JPS61275959A - Electronic calculator with graphic display function - Google Patents

Abstract

PURPOSE:To make a displayed graph easy to see by providing the function which calculates positions of axes of coordinates and measures in accordance with a preliminarily set range of a variable and displays axes of coordinates and measures on a graph display part. CONSTITUTION:A memory part 3 consists of a RAM and has registers 3A-3P. Each data of a functional formula inputted from a key input part 1 is written in an address of a numerical formula buffer 7 indicated by an execution pointer 4 and is read into an calculation part 5. The part 5 uses registers 3A-3P of the memory part 3 to execute the calculation under the control of a control part 2. Data for graph display and display of axes of coordinates and measures are read out from the memory part 3 and are sent to a graph display buffer 6A of a display buffer part 6 when the functional calculation is executed, and data for display of normal numerical values are sent to a text display buffer 6B in case of display of normal numerical values, and a graph or numerical values or the like are displayed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a small electronic calculator having a function of displaying a functional formula in a graph.

[Prior Art] Conventionally, small electronic calculators capable of displaying graphs corresponding to functional formulas have been considered. In this type of calculator, when displaying a certain functional formula y=f(x) as a graph, the independent variable It is something.

This calculator displays only the graph of the functional formula on the display.

[Problems with the Prior Art] However, in the case of the conventional calculator described above, the coordinate axes were not displayed, so it was difficult to know the roots of the displayed graph and the number of roots, which was very inconvenient.

[Objective of the Invention] It is an object of the present invention to provide a small electronic calculator having a graph display function that can display coordinate axes and their scales and make graphs easier to see.

[Key Points of the Invention] Coordinate axes (X-axis, Y-axis,
The coordinate axes and scale positions are calculated and the coordinate axes and scales are displayed on the graph display section.

[Example] Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

Figure 1 is a circuit diagram of a small electronic calculator equipped with a graph display function. In Figure 0, keys numbered 1 include the numeric keypad IA and function keys IB, which are provided on a normal calculator.
, Function key IC1 for inputting the function formula, Graph key ID to specify the graph display mode of the function formula, Range key IE to specify the input mode for each range data of variables X and Y included in the function formula, Function At least an EXE C execution) key IF for instructing execution of calculations, etc. is provided, and signals from each key are sent to the control unit 2 and processed.

The control section 2 consists of a ROM (read only memory) that stores programs for controlling all operations of this computer, and provides various control signals to the memory section 3, execution pointer 4, calculation section 5, and display buffer section 6.

The memory unit 3 consists of a RAM (random access memory), which includes an A register 3A, a B register 3B, and a pointer register 3C1 in which the execution pointer set by the control unit 2 in the execution pointer 4 when performing a function operation is temporarily saved. Previous coordinates (xo
, Vo ) are set respectively in the Xo register 3D.
, yo register 3E, X register 3F where the current coordinates (x, y) are set, V register 3G, X5ln where the minimum and maximum values of the range of variable X are set, respectively.
Register 3H, X5ax Register 3I, where the minimum and maximum values of the range of variable y are set, respectively. X sea written. register 3
N. (Each has a /+ie*o register 3P.

Each data of the function formula inputted from the key input unit 1 is written to each address of the formula buffer 7 indicated by the execution pointer 4, and then read into the calculation unit 5.

The calculation unit 5 calculates the function formula from the formula buffer 7 through each of the registers 3A to 3A of the memory unit 3 under the control of the control unit 2.
Execute using 3P. When executing a function calculation, the calculation unit 5 reads data for displaying the graph, coordinate axes, and scale from the memory unit 3 and sends it to the graph display eight buffer 6A in the display buffer unit 6, and also displays normal numerical values, etc. When performing this, the data for that purpose is sent to the text display buffer 6B, and the display data is sent to the display section 7, where graphs, numerical values, etc. are displayed.

The display unit 8 consists of a liquid crystal display device, for example, and has 96 pixels in the X direction.
Data is displayed using a matrix type dot display (coordinate points) of 64 dots in the Y direction.

Next, the operation of the above embodiment will be explained by taking as an example the case where the function formula % formula % (1) is calculated and the result is displayed in a graph, and with reference to FIGS. 2 to 12.

