JPS6146866B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electronic desktop calculator that can count the number of electrical pulses and perform display, calculation, etc. in the same way as a number entered on a keyboard.

In general electronic desktop calculators, calculations are performed based on numbers entered on the keyboard. However, this type of calculator is equipped with a means to generate pulses independently of the numeric keypad, or a means to receive pulses from an external device, and it is possible to count and display the pulses, or to input the counted value and the keyboard. There is a growing need for something with a function to calculate numbers. For example, when measuring the distance between two points on a map, you can trace the line connecting the two points with a roller that generates pulses at every predetermined angle of rotation, and input the generated pulses into a register. For example, by inputting the scale on the keyboard and calculating the product of the two numbers,
Distances can be measured very easily.

The present invention seeks to provide an electronic desktop calculator that can be used in this type of device.

Examples thereof will be described below with reference to the drawings. In FIG. 1, 1 is a keyboard of the calculator, 2 is a numeric value and arithmetic command circuit, 3 is a control circuit, 4 is an arithmetic register, and 5 is a display circuit including a display for displaying the contents of the display register 14. Note that 1 to 5 and 14 described above are the same as those provided in a normal calculator. A signal generator 6 generates an electrical signal, which generates an H or L signal as the switch 6a opens or closes. 7 is a mismatch detection circuit that detects a mismatch state between two inputs and generates a pulse; 8 is a flip-flop that inverts and outputs the state of this mismatch detection circuit 7; and 9 enters a calculation mode when a numeric operation command from the keyboard 1 is activated. , and flip-flops 10 and 11 that store the count mode when the pulses are counted.
12 is a 1 addition circuit that adds 1 to the count number of display register 14, and 13 is a numeral circuit that sets 1.

Next, the operation of the embodiment having the above configuration will be explained using the timing chart shown in FIG.

In FIG. 3, A is the output of the signal generator 6, B is the output of the mismatch detection circuit 7, and C is the output of the flip-flop 8. In FIG. 3, when the time timing is before t _a , the two inputs of the mismatch detection circuit 7 are each at a low level, so the output is at a low level as shown in FIG. Next, the output of the signal generator 6 changes from Low to High at time timing _ta . On the other hand, since the output of the flip-flop 8 does not change, the mismatch detection circuit 7 recognizes that the two inputs do not match, and outputs a high level output with a delay of time _t1 . Here, the delay of _t1 is considered as a type of gate delay time. When the output of the mismatch detection circuit 7 rises in this manner, the flip-flop 8 detects this rising edge and inverts the output after a delay of time _t2 .
The delay of t ₂ is also considered as a type of gate delay time.

In this way, the output of flip flip 8 is also High.
When the level is reached, both inputs of the mismatch detection circuit 7 become High level, so the mismatch detection circuit 7
becomes Low level again with a delay of time t ₁ . In this manner, the mismatch detection circuit 7 and the flip-flop 8 generate one pulse each time the level of the output of the signal generator 6 is inverted.

If the flip-flop 9 is now in the calculation mode, the pulse output from the mismatch detection circuit 7 converts the flip-flop 9 into the counting mode through the gate 11 and erases the calculation result stored in the display register 14. At the same time, 1 is placed in the display register 14 by the function of the 1 setting circuit 13. Further, when the flip-flop 9 enters the counting mode, the gate 10 is opened and the gate 11 is closed. Therefore, the pulses subsequently generated from the mismatch detection circuit 7 are passed through the gate 10 to the 1 addition circuit 1.
2, and the contents of the display register 14 are incremented by 1 each time the pulse is added. That is, the number of pulses generated by the mismatch detection circuit 7 is stored in the display register 14 and displayed by the display circuit 5.

Furthermore, if the flip-flop 9 is already in the counting mode when the first pulse is generated from the mismatch detection circuit 7, the first pulse is generated by the gate 10.
is added to the 1 addition circuit 12 via the 1 addition circuit 12, and added to the contents already stored in the display register 14. When the calculator key is input after pulse counting is completed in this way, the flip-flop 9 is reset and enters the calculation mode.

The pulses are counted in this way by the circuits 6 to 13, and the results are only stored in the display register 14, and the state of the calculator control circuit 3 is not changed, so the counted value is stored in the calculator. It can be used for calculations in the same way as numbers entered using the number keys.

FIG. 2 shows the actual operating status of this device and the display by the display circuit 5.
Input "12345×" by signal generator 6
The result of 21 operations is "259245". Further, by operating the signal generator 6 11 times, inputting "x" using the keyboard 1, further operating the signal generator 6 16 times, and inputting "=" using the keyboard 1, "176" is displayed.

As is clear from the above description, according to the present invention, it is possible to count pulses and display the value, and to perform arbitrary calculations using the value entered on the keyboard and the counted value of the pulse. can.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an electronic desktop calculator according to an embodiment of the present invention, FIG. 2 is a diagram showing its operating method, and FIG. 3 is a timing chart thereof. 1... Keyboard, 4... Arithmetic register, 5...
...display circuit, 7...mismatch detection circuit, 9...flip-flop, 10, 11...gate, 12...
1 addition circuit, 13...1 digit circuit.

Claims (1)

[Scope of Claims] 1. An electronic desktop calculator having a keyboard, a numerical value and arithmetic instruction circuit, a control unit, an arithmetic register, a display register, and a display, which is reset (or set) by applying an input signal from the keyboard. , a flip-flop that is set (or reset) by the generation of an execution instruction for the 1-digit circuit that places 1 in the display register, a pulse generation circuit that generates pulses to be counted, and a flip-flop that is reset (or reset) by the above flip-flop. ) for generating the execution command when the output pulse of the pulse generation circuit is applied when the flip-flop is set (or reset); and means for adding 1 to the contents of the display register when the output pulse of the pulse generation circuit is applied when the flip-flop is set (or reset).
An electronic desktop calculator equipped with an adding circuit. 2. As a pulse generation circuit, a signal generator that generates two types of signals with different levels by the opening and closing operations of a switch, a discrepancy detection circuit to which the output signal of this signal generator is added as one input, and a The electronic desktop calculator according to claim 1, characterized in that a flip-flop is used whose output is inverted by the output of the responsive discrepancy detection circuit, and whose inverted output is used as the other input of the discrepancy detection circuit. .