JP2020042767A - Calculator, calculation method, and program - Google Patents

Abstract

To provide a calculator, a calculation method, and a program that can switch between a numerical value associated with tax calculation and a numerical value associated with ordinary calculation to display it on a display.SOLUTION: A calculator comprises a control section configured to: perform first calculation using a numerical value according to an input of an execution instruction of first calculation; store a first numerical value associated with a result of the performed first calculation in a first memory and display it on a display; perform second calculation using a numerical value according to an input of an execution instruction of second calculation different from the first calculation; store a second numerical value associated with a result of the performed second calculation in a second memory and display it on the display; display the first numerical value stored in the first memory on the display when inputting of a first reading instruction is performed while the numerical value indicating the result of the performed first calculation is displayed on the display; and display the second numerical value stored in the second memory on the display when inputting of the first reading instruction is performed while the numerical value indicating the result of the performed second calculation is displayed on the display.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a calculator for calculating tax, a calculation method, and a program.

  In recent years, some tax calculators (calculators) have a function of calculating a tax using a preset tax rate. For example, the calculator described in Patent Literature 1 performs arbitrary four arithmetic calculations, and operates a tax-inclusive key (confirmation key) while displaying a numerical value (amount) to be multiplied. A tax-inclusive amount based on the first tax rate is calculated and displayed. Similarly, when the tax-inclusive key (confirmation key) is operated again, a tax-inclusive amount based on the second tax rate is calculated and displayed on the displayed numerical value.

  In addition, the tax calculator described in the cited reference 2 has a plurality of tax calculation keys (calculation key including tax, calculation key without tax) respectively corresponding to a plurality of tax rates, and a dedicated key (calculation key including tax). Tax calculation total key) is provided. The tax calculator calculates the tax-inclusive amount at the tax rate corresponding to each tax calculation key based on the numerical value calculated normally by any four arithmetic calculations or the numerical value entered individually according to the operation on each tax calculation key. Calculate and display. Furthermore, a total sum of tax included amounts calculated based on each of the plurality of tax rates is calculated and displayed.

JP-A-10-143472 JP 2017-174225 A

  Conventionally, by operating the same key as a key for displaying a first numerical value (for example, a total sum of tax calculations) relating to the result of a first calculation (for example, tax calculation, etc.), a second calculation (for example, different from the first calculation) There is no known display of a second numerical value (for example, a total sum of normal calculations) relating to the result of the normal calculation. When a key for displaying the first numerical value and a key for displaying the second numerical value are separately provided in the key input unit, the space for the two keys is occupied.

  The present invention has been made in consideration of the above problems, and has a calculator, a calculation method, and a calculator that can display a numerical value related to a first calculation and a numerical value related to a second calculation on a display unit based on the same operation. And to provide programs.

  In order to solve the above problem, a computer according to the present invention executes a first calculation using a numerical value in response to an input of an instruction to execute a first calculation, and performs a first calculation relating to a result of the executed first calculation. The numerical value is stored in the first memory and displayed on the display unit, and the second calculation using the numerical value is executed in response to the input of the execution instruction of the second calculation different from the first calculation. (2) storing a second numerical value related to the result of the calculation in the second memory and displaying the second numerical value on the display unit, and displaying a numerical value indicating the result of the first calculation executed on the display unit, the first readout instruction; When the input of is performed, the first numerical value stored in the first memory is displayed on the display unit, and the numerical value indicating the result of the executed second calculation is displayed on the display unit. When the first read instruction is input, the data is stored in the second memory. The second numerical value to be displayed on the display unit, and a control unit.

  According to the present invention, the numerical value related to the first calculation and the numerical value related to the second calculation can be displayed on the display unit based on the same operation.

The front view showing the appearance composition of the tax calculator in this embodiment. FIG. 2 is a block diagram showing a configuration of an electronic circuit of the calculator according to the embodiment. 6 is a flowchart for explaining the operation of a tax calculation function of the calculator according to the embodiment. 6 is a flowchart for explaining the operation of a tax calculation function of the calculator according to the embodiment. 6 is a flowchart for explaining the operation of a tax calculation function of the calculator according to the embodiment. 6 is a flowchart for explaining the operation of a tax calculation function of the calculator according to the embodiment. 6 is a flowchart for explaining the operation of a tax calculation function of the calculator according to the embodiment. FIG. 4 is a view showing a specific example of an input operation and a display for explaining a tax calculation function of the calculator according to the embodiment. FIG. 4 is a view showing a specific example of an input operation and a display for explaining a tax calculation function of the calculator according to the embodiment. FIG. 4 is a view showing a specific example of an input operation and a display for explaining a tax calculation function of the calculator according to the embodiment. FIG. 4 is a view showing a specific example of an input operation and a display for explaining a tax calculation function of the calculator according to the embodiment. The figure which shows an example of the slip format used in the Indian retail store.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a front view showing an external configuration of the tax calculator according to the present embodiment. In the present embodiment, the tax calculator is realized as a calculator 10 dedicated to calculation.

  In addition, the tax calculator is configured as the calculator 10, and has a calculation function (a calculation processing program is mounted), such as a personal computer, a tablet computer, a smartphone, a mobile phone, a touch panel PDA (personal digital assistants), an electronic book, It can be configured as a portable game machine or the like. It should be noted that a tax calculator with no physical keys (buttons) such as the calculator 10 displays a software keyboard similar to the keys of the calculator 10 and executes calculation processing in accordance with key operations on the software keyboard. .

  The calculator 10 according to the present embodiment is provided with a tax calculation function for calculating a tax at a plurality of tax rates, for example, at five different tax rates. For example, in India, five kinds of tax rates (0%, 5%, 12%, 18%, and 28%) are used as consumption tax. Therefore, the calculator 10 according to the present embodiment is suitable for tax calculation for calculating the total amount of a product in which a plurality of types of consumption tax of five or less are mixed in India and the like.

  A key input unit 11 including a plurality of keys, a display unit 12, and a solar panel 13 are provided on the front of the housing of the calculator 10. The key input unit 11 is provided with numerical keys, calculation keys, tax calculation function keys, function keys, and check function keys. The numerical keys include, for example, a plurality of keys corresponding to [00] [0] to [9]. The operation keys include, for example, a [+] (addition) key 11h1, a [-] (subtraction) key 11h2, a [x] (multiplication) key 11h3, and a [算] (division) key 11h4, which are used for normal calculations by four arithmetic operations. , [=] (Calculation execution) key 11h0.

  The tax calculation function keys include a tax calculation key ([GST + n (TAX-n)]) 11b, a tax calculation total key ([GST GT (GT)]) 11c, and a tax calculation mode switching key ([GST + / TAX-]). 11d is provided. Here, GST is an abbreviation for “Goods and Service Tax” which means Indian consumption tax. The character string in [] (however, the character string in () is excluded) indicates the character string printed on the key top of each tax calculation key 11 b, and further in () in []. Is a character string printed on the front of the housing of the calculator 10 for the sake of convenience. In this specification, not only the tax calculation key 11b but also the same notation is used.

  The tax calculation key ([GST + n (TAX-n)]) 11b includes a tax 0 calculation key ([GST + 0 (TAX-0)]) 11b0, a tax 1 calculation key ([GST + 1 (TAX-1)]) 11b1, and a tax 2 calculation keys ([GST + 2 (TAX-2)]) 11b2, tax 3 calculation keys ([GST + 3 (TAX-3)]) 11b3, and tax 4 calculation keys ([GST + 4 (TAX-4)]) 11b4. The tax 0 calculation key ([GST + 0 (TAX-0)]) 11b0 is operated to input a tax calculation execution instruction using the tax rate 0. Similarly, a tax 1 calculation key ([GST + 1 (TAX-1)]) 11b1, a tax 2 calculation key ([GST + 2 (TAX-2)]) 11b2, and a tax 3 calculation key ([GST + 3 (TAX-3)]) 11b3 and a tax 4 calculation key ([GST + 4 (TAX-4)]) 11b4 are operated to input a tax calculation execution instruction using the tax rate 1, the tax rate 2, the tax rate 3, and the tax rate 4, respectively. In this specification, as described above, when the tax calculation key ([GST + n (TAX-n)]) 11b is used, “n” is used instead of each numerical value from 0 to 4. In the present specification, not only the tax calculation key 11b but also a specific numerical value when there is no particular limitation on which numerical value (an integer from 0 to 4) can be taken by “n”. This will be described for convenience using “n” instead of “n”.

  One tax calculation key 11b (tax n calculation keys 11b0 to 11b4) also serves as a tax-inclusive calculation key [GST + n] and a tax-exempt calculation key [TAX-n]. The tax calculation key 11b (tax n calculation key 11b0 to 11b4) is a tax-inclusive calculation key [GST + n] or a tax-inclusive calculation key [GST + n] according to the tax calculation mode switched in response to the operation of the tax calculation mode switching key ([GST + / TAX-]) 11d. Used as a tax-excluding calculation key [TAX-n]. By sharing one tax calculation key 11b as a tax-inclusive calculation key [GST + n] and a tax-exclusive calculation key [TAX-n], a limited area of the front surface of the housing is effectively used, and a plurality of (five types) are used. A key is provided that can execute a tax-inclusive calculation process and a tax-excluding calculation process corresponding to each tax rate.

  The tax rates (tax rates 0 to 4) assigned to the tax calculation keys 11b (tax n calculation keys 11b0 to 11b4) are preset when the calculator 10 is shipped from the factory. For example, five tax rates (0%, 5%, 12%, 18%, and 28%) are set in the tax n calculation keys 11b0 to 11b4, respectively, in accordance with use in India. The tax rates (tax rates 0 to 4) assigned to the tax n calculation keys 11b0 to 11b4 can be arbitrarily set by a user operation.

  The tax calculation total key ([GST GT (GT)]) 11c includes a grand total key ([GT] key) for displaying a grand total for normal calculations (basic calculations) such as four arithmetic calculations and constant calculations, and a tax calculation key. Also serves as a GST grand total key ([GST GT] key) for displaying the total sum for the calculation result of. When the tax calculation total key 11c functions as a GST grand total key, the tax calculation is performed and the processing mode of the calculator 10 transits to the tax total recall mode (GST GT recall mode). On the other hand, when the tax calculation total key 11c functions as a grand total key, the processing mode of the calculator 10 does not particularly change, and the numerical value stored in the total memory area 22h is simply called and displayed on the display unit 12. Is done. These processes will be described later in detail with reference to FIG.

  The tax calculation total key 11c functions as either a grand total key ([GT] key) or a GST grand total key ([GST GT] key) depending on the operation state immediately before the tax calculation total key 11c is operated. I do. Specifically, when the processing mode of the calculator 10 is not the tax total recall mode, for example, immediately after the tax calculation is performed by operating the tax calculation key 11b, that is, after the tax calculation is performed, When the tax calculation total key 11c is pressed while the result is displayed on the display unit 12, the tax calculation key 11b is used as a GST grand total key ([GST GT] key) for displaying a total sum of the calculation results of the tax calculation. ). Further, when the processing mode of the calculator 10 is not the tax total recall mode, for example, immediately after the normal calculation is performed by operating the calculation execution key ([=] key) 11h0, that is, after the normal calculation is performed, If the tax calculation total key 11c is pressed while the result of the normal calculation is displayed on the display unit 12, that is, if the tax calculation is not performed immediately after the tax calculation key 11b is operated, the tax calculation key 11b is , Functions as a grand total key ([GT] key) for displaying a total sum for a normal calculation (basic calculation). Here, the pressing time of the tax calculation total key 11c is shorter than an arbitrary predetermined time, and is shorter than the "long press" described below. Also, pressing for a short time is referred to as “short pressing” or a normal pressing operation in this specification.

  Further, the tax calculation total key 11c functions as a key opposite to the above when an operation (for example, long press) different from a normal press operation is performed. That is, for example, when the tax calculation total key 11c is long-pressed immediately after the tax calculation is performed by operating the tax calculation key 11b, the tax calculation total key 11c is used as a grand total key ([GT] key). Function. Further, for example, when the tax calculation total key 11c is long-pressed immediately after the normal calculation is performed by operating the calculation execution key ([=] key) 11h0, that is, the tax calculation is performed by operating the tax calculation key 11b. If not, the tax calculation total key 11c functions as a GST grand total key ([GST GT] key). The operation different from the normal operation for the tax calculation total key 11c may be another operation other than the above-mentioned long-pressing operation (the operation of keeping the pressed state for a predetermined time or more). It is.

  The function keys include, for example, an all clear key ([AC] key 11a), a clear key ([C] key), a plurality of memory keys ([MRC] [M-] [M +]), and a root key ([√] key). ), [%] Key 11g and the like. The [%] key 11g is used not only for calculating the percentage, but also for setting a tax rate corresponding to each of the tax calculation keys 11b (tax n calculation keys 11b0 to 11b4) to a value input by key operation. Used to initiate the configuration process.

