Abstract:
In an electronic instrument having a keyboard including numeric keys for entering numerical data into the instrument and instruction keys for entering instructions into the instrument, there is provided a memory responsive to the operation of the numeric keys to store numerical data therein, an arithmetic operating circuit responsive to the operation of the instruction keys to operate on at least the numerical data, a time counter for counting time, and a setter for setting the initial value in the time counter in accordance with the numerical data entered by operation of the numeric keys.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to an electronic instrument dealing with a plurality of different systems of notation (or units). 
     2. Description of the Prior Art 
     There are commercially available electronic instruments capable of dealing with different systems of notation, such as electronic devices comprising a combination of a timepiece and a desk top calculator or electronic devices comprising a combination of a stop watch and a desk top calculator. However, these do not enable one to confirm time of day or measure time while effecting calculation. This is because they have only one display means and do not enable calculation and time of day or calculation and time to be seen at a time. 
     Also, such electronic instruments as those mentioned above have individual elements for dealing with respective systems of notation and rarely have a common element capable of dealing with different systems of notation. 
     SUMMARY OF THE INVENTION 
     In view of the above-noted points, it is an object of the present invention to provide an improved electronic instrument. 
     It is another object of the present invention to provide an electronic instrument which enables the initially set numerical data of a timepiece unit to be entered from the key input portion of a calculator unit having a key input portion. 
     It is still another object of the present invention to provide an electronic instrument having a data display portion concerned with operation of the calculator unit and a time-of-day display portion initially settable by the key input portion of the calculator unit. 
     It is yet still another object of the present invention to provide an electronic instrument having a first display portion for displaying a first system of notation and a second display portion for displaying a second system of notation. 
     Other objects of the present invention will become fully apparent from the detailed description of the invention taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a pictorial view showing an embodiment of the electronic device according to the present invention. 
     FIG. 2 is a block diagram of the embodiment shown in FIG. 1. 
     FIG. 3 is a view illustrating the operation of the same embodiment. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to FIG. 1 which is a pictorial view of the calculator as an example of the electronic device according to the present invention, a keyboard 1 includes a plurality of keys. Respective keys are used to designate various instructions such as numerical inputs, operating instructions, timing control instructions, etc. Operations of these keys will be briefly described below. 
     0, 1, 2, . . . , 9 numerical input keys 
     +/- key for converting the sign of numeral displayed 
     +, -, ×, ÷ arithmetic operations preset/operation executing keys 
     = operation executing key 
     M+ addition executing key for executing the addition of displayed data to the memory 
     RM memory call key 
     CM memory data erase key 
     CI displayed data (main displayed data) erase key 
     C erase key for clearing the content of the register concerned with operations 
     TC erase key for clearing the content of the register concerned with time 
     TI key for converting decimal data into time count data 
     S second numerical input designating key 
     M minute numerical input designating key 
     H hour numerical input designating key 
     Start U time count start key (up count) 
     Start D time count start key (down count) 
     Stop R time count interruption key (counter reset key) 
     Stop C time count stop key (continue count) 
     Stop P time count temporary stop 
     Rap D transfer instructing key for transferring time count data to the operational register 
     Rap M transfer instructing key for transferring time count data to the memory register 
     Set transfer instructing key for transferring the operational register data to the time count register (initial value set key) 
     Designated by 2a and 2b are display means responsive to operations of the above-described keys to display numerical data, and each of them comprises a plurality of juxtaposed segment type display elements. 
     Referring now to FIG. 2 which is a block diagram of the calculator shown in FIG. 1, a keyboard input unit KI generates coded signals corresponding to the keys. Designated by CU is a control unit for receiving signals from the keyboard input unit KI or signals from other circuits and for generating various control and data signals to be applied to circuits which will hereinafter be described. ROM is a memory which stores input sequence, data and operation control sequence. R1 is a register which receives data from the keyboard input unit KI at first. Registers R2 and R3 are used with the register R1 to store therein data during arithmetic operations. Register R4 is one which is commonly called an independent memory. Register R5 receives as input the data of hour, minute and second. Register 6 also receives as input the data of hour, minute and second. Designated by ADC is an arithmetic control unit which causes the contents of the registers R1, R2, R3 to be calculated under the instruction from the control unit CU. COV1 is a converter circuit for converting the data of the register R6 into the unit of second or for converting the serial data of the register R6 into parallel data. Designated by TCU is a time count circuit for counting the pulses of clock OSC. 
