| 摘要 |
PURPOSE:To prevent an erroneous input and to improve the reliability of an electronic timepiece by accepting exclusively the continuous input within a prescribed time interval when an input action is carried out with an external operation member having a revolution detecting means. CONSTITUTION:A clock 7 prevent the chattering of a switch 1 of a revolution detecting means with a rectangular wave of 128Hz obtained from a dividing circuit of a timepiece and in the form of clocks of FF3 and 4. When the switch 1 is instantly turned ON from an OFF state, a 1min timer consisting of D type flip-flops FF11-13 is reset. Then the Q output of the FF13 is set at H (VDD) to open an AND gate 8, and then the output Q dropped down to L (0V) after the 1min signals 10 are counted by two pulses (2min). Then the gate 8 inhibits the output of an AND gate 6. In other words, no input waveform appears to a signal 9 unless the switch 1 is turned on within 2min (at an error of 1-2min). This signal 9 is used as a command signal for the time correction, mode switching and other functions. |