  The check function key is a key used in the check function for confirming / correcting the contents of the calculation executed earlier. The verification function keys include a confirmation key ([CHECK BACK] key 11e, [CHECK FWARD] key 11f) and a correction key ([CORRECT] key) 11k. [CHECK BACK] key 11e and [CHECK FWARD] key 11f are keys for switching and displaying the contents (calculation data) of the previously executed calculation in units of steps. When the [CHECK BACK] key 11e is operated, the display is switched to the calculation data of the step in the direction in which the number of steps is small, and when the [CHECK FWARD] key 11f is operated, the calculation data in the direction in which the number of steps is large is displayed. Switch the display. In addition, one step is a unit of “numeric value + function” input for calculation. In the “function”, a code of a key operated for four arithmetic calculations, tax-inclusive calculations, tax-excluding calculations, and the like is stored. The correction key 11k is a key for instructing the correction of the content of the calculation (“the number input + function”) displayed by operating the [CHECK BACK] key 11e or the [CHECK FWARD] key 11f. By inputting the content of the corrected calculation after operating the correction key 11k, the displayed previously input calculation data can be corrected.

  The round selector 11y sets a calculation method of the fraction processing. For example, the “F” setting specifies the display of the maximum displayable digit including the decimal part on the display unit 12. The “CUT” setting specifies the truncation of the digit specified by the decimal point selector 11z. The “UP” setting specifies rounding of the digit specified by the decimal point selector 11z. The “5/4” setting specifies the rounding of the digit specified by the decimal point selector 11z. The decimal point selector 11z sets how many digits after the decimal point are displayed on the display unit 12. The “ADD2” setting specifies the decimal point setting to a predetermined number of digits for the input numerical value.

  The display unit 12 includes a dot matrix type liquid crystal display unit. The display unit 12 displays numerical values input by operating the keys of the key input unit 11. The display unit 12 displays numerical values for a limited number of lines (for example, one line). Characters and symbols (symbols) indicating the calculation mode being set and various setting states are displayed in a state display area provided along the side of the display unit 12. For example, in the status display area, the number of steps 12a, the tax calculation mode symbol 12b, the tax calculation key symbol 12c, the tax total recall mode symbol 12d, the total sum display symbol 12e, the memory symbol 12f, and the like are displayed. In FIG. 1, all displayable symbols are shown on the same screen for the sake of convenience in describing the status display area. However, in an arbitrary state that the calculator 10 can take, such a large number of symbols are the same. They are not always displayed on the screen at the same time.

  The step number 12a indicates the position of the current step to be displayed, with “numerical value + function” input by operating the key of the key input unit 11 as one step. The tax calculation mode symbol 12b indicates the current tax calculation mode. For example, [GST +] is displayed in the tax-inclusive calculation mode for executing the tax-inclusive calculation, and is displayed in the tax-exclusive calculation mode for executing the tax-independent calculation. Displays [TAX-], for example.

  The tax calculation key symbol 12c is a symbol indicating the tax rate used for the tax calculation and either the tax-inclusive calculation or the tax-excluding calculation when the tax calculation is performed by operating the tax calculation key 11b. When the tax calculation key 11b is used as the tax included calculation key [GST + n], any one of [GST + 0], [GST + 1], [GST + 2], [GST + 3], and [GST + 4] corresponding to each of the tax rates 0 to 4 is displayed. Is done. When the tax calculation key 11b is used as the tax-excluded calculation key [TAX-n], [TAX-0], [TAX-1], [TAX-2], [TAX-2] corresponding to the tax rates 0 to 4, respectively. TAX-3] or [TAX-4] is displayed.

  The tax total recall mode symbol 12d is a symbol indicating that a transition has been made to the tax total recall mode (GST GT recall mode) by operation of the tax calculation total key ([GST GT (GT)]) 11c, for example, "RCL" is displayed. Is displayed. In the tax total recall mode, a total sum of tax calculations calculated at each tax rate (tax rates 0 to 4) is calculated in accordance with a key operation on the tax calculation total key 11c. The amount can be switched and displayed. In the tax total recall mode, a tax rate to be displayed (tax rates 0 to 4) is specified by a key operation on the tax calculation key 11b. The amount and the total tax amount can be switched and displayed.

  The total display symbol 12e is a symbol indicating that the calculation result of the normal calculation performed in response to the operation of the calculation execution key [=] 11h0 is stored in the total memory area 22h. For example, "GT" is displayed. You. The memory symbol 12f is a symbol indicating that a numerical value is stored by a memory function in response to an operation of a memory key ([M-] [M +]).

  The solar panel 13 generates electric power when the illuminance of ambient light when the calculator 10 is used is bright to some extent. The solar panel 13 functions as a power supply unit 26 (shown in FIG. 2) of the calculator 10 during power generation, and supplies power to each unit of the calculator 10. When the solar panel 13 is not generating power, power is supplied to each unit of the calculator 10 from a primary battery as a power supply unit 26 separately provided in the calculator 10.

  FIG. 2 is a block diagram illustrating a configuration of an electronic circuit of the calculator 10 according to the present embodiment. The electronic circuit of the calculator 10 includes a plurality of units constituting a computer including a CPU 21.

  The CPU 21 controls the operation of each part of the circuit by executing the calculation processing program 22a stored in the memory 22. When an input operation is performed on the key input unit 11, the CPU 21 detects a key on which an input operation has been performed based on a key input signal from the key input unit 11, and executes various calculation processes according to the detected keys. I do. In the calculator 10, the CPU 21 controls the operation of each part of the circuit according to the instructions described in the calculation processing program 22a, and the software and the hardware operate in cooperation to execute the processing by the calculation function described in the following operation description. Implement calculation processing including:

  The calculation processing program 22a may be stored in the memory 22 in advance, may be read from an external recording medium 23 such as a memory card via a recording medium reading unit 24, or may be communicated via a communication unit 25. It may be downloaded from the server 30 on the network N (including the Internet or the like).

  In addition to the calculation processing program 22a, the memory 22 stores an area (tax memory) for storing the calculation result of the tax calculation, a total memory area 22h, a total tax recall mode area 22k, a tax calculation mode area 22m, and a buffer memory. An area for storing each data, such as an area 22n, a display memory area 22p, and a tax rate storage area 22r, is provided. The tax memory (first memory) includes a tax rate 0 total memory area 22b, a tax rate 1 total memory area 22c, a tax rate 2 total memory area 22d, a tax rate 3 total memory area 22e, a tax rate 4 total memory area 22f, and a tax total memory area 22g. Is included. In the following description, the tax rate 0 total memory area 22b, the tax rate 1 total memory area 22c, the tax rate 2 total memory area 22d, the tax rate 3 total memory area 22e, and the tax rate 4 total memory area 22f are collectively referred to as tax totals by tax rate. It may be described as memory areas 22b to 22f.

  The tax rate 0 total memory area 22b is an area for storing data calculated by a tax calculation based on the tax rate 0. In the tax rate 0 total memory area 22b, a numerical value based on the result of the tax-inclusive calculation of the tax rate 0 is stored. Specifically, the tax amount (the 0th tax amount), the tax amount (the 0th tax amount), and the tax amount as a result of the tax-inclusive calculation of the tax rate 0 performed at least once after the input operation of the [AC] key 11a, The total amount of the tax-excluded amount (the 0th tax-excluded amount) is stored as the 0th tax-included total amount, the 0th tax-excluded total amount, and the 0th tax total amount, respectively.

  The tax rate 1 total memory area 22c, the tax rate 2 total memory area 22d, the tax rate 3 total memory area 22e, and the tax rate 4 total memory area 22f are based on the respective tax rates 1 to 4 in the same manner as the tax rate 0 total memory area 22b. This is an area for storing data calculated by the tax calculation. Detailed description is omitted.

  The tax total memory area 22g is an area for storing data indicating a total of numerical values calculated by tax calculations based on all tax rates 0 to 4. In the tax total memory area 22g, the total tax-included total amount including the 0 to 4th tax-inclusive total amount, the total tax-excluded total amount corresponding to the tax-included total total amount, and the tax-inclusive amount are provided in accordance with the input operation of the tax calculation total key 11c. The total tax amount corresponding to the total amount is stored.

  The total memory area 22h is an area for storing data indicating a total of numerical values calculated by the normal calculation (second memory). In the total memory area 22h, the calculation result of the normal calculation is calculated according to the operation of the calculation execution key [=] 11h0, and the numerical value as the calculation result is added to the numerical value stored in the total memory area 22h. .

  In the total tax recall mode area 22k, a total tax recall mode flag indicating whether or not the user is in a recall mode in accordance with an input operation on the total tax calculation key 11c is set to an ON state or an OFF state. The tax total recall mode is turned on when the tax calculation total key 11c is pressed immediately after the tax calculation by operating the tax calculation key 11b, or when the tax calculation total key 11c is pressed and held immediately after the normal calculation. (Transition to tax total recall mode). The tax total recall mode is turned off when, for example, the [AC] key 11a is operated as a predetermined instruction for turning off the tax total recall mode. The switching of the tax total recall mode on / off is not limited to the operation of the tax calculation total key 11c and the [AC] key 11a. For example, on / off of the tax total recall mode may be switched according to another key operation or the processing result of the calculator 10.

  When the total tax recall mode is on, every time the total tax calculation key 11c is operated (pressed), the total total including tax, the total total before tax, and the total total tax are stored in the total tax memory area 22g. The amount can be switched and displayed. When the tax total recall mode is in the ON state, each time the tax calculation key 11b (the tax n calculation keys 11b0 to 11b4) is operated (pressed), the tax total is stored in the tax total memory areas 22b to 22f for each tax rate. , The total amount including tax, the total amount without tax, and the total amount of tax can be switched and displayed.

  The ON state of the tax total recall mode is maintained even when the numerical keys and the calculation keys of the key input unit 11 are input. Therefore, the normal calculation using the numerical keys and the operation keys can be executed while displaying and confirming the result of the tax calculation by the input operation of the tax calculation total key 11c or the tax calculation key 11b (11b0 to 11b4). In the normal calculation in the ON state of the total tax recall mode, a numerical value as a result of the tax calculation is displayed on the display unit 12, and four arithmetic calculations can be executed on the number displayed on the display unit 12. .

  The tax calculation mode area 22m stores tax calculation mode data that is switched according to an input operation on the tax calculation mode switching key 11d and that indicates the state of the tax included calculation mode or the tax excluded calculation mode.

  The buffer memory area 22n stores the numbers entered so as to form a unit in combination with the last input function. The display memory area 22p stores the numerical value displayed on the display unit 12 at that time. For example, when the numerical value “100” is operated as a numerical value by operating a numerical key and the tax 1 calculation key ([GST + 1 (TAX-1)]) 11b1 is sequentially operated as a function, the numerical value is stored in the buffer memory area 22n as the numerical value. Is stored in the display memory area 22p, and the numerical value “105” also displayed on the display unit 12 as a result of the tax-inclusive calculation of the tax rate 1 is stored (however, the tax rate 1 is 5%). if you did this). As described above, the numerical values stored in the buffer memory area 22n and the display memory area 22p are sequentially overwritten and updated according to the latest input operation.

  The tax rate storage area 22r stores numerical values indicating the tax rates 0 to 4 set for the tax calculation keys 11b (tax n calculation keys 11b0 to 11b4). For example, five tax rates (0%, 5%, 12%, 18%, and 28%) are set in the tax n calculation keys 11b0 to 11b4 at the time of shipment from the factory in accordance with use in India. In this case, the tax rate storage area 22e stores "0", "5", "12", "18", and "28" for each of the tax rates 0 to 4 corresponding to the tax n calculation keys 11b0 to 11b4. The numerical value is stored.

  Next, the operation of the calculator 10 in the present embodiment will be described. FIGS. 3, 4, 5, 6, and 7 are flowcharts for explaining the operation of the tax calculation function of the calculator 10 in the present embodiment. FIGS. 8, 9, 10 and 11 are diagrams showing specific examples of input operations and displays for explaining the tax calculation function of the calculator 10 in the present embodiment.

  In the following description, the tax rate 1 corresponding to the tax 1 calculation key ([GST + 1 (TAX-1)]) 11b1 will be set to 5% for convenience.

  First, the user operates (presses) the [AC] key 11a in order to clear the display and the contents of the memory before starting the calculation. When the [AC] key 11a is operated (Step A9: Yes), the CPU 21 stores the tax total memory areas 22b to 22f by tax rate, the tax total memory area 22g, the total memory area 22h, the buffer memory area 22n, and the display in the memory 22. The entire memory area 22p is cleared (step A12). Further, the CPU 21 turns off the tax total recall mode flag stored in the tax total recall mode area 22k (step A13). When the [AC] key 11a is operated in a state where the numerical value such as the tax calculation result is displayed, the CPU 21 clears the previously displayed numerical value and displays “0”. When the [AC] key 11a is operated in a state where the previous symbol is displayed in the status display area of the display unit 12, the CPU 21 clears the previously displayed symbol and hides it.