     When the converter circuit COV1 effects conversion of serial data into parallel data, two sexagesimal counters and one quatrevigesimal counter are series-connected together in the counter unit and such unit counts the pulses of the aforementioned clock. 
     Designated by COV2 is a converter circuit for converting the data of the time count circuit TCU into a form of display. When the time count circuit TCU comprises two sexagesimal counters and one quatrevigesimal counter, the converter circuit COV2 performs parallel-to-serial conversion. Display units DP1 and DP2 are provided with the display means 2a and 2b as shown in FIG. 1. 
     Control circuit CCU controls the delivery of the content of the converter circuit COV1 to the time count circuit TCU. Timer TMR receives a signal responsive to the key TI and generates a scanning signal. 
     Flip-flops F1-F13 are set and reset by the signal from the control unit CU. There are further seen AND gates G1-G19, OR gates OG1-OG10 and inverter i. 
     Operation of the present embodiment constructed as described will now be discussed. The case of measuring the calculating speed of the operator is taken as an example. 
     First, keys &#34;C&#34;, &#34;CM&#34; and &#34;TC&#34; are operated to clear the calculator. 
     Next, the following key operations are effected to enter 12 hours 45 minutes and 30 seconds as the count starting time. 
     Keys &#34;1&#34; and &#34;2&#34; are first operated, whereby signals corresponding to these keys are generated from the keyboard input unit KI and discriminated by the control unit CU. As the result, data corresponding to the keys &#34;1&#34; and &#34;2&#34; are applied to the register R1 through the AND gate G5, and the data so applied are displayed on the display unit DP2 through the AND gate G16. 
     Subsequently, the hour numerical input key &#34;H&#34; is operated, whereby a signal is put out from the terminal H of the control unit CU and the data &#34;12&#34; of the register R1 is stored into the section A of the register R5 through the AND gate G12. Also, the Q output of the flip-flop F12 is set to 1 and the content of the register R5 is displayed on the display unit DP2 through the gate G15, in the manner as shown in FIG. 3(2). 
     Next, when keys &#34;4&#34; and &#34;5&#34; are operated, the control unit CU responds to the operation of these numeric keys to generate to a signal for rendering the Q output of the flip-flop F12 to &#34;0&#34;, and this Q signal clears the content of the register R1. After the aforementioned control, the data corresponding to keys &#34;4&#34; and &#34;5&#34; are applied to the register R1 and displayed on the display unit DP2 through the AND gate G16, in the manner as shown in FIG. 3(3). 
     The minute numerical input key &#34;M&#34; is operated, whereby the data &#34;45&#34; of the register R1 is caused by the signal from the control unit CU to enter the section B of the register R5 through the AND gate G13. The signal from the control unit CU also renders the Q output of the flip-flop F12 to &#34;1&#34;, and causes the content 124500 of the register R5 to be delivered to the display unit DP2 through the AND gate G15. 
     If keys &#34;3&#34; and &#34;0&#34; are then operated, a similar operation to that described above takes place and upon operation of the second numerical input key &#34;S&#34;, the data &#34;30&#34; of the register R1 is applied to the section C of the register R5 through the AND gate G14 and display of 124530 takes place on the display unit DP2. 
     When the key &#34;SET&#34; is operated, the Q output of the flip-flop F11 becomes &#34;1&#34;. Accordingly, the content of the register R5 enters the register R6 through the AND gate G3 and is displayed on the display unit DP1. At the same time, the content of the register R6 enters the converter circuit COV1 and passes therethrough to be set by the time count unit TCU. The content so set is passed through the converter circuit COV2 and the AND gate G2 to the register R6, and displayed on the display unit DP1. 
