Timekeeping device
AssigneeKabushiki Kaisha Suwa Seikosha
InventorEisaku Shimizu
Life of this patent
Estimating the term…
Abstract
An electronic timekeeping device performs timekeeping functions and on command selectively outputs a plurality of data signals and performs supplemental functions for an external unit such as a microcomputer. Control signals inputted via a data bus from the external unit actuate switch means which selectively permit the external unit to command the timekeeping device to output required data signals or perform a particular function. The basic timekeeping circuits of the device continuously perform the timekeeping function regardless of the data signals or functions which have been commanded for output, and when the external unit is inoperative. Data signals from the external unit can also be input to modify the data output of the timekeeping device. Individual data buses within the timekeeping device are devoted to particular functions.
Claims20
A timekeeping device comprising:
- oscillator circuit means generating a high frequency standard signal;
- a divider network dividing down said standard signal and outputting lower frequency signals;
- a plurality of functions, said plurality of functions having data input signals and outputs, at least a portion of said functions having inputs derived from said divided down standard signals;
- means for individually addressing said plurality of functions by an external unit, said means for addressing including a first data bus interconnecting at least a portion of said plurality of functions;
- means for transmitting to said external unit said output signals from said functions, said means for transmitting including a second data bus interconnecting at least a portion of said plurality of functions;
- switch means, said switch means being positioned intermediate said external unit and said plurality of functions and being adapted for selectively connecting said first data bus or said second data bus to said external unit, said external unit addressing and reading said functions without time restriction of access nor interruption of said functions,
- said external unit operating at speeds unlimited by need for access to said function signals.
A timekeeping device adapted for coupling to an external unit for data communications comprising:
- divider means for dividing a standard signal;
- a plurality of counters for timing the frequency-divided signal from said frequency dividing means including read and write means for timing information;
- data buses connected with the read and write means of each of said counters;
- counter selecting means for selectively connecting said counters with said data buses;
- data input and output means for connecting said data buses and said counter selecting means with an external unit for data communications said external unit being connected with said counters without time restrictions of access;
- and signal control means coupled to said input and output means for controlling the content and the output from said counters.
Dependencies are inferred from the claim text.