  If an input operation on the tax calculation key 11b (any of the tax n calculation keys 11b0 to 11b4) is detected immediately after the input operation of the [AC] key 11a (step A19: Yes), A117: Yes, the CPU 21 The tax rate set for any of the tax n calculation keys 11b0 to 11b4 for which the input operation has been performed is read from the tax rate storage area 22r of the memory 22 and displayed on the display unit 12 (step A118). For example, when the tax 1 calculation key 11b1 is operated immediately after the input operation of the [AC] key 11a, the CPU 21 stores the numerical value indicating the tax rate 1 (5%) set in the tax 1 calculation key 11b1 in the tax rate storage area. Read out from 22r and display “5” on the display unit 12.

  Here, when an input operation on the tax calculation key 11b (any one of the tax n calculation keys 11b0 to 11b4) is detected without performing any key operation other than the tax calculation key 11b (step A19: Yes, A117: Yes), that is, as long as the key operation of the tax calculation key 11b continues, the CPU 21 sets any one of the tax rates 0 to 4 set for the input tax calculation key 11b in the same manner as described above. The data is read from the memory 22 and displayed on the display unit 12 (step A118).

  That is, immediately after the input operation of the [AC] key 11a, one of the tax calculation keys 11b (the tax n calculation keys 11b0 to 11b4) is continuously operated, so that each of the tax calculation keys 11b is operated. The set tax rates 0 to 4 can be continuously switched and displayed. After the last input operation of the [AC] key 11a, if only the input operation of the tax calculation key 11b is performed twice or more consecutively, the input operation of the tax calculation key 11b after the second time is performed. Strictly speaking, it is not performed immediately after the input operation of the [AC] key 11a, but in the present specification, such an input operation is also performed immediately after the input operation of the [AC] key 11a. Consider Further, after the last input operation of the [AC] key 11a, if an input operation other than the tax calculation key 11b is performed even once, the input operation of the tax calculation key 11b performed thereafter will be the [AC] key. It is assumed that the operation is not performed immediately after the input operation of 11a.

  Next, when a numerical key is operated by the user to input a numerical value to be calculated (step A10: Yes), the CPU 21 inputs a numerical value (numerical code) corresponding to the input numerical key. The input numerical value is stored in the display memory area 22p and displayed on the display unit 12 (step A15).

  Subsequently, when the operation key is operated (Step A11: Yes), the CPU 21 inputs an operation (operation code) corresponding to the operated operation key, and changes the operation (symbol) symbol of the input operation. It is displayed in the status display area of the display unit 12 (step A16).

  Further, the CPU 21 performs an operation based on the input operation code and the input numerical code, stores the numerical value of the result of the operation in the display memory area 22p, and causes the display unit 12 to display the numerical value. Hereinafter, similarly, by repeatedly inputting the numerical code and the operation code, the CPU 21 sequentially stores the input numerical code and the operation code. Then, when the operation execution key “=” (equal) 11h0 is operated by a user operation (step A17: Yes), the CPU 21 calculates an operation code corresponding to the input operation execution key (“=” key) 11h0. The calculation is performed in accordance with the input numerical code and the operation code, and the numerical value of the calculation result is stored in the display memory area 22p and displayed on the display unit 12. Further, the CPU 21 stores a numerical value as a result of the normal calculation according to the numerical code and the operation code in the total memory area 22h (Step A18). When a numerical value has already been stored in the total memory area 22h, the CPU 21 adds a numerical value obtained as a result of the normal calculation to the previously stored numerical value and stores the result in the memory 22. When the calculation execution key “=” (equal) 11h0 is not operated by the user operation (step A17: No), the CPU 21 returns to the standby state of the input operation.

  If the input operation of the tax calculation key 11b is detected in a state where the numerical value is displayed on the display unit 12 other than immediately after the input operation of the [AC] key 11a (step A19: Yes → A117: No), the CPU 21 With respect to the numerical value (numeric value) displayed on the display unit 12, that is, the numerical value stored in the display memory area 22p, the tax rate set in any of the tax n calculation keys 11b0 to 11b4 for which the input operation has been performed. Perform tax calculation using. It should be noted that the numerical value to be calculated is not limited to the numerical value displayed by the normal calculation, but may be a numerical value input simply by inputting a numerical key.

  The tax calculation key 11b (each of the tax n calculation keys 11b0 to 11b4) serves both as a key for executing a tax-inclusive calculation and a key for executing a tax-excluded calculation. When the tax calculation key 11b is operated, the CPU 21 refers to the tax calculation mode area 22m to determine whether the current tax calculation mode is the tax-inclusive calculation mode or the tax-excluding calculation mode. Here, when the current tax calculation mode is the tax-inclusive calculation mode (step A110, including tax), the CPU 21 executes the tax-inclusive calculation, and performs a tax-inclusive calculation process of displaying the result of the tax calculation in accordance with a key operation. (Step A111). If the current tax calculation mode is the tax-excluded calculation mode (step A110, tax-excluded), the CPU 21 executes the tax-excluded calculation and displays the result of the tax calculation in accordance with a key operation. Is executed (step A112).

  The tax calculation mode is switched by operating the tax calculation mode switching key 11d. When detecting the operation of the tax calculation mode switching key 11d (step A14: Yes), the CPU 21 refers to the tax calculation mode area 22m to determine whether the current tax calculation mode is the tax-inclusive calculation mode or the tax-excluding calculation mode. Determine if there is.

  Here, when the current tax calculation mode is the tax-inclusive calculation mode (step A113, including tax), the CPU 21 stores the tax calculation mode data indicating the tax-excluding calculation mode in the tax calculation mode area 22m (step A114). Further, the CPU 21 displays the tax calculation mode symbol 12b ([TAX-]) indicating the tax-excluding calculation mode in the status display area of the display unit 12 (step A116).

  On the other hand, when the current tax calculation mode is the tax-excluding calculation mode (step A113, excluding tax), the CPU 21 stores the tax calculation mode data indicating the tax-inclusive calculation mode in the tax calculation mode area 22m (step A115). Further, the CPU 21 displays the tax calculation mode symbol 12b ([GST +]) indicating the tax-inclusive calculation mode in the status display area of the display unit 12 (step A116).

  When switching the tax calculation mode in accordance with the operation of the tax calculation mode switching key 11d, the CPU 21 calculates the calculation results (total tax-excluded amount, total tax-included amount, total tax amount) stored in the tax-specific tax total memory areas 22b to 22f. ) As it is. Therefore, when the tax-inclusive calculation and the tax-exclusive calculation are performed in a mixed manner, the calculation result in the middle of the calculation is retained even if the tax calculation mode is switched.

  Next, the tax-inclusive calculation processing in the present embodiment will be described with reference to the flowchart shown in FIG.

  When the tax 0 calculation key 11b0 is operated (step B1: Yes), the CPU 21 executes a tax rate 0 calculation process using the tax rate 0 set for the tax 0 calculation key 11b0 (step B6). Similarly, when the tax 1 calculation key 11b1 is operated (step B2: Yes), the CPU 21 executes a tax rate 1 calculation process (step B10), and when the tax 2 calculation key 11b2 is operated, (Step B3: Yes), the tax rate 2 calculation processing is executed (Step B3). When the tax 3 calculation key 11b3 is operated (Step B4: Yes), the tax rate 3 calculation processing is executed (Step B8). When the tax 4 calculation key 11b4 is operated (step B5: Yes), a tax rate 4 calculation process is executed (step B9).

  The tax rate 0 calculation processing, the tax rate 1 calculation processing, the tax rate 2 calculation processing, the tax rate 3 calculation processing, and the tax rate 4 calculation processing basically execute the same processing. Here, the tax rate 1 calculation process will be described, and detailed description of other calculation processes will be omitted.

FIG. 6 is a flowchart for explaining the tax rate 1 calculation process of the tax-inclusive calculation process in the present embodiment.
When detecting the input operation of the tax 1 calculation key 11b1 (step B2: Yes), the CPU 21 determines whether the tax total recall mode is off or not by referring to the tax total recall mode area 22k. The tax total recall mode is turned on by operating the tax calculation total key 11c. The transition of the tax total recall mode to the ON state is executed in step A28 described later.

  Here, when the tax total recall mode is in the off state (step B21: Yes), the CPU 21 reads the numerical value (numeric value) stored in the display memory area 22p, and sets the read numerical value as the tax-excluded amount. The tax-inclusive amount and the tax amount are calculated based on the tax-excluded amount and the tax rate 1 (“5%”) which is the tax rate according to the tax calculation key 11b on which the input operation is performed, and the calculated tax-inclusive amount and tax amount are calculated. Is stored in the tax rate 1 total memory area 22c (step B22). Further, the CPU 21 stores the numerical value used for the tax-inclusive calculation stored in the display memory area 22p in the buffer memory area 22n, and stores the numerical value of the tax-inclusive amount calculated based on the tax rate 1 in the display memory area 22p. (Step B23). Further, the CPU 21 causes the display unit 12 to display the tax-inclusive amount calculated based on the tax rate 1 (step B24).

  If the step B22 has been executed one or more times before the step B22 is executed this time after the last input operation of the [AC] key 11a, the previously executed one or more times is executed. The tax-excluded amount or the total amount, the tax-inclusive amount or the total amount, the tax amount or the total amount calculated in step B22 are already stored in the tax rate 1 total memory area 22c before executing step B22 this time. Will be. Therefore, when the step B22 is executed, if the tax-excluded amount or the total amount, the tax-inclusive amount or the total amount, the tax amount or the total amount are already stored in the tax rate 1 total memory area 22c, the tax-exclusive amount or the total amount is stored. Add the tax-excluded amount, tax-inclusive amount, and tax amount calculated when step B22 is executed this time to the tax-excluded amount or the total amount, the tax-inclusive amount or the total amount, and the tax amount or the total amount, respectively. . As described above, in the tax rate 1 total memory area 22c, the tax exemption obtained by one or more tax inclusive calculations of all tax rates 1 (step B22) executed after the last input operation of the [AC] key 11a. The sum of the amount, the tax-inclusive amount, and the tax amount is stored.

  In this way, the CPU 21 can continuously instruct the tax-inclusive calculation for a plurality of numerical values (numbers) according to the input operation on the tax 1 calculation key 11b1.

  In the state where the tax-included amount is displayed, the display of the tax-inclusive amount, the tax-excluded amount, and the tax amount can be switched by continuously operating the tax 1 calculation key 11b1 operated to instruct the tax calculation. . For example, when the tax-inclusive amount calculated based on the tax rate 1 is displayed (step B24), if the tax 1 calculation key 11b1 is operated (step B25: Yes), the CPU 21 stores it in the buffer memory area 22n. The read numerical value (number) is read out and displayed as the tax-excluded amount (step B26). As described above, at this time, that is, immediately after the tax-inclusive calculation (immediately after executing steps B22 and B23), the value of the tax-excluded amount used in the tax-inclusive calculation is stored in the buffer memory area 22n. When the tax-excluded amount is displayed (step B26), if the tax-one calculation key 11b1 is operated (step B27: Yes), the CPU 21 sets the numerical value (tax-excluded amount) stored in the buffer memory area 22n. ) Is read out, the tax amount is calculated again based on the read out numerical value and the tax rate 1, and the numerical value is displayed on the display unit 12 (step B28). Further, when the tax 1 calculation key 11b1 is continuously operated (step B29: Yes), the CPU 21 reads out the numerical value (excluding tax) stored in the buffer memory area 22n, and reads the read numerical value and the tax rate 1. The tax-inclusive amount is calculated again based on the calculated value, and the numerical value is displayed on the display unit 12 (step B24).

  In this way, the calculator 10 calculates the tax-inclusive amount in accordance with the operation of the tax-one calculation key 11b1, and then displays each of the tax-inclusive amount, the tax-excluded amount, and the tax amount for each operation on the tax-one calculation key 11b1. , Can be switched and displayed. Therefore, the tax-inclusive amount, the tax-excluded amount, and the tax amount can be easily confirmed.

  On the other hand, when the tax total recall mode is on (step B21: No), the CPU 21 stores the first tax-included total amount indicating the total of the tax-inclusive amount calculated based on the tax rate 1 for at least one numerical value, in the tax rate 1 total memory. The data is read from the area 22c and displayed on the display unit 12 (step B30). The transition to the ON state of the tax total recall mode will be described later.

  Further, when the tax 1 calculation key 11b1 is operated in the state where the first tax-included total amount is displayed (step B31, Yes), the CPU 21 corresponds to the first tax-included total amount from the tax rate 1 total memory area 22c. The first total tax-excluded amount (total tax-excluded amount) is read out and displayed (step B32). Further, when the first tax exemption amount is displayed and the tax 1 calculation key 11b1 is operated (step B33: Yes), the CPU 21 determines from the tax rate 1 total memory area 22c the first tax-included total amount. One tax total amount (total tax amount) is read and displayed (step B34). Furthermore, when the tax 1 calculation key 11b1 is operated in the state where the first tax total amount is displayed (step B35: Yes), the CPU 21 reads out and displays the first tax total total amount from the tax rate 1 total memory area 22c. (Step B30).

