GB1391396A - Electronic watch - Google Patents

Abstract

1391396 Electronic watches CASIO COMPUTER CO Ltd 13 March 1973 [15 March 1972] 12065/73 Heading G3T An electronic watch having a digital numeric display is arranged to indicate the date on demand, using the same display elements as are used to indicate the time on demand. In Fig.2, a pulse generator 19 including a quartz crystal controlled oscillator feeds timing pulses at 1 Hz to a seconds counter 20 which produces a 1 minute carry signal every sixty pulses. The carry signals are fed to a minute counter 21 the content of which is applied to a digital display via AND gates 24, OR gates 25, a decoder 22 and a driver 18. Every sixty minutes the counter 21 sends a carry signal to an hours counter 23 the content of which is decoded at 26 and applied to the display via a driver 27. Carry signals from the hours counter 23 are fed to a binary counter 28 which produces a carry signal every 24 hours to a 31-step date counter 30 via an OR gate 29. When a date demand switch button is depressed, AND gates 31 pass the outputs of date counter 30 via the OR gates 25 to the decoder 22. At the same time the output from a NOT circuit 33 is blocked so that AND gates 24 are blocked and hence also the minutes signals from counter 21 to the decoder 22. Date indication is therefore displayed on the minute indicator (15) Fig.1 (not shown). Alternatively the date indication may be displayed on the hour indicator (14) Fig.1. The date indication may be advanced irrespective of the output from the binary counter 28, by operation of a date advancing button switch 34 which advances the count of the 31-step counter.