JPS62245359A - Electronic calculator - Google Patents

Abstract

PURPOSE:To easily recognize a numeric value including a decimal point, by constituting respective display digit in a display unit of various sizes of display segments, and driving selectively the display segment on the basis of the detection of a decimal part. CONSTITUTION:Respective display digit is constituted of various kinds of squarish 8-shaped segments, and respective segment is constituted of three segments 1A-8A, 1B-8B, and 1C-8C, for each display digit, and five common electrodes C1-C5 coupled commonly over all of the display digits. Based on the detection of the decimal part by a decimal part detection circuit, an integer part is displayed in a large size of squarish 8-shaped segment, and the decimal part is displayed in a small size of squarish 8-shaped segment.

Description

[Detailed description of the invention] (b) Industrial application field The present invention relates to an electronic desktop calculator.

(b) Conventional technology In general, in electronic desktop calculators, in order to be able to display numbers including Komaki points or calculation results including small fault points, the display is equipped with Japanese characters segments as well as small fault points. A dot segment is provided for each display digit, but conventionally when displaying numerical values that include a decimal point, only the Komaki point segment is lit. There was a problem that it was easy to mistakenly recognize the
(See Publication No. 16153).

Problems to be solved by the invention H The present invention was made to solve the above-mentioned problems. By changing the shape of the numerical value after the decimal point, it is easier to recognize numerical values including small fault points and to prevent misreading. The present invention provides an electronic desktop calculator that prevents such problems.

B) Means for Solving the Problems The present invention comprises each display digit of a display device with large and small display segments, and also includes a small part detection circuit and a circuit for selectively driving display segments based on the detection of the decimal part. It is composed of

(E) Function Since the present invention is configured as described above, in the case of a numerical value that includes a small error point, the ritual part is displayed in a large display segment, and the decimal part is displayed in a small display segment. It is easy to recognize that the numerical values include points. EXAMPLES Examples of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the components of the electronic desktop calculator of the present invention. (1) is a keyboard consisting of a useless numeric keypad for V1 and function keys for instructing calculations. 12
) is an arithmetic control circuit that performs arithmetic processing based on key No. 43 from the keyboard (1) and generates display output. (
3) is a liquid crystal display based on the display output signal of the arithmetic control circuit (2)! ! 514).

<5) is a decimal part detection circuit that detects the small part of the numerical value input from the keyboard (1) and the calculation result processed by @non-control circuit (2), and the point kakunta that counts the small fault position is Counting starts from the time when the arithmetic control circuit 12) detects the operation of the decimal point key on the keyboard (1), and counts and stores the number of digits below the small fault point. Further, when a calculation process is performed, the point force kunta is changed accordingly and the decimal point position for the calculation result is stored.

(6) is a segment selection circuit which outputs to the liquid crystal drive circuit (3) a switching signal for switching and selecting which display segment is to be driven based on the output of the small area detection circuit (5).

The arithmetic control circuit (2), liquid crystal drive circuit (3), small #, part detection circuit 151, and segment selection circuit (6) are one L
It is integrated and configured in SI.

Figure 2 is a diagram showing the structure of the display segments of the liquid crystal display/41. Each display digit is composed of large and small Japanese character segments, and each segment has three segment electrodes for each display digit connected by broken lines. (A, B, C), and five common electrodes (01 to C5) commonly connected to all display digits by solid lines.
). Each segment is turned on when a voltage of 3V is applied between the segment electrode and the common electrode, and is turned off when the voltage between the electrodes is Ov or 1.5V. Which segment is lit is determined by the display output of the arithmetic control circuit 1M (21) and the segment selection circuit (6
) LCD drive circuit based on the output signal! 3) A predetermined liquid crystal drive circuit is generated.

Next, the operation of the present invention having the following configuration will be explained.

First, if an integer such as r123456J is entered from the keyboard (1), there is no operation of the decimal point key, so the point kakunta of decimal part detection circuit < 51 does not operate and the segment selection circuit (6) inputs the large Japanese character. Since the code 9I for selecting the segment is output, it is displayed on the Kg1 product display 14) as shown in FIG.

On the other hand, if r121.456J including the decimal point is entered, the point kakunta of the small greed part ejection circuit (5) starts counting by operating the small fault key and is input to the first peak after the decimal point key. Count the number of digits in a numerical value. At the start of counting point kakunta, the segment selection circuit (6) switches to drive the small Japanese segment and outputs No. 4 to the liquid crystal drive circuit (3), so the small segment is small as shown in Figure 4. It is displayed numerically. Figure 5 shows the voltage applied to the common electrodes (C1 to C5) and the voltage waveform applied to the segment electrodes of each display digit when displaying as shown in Figure 4. Regarding the calculation result, the segment selection circuit (6) generates a switching equal sign based on the value of the point kakunta of the decimal part detection circuit + 51, and the value of the small part is reduced in the same way as described in 1ilf. It can be displayed.

In the above-mentioned embodiment, the large and small Japanese character segments of the display ffl'41 have a common d segment as shown in FIG. 2, but they have a common g segment as shown in FIG. It is also possible to do this, and other modifications are also possible.

(G) Effects of the Invention As mentioned above, the electronic desk calculator of the present invention makes it easy to calculate am, which is a 712 error value including a small error point, by making the shape of the numerical value of the Komaki part different from the case & part. This has the effect of making the numbers easier to read and eliminating misreading.

[Brief explanation of drawings]

! Figure 1 is a block diagram showing the configuration of the electronic desktop calculator of the present invention, Figure 2 is a plan view showing segment electrodes of a liquid crystal display, Figures 6 and 4 are diagrams showing display examples, and Figure 5 is a A liquid crystal drive signal waveform diagram, FIG. 6 is a cross-sectional view showing another embodiment of segment electrodes of a liquid crystal display. (1)...keyboard, (2)...arithmetic control circuit,
<3)...Liquid crystal drive circuit, 14)...Liquid crystal display,
(51... Decimal part detection circuit, (6)... Segment flesh plate circuit.

Claims (1)

[Claims] (1) A keyboard for inputting numerical values, an arithmetic control circuit that performs arithmetic processing based on the input numerical data, and each display digit consists of large and small Japanese character segments to display the entered numerical values and the calculation results. It consisted of a display, a circuit for detecting the decimal part of the entered numerical value and the calculation result, and a display driving means for driving a display digit corresponding to the decimal part to light up a small Japanese character segment when the decimal part is detected. An electronic desktop calculator characterized by: