CASIO FX-790P (01) PDF Document

To ensure a long life for your CASIO FX-790P, please observe the following precautions:

• Since this computer consists of precision electronic parts, do not disassemble it. Also do not apply an impact to it by throwing or dropping it, or do not expose it to rapid temperature changes. In addition, do not store it in a place with high temperatures or high humidity, or in a dusty place. When the computer is utilized in low temperatures, sometimes the display response is slow or does not operate. When normal temperature conditions are restored, however, the computer operation will become normal.

• Special care should be taken not to damage the computer by bending. For example, do not carry it in your hip pocket.

• Please do not connect units other than the FA-5 and FP-12S to the connector portion.

• Use the SB-2 printer cable to connect to the FP-12S.

• Although the display sometimes becomes faint while the buzzer is sounding, it is not a malfunction. However, if the display becomes very faint, replace the batteries with new ones as soon as possible.

• Every two years, replace the batteries with new ones even if the computer is not used. Do not leave exhausted batteries inside it because trouble may occur due to battery leakage.

• Always keep the cap for the connector portion in place. Remove it only when peripherals are to be connected to the computer.

• If strong static electricity is applied to the computer, sometimes the memory content is changed, or key operation cannot be performed. To discharge static electricity accumulated in your body, touch a metallic substance like a door knob. If this occurs, remove the batteries, then replace them again.

• Always turn computer power off before connecting peripherals.

• To clean the computer, do not use volatile liquids such as benzine or thinner. Wipe it with a soft dry cloth, or a cloth dampened with a neutral detergent solution.

• Do not turn the power off during program execution or operation.

• Since the computer is made up of precision electronic parts, avoid dropping it while a program is being executed; otherwise the program execution may be stopped or the memory contents may be changed.

If a malfunction occurs with your CASIO FX-790P, first please read the owner’s manual again and check the power supply and the program for logic errors. If the issue persists, contact the store where the computer was purchased or a nearby dealer.

The main components of the CASIO FX-790P are identified as follows:

1. Display window

2. Alphabet keys

3. Shift key

4. Display contrast control

5. Function memory keys

6. Function keys

7. Statistical data input key

8. Numeral keys

9. Decimal point key

10. Exponent key

11. Execution key

12. Calculation command keys

13. Connector for peripherals

14. Power switch

15. Mode key

16. Assembly key

17. Memo/Search key

18. RESET button

Power Switch:

Slide the power switch up to turn power on and slide it down to turn power off.

Shift Key (Red [S] key):

Press this key for a one-key command (for inputting plural characters by pressing a single key) shown in red on the panel, for symbol display, or for input of a function. Press it once, and the SHIFT-IN mode will be selected and the “[S]” symbol will light up on the display. When it is pressed again or when another key is pressed, the SHIFT-IN mode will be canceled and the “[S]” symbol will go off.

The ten keys from 0 to 9 are used for number input. The [.] key is for decimal point input. The calculation command keys [+], [-], [*], and [/] need attention. These keys are for the four arithmetic operations (addition, subtraction, multiplication and division), but the x and ÷ keys of ordinary electronic calculators are replaced by * and / respectively. This is because of the need for common use with BASIC language.

When pressed directly, the [E] key serves as the exponent key. Press it before inputting the exponent (a certain power of 10). In the case of 1.23 x 10^4 for example, press [1][2][3][E][4]. When the exponent is negative, press the [-] key after the [E] key. For example, in the case of 7.41 x 10^-9, press [7][.][4][1][E][-][9].

The [(] and [)] keys are for inputting parentheses and the [↑] key for power calculations (for x^y).

Alphabet Keys and Space Key:

These keys are not found on ordinary electronic calculators. The 26 letters of the alphabet, the symbol keys (=, :, ;, .), and the space key (SPC) are arranged as on a typewriter. They are used to give commands or write programs. In addition, the 26-letter keys, A to Z, serve as “variable memory” (where numeric values, etc. are stored) individually.

Equal Key (=):

This key is not intended to obtain answers from calculations, but is used for conditional judgement in assignment statements (see page 107) or IF statements (see page 116). When it is pressed after the [SHIFT] key, the ≠ (not equal) symbol will be displayed.

Function Keys:

One of the features of this computer permits one-key input of functions as in scientific calculators. [x²] and [x³] are “square” and “cube” keys, respectively. [10^x] is a key for calculation of an exponential function (10^x) based on 10. When these keys are pressed after the [SHIFT] key, each performs the function shown above it.