In this case, the range key IE and numeric keypad I of the key manual section 1 are
By manipulating A in advance, as shown in Figure 5, X +IIn
Register 3H. Preset the minimum and maximum values of the range for variable X in the X5ax register 3I, for example, -180 and 180, and in the ysin register 3J,
Similarly, in the Vmax register 3K, each data of the minimum value and maximum value of the change range for the variable y, for example, -2.2, and in the X SCL register: 13I- and the ysct register 3M, scale data, for example, 90.0.
5 is preset.

Next, enter the function formula (1) above using the graph key ID, function key 1c, function key 1B, numeric keypad LA, and EX.
When input by operating the E key IF, each data of the function formula of formula (1) is written into addresses O to 4 of the formula buffer 7, addressed by the execution pointer 4, as shown in FIG. . In addition, the data rEN of execution pointer "4"
D" is END code data written when the EXE key IF is operated. Then, according to the operations according to the flowcharts of FIGS. 7 to 12, the calculation unit 5 (
1) Functional calculation of the equation and calculation for displaying its coordinate axis and its scale are performed, and the resulting graph is displayed on the display section 8 as shown in Fig. 2. In other words, the main flow shown in Fig. 7 , when a graph command is input, first, an operation to determine whether there is data in the graph display buffer 6A is executed, and since there is currently no data, the process advances to step G2, where the 'lee register 3P is cleared, and then Y coordinate calculation is executed in step G3. Next, in step G4, it is determined whether the data in the y register 3G is rFFJ. So now N
Since it is O, proceed to step G5 and set the coordinates (0, y), (
95, draw a line between the two points in y).

In the example shown in FIG. 5, the y coordinate becomes "32" from the calculation shown in FIG. Next, the X1e register 3N is cleared in step G6, the X coordinate calculation is executed in step G7, and the process then proceeds to step G8. It is determined whether the data in the X register 3F is rFFJ, and if NO, step Proceed to G9, coordinates (X, 0), (X, 63) + 7)
Draw a line between the two points. In the example shown in FIG. 5, the X coordinate is "48" from the calculation shown in FIG.

Next, the process proceeds to step G10, where the scale processing shown in FIG. 10 is performed to calculate the scale, the process proceeds to step Gll, where the graph processing shown in FIG. 11 is performed, and the process proceeds to step G12, where a graph screen is displayed.

Note that in step G4, if the data in the y register 3G is rFFJ, it is an error, so step G6
If the data in the X register 3F is "rFF" in step G8, it is an error, and the process proceeds to step G10.

Next, the Y coordinate calculation in step G3 will be explained with reference to the flowchart of FIG.

First, in step Y1, calculation of the formula for determining the value of the Y coordinate shown in the figure is executed according to the data set in the ymemo register 3P, the Ysin register 3J, and the 7sax register 3K, and the resulting data is y.
Set in register 3H.

Next, in step Y2, the set data is rounded off to an integer, and then in step Y3,
The integer data is r of the minimum position coordinate in the Y coordinate direction.
It is determined whether or not it is smaller than OJ. If YES, the process advances to step Y4, where hexadecimal data "80H" is set in the y register 3G (step Y4), and the process ends. The meaning of this hexadecimal data r80++J is that the data structure of the y register 3G, etc. is an 8-bit structure, as shown in FIG. 4, and its most significant bit is 0VERR.
This is for the ANGE/UNDERRANGE flag, and in this case, the flag "1" indicating UNDERRANGE is written in that flag bit. Furthermore, minimum coordinate data rQJ is written into the lower 7 bits of the y register 3G.

On the other hand, if NO in step Y3, the process further advances to step Y5, where it is determined whether the above-mentioned integer data is larger than the maximum position coordinate "63" in the Y coordinate direction, and YES.
When , proceed to step Y6 and set 16 to y register 3G.
The decimal data rBFnJ is written, and the flag "1" indicating 0VERRANGE and the maximum coordinate data "63" are written and completed. Furthermore, if NO in step Y5, this Y
The coordinate calculation barrier does not exceed the range, so it ends.