  That is, when the tax total recall mode is on, the calculator 10 displays the first total tax-included amount, the first total tax-excluded total amount, and the first tax-exclusive amount calculated based on the tax rate 1 for each operation on the tax 1 calculation key 11b1. The display of the total amount can be sequentially switched. Therefore, after the tax calculation for a plurality of numerical values at the tax rate 1, the first tax total amount, the first tax-excluded total amount, and the first tax total amount can be easily calculated as a result of the multiple tax calculations using the tax rate 1. Can be confirmed.

  When the tax total recall mode is on (step B21: No), the CPU 21 detects that any of the plurality of tax calculation keys 11b (11b0 to 11b4) has been operated (step B31: No). , Step B33: No, Step B35: No), the process proceeds to the calculation process corresponding to the operated tax calculation key 11b (Steps B36 to B39), and the same processes as those in Steps B21 to B35 described above are executed.

  For example, when it is detected that the tax 0 calculation key 11b0 has been operated in a state where any of the first total tax-included amount, the first total tax-excluded total amount, and the first tax total amount is displayed (step B31: No, (Step B33: No, Step B35: No → Step B36: Yes), the CPU 21 proceeds to a tax rate 0 calculation process (Step B6). In this case, since the tax total recall mode is in the ON state, the CPU 21 reads out the 0th tax-included total amount (the total amount including tax at the tax rate 0) from the tax rate 0 total memory area 22b and displays the same as in step B30 described above. When the tax 0 calculation key 11b1 is operated in a state where the 0th tax-included total amount is displayed, similarly to step B32 described above, the CPU 21 reads the 0th tax-excluded total amount (tax rate 0) from the tax rate 1 total memory area 22c. Of the tax excl.) Is displayed. Further, when the tax 0 calculation key 11b0 is operated in a state in which the 0th tax-excluded total amount is displayed, the CPU 21 reads the 0th tax total amount (tax rate 0) from the tax rate 0 total memory area 22b as in the above-described step B34. The total amount of tax is read out and displayed.

  Similarly, when the CPU 21 detects that the tax 2 calculation key 11b2 has been operated (step B37: Yes), the CPU 21 shifts to a tax rate 2 calculation process (step B7) and executes the same process as described above. When the CPU 21 detects that the tax 3 calculation key 11b3 has been operated (step B38: Yes), the CPU 21 shifts to the tax rate 3 calculation process (step B8), and determines that the tax 4 calculation key 11b4 has been operated. Is detected (Step B27: Yes), the process proceeds to the tax rate 4 calculation process (Step B9), and the same process as described above is executed. If it is detected that the tax calculation total key 11c has been operated (step B40: Yes), the CPU 21 displays the total tax-included amount, the total tax-excluded amount, and the total tax amount calculated at each tax rate. (Steps A29 to A214 described later). If the CPU 21 has not detected that the tax calculation total key 11c has been operated (step B40: No), the CPU 21 returns to the standby state for the input operation. In addition, in the tax rate 0 calculation processing, the tax rate 2 calculation processing, the tax rate 3 calculation processing, and the tax rate 4 calculation processing, when the operation of the tax 1 calculation key 11b1 is detected, as shown in FIG. The process proceeds (step B10).

  In each of the calculation processes of the tax rates 0 to 4, the tax calculation keys 11b corresponding to the other tax rates are operated while the tax total recall mode is in the ON state, thereby corresponding to the operated tax calculation keys 11b. By shifting to another calculation process, the total tax-included amount, the total tax-excluded amount, and the total tax amount calculated based on the tax rate corresponding to the other calculation process can be displayed.

  Therefore, when the tax total recall mode is in the ON state, by selecting one of the plurality of tax calculation keys 11b (11b0 to 11b4), the calculation is performed based on the tax rate corresponding to the operated tax calculation key 11b. , The total amount including tax, the total amount without tax, and the total amount of tax can be easily checked.

  Next, the tax exclusion calculation processing in the present embodiment will be described with reference to the flowchart shown in FIG. Here, a case where the tax 1 calculation key 11b1 is operated will be described. When the tax 0 calculation key 11b0, the tax 2 calculation key 11b2, the tax 3 calculation key 11b3, and the tax 4 calculation key 11b4 are operated, the same processing as when the tax 1 calculation key 11b1 is operated is executed. Detailed description is omitted.

  When the CPU 21 detects that the tax 1 calculation key 11b1 has been operated, the CPU 21 reads a numerical value (numeric value) stored in the display memory area 22p, and uses the read numerical value as a tax-inclusive amount. Based on the tax rate 1 (“5%”), which is the tax rate corresponding to the tax calculation key 11b on which the input operation has been performed, the tax-excluded amount is calculated (step C13). The CPU 21 stores the numerical value used for the tax exclusion calculation stored in the display memory area 22p in the buffer memory area 22n, and stores the numerical value of the tax exclusion amount calculated based on the tax rate 1 in the display memory area 22p. It is stored (step C2). Further, the CPU 21 causes the display unit 12 to display the tax-excluded amount calculated based on the tax rate 1 (step C3).

  In the state where the tax-excluded amount is displayed, the display of the tax-excluded amount and the tax amount can be switched by continuously operating the tax 1 calculation key 11b1 operated to instruct the tax calculation. For example, when the tax-excluded amount calculated based on the tax rate 1 is displayed (step C3), and the tax 1 calculation key 11b1 is operated (step C4: Yes), the CPU 21 stores the data in the buffer memory area 22n. The stored numerical value (tax included) is read out, the tax amount is newly calculated based on the read numerical value and the tax rate 1, and the numerical value is displayed on the display unit 12 (step C5). Further, when the tax 1 calculation key 11b1 is continuously operated (step C6: Yes), the CPU 21 reads out the numerical value (tax-excluded amount) stored in the buffer memory area 22n, and displays the read numerical value on the display unit 12. It is displayed (step C3).

  In this way, after calculating the tax-excluded amount in accordance with the operation of the tax-one calculation key 11b1, the calculator 10 alternately switches the display of the tax-excluded amount and the tax amount for each operation on the tax-one calculation key 11b1. Can be displayed. Therefore, the tax-excluded amount and the tax amount can be easily confirmed.

  In the tax exclusion calculation process, even if an operation is performed on the tax 1 calculation key 11b1, the tax-inclusive amount is not displayed. In the tax-inclusive calculation processing, the calculation result calculated according to the operation on the tax calculation key 11b is reflected (added) to the tax rate 1 total memory area 22c. In the tax-excluded calculation processing, the calculation result is calculated in the tax rate 1 total memory area 22c. Do not reflect on.

  On the other hand, the numerical value (tax-excluded amount) calculated by the tax-excluded calculation in step C3 can be used as a numerical value to continue execution of the tax-inclusive calculation using a different tax rate or the normal calculation.

  For example, in a market such as India that uses a plurality of consumption tax rates, it is represented by MRP (abbreviation of Maximum Retail Price: retail price = tax included). Therefore, when calculating the tax-inclusive amount using a different tax rate based on the tax-inclusive amount, after resetting the tax-inclusive amount to the tax-excluded amount, the tax-inclusive calculation according to the different tax rate is performed again, and the tax-excluded amount is calculated. You need to find the amount, tax included, and tax amount.

  In the calculator 10 according to the present embodiment, while the tax-inclusive calculation (total tax, total tax, and total tax) is being performed on a plurality of numerical values, when the tax-exclusive calculation is necessary as described above, Even if the tax calculation mode is switched from the tax-inclusive calculation mode to the tax-excluding calculation mode, the data of the tax total memory areas 22b to 22f corresponding to the respective tax rates 0 to 4 (calculation results up to the middle of the calculation) are discarded (cleared). Not). Therefore, even when the calculator 10 performs the tax-inclusive calculation and the tax-exclusive calculation in a mixed manner, the calculator 10 can switch and execute the tax calculation mode as needed, and thus can perform the tax calculation efficiently.

  Next, processing according to an input operation on the tax calculation total key ([GST GT (GT)]) 11c in the present embodiment will be described with reference to the flowchart shown in FIG. The tax calculation total key 11c includes a grand total key ([GT] key) for displaying a total total for the normal calculation (basic calculation) and a GST grand total key (for displaying the total total for the calculation result of the tax calculation). [GST GT] key).

  When detecting the operation of the tax calculation total key 11c (step A21: Yes), the CPU 21 determines whether the tax total recall mode flag is on (step A22). If the CPU 21 determines that the tax total recall mode flag is in the ON state (step A22: Yes), the process proceeds to step A29. In other words, the CPU 21 determines whether the numerical value indicating the result of the executed tax calculation or the normal calculation is being displayed on the display unit 12, that is, regardless of the display content of the display unit 12, Is determined to be on (Step A22: Yes), the process proceeds to Step A29. If it is determined that the tax total recall mode flag is in the ON state (step A22: No), the operation on the tax calculation total key 11c is a normal press (operation of keeping the pressed state for less than a predetermined time), or It is determined whether the operation is a long-press operation (an operation of continuing the pressed state for a predetermined time or more).

  Here, when it is determined that the operation is a normal pressing operation (step A23: No), the CPU 21 determines whether the operation immediately before the tax calculation total key 11c is pressed is the tax calculation. That is, the CPU 21 determines whether the tax calculation total key 11c has been operated immediately after the tax calculation in accordance with the operation of the tax calculation key 11b, in other words, whether the tax calculation total key 11c has been operated following the operation of the tax calculation key 11b. Is determined.

  Here, when it is determined that the tax calculation total key 11c has been operated immediately after the tax calculation (step A26: Yes), the CPU 21 turns on the tax total recall mode stored in the tax total recall mode area 22k (step A28). ). That is, the tax calculation total key 11c operated immediately after the tax calculation is used as a GST grand total key ([GST GT] key) for displaying a total sum of the calculation results of the tax calculation.

  In this case, the CPU 21 calculates the total amount based on the tax-inclusive amount, the tax-excluded total amount, and the tax-inclusive amount calculated based on each of the tax rates 0 to 4 stored in the tax total tax-specific memory areas 22b to 22f. The calculated total amount including tax, total amount excluding tax, and total amount of tax are calculated and stored in the total tax memory area 22g. In addition, the CPU 21 stores the calculated total sum including tax in the display memory area 22p and causes the display unit 12 to display the total sum (step A29).

  When the tax total sum is displayed (step A29), if the tax calculation total key 11c is operated (step A210: Yes), the CPU 21 reads out the tax total sum from the tax total memory area 22g, The information is stored in the display memory area 22p and displayed on the display unit 12 in place of the total sum including tax (step A211).

  Furthermore, when the tax total sum is displayed (step A211), if the tax calculation total key 11c is operated (step A212, Yes), the CPU 21 reads the tax total total from the tax total memory area 22g. Then, it is stored in the display memory area 22p and displayed on the display unit 12 in place of the total tax-excluded total amount (step A213).

  Further, when the total tax amount is displayed (step A213), if the total tax calculation key 11c is operated (step A214: Yes), the CPU 21 reads out the total total amount including tax from the total tax memory area 22g. Are stored in the display memory area 22p and displayed on the display unit 12 instead of the total tax amount (step A29).

  That is, the calculator 10 in the present embodiment calculates the total tax-included total in accordance with the operation of the tax calculation total key 11c, and corresponds to the total tax-included total and the total tax-included total for each operation on the tax calculation total key 11c. The display can be sequentially switched to the total amount excluding tax and the total amount corresponding to the total amount including tax. Therefore, it is possible to easily confirm the total amount including tax, the total amount excluding tax, and the total amount including tax.

  On the other hand, when the CPU 21 determines that the operation immediately before the tax calculation total key 11c is pressed is not the tax calculation, that is, the tax calculation total key 11c is operated immediately after the normal calculation (step A26: No), the total memory area The numerical value as a result of the normal calculation stored in 22h is read out, stored in the display memory area 22p, and displayed on the display unit 12 (step A27). That is, the tax calculation total key 11c operated immediately after the normal calculation is used as a grand total key ([GT] key) for displaying the total sum calculated by the normal calculation.

  Thus, in the calculator 10 according to the present embodiment, one tax calculation total key 11c is provided on the front of the housing having a limited area, and a grand total key ([GT] key) and a GST grand total key ([GST GT] key) ). The function of the tax calculation total key 11c is switched according to the state immediately before (immediately after tax calculation, immediately after normal calculation), so that the tax calculation total sum (tax total sum, tax-excluded total sum, tax total amount) The total sum of the ordinary calculations can be easily displayed.