     When the operator operates the key &#34;START U&#34;, the time count unit TCU starts counting the output signals of clock OSC with the preset 124530 as the initial value, and the contents of the time count unit TCU are successively passed through the converter circuit COV2 and the AND gate G2 to the register R6 and the display unit DP1, whereby lapse of time is displayed from moment to moment. 
     If, during the above-described operation, the operator carries out a calculation such as, for example, 10.3+2.045=, then the following process will take place. 
     Upon operation of numeric keys &#34;1&#34;, &#34;0&#34;, &#34;.&#34; and &#34;3&#34;, the Q output of the flip-flop F12 is rendered to &#34;0&#34; and the content of the register R1 is displayed on the display unit DP2, while the data stored in the register R1 before the key operation is cleared and data &#34;10.3&#34; comes to be stored in the register R1. 
     When the key &#34;+&#34; is operated, the data in the register R1 is transferred through the gate G8 to the register R2. 
     Next, when numeric keys &#34;2&#34;, &#34;.&#34;, &#34;0&#34;, &#34;4&#34; and &#34;5&#34; are operated, the content of the register is cleared by the first of these numerals and the data &#34;2.045&#34; is applied to the register R1. 
     The operation executing key &#34;=&#34; is depressed, whereby the contents of the register R1 and R2 are added together in accordance with the add instruction, and the result of the addition is stored in the register R1 and displayed on the display unit DP2. If the display means 2a is then diplaying 124601, it can be seen that the time is 12 o&#39;clock 46 minutes 1 second. When the key &#34;STOP C&#34; is depressed, the Q output of the flip-flop F2 is rendered to 0 and the AND gate G2 is closed, so that the time being displayed remains unchanged. 
     The key &#34;STOP R&#34; is depressed, whereupon the Q output of the flip-flop F3 becomes &#34;1&#34; and the time count unit TCU and the converter circuit COV2 are both cleared while the AND gate G2 is closed by the Q output of the flip-flop F3, so that the point of time whereat the key operation has taken place is displayed. 
     When the key &#34;STOP P&#34; is depressed, the Q output of the flip-flop F13 becomes &#34;0&#34; and the Q output of the flip-flops F5 and F6 are interrupted by the gates G17 and G18, so that the time count unit TCU stops counting. 
     The key &#34;START D&#34; serves to cause the time count unit TCU to count down. 
     The above-mentioned keys will further be described. Upon operation of the key &#34;START D&#34;, the flip-flop F5 is set and the Q output thereof is applied to one end of the AND gate G17, while the Q output of the flip-flop F13 becomes &#34;1&#34;, whereby a signal meaning count down is applied to the count down terminal &#34;down&#34; of the time count unit TCU. Upon application of such down signal, the time count unit TCU starts counting down from a set value, so that the display means 2a displays the count down as it goes on. 
     Key &#34;Rap D&#34; serves to render the Q output of the flip-flop F7 to &#34;1&#34; and to apply the time data of the register R6 to the register R1. 
     This key will further be described. Upon depression of the key &#34;Rap D&#34;, the flip-flop F7 is set by the signal from the control unit CU and the content of the register R6 is stored into the register R1 through the AND gate G4 and the OR gate OG9, and such content is displayed on the display means 2b through the AND gate G16. 
     Key &#34;RM&#34; serves to render the Q output of the flip-flop F8 to &#34;1&#34; and to apply the content of the register R4 to the register R1. 
     Key &#34;Rap M&#34; serves to render the Q output of the flip-flop F9 to &#34;1&#34; and apply the content of the register R6 to the register R4 for preservation therein. 
     Key &#34;M+&#34; serves to render the Q output of the flip-flop F10 to &#34;1&#34;, to transfer the content of the register R1 to the register R2, to transfer the content of the register R4 to the register R1, to sum the contents of the registers R1 and R2 and cause the register R4 to store the sum. 
     Key &#34;TI&#34; serves to deliver the data stored in the register R1 to the register R5. Upon operation of this key, the control unit drives the timer TMR so that three output lines thereof put out scanning signals with predetermined time intervals therebetween, thus distributing the data of the register R1 into the sections A, B and C of the register R5 in accordance with the scanning signals.