Next, according to the flowchart of FIG. 9, the step G7 is
The calculation of the X coordinate will be explained.

First, in step Xi, the calculation of the formula shown in the figure is executed using the data in the x seo register 3N, the data set in the X5Ln register 3H, and the X++ax register 3I, and the result is set in the X register 3F. .

Next, in step x2, the data in the X register 3F is converted into an integer, and the process then proceeds to step x3, where it is determined whether the data is smaller than "0". So, YES
When this happens, the process advances to step x4, where the same processing as step Y4 is performed, setting the UNDERRANGE flag in the X register 3F, and writing the minimum coordinate data rOJ.

On the other hand, if NO in step x3, the process proceeds to step x5, and it is determined whether the data in the X register 3F is greater than "95." If YES, the process proceeds to step x6, and the flag 0VERRANG'E is set in the X register 3F. and hexadecimal data DFH indicating the maximum coordinate data "95" are written and the process ends.

Further, in step x5, if the data in the X register 3F is smaller than "95", the current X coordinate calculation ends because the range is not over.

Next, the operation of the scale processing in step GIO will be explained using the flowcharts shown in FIGS. 10(1) and 10(2).

First, in step S1, it is determined whether the data in the X5CL register 3L is "0" or not, but in the present example, it is "90" as shown in FIG. 5, so the process proceeds to step S2.
It is determined whether the current X coordinate is less than or equal to "63". Therefore, in the example of Fig. 5, the answer is YES, and the X coordinate is OV E RR.
A N G E 't' t* @ '/' Proceeds to step S4 and determines whether the X coordinate is less than or equal to its center coordinate "32". In the example of FIG. 5 where it is "32", the X coordinate axis is Since it is located below the center of the display section 8, proceed to step S5, add 1 to the X coordinate, and store it in the y register 3G.
Set to . As a result, for the X axis, Figure 6 (B
) or (C), the scale is on the X-axis.

That is, it is attached toward the wider space at the center of the screen.

Next, in step S7, the coordinate data in the X register 3F is saved to the A register 3A, and then the calculation in step S8 (
-180÷90) and set "-2" in the B register 3B. In step S9, the data is rounded, and in step 310, the data "90" in the X SCL register 3L and the data "90" in the B register 3B are rounded.
-2'' and the resulting r-180'' is
Set in se*o register 3N. Then, in step Sll, the X coordinate calculation shown in FIG. 9 is performed. As a result, the X coordinate rOJ is obtained through step x1. Then, in step S12, the above-mentioned X coordinate is rDFH
J or not is determined, and if the answer is No, it is not a calculation error, so the process proceeds to step S14, and the X coordinate is r80++J.
It is determined whether or not, and since the answer is No, the process proceeds to step S15, and the X coordinate point is plotted. And step S1
At step 6, the data in the B register 3B is incremented by 1 to become "-1", and the process returns to step SIO.

Next, in step S10, the x aemo register 3N
The data becomes r-90J. And step 511
Then, the X coordinate becomes r by the calculation in step Xl.
23.75J, converting it into an integer, the X coordinate becomes 2
4". And soo step 512, 514, 51
5 is executed, and then in step 516, the B register,
The data of 3B becomes "O". Next, the process returns to step 510, and the data in the Xae auto register 3N becomes rQJ.Then, by the calculation in step S11, the X coordinate becomes "48", and then in step 512, si4, S1
5. S16 is executed and the data in the B register 3B becomes “1”.
”. Then return to step SIO
The data in register 3N becomes "+90". Then, in the X coordinate calculation in step S11, the X coordinate becomes "71". Next, steps S12, S14. S15 and S16 are executed, and the data in the B register 3B becomes "2". Then, return to step S10, X. The data of 0 register 3N becomes r180J. Then, in the X coordinate calculation in step S11, the X coordinate becomes "95", and in step S11, the
1.2, S14. S15 and S16 are executed, and data "3" is set in the B register 3B. Next, by executing step SIO, the data in the Xsemo register 3N becomes "r270", and then in the X coordinate calculation in step Sll, the is set, and as a result, in step 312, the result is YES, and the process proceeds to step S13, where the data saved in the A register 3A is returned to the X register 3F, and the process proceeds to step S17, where the scale processing for the Y axis begins. That is, with respect to the X-axis, graduations are provided at four locations using the data "90" in the X SCL register 3L.

Next, in step S17, in the present example, the data in Vsc[register 3M is rQ, 5J, which is not 0, so proceeding to step 518, it is determined whether the X coordinate of X register 3F is "95" or less, and In the example in Figure 5, the answer is YES,
Proceeding to step 520, it is checked whether the Y axis is to the right or left of the center of the display section 8. In the example of FIG. 5, it is on the left side, and the X coordinate data of the Y axis is less than "48", so proceed to step S21 and add the X coordinate data of the Y axis to +
Do 1.

As a result, as shown in Figure 6 (A), for the Y axis,
A scale is provided on the right side, that is, towards the wider space at the center of the screen. Thereafter, steps S23 to 530, which are processing steps similar to steps S8 to 516 described above, are repeatedly executed to calculate a scale for the Y coordinate.

On the other hand, if NO is obtained in step S2 above, Y
Since the coordinates exceed the maximum coordinates, step S
Proceed to step 3, data in y register 3G and data r3F+
+J (63) is performed, the upper two bits of the y register 3G are cleared, and the process proceeds to step S7.

Then, steps S7 to S16 are executed to perform scale processing for the X-axis.As a result, as shown in FIG. 6(D), for the X-axis, the outer edge (side) of the display screen of the display unit 8
A scale is placed below the X-axis, that is, toward the center of the screen.

On the other hand, if NO in step S4, step S
6, the data in the y register 3G is decremented by 1, and the process proceeds to step S7.In this case, the X coordinate axis is located above the center of the display section 8, and the As shown in FIG. 6(A), the scale is directed downward, that is, toward the widest direction of the screen space.

Furthermore, if NO is determined in step S18, the X coordinate exceeds its maximum coordinate, so the process proceeds to step S19, where the data in the X register 3F is logically ANDed with the data [5FHJ, and the upper 1 bit is cleared. And below, step S
Execute steps 23 to S30 and perform scale processing for the Y axis.
As a result, the scale for the Y coordinate is placed on the outer edge of the display screen of the display unit 8 toward the center of the screen, as shown in FIG. 6(C).

Furthermore, if the result in step 520 is No, it means that the Y-axis is on the right side of the center of the display section 8, and step S22
As a result, the X coordinate data of the Y axis is decremented by 1, it is set in the X register 3F, and the calculation for attaching a scale to the Y axis in steps S23 to S30 is performed.As a result, as shown in FIG.
As shown in B), with respect to the Y axis, the left side, that is, the display section 8
A scale is placed toward a wide space in the center of the screen.

The display example in Figure 6 (D) is an example in which both of the calculated coordinate axes are outside the display screen area, especially the X-axis coordinate exceeds its maximum coordinate, and the Y-axis coordinate exceeds its minimum coordinate. This shows an example that goes beyond.

Next, according to the flowchart of FIG. 11, the above step Gll
6. That is, in step M1, the first pointer (address "0") of the execution pointer 4 is transferred and saved to the pointer register 3C, and the data "F" is stored in the yo register 3E.
FJ (hexadecimal code) is written and X register 3F is further cleared.

Next, in step M2, the X*in register 3H.

The calculation of the formula shown is executed using the data preset in the X ff1ax register 3 and the data in the X register, which is currently "0", and the data (currently is X sin register 3
The data preset to H is “-180”)
is obtained and set in the X memo register 3N. That is, the coordinates of the first display dot in the X coordinate direction are determined by this.

Next, in step M3, the address rQJ saved in the pointer register 3C is returned to the execution pointer 4, and in the next step M4, this address is changed from "0" to "4".
The functional operation of equation (1) in the equation buffer 7 up to this point is executed, and the first answer is set in the ymemo register 3P. Next, in step M5, it is determined whether the answer is a calculation error or not. If YES, the process proceeds to step M6, where a hexadecimal code rFFJ indicating error data is written in the y register 3G, and then the process proceeds to step M9. .