  When detecting the operation of the tax calculation total key 11c (step A21: Yes), the CPU 21 determines that the operation on the tax calculation total key 11c is a long press operation (step A23: Yes), The processing is executed so as to display the calculation result opposite to the case where the calculation total key 11c is pressed.

  That is, when the tax calculation total key 11c is long-pressed (step A23: Yes), the CPU 21 determines that the operation of the tax calculation total key 11c is performed immediately after the tax calculation ( (Step A24: Yes), the numerical value as a result of the normal calculation stored in the total memory area 22h is read, stored in the display memory area 22p, and displayed on the display unit 12 (Step A27).

  When the tax calculation total key 11c is pressed and held (step A23: Yes), the CPU 21 determines that the operation of the tax calculation total key 11c is not performed immediately after the tax calculation (step A23). A24: No), the tax total recall mode stored in the tax total recall mode area 22k is turned on in the same manner as described above (step A28). Further, the CPU 21 sums up the respective tax rates based on the tax-inclusive amount, the tax-excluded total amount, and the tax total amount calculated based on the respective tax rates 0 to 4 stored in the tax total memory areas 22b to 22f for each tax rate. The total amount including tax, the total amount excluding tax, and the total amount are calculated and stored in the total tax memory area 22g. Further, the CPU 21 stores the calculated total sum including tax in the display memory area 22p and causes the display unit 12 to display the total sum (step A29).

  In this way, by long-pressing the tax calculation total key 11c, it is possible to execute a process reverse to that of the normal operation of pressing the tax calculation total key 11c. Thus, regardless of whether the tax calculation was performed immediately before operating the tax calculation total key 11c, the total of the tax calculation (total tax-included total, tax-excluded total, tax total) and the total of the normal calculation are calculated. The total can be easily switched and displayed only by changing the operation time (pressing time) for the tax calculation total key 11c.

  Next, an example of a specific numerical value input and tax calculation in the present embodiment will be described. Here, in order to facilitate the explanation, a tax using two tax 1 calculation keys 11b1 [GST + 1] (tax rate 1 (5%)) and a tax 2 calculation key 11b2 [GST + 2] (tax rate 2 (10%)) An example of calculation will be described. The tax calculation using the tax 0 calculation key 11b0, the tax 3 calculation key 11b3, and the tax 4 calculation key 11b4 is described as being executed in the same manner as when the tax 1 calculation key 11b1 and the tax 2 calculation key 11b2 are operated. Detailed description is omitted.

  FIGS. 8A and 8B show specific key operations used in the following description, numerical values displayed on the display unit 12, and stored in the tax rate 1 total memory area 22c and the tax rate 2 total memory area 22d, respectively. It shows the total amount including tax, the total amount excluding tax, the total amount of tax, and the total amount of the normal calculation stored in the total memory area 22h. The key operations shown in FIGS. 8A and 8B show an example in which the tax calculation and the normal calculation are executed in a mixed manner. FIG. 8A shows a key operation when the operation immediately before the operation of the tax calculation total key 11c is a tax calculation, and FIG. 8B shows an operation immediately before the operation of the tax calculation total key 11c is a tax. It shows the key operation when it is not the calculation. FIG. 9 shows a key operation and a display example on the display unit 12 shown in FIG.

  When the [AC] key 11a is operated, the CPU 21 clears the tax rate-specific tax total memory areas 22b to 22f (FIG. 9A). Further, the CPU 21 refers to the tax calculation mode area 22m, and determines [GST +] if it is determined that the current tax calculation mode is the tax-inclusive calculation mode, and [TAX-] if it determines that it is the tax-excluding calculation mode. Is displayed in the status display area of the display unit 12 as the tax calculation mode symbol 12b. As described above, even if the [AC] key 11a is operated, the tax calculation mode is not changed. Therefore, FIG. 9A shows a case where the tax calculation mode immediately before the operation of the [AC] key 11a is the tax-inclusive calculation mode. It is a display example.

  Thereafter, when a numerical value “200” is input for tax calculation, the CPU 21 stores the input numerical value in the display memory area 22p and causes the display unit 12 to display the input numerical value. Next, when the tax 1 calculation key 11b1 is operated, the CPU 21 causes the display unit 12 to display the tax-inclusive amount “210” calculated based on the tax rate 1 and “GST + 1” as the tax calculation key symbol 12c (FIG. 9 (B1)). Further, the CPU 21 stores the result of the tax calculation using the tax rate 1 with the tax 1 calculation key 11b1 in the tax rate 1 total memory area 22c. In this case, as shown in FIG. 7A, the total tax amount “210” of the tax rate 1, the total amount excluding tax “200” of the tax rate 1, and the total tax amount “10” of the tax rate 1 are stored in the tax rate 1 total memory area 22 c. Is stored. At the same time, the tax-excluded amount “200” is stored in the buffer memory area 22n (not shown).

  Next, when the keys “100”, “×”, “7”, and “=” are operated for the normal calculation, the CPU 21 executes the normal calculation of “100 × 7 = 700”, The numerical value of the calculation result “700” is stored in the display memory area 22p and displayed on the display unit 12 (FIG. 9 (B2)). Further, the CPU 21 stores the calculation result of the normal calculation in the total memory area 22h. Further, the CPU 21 causes “GT” to be displayed on the status display area of the display unit 12 as the total display symbol 12e.

  Next, when a numerical value “300” is input for tax calculation, the CPU 21 stores the input numerical value in the display memory area 22p and causes the display unit 12 to display the input numerical value. Next, when the tax 1 calculation key 11b1 is operated, the CPU 21 stores the tax included “315” calculated based on the numerical value “300” displayed on the display unit 12 and the tax rate 1 in the display memory area 22p. At the same time, it is displayed on the display unit 12. At the same time, the CPU 21 causes the display unit 12 to display the tax calculation key symbol “GST + 1” (FIG. 9 (B3)). Further, the CPU 21 stores the result of the tax calculation using the tax rate 1 with the tax 1 calculation key 11b1 in the tax rate 1 total memory area 22c. In this case, as shown in FIG. 7A, the tax-included amount “315” of the tax rate 1, the tax-excluded amount “300” of the tax rate 1, and the tax amount “15” of the tax rate 1 are the results of the tax calculation for the numerical value “300” as shown in FIG. Then, the tax-included total amount “210” of the tax rate 1, the tax-excluded total amount “200” of the tax rate 1, and the tax total amount “10” of the tax rate 1 are added to the previously stored total amount. As a result, the tax-included total amount “525” of the tax rate 1, the tax-excluded total amount “500” of the tax rate 1 and the tax total amount “25” of the tax rate 1 are stored in the tax-rate-1 total memory area 22c. At the same time, the tax-excluded amount “300” is stored in the buffer memory area 22n (not shown).

  Similarly, when the numerical value “1000” is input, the tax 2 calculation key 11b2 is operated, and then the numerical value “2000” is input and the tax 2 calculation key 11b2 is operated, the CPU 21 sets the tax 2 calculation key 11b2. For each of the operations of, the tax-excluded amounts (“1100” and “2200”) of the tax rate 2 calculated based on the respective tax-excluded amounts and the tax rate 2 are used as the tax-excluded amounts, respectively, in the display memory area 22p. And sequentially displayed on the display unit 12. At the same time, the CPU 21 displays the tax calculation key symbol “GST + 2” on the display unit 12 (FIGS. 9 (B4) and 9 (B5)). Further, the CPU 21 stores the result of the tax calculation using the tax rate 2 with the tax 2 calculation key 11b2 in the tax rate 2 total memory area 22d as shown in FIG. 7A. At the same time, the tax-excluded amount “1000” is first stored in the buffer memory area 22n, and then the tax-exclusive amount “2000” is stored in the buffer memory area 22n (not shown).

  Thus, the calculator 10 in the present embodiment can arbitrarily specify the tax rate used for the tax calculation for the input numerical value by operating the tax 1 calculation key 11b1 or the tax 2 calculation key 11b2. Therefore, for example, when calculating the total tax-included sum of a plurality of products having different applicable tax rates, even if a plurality of products having different applied tax rates are mixed, it is possible to individually specify the tax rate and input the tax-inclusive amount. . Also, the results of the tax calculation (tax included, tax excluded, tax) for the tax 1 calculation key 11b1 or the tax 2 calculation key 11b2 are individually stored in the tax rate 1 total memory area 22c and the tax rate 2 total memory area 22d. Can be kept. Therefore, as described later, in the tax total recall mode, the result of the tax calculation can be displayed for each tax rate according to the operation of the tax 1 calculation key 11b1 or the tax 2 calculation key 11b2.

  FIGS. 9 (C1) to 9 (C3) and FIG. 9 (F1) show display examples when the tax calculation total key [GST GT (GT)] 11c is operated (see FIG. 4).

  After performing the tax calculation for the plurality of numerical values shown in FIGS. 9 (B1) to 9 (B5), when the normal operation of pressing the tax calculation total key 11c is performed, the CPU 21 recalls the total tax because it is immediately after the tax calculation. Turn on the mode. Further, the CPU 21 determines the tax rate 1 and the tax rate 1 based on the tax-inclusive amount, the tax-excluded total amount, and the tax-inclusive amount of the tax rate 1 and the tax rate 2 stored in the tax rate 1 total memory area 22c and the tax rate 2 total memory area 22d to 22f, respectively. The total tax-included total amount “3825” indicating the total tax-included total amount (525 + 3300) to which the tax rate 2 is applied is calculated, stored in the tax total memory area 22g, and displayed on the display unit 12 (FIG. 7 (A) lower). , The third row, FIG. 9 (C1)). Further, the CPU 21 causes the status display area of the display unit 12 to display “RCL” as the tax total recall mode symbol 12d (FIG. 9 (C1)). Here, when the tax calculation total key 11c is operated, as shown in FIG. 9 (C2), the CPU 21 sets the total tax-excluded total amount indicating the total of the tax-excluded total amounts to which the tax rates 1 and 2 are applied, respectively. 3500 "is displayed. Further, when the tax calculation total key 11c is operated, as shown in FIG. 9 (C3), the CPU 21 changes the total tax amount “325” indicating the total of the total tax amounts to which the tax rates 1 and 2 are applied, respectively. Display. Further, when the tax calculation total key 11c is operated, the CPU 21 returns to the display shown in FIG. 9 (C1), reads out the total amount including tax “3825” from the tax total memory area 22g, and displays it on the display unit 12. .

  On the other hand, after performing tax calculation on a plurality of numerical values shown in FIGS. 9 (B1) to 9 (B5), when the tax calculation total key 11c is pressed and held, the CPU 21 integrates the normal calculation stored in the total memory area 22h. The total amount “700” is read and displayed (FIG. 8A, first line from the bottom, FIG. 9F1).

  Next, the case of the key operation shown in FIG. 8B will be described. Note that the tax calculation shown in FIG. 8B is performed in the same manner as in FIG. 8A described above, and a detailed description thereof will be omitted. In FIG. 8B, after the tax calculation (200 [GST + 1] 300 [GST + 1] 1000 [GST + 1] 2000 [GST + 1]) for a plurality of numerical values, the normal calculation (100 [×] 7 [=]) is executed. Immediately after that, the tax calculation total key 11c is operated.

  In this case, the CPU 21 displays the total sum “700” of the normal calculation stored in the total memory area 22h in response to the operation on the tax calculation total key 11c (the third line from the bottom in FIG. 9 (F1)).

  On the other hand, when the tax calculation is performed on the plurality of numerical values shown in the first to sixth lines in FIG. 8B and the tax calculation total key 11c is pressed and held, the CPU 21 turns on the tax total recall mode. Further, the CPU 21 determines the tax rate 1 and the tax rate 2 based on the tax-included amount, the tax-excluded total amount, and the tax total amount of the tax rates 1 and 2 stored in the tax rate 1 total memory area 22c and the tax rate 2 total memory area 22d, respectively. Is calculated and stored in the tax total memory area 22g, and displayed on the display unit 12 (FIG. 8 (B)). Line, FIG. 9 (C1)). Further, the CPU 21 causes the status display area of the display unit 12 to display “RCL” as the tax total recall mode symbol 12d (FIG. 9 (C1)).

  Thus, by operating (short-pressing) the tax calculation total key 11c immediately after the normal calculation, or by long-pressing the tax calculation total key 11c immediately after the tax calculation, the total sum by the normal calculation can be displayed. . As described above, the tax calculation total key 11c is operated (short-pressed) immediately after the tax calculation, or the tax calculation total key 11c is pressed and held immediately after the normal calculation, thereby displaying the total sum by the tax calculation. Therefore, one tax calculation total key 11c can be properly used according to the immediately preceding operation state.

  Next, a case where the tax 1 calculation key 11b1 or the tax 2 calculation key 11b2 is operated after the tax total recall mode is turned on will be described.

  FIGS. 9D1 to 9D3 show display examples when the tax 1 calculation key 11b1 is operated. When the tax 1 calculation key 11b1 is operated in a state where the displays shown in FIGS. 9 (C1) to 9 (C3) are displayed, the CPU 21 calculates the tax based on the tax rate 1 as shown in FIG. 9 (D1). The first total tax included “525” is displayed. Here, when the tax 1 calculation key 11b1 is operated, the CPU 21 displays the first total tax-excluded amount “500” as shown in FIG. 9 (D2). Further, when the tax 1 calculation key 11b1 is operated, the CPU 21 displays the first tax total amount “25” as shown in FIG. 9 (D3). Further, when the tax 1 calculation key 11b1 is operated, the CPU 21 returns to the display shown in FIG. 9 (D1) and displays the first total tax-included amount “525”.

  When the tax 2 calculation key 11b2 is operated in the display states shown in FIGS. 9 (D1) to 9 (D3), the CPU 21 displays the second total tax-included amount shown in FIG. 9 (E1) described below. Switch to When the tax calculation total key 11c is operated in the display states shown in FIGS. 9 (D1) to 9 (D3), the CPU 21 switches to the display state of the tax-inclusive total amount shown in FIG. 9 (C1). Transition.

  FIGS. 9 (E1) to (E3) show display examples when the tax 2 calculation key 11b2 is operated. When the tax 2 calculation key 11b2 is operated in the state where the display shown in FIGS. 9 (C1) to 9 (C3) is displayed, the CPU 21 calculates the tax based on the tax rate 2 as shown in FIG. 9 (E1). The second total tax included "3300" is displayed. Here, when the tax 2 calculation key 11b2 is operated, the CPU 21 displays the second total tax-excluded amount “3000” as shown in FIG. 9 (E2). Further, when the tax 2 calculation key 11b2 is operated, the CPU 21 displays the second total tax amount “300” as shown in FIG. 8 (E3). Further, when the tax 2 calculation key 11b2 is operated, the CPU 21 returns to the display shown in FIG. 9 (E1) and displays the second total tax-included amount “3300”.

  When the tax 1 calculation key 11b1 is operated in the display states shown in FIGS. 9 (E1) to 9 (E3), the CPU 21 switches to the display of the first total tax-included amount shown in FIG. 9 (D1). When the tax calculation total key 11c is operated in the display states shown in FIGS. 9 (E1) to (E3), the CPU 21 switches the display state of the tax-inclusive total amount shown in FIG. 9 (C1) described above. Transition.

  In this way, the calculator 10 in the present embodiment can operate the tax 1 calculation key 11b1 and the tax 2 calculation key 11b2 while the tax total recall mode is in the ON state, so that the tax included in the tax rates 1 and 2 can be included. The total amount, the total amount excluding tax, and the total amount of tax can be switched and displayed. Therefore, the total amount including tax, the total amount before tax, and the total amount of tax for each tax rate can be easily confirmed.

  Further, the calculator 10 in this embodiment displays the total sum by operating the tax calculation total key 11c, the tax 1 calculation key 11b1, and the tax 2 calculation key 11b2 while the tax total recall mode is on. ) To (C3)), the total display of the tax rate 1 corresponding to the tax 1 calculation key 11b1 (FIGS. 9 (D1) to (D3)), and the total display of the tax rate 2 corresponding to the tax 2 calculation key 11b2 (FIG. 9). (E1) to (E3)).

  Next, a case will be described in which the tax-inclusive calculation and the tax-exclusive calculation are performed in a mixed manner. FIG. 10 shows a specific key operation used in the following description, a numerical value displayed on the display unit 12, a total tax-included amount stored in each of the tax rate 1 total memory area 22c and the tax rate 2 total memory area 22d, and excluding tax. Shows total amount and total tax amount.

  The key operations shown in FIGS. 8A and 8B described above are for the case of executing only the tax-inclusive calculation. However, the key operations shown in FIG. 10 change the calculation mode during the tax-inclusive calculation to the tax-excluding calculation mode. In the example shown in FIG.

  When the [AC] key 11a is operated, the CPU 21 clears the tax rate-based total tax memory areas 22b to 22f. Here, the calculation mode is the tax-inclusive calculation mode, and [GST +] indicating the tax-inclusive calculation mode is displayed on the display unit 12 as the tax calculation mode symbol 12b.

  After that, for tax calculation (calculation including tax), the numerical value “200” is input as a tax-excluded amount, and when the tax 1 calculation key 11b1 ([GST + 1 (TAX-1)]) is operated, the CPU 21 is input. In addition to storing the calculated value in the buffer memory area 22n, the tax-excluded amount “210” calculated by the tax-inclusive calculation based on the tax-excluded amount and the tax rate 1, and the tax-inclusive amount calculated based on the tax rate 1 are displayed. Is displayed. Further, the CPU 21 stores the result of the tax calculation using the tax rate 1 with the tax 1 calculation key 11b1 in the tax rate 1 total memory area 22c. In this case, as shown in FIG. 9, the total tax amount “210” of the tax rate 1, the total tax amount “200” of the tax rate 1, and the total tax amount “10” of the tax rate 1 are stored in the tax rate 1 total memory area 22 c. You.

  Similarly, when the numerical value “300” is input as a tax-excluded amount for tax calculation and the tax 2 calculation key 11b2 is operated, the CPU 21 stores the input numerical value in the buffer memory area 22n, The tax-inclusive amount “330” calculated by the tax-inclusive calculation based on the tax-excluded amount and the tax rate 2 and the symbol “GST + 2” indicating that the tax-inclusive amount calculated based on the tax rate 2 is displayed. In addition, the CPU 21 stores the result of the tax calculation using the tax rate 2 with the tax 2 calculation key 11b2 in the tax rate 2 total memory area 22d. In this case, as shown in FIG. 10, the tax-included total amount “330” of the tax rate 2, the tax-excluded total amount “300” of the tax rate 2, and the tax total amount “30” of the tax rate 2 are stored in the tax-rate-2 total memory area 22d. You.

  Next, when the tax 2 calculation key 11b2 is operated in a state where the tax-included total amount “330” of the tax rate 2 is displayed, the CPU 21 sets the numerical value “300” as the tax-excluded amount stored in the buffer memory area 22n. Is read and displayed on the display unit 12.

  Here, it is assumed that the tax calculation mode switching key 11d ([GST + / TAX-]) has been operated to set the calculation mode to the tax-excluding calculation mode. When detecting the operation of the tax calculation mode switching key 11d, the CPU 21 switches the calculation mode to the tax-excluding calculation mode. Further, the CPU 21 causes the display unit 12 to display [TAX-] indicating the tax-inclusive calculation mode as the tax calculation mode symbol 12b.

  After that, for the tax calculation (calculation without tax), the numerical value “660” is input as the tax-inclusive amount, and when the tax 2 calculation key 11b2 ([GST + 2 (TAX−2)]) is operated, the CPU 21 inputs the value. The stored value is stored in the buffer memory area 22n, and the tax-excluded amount “600” calculated by the tax-excluded calculation based on the tax-inclusive amount and the tax rate 2 and the tax-excluded amount calculated based on the tax rate 2 are displayed. Is displayed, the symbol "TAX-2" indicating that the user is present. In the tax exclusion calculation, as shown in FIG. 10, the result of the tax exclusion calculation is not reflected in the tax rate 2 total memory area 22d.

  Here, it is assumed that the tax calculation mode switching key 11d ([GST + / TAX-]) has been operated to set the calculation mode to the tax-inclusive calculation mode. When detecting the operation of the tax calculation mode switching key 11d, the CPU 21 switches the calculation mode to the tax-inclusive calculation mode.

  Thereafter, when the tax 1 calculation key 11b1 ([GST + 1]) is operated in a state where the numerical value “600” is displayed by the tax exclusion calculation for the tax calculation (tax included calculation), the CPU 21 displays the displayed value. A tax-included amount “630” calculated by the tax-inclusive calculation based on the numerical value and the tax rate 1 and a symbol “GST + 1” indicating that the tax-inclusive amount calculated based on the tax rate 1 is displayed. Further, the CPU 21 adds the result of the tax calculation (tax-excluded amount, tax-inclusive amount, tax amount) using the tax rate 1 by the tax 1 calculation key 11b1 to the numerical value previously stored in the tax rate 1 total memory area 22c. As a result, the tax rate 1 total memory area 22c stores the tax rate 1 total tax amount "840", the tax rate 1 tax-excluded total amount "800", and the tax rate 1 tax total amount "30".

  As described above, when the tax-inclusive calculation based on the tax rate 1 is performed on the numerical value “660” indicating the tax-inclusive amount based on the tax rate 2, the mode is switched to the tax-excluding calculation mode during the tax-inclusive calculation, and the tax-excluded amount of the numerical value “660” is calculated. Tax exemption calculations can be performed. The numerical value (numeric value) displayed on the display unit 12 as the calculation result of the tax exclusion calculation can be directly subjected to the tax calculation. In addition, the tax exclusion calculation does not affect the numerical values stored in the tax rate 1 total memory area 22c and the tax rate 2 total memory area 22d. Therefore, the tax calculation mode is switched to the tax-inclusive calculation mode again, another tax rate 1 is selected for the numerical value being displayed, and the tax-inclusive calculation is executed. This can be reflected in the area 22c.

  Therefore, in a market such as India where multiple consumption tax rates are used, if tax calculation is required at another tax rate based on the price of the product indicated with the tax included, switch to the tax exemption calculation mode. The tax-excluded calculation is performed to obtain the price of the tax-excluded amount, and the tax-inclusive calculation at another tax rate can be executed again.

  Next, a case where the tax calculation and the normal calculation are executed in a mixed manner will be described. FIG. 11 shows specific key operations used in the following description, numerical values displayed on the display unit 12, the total tax-included amount stored in each of the tax rate 1 total memory area 22c and the tax rate 2 total memory area 22d, and excluding tax. Shows total amount and total tax amount. Here, an example will be described in which the four arithmetic calculations are executed using a numerical value (number) obtained by the tax calculation. Note that the downward arrows in the third to eighth columns in FIG. 10 are the same as the values in the fifth row in each column from the sixth row to the second row in each column from the bottom row to the second row (the numerical values are Does not change).

  When the [AC] key 11a is operated, the CPU 21 clears the tax rate-based total tax memory areas 22b to 22f. Here, the calculation mode is the tax-inclusive calculation mode, and [GST +] indicating the tax-inclusive calculation mode is displayed on the display unit 12 as the tax calculation mode symbol 12b.

  Next, when the numerical value “200” is input as the tax-excluded amount and the tax 1 calculation key 11b1 is operated, the CPU 21 stores the input numerical value in the buffer memory area 22n and sets the tax-excluded amount and the tax rate 1 together. A tax-inclusive amount “210” calculated based on the tax-inclusive calculation and a symbol “GST + 1” indicating that the tax-inclusive amount calculated based on the tax rate 1 are displayed. Further, the CPU 21 stores the result of the tax calculation using the tax rate 1 with the tax 1 calculation key 11b1 in the tax rate 1 total memory area 22c. In this case, as shown in FIG. 11, the total tax amount “210” of the tax rate 1, the total amount excluding tax “200” of the tax rate 1, and the total tax amount “10” of the tax rate 1 are stored in the tax rate 1 total memory area 22 c. You.

  Similarly, when the numerical value “200” is input as the tax-excluded amount and the tax 1 calculation key 11b1 is operated, the CPU 21 stores the input numerical value in the buffer memory area 22n, and also sets the tax-excluded amount and the tax rate 1 The tax-inclusive amount “315” calculated based on the tax-inclusive calculation is displayed. Further, the CPU 21 adds the result of the tax calculation using the tax rate 1 to the numerical value stored in the tax rate 1 total memory area 22c. As a result, as shown in FIG. 11, the tax-included total amount “525” of the tax rate 1, the tax-excluded total amount “500” of the tax rate 1 and the tax total amount “25” of the tax rate 1 are stored in the tax-rate-1 total memory area 22c. You.

  Subsequently, when the numerical value “1000” is input as the tax-excluded amount and the tax 2 calculation key 11b2 is operated, the CPU 21 stores the input numerical value in the buffer memory area 22n and sets the tax-excluded amount and the tax rate 2 together. A tax included amount “1100” calculated based on the tax included calculation and a symbol “GST + 2” indicating that the tax included amount calculated based on the tax rate 2 is displayed. In addition, the CPU 21 stores the result of the tax calculation using the tax rate 2 with the tax 2 calculation key 11b2 in the tax rate 2 total memory area 22d. In this case, as shown in FIG. 11, the total tax amount “1100” including tax at the tax rate 2, the total tax amount “1000” at the tax rate 2 and the total tax amount “100” at the tax rate 2 are stored in the tax rate 2 total memory area 22d. You.

