter circuit means and said central processing unit;
- said central processing unit being responsive to said output signal from said zero detection circuit means for being set into a state of activation and for generating a transfer enable signal when said state of activation has been attained, said transfer gate circuit means being responsive to said transfer enable signal for transferring the contents of said counter circuit means to said central processing unit to be processed thereby, said central processing unit further generating a counter reset signal after said transfer of said counter contents has been performed, said counter circuit means being responsive to said counter reset signal for being reset to a count of zero.
Dependencies are inferred from the claim text.