On the other hand, when the result in step M5 is No, steps M7 and M8 are executed, and the Y coordinate calculation (in this case, the coordinate of the first display dot in the Y coordinate direction) is performed according to the flow shown in FIGS. ) and its (x, y
) is sent to the graph display buffer 6A, and a process of lighting the display dot on the display section 8 is executed. The process then proceeds to step M9.

In step M9, from X register 3F to Xo register 3
The current calculation result data is transferred and saved to D as the previous calculation result data, and the same goes.

The current calculation data is transferred and saved from the y register 3G to the yo register 3E as the previous calculation data.

Next, in step MIO, the data in X register 3F is +1
In addition, in step Mll, it is determined whether the resulting data is greater than "96", which is larger than the maximum display coordinate "95" in the Returning, each coordinate of the second and subsequent (x, y) is executed by repeating steps M2 to Mll, and when YES is obtained in step Mll, the calculation is finished, and as a result, as shown in Fig. 2. A graph shown is displayed on the display unit 8.

Next, the DRAW processing in step M8 will be explained with reference to the flowchart in FIG.

First, in step D1, the upper digits of the yo register 3E (
4b i t) is judged whether it is data "F" indicating out of range, and if YES, this flow ends and the display operation for this coordinate is not executed.On the other hand, N
When the answer is 0, the process proceeds to step D2, where it is determined whether the data in the upper digit of the y register 3G is data "F" indicating outside the range, and when the answer is YES, display of this coordinate point is prohibited. On the other hand, when the answer is NO, the process proceeds to step D3, and each coordinate between (Xo, ``lo'') and (x, y) is calculated according to the data set in the XO register 3E, Yo register 3F, X register 3F, and V register 3G, respectively. A graph display operation for connecting the points is executed and ends.In the above embodiment, scales are attached only to one side of the X-axis and Y-axis, but they may be attached to both sides.

[Effects of the Invention] As explained above, the present invention is a calculator that calculates and displays a graph of a function, and which calculates and displays the position of coordinate axes (X-axis, Y-axis) according to a preset variable range. Since this is a small electronic calculator equipped with a graph display function that calculates the scale position and displays the coordinate axes and scale on the graph display section, it has the advantage that the displayed graph is very easy to see.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of an embodiment of the present invention, FIG. 2 is a diagram showing a graph obtained by calculating an input function formula, and FIG. 3 is a diagram showing the relationship between the above function formula and the execution pointer 4. figure,
Figure 4 is a data configuration diagram of XO register 3D to y register 3G, etc., Figure 5 is a diagram of a display example of range data and scale data input manually, Figure 6 is a diagram of a display example of coordinate axes and scales, and Figure 7 is a diagram of a display example of coordinate axes and scales. 12 through 12 are flowcharts for displaying graphs, coordinate axes, and scales. 1A...Numeric keypad, IB...Function key, IC...Function key, ID...
・・Graph key, IE・・Range key, IF・
...EXE C execution) key, 2...Control unit, 3C...Pointer register, 3D...
...Xo register, 3E...Vo register, 3F...X register, 3G...y register, 3H...X5ln register, 3I...
...X wax register, 3J...3
' sin register, 3K...7 wax
Register, 3L...X S CL register,
3M..."! SCL register, 3N...
...Xme■register, 3F...V *es
o register, 4...execution pointer, 5...
...Arithmetic unit, 6A...Graph display buffer, 7
...Formula buffer, 8...Display section. Patent applicant Casio Computer Co., Ltd. Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 8 Figure 9

Claims (1)

[Claims] A small electronic calculator equipped with the function of displaying graphs on a matrix type display section, which includes an input means for inputting a function formula and range data indicating the range of each variable included in the function formula input by this input means. a range input means for inputting; a range data storage means for storing the range data;
The graph display data of the function formula is calculated from the range data of each of the variables and the function formula, and the positions of the coordinate axes and scale positions with respect to the display graph are calculated according to the range data, and together with the graph, the matrix type 1. A small electronic calculator with a graph display function, characterized by comprising means for automatically displaying the information on a display section.