  Similarly, when the numerical value “2000” is input as the tax-excluded amount and the tax 2 calculation key 11b2 is operated, the CPU 21 stores the input numerical value in the buffer memory area 22n, and sets the tax-excluded amount and the tax rate 2 The tax-inclusive amount “2200” calculated based on the tax-inclusive calculation is displayed. Further, the CPU 21 adds the result of the tax calculation using the tax rate 2 to the numerical value stored in the tax rate 2 total memory area 22d. As a result, as shown in FIG. 11, the total tax amount “3300” including the tax rate 2, the total amount excluding tax “3000” at the tax rate 2 and the total tax amount “300” at the tax rate 2 are stored in the tax rate 2 total memory area 22 d. You.

  Here, it is assumed that a normal operation of pressing the tax calculation total key 11c is performed to display the total sum of the tax calculations. The CPU 21 detects that the tax calculation total key 11c has been operated, and determines whether the tax total recall mode is on. When the CPU 21 detects that the tax total recall mode is not in the ON state and is an operation immediately after the tax calculation, the CPU 21 sets the tax total recall mode to the ON state and indicates that the tax total recall mode is in the ON state. Is displayed on the display unit 12. “RCL” on the left outside the table in FIG. 11 indicates that the corresponding line is being displayed and the recall mode is set. Further, the downward arrow indicates that the recall mode is continued from the sixth line to the second line from the bottom, that is, immediately before the [AC] key is pressed.

  When the tax total recall mode is turned on, the CPU 21 stores the tax-included total amount “3825” obtained by adding the tax-included total amounts calculated based on the tax rates 1 and 2 in the tax total memory area 22g and , On the display unit 12. Here, when the tax calculation total key 11c is repeatedly operated, the CPU 21 sequentially calculates the total tax total amount “3500” and the total tax total “325” in accordance with the key operation, and calculates the total tax amount “325”. The information is stored in the area 22g and read out from the display unit 12 for display.

  In the state where the total tax amount “325” is displayed, when [÷] [2] [=] is key-input for the four arithmetic calculations, the CPU 21 changes the numerical value “325” displayed on the display unit 12. On the other hand, the four arithmetic calculations of “325/2 = 162.5” are executed, and the numerical value “162.5” as the calculation result is displayed on the display unit 12. The numerical value “162.5” is stored in the total memory area 22h. In addition to displaying the total tax amount and executing the four arithmetic calculations, it is also possible to display the total tax amount or the total tax-excluded total value and execute the four arithmetic calculations.

  As described above, even if the operation key or the numerical key is operated for the four arithmetic calculations during the tax calculation, the on-state of the tax total recall mode is maintained. Further, the numerical values stored in the tax rate 1 total memory area 22c, the tax rate 2 total memory area 22d, and the tax total memory area 22g stored by the tax calculation are also maintained.

  Here, it is assumed that a normal operation of pressing the tax calculation total key 11c is performed to display the total sum of the tax calculations. When detecting that the tax calculation total key 11c has been operated, the CPU 21 determines whether the tax total recall mode is on. At this time, the tax total recall mode is already on. Therefore, the CPU 21 causes the display unit 12 to display the total tax included in the tax total memory area 22g in response to the operation on the tax calculation total key 11c. That is, in a state in which the tax total recall mode is set to the ON state, when an instruction to read the total amount including tax is input by operating the tax total key 11c, the CPU 21 causes the numerical value “162” of the result of executing the four arithmetic calculations. During the display of “.5”, the numerical value “3825” of the total sum including tax stored in the display memory area 22p is read and displayed on the display unit 12.

  Next, it is assumed that the tax 1 calculation key 11b1 is operated in order to display the total amount including tax in the tax calculation using the tax rate 1. When the tax 1 calculation key 11b1 is operated, since the tax total recall mode is on, the CPU 21 replaces the display of the tax-inclusive total amount “3825” with the first tax rate 1 total memory area 22c. The numerical value “525” of the total amount including tax is read out and displayed on the display unit 12.

Here, when the tax calculation total key 11c is operated again, the CPU 21 responds to the operation on the tax calculation total key 11c in the same manner as described above, and the tax-included total amount stored in the tax total memory area 22g " 3825 "is displayed on the display unit 12. That is, in the state where the tax total recall mode is set to the ON state, the numerical value of the calculation result by the tax calculation is displayed on the display unit 12 as well as the numerical value as the calculation result of the normal calculation by the four arithmetic calculations. In this case, the total sum including tax can be displayed according to the operation on the tax calculation total key 11c. That is, after the tax total recall mode is set to the ON state, the total sum including tax can be displayed regardless of the display content when the tax calculation total key 11c is operated. It is assumed that the tax 2 calculation key 11b2 has been operated in order to display the total amount including tax in the tax calculation using the tax rate 2. When the tax 2 calculation key 11b2 is operated, in response to the operation of the tax 2 calculation key 11b2, the CPU 21 replaces the display of the tax-inclusive total amount “3825” with the second tax rate 2 total memory area 22d. The total amount including tax “3300” is read and displayed on the display unit 12.

  That is, as shown in FIG. 11, the numerical value related to the result of the tax calculation based on the tax rate 1 is stored in the tax rate 1 total memory area 22c, and the numerical value related to the result of the tax calculation based on the tax rate 2 is stored in the tax rate 2 total memory area 22d. If it is stored, in a state where the tax total recall mode is set to the ON state, the numerical value (total amount including tax) stored in the tax rate 1 total memory area 22c is read in response to the operation of the tax 1 calculation key 11b1. Similarly, according to the operation of the tax 2 calculation key 11b2, the numerical value (total tax included) stored in the tax rate 2 total memory area 22d can be read and displayed.

  Although not shown, numerical values related to the results of the tax calculations based on the tax rates 0, 3, and 4 are stored in the tax rate 0 total memory area 22b, the tax rate 3 total memory area 22e, and the tax rate 4 total memory area 22f, respectively. Then, according to the operation of the tax 0 calculation key 11b0, the tax 3 calculation key 11b3, or the tax 4 calculation key 11b4, the corresponding numerical value (total amount including tax) can be read and displayed.

  In the above description, at least the tax-inclusive total is displayed according to the operation of the tax n calculation keys 11b0 to 11b4 when the tax total recall mode is on, but both the tax-excluding total and the tax total, or One of them may be displayed.

  Next, when the tax 2 calculation key 11b2 is repeatedly operated in a state where the second total tax amount “3300” is displayed, the CPU 21 sets the total tax amount “3000” and the total tax amount in accordance with the key operation. The amount “300” is read from the tax rate 2 total memory area 22 d and sequentially displayed on the display unit 12.

  In the state where the total tax amount “300” is displayed, if [÷] [2] [=] is key-input for the four arithmetic calculations, the CPU 21 causes the numerical value “300” displayed on the display unit 12 to be changed. Then, the four arithmetic calculations of “300 ÷ 2 = 150” are executed, and the numerical value “150” as the calculation result is displayed on the display unit 12. The numerical value “150” is added to the numerical value stored in the total memory area 22h. In addition to displaying the total amount of tax and executing the four basic calculations, it is also possible to display the total amount including tax or the total amount excluding tax and perform the four basic calculations.

  When detecting that the [AC] key has been operated, the CPU 21 turns off the tax total recall mode and clears all memories including the tax total memory areas 22b to 22f for each tax rate and the tax total memory area 22g. I do.

  In this way, the tax total recall mode is kept on until the [AC] key is operated. Then, when the tax total recall mode is in the ON state, the numerical values stored in the tax total memory areas 22b to 22f for each tax rate are displayed on the display unit 12 by operating the tax calculation key 11b, and are set as the targets of the normal calculation. can do.

  As described above, in the calculator 10 according to the present embodiment, the tax total recall mode is maintained in the ON state even if the normal calculation is performed while the tax total recall mode is in the ON state. Then, each calculation result can be stored. Therefore, it is possible to easily execute the tax calculation and the normal calculation together. In addition, the total amount based on the tax calculation stored in the total tax memory area 22g (the total total amount including tax, the total amount excluding tax, the total total tax amount), or the calculation based on each tax rate stored in the tax rate 1 total memory area 22c. The results (the total amount including tax, the total amount before tax, and the total amount of tax) can be displayed on the display unit 12 in response to a key operation, and can be subjected to normal calculation. Therefore, it is possible to easily execute the normal calculation on the result (the number) of the tax calculation.

  FIG. 12 shows an example of a voucher format used in an Indian retail store, in which an entry column for the total amount is extracted. The slip can be filled in numerical values for each of the five tax rates. From the top line, the total amount excluding tax by tax rate, State GST (SGST) by tax rate, Central GST (CGST) by tax rate, and by tax rate Inter-State GST (IGST), total tax-included amount by tax rate, and total tax-included total amount are provided. Numerical values are entered in each column according to the tax calculation actually performed at the store.

  The entry of numerical values into a slip will be described with reference to an input operation example shown in FIG. When the tax calculation total key 11c is operated immediately after the tax calculation, the tax total recall mode is turned on, and the total amount including tax “3825” is displayed on the display unit 12 (the sixth line in FIG. 11). The entry person sees this numerical value, and transcribes it in the column of “GTAND TOTAL” in the slip (the sixth line in FIG. 12). Subsequently, when the tax 2 calculation key 11b2 is operated, the second total tax-included amount “3300” is displayed on the display unit 12 (line 14 in FIG. 11), and the creator can enter the tax-included total of tax rate 2 in the slip. The numerical value is transferred to the amount column (the third column, the fifth row in FIG. 12). When the tax 2 calculation key 11b2 is operated again, the second total tax-excluded amount “3000” is displayed on the display unit 12 (line 15 in FIG. 11), and the entry is made by the tax-excluded total of the tax rate 2 in the slip. The numerical value is transferred to the amount column (third column, first row in FIG. 12). Next, when the tax 2 calculation key 11b2 is operated again, the total tax amount “300” of the tax rate 2 is displayed on the display unit 12 (line 16 in FIG. 11), and subsequently, using the numerical value being displayed, When half of the total tax amount of the tax rate 2 is calculated, “150” is displayed on the display unit 12 as an execution result of the normal calculation (line 18 in FIG. 11). The entry person transcribes a numerical value to each column of the tax rate 2 SGST and CGST in the slip (third column, second line, third line in FIG. 12). In this example, it is assumed that there is no particular value to be transferred to the IGST column. Although not illustrated in FIG. 10, by operating the tax 1 calculation key 11b1 in a state where the tax total recall mode is on, the tax calculation result or the tax calculation result can be obtained for the tax rate 1 as in the case of the tax rate 2. The result of the target normal calculation is displayed, and the numerical value can be transcribed to each column of the slip as shown in the second column of FIG.

  As described above, according to the calculator of the present embodiment, after the tax calculation is completed, the tax total recall mode is turned on, and subsequently, SGST, CGST, or IGST can be calculated. Moreover, once the tax total recall mode is turned on, the tax total recall mode is maintained on unless a specific operation ([AC] key operation) is performed, and the tax total tax memory areas 22b to 22f are maintained. Since each numerical value stored in the tax total memory area 22g is retained, after the tax calculation is completed, the total tax amount (tax included / tax amount) is operated by operating the tax calculation total key 11c or the tax calculation key 11b. Tax amount) or the total tax amount (tax-inclusive amount / tax-excluded amount / tax amount) for each of a plurality of tax rates can be called and displayed on the display unit 12 at any time. By executing, it is possible to calculate SGST, CGST, or IGST for the total tax amount or the total tax amount for each of a plurality of tax rates at a desired timing. Therefore, according to the calculator of the present embodiment, in particular, when the total tax amount and the total tax amount for each tax rate are not directly posted to the voucher, but the normal calculation based on each numerical value is performed and then the voucher is posted to the voucher. In addition, the posting operation to the slip becomes easy.

  The method described in the embodiment, that is, each method such as the processing shown in the flowcharts of FIGS. 3 to 7, can be executed by a computer as a program such as a memory card (ROM card, RAM card, etc.) It can be stored and distributed on a recording medium such as a flexible disk, a hard disk, an optical disk (CD-ROM, DVD, etc.), a semiconductor memory, or the like. Then, the computer reads the program recorded on the external recording medium, and the operation is controlled by the program, whereby the same processing as the function described in the embodiment can be realized.

  Also, program data for implementing each method can be transmitted over a network (Internet) in the form of a program code. Program data is transmitted from a computer (server device or the like) connected to the network (Internet). It is also possible to realize the same function as the above-described embodiment by taking in.

  The present invention is not limited to the embodiment, and can be variously modified in an implementation stage without departing from the scope of the invention. Further, the embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed components. For example, even if some components are deleted from all the components shown in the embodiments or some components are combined, the problem described in the section of the problem to be solved by the invention can be solved. In the case where the effect described in the section of the effect can be obtained, a configuration in which this component is deleted or combined can be extracted as an invention.

  Hereinafter, the invention described in the claims of the present application is additionally described.