Hexadecimal Key:

Press [SHIFT] [&H]. A hexadecimal number will be converted into a decimal number. Press a decimal number then [SHIFT] [HEX$]. The decimal number will be converted into a 4-digit hexadecimal number.

Engineering Key (ENG):

When this key is pressed, a calculation result or a numeric value displayed by a PRINT statement is converted into an exponent display. When this key is pressed repeatedly, the displayed exponent will decrease by 3 each time. The exponent can be increased by 3 each time by pressing [SHIFT] [ENG].

Answer Key (ANS):

When this key is pressed, the result of the immediately preceding calculation or the numeric value displayed by a PRINT statement is displayed.

Statistical Data Input Key (STAT):

Press this key after statistical data, and the data will be input to an exclusive memory area. When pressed following the [SHIFT] key, an SDEL function is performed to delete the input statistical data from the memory area.

Function Memory Keys ([IN], [OUT], [CALC]):

These keys are for the Function Memory. They are described in detail in Chapter 3 of the manual.

Cursor Movement Keys:

These keys are used when correcting displayed characters. The cursor (“_” blink in the display window) is moved right and left by these keys. Each time this key is pressed, the cursor moves by one character. When the key is held down, the cursor moves continuously through all of the characters present. When [SHIFT] [L.TOP] is pressed, the cursor moves to the left edge of the display (the beginning of the line) – LINE TOP function. When [SHIFT] [L.END] is pressed, the cursor moves to the right of the last input character (the end of the line) – LINE END function.

Insert/Delete Key (INS/DEL):

This is another convenient key for correcting displayed characters. When it is pressed directly, the characters following the one under which the cursor is blinking are moved to the right so that a space can be created for character insertion. The cursor itself does not move. When [SHIFT] [DEL] are pressed, the character under which the cursor is blinking is deleted and the characters on its right are moved to the left. The position of the cursor remains unchanged. Continuous insertion and deletions are possible by keeping [INS] and [SHIFT] [DEL] pressed respectively.

Break Key (BRK):

This is a powerful key capable of suspending various operations (manual operation, program execution, input/output with a cassette tape, output to the printer, program list output) and canceling errors. When it is pressed while display is out owing to AUTO POWER OFF, power is turned on again.

Clear Screen Key (CLS):

This clears the display and moves the cursor to the left edge of the display window.

Back Space Key (BS):

When this key is pressed, the character immediately to the left of the cursor is deleted while the characters immediately to the right of that character are moved to the left. Unlike the DEL key, the cursor moves to the left. The characters to the left of the cursor can be deleted continuously by keeping this button pressed.

Stop Key (STOP):

When pressed during program execution, this temporarily suspends program execution. When it is pressed while characters are being scrolled, the display is temporarily suspended. Execution is resumed when the [EXE] key is pressed.

When specifying a computer mode or an angle unit, use the [MODE] key in combination with a number key from 0 to 9.

• [MODE] [0]: This turns the key input buzzer sound on and off. When the buzzer is on, the “BUZZER” symbol lights up on the display.

• [MODE] [S]: The “RUN” symbol is displayed for manual and program calculations. (RUN mode)

• [MODE] [1]: The “WRT” symbol is displayed for program writing, checking and editing. (WRT mode)

• [MODE] [2]: The “TRACE ON” symbol is displayed for execution of tracing.

• [MODE] [3]: When the “TRACE ON” symbol is displayed, the execution trace mode is canceled and “TRACE ON” disappears.

• [MODE] [4]: The “DEG” symbol is displayed specifying “degrees” as the angle unit.

• [MODE] [5]: The “RAD” symbol is displayed specifying “radians” as the angle unit.

• [MODE] [6]: The “GRA” symbol is displayed specifying “grads” as the angle unit.

• [MODE] [7]: The “PRT ON” symbol is displayed and printer output is possible when a printer is connected to the computer.

• [MODE] [8]: When “PRT ON” is displayed, the printer output mode is canceled and “PRT ON” disappears.

• [MODE] [9]: The “MEMO IN” symbols light up to indicate that the MEMO IN mode is specified. This mode permits memo data input to the DATA BANK. To cancel this mode, press [MODE] [S].

The direct mode is specified immediately after the power is turned on. When a key is pressed in this mode, the character printed on