[1] In response to input of an instruction to execute a first calculation, a first calculation using a numerical value is executed, a first numerical value related to a result of the executed first calculation is stored in a first memory, and a display unit is provided. To be displayed,
In response to an input of a second calculation execution instruction different from the first calculation, a second calculation using a numerical value is executed, and a second numerical value related to the result of the executed second calculation is stored in a second memory. , And displayed on the display unit,
When a first read instruction is input while a numerical value indicating the result of the executed first calculation is displayed on the display unit, the first numerical value stored in the first memory is displayed on the display unit. To be displayed,
While the numerical value indicating the result of the executed second calculation is displayed on the display unit, when the first read instruction is input, the second numerical value stored in the second memory is displayed on the display unit. A computer having a control unit to be displayed on a unit.

[2] The control unit includes:
The computer according to [1], wherein a read mode for displaying the first numerical value related to a result of the executed first calculation is set in response to an input of a read mode setting instruction.

  [3] The computer according to [2], wherein the first read instruction also serves as an instruction to set the read mode.

[4] The control unit:
In the state where the read mode is set,
In response to the input of the execution instruction of the second calculation, without canceling the set readout mode, the second calculation using the numerical value displayed on the display unit is performed, and the executed second calculation is performed. The computer according to [2] or [3], wherein a numerical value indicating a result is displayed on the display unit.

[5] The control unit includes:
In the state where the read mode is set,
In response to the input of the second read instruction, the first numerical value stored in the first memory is read and displayed on the display unit,
In response to the input of the execution instruction of the second calculation, without canceling the set readout mode, the second calculation is executed using the first numerical value displayed on the display unit, and the executed The computer according to any one of [2] to [4], wherein a numerical value indicating a result of the second calculation is displayed on the display unit.

  [6] The computer according to [5], wherein the execution instruction of the first calculation also serves as the second read instruction.

[7] The control unit includes:
In the state where the read mode is set,
The computer according to any one of [2] to [6], wherein the set read mode is canceled in response to input of a predetermined instruction.

[8] The control unit:
In the state where the read mode is set,
The computer according to any one of [2] to [7], wherein the content stored in the first memory is cleared in response to input of a predetermined instruction.

[9] The control unit:
In the state where the read mode is set,
When the first read instruction is input, the first numerical value stored in the first memory is displayed on the display unit regardless of the display content of the display unit, [2] to [2]. 8] The computer according to any one of the above items.

[10] The control unit includes:
In a state where the read mode is not set,
While the numerical value indicating the result of the executed first calculation is displayed on the display unit, when the first read instruction is input, the first numerical value stored in the first memory is displayed on the display unit. Section,
While the numerical value indicating the result of the executed second calculation is displayed on the display unit, when the first read instruction is input, the second numerical value stored in the second memory is displayed on the display unit. The computer according to any one of [2] to [9], which is displayed on a unit.

[11] The control unit includes:
When an instruction to execute the first calculation related to the first tax rate is input, the tax calculation based on the first tax rate is performed, and a third numerical value related to a result of the tax calculation based on the first tax rate is stored in the first memory. Remember
When an instruction to execute the first calculation related to the second tax rate is input, the tax calculation based on the second tax rate is performed, and a fourth numerical value related to the result of the tax calculation based on the second tax rate is stored in the first memory. Remember
The reading mode is set according to the input of the first reading instruction, and a total sum of the third numerical value and the fourth numerical value is displayed on the display unit. A computer according to any one of the preceding claims.

[12] The control unit includes:
When an instruction to execute the first calculation relating to any one of the plurality of tax rates is input, the tax calculation is performed at the one of the tax rates, and the tax calculation at the one of the tax rates is performed. Storing a numerical value related to the result in the first memory;
In the state where the read mode is set,
In response to input of an instruction to execute a function relating to any one of the tax rates, a total tax sum of at least one numerical value indicating a result of the tax calculation based on the one of the tax rates is displayed. [2] to [11] ] The computer according to any one of the above items.

[13] The control unit includes:
If a third read instruction different from the first read instruction is input while a numerical value indicating the result of the first calculation performed is displayed on the display unit, the third read instruction is stored in the second memory. The second numerical value is displayed on the display unit,
While the numerical value indicating the result of the executed second calculation is displayed on the display unit, when the third read instruction is input, the first numerical value stored in the first memory is displayed on the display unit. The computer according to any one of [1] to [12], which is displayed on a unit.

[14] The control unit:
According to the input of the switching instruction of the tax calculation mode, the calculation to be executed as the first calculation is switched to any of the calculation including tax and the calculation without tax,
When performing the tax-inclusive calculation as the first calculation, the first numerical value is stored in the first memory,
The computer according to any one of [1] to [13], wherein when performing the tax-excluded calculation as the first calculation, the first numerical value is not stored in the first memory.

[15] By computer of computer
In response to the input of the execution instruction of the first calculation, the first calculation using the numerical value is executed, the first numerical value related to the result of the first calculation executed is stored in the first memory, and displayed on the display unit. ,
In response to an input of a second calculation execution instruction different from the first calculation, a second calculation using a numerical value is executed, and a second numerical value related to the result of the executed second calculation is stored in a second memory. , And displayed on the display unit,
When a first read instruction is input while a numerical value indicating the result of the executed first calculation is displayed on the display unit, the first numerical value stored in the first memory is displayed on the display unit. To be displayed,
While the numerical value indicating the result of the executed second calculation is displayed on the display unit, when the first read instruction is input, the second numerical value stored in the second memory is displayed on the display unit. A program to be displayed on the unit, and to function as follows.

[16] A calculation method executed by a control unit of the computer,
In response to the input of the execution instruction of the first calculation, the first calculation using the numerical value is executed, the first numerical value related to the result of the first calculation executed is stored in the first memory, and displayed on the display unit. ,
In response to an input of a second calculation execution instruction different from the first calculation, a second calculation using a numerical value is executed, and a second numerical value related to the result of the executed second calculation is stored in a second memory. , And displayed on the display unit,
When a first read instruction is input while a numerical value indicating the result of the executed first calculation is displayed on the display unit, the first numerical value stored in the first memory is displayed on the display unit. To be displayed,
While the numerical value indicating the result of the executed second calculation is displayed on the display unit, when the first read instruction is input, the second numerical value stored in the second memory is displayed on the display unit. Calculation method to be displayed in the section.

  10 Calculator, 11 Key input section, 11b0 Tax 0 calculation key, 11b1 Tax 1 calculation key, 11b2 Tax 2 calculation key, 11b3 Tax 3 calculation key, 11b4 Tax 4 calculation key, 11c Tax calculation total Key, 11d: Tax calculation mode switching key, 12: Display unit, 21: CPU, 22: Memory, 22a: Calculation processing program, 22b: Tax rate 0 total memory area, 22c: Tax rate 1 total memory area, 22d: Tax rate 2 total Memory area, 22e: Tax rate 3 total memory area, 22f: Tax rate 4 total memory area, 22g: Tax total memory area, 22h: Total memory area, 22k: Tax total recall mode area, 22m: Tax calculation mode area.

Claims (16)

In response to the input of the execution instruction of the first calculation, the first calculation using the numerical value is executed, the first numerical value related to the result of the first calculation executed is stored in the first memory, and displayed on the display unit. ,
In response to an input of a second calculation execution instruction different from the first calculation, a second calculation using a numerical value is executed, and a second numerical value related to the result of the executed second calculation is stored in a second memory. , And displayed on the display unit,
When a first read instruction is input while a numerical value indicating the result of the executed first calculation is displayed on the display unit, the first numerical value stored in the first memory is displayed on the display unit. To be displayed,
While the numerical value indicating the result of the executed second calculation is displayed on the display unit, when the first read instruction is input, the second numerical value stored in the second memory is displayed on the display unit. To be displayed in the
A computer having a control unit. The control unit includes:
Setting a read mode for displaying the first numerical value related to the result of the executed first calculation in response to input of a read mode setting instruction;
The computer according to claim 1. The first read instruction also serves as a read mode setting instruction.
The computer according to claim 2. The control unit includes:
In the state where the read mode is set,
In response to the input of the execution instruction of the second calculation, without canceling the set readout mode, the second calculation using the numerical value displayed on the display unit is performed, and the executed second calculation is performed. Displaying a numerical value indicating the result on the display unit,
The computer according to claim 2 or 3. The control unit includes:
In the state where the read mode is set,
In response to the input of the second read instruction, the first numerical value stored in the first memory is read and displayed on the display unit,
In response to the input of the execution instruction of the second calculation, without canceling the set readout mode, the second calculation is executed using the first numerical value displayed on the display unit, and the executed Displaying a numerical value indicating a result of the second calculation on the display unit;
The computer according to claim 2. The instruction to execute the first calculation also serves as the second read instruction.
The computer according to claim 5. The control unit includes:
In the state where the read mode is set,
In response to the input of a predetermined instruction, cancel the set read mode,
A computer according to any one of claims 2 to 6. The control unit includes:
In the state where the read mode is set,
Clearing the storage content of the first memory in response to input of a predetermined instruction;
A computer according to any one of claims 2 to 7. The control unit includes:
In the state where the read mode is set,
When the first reading instruction is input, the first numerical value stored in the first memory is displayed on the display unit regardless of the display content of the display unit.
A computer according to any one of claims 2 to 8. The control unit includes:
In a state where the read mode is not set,
While the numerical value indicating the result of the executed first calculation is displayed on the display unit, when the first read instruction is input, the first numerical value stored in the first memory is displayed on the display unit. Section,
While the numerical value indicating the result of the executed second calculation is displayed on the display unit, when the first read instruction is input, the second numerical value stored in the second memory is displayed on the display unit. To be displayed in the
A computer according to any one of claims 2 to 9. The control unit includes:
When an instruction to execute the first calculation related to the first tax rate is input, the tax calculation based on the first tax rate is performed, and a third numerical value related to a result of the tax calculation based on the first tax rate is stored in the first memory. Remember
When an instruction to execute the first calculation related to the second tax rate is input, the tax calculation based on the second tax rate is performed, and a fourth numerical value related to the result of the tax calculation based on the second tax rate is stored in the first memory. Remember
In response to the input of the first read instruction, the read mode is set, and a total sum of the third numerical value and the fourth numerical value is displayed on the display unit.
A computer according to any one of claims 2 to 10. The control unit includes:
When an instruction to execute the first calculation relating to any one of the plurality of tax rates is input, the tax calculation is performed at the one of the tax rates, and the tax calculation at the one of the tax rates is performed. Storing a numerical value related to the result in the first memory;
In the state where the read mode is set,
In response to the input of the instruction to execute the function related to any one of the tax rates, displaying a total tax sum of numerical values indicating a result of the tax calculation based on at least one of the one or more tax rates,
A computer according to any one of claims 2 to 11. The control unit includes:
If a third read instruction different from the first read instruction is input while a numerical value indicating the result of the first calculation performed is displayed on the display unit, the third read instruction is stored in the second memory. The second numerical value is displayed on the display unit,
While the numerical value indicating the result of the executed second calculation is displayed on the display unit, when the third read instruction is input, the first numerical value stored in the first memory is displayed on the display unit. To be displayed in the
A computer according to any one of claims 1 to 12. The control unit includes:
According to the input of the switching instruction of the tax calculation mode, the calculation to be executed as the first calculation is switched to any of the calculation including tax and the calculation without tax,
When performing the tax-inclusive calculation as the first calculation, the first numerical value is stored in the first memory,
The computer according to any one of claims 1 to 13, wherein when performing the tax-excluded calculation as the first calculation, the first numerical value is not stored in the first memory. By computer of computer
In response to the input of the execution instruction of the first calculation, the first calculation using the numerical value is executed, the first numerical value related to the result of the first calculation executed is stored in the first memory, and displayed on the display unit. ,
In response to an input of a second calculation execution instruction different from the first calculation, a second calculation using a numerical value is executed, and a second numerical value related to the result of the executed second calculation is stored in a second memory. , And displayed on the display unit,
When a first read instruction is input while a numerical value indicating the result of the executed first calculation is displayed on the display unit, the first numerical value stored in the first memory is displayed on the display unit. To be displayed,
While the numerical value indicating the result of the executed second calculation is displayed on the display unit, when the first read instruction is input, the second numerical value stored in the second memory is displayed on the display unit. To be displayed in the
To make it work. A calculation method executed by a control unit of the computer,
In response to the input of the execution instruction of the first calculation, the first calculation using the numerical value is executed, the first numerical value related to the result of the first calculation executed is stored in the first memory, and displayed on the display unit. ,
In response to an input of a second calculation execution instruction different from the first calculation, a second calculation using a numerical value is executed, and a second numerical value related to the result of the executed second calculation is stored in a second memory. , And displayed on the display unit,
When a first read instruction is input while a numerical value indicating the result of the executed first calculation is displayed on the display unit, the first numerical value stored in the first memory is displayed on the display unit. To be displayed,
While the numerical value indicating the result of the executed second calculation is displayed on the display unit, when the first read instruction is input, the second numerical value stored in the second memory is displayed on the display unit. To be displayed in the
Method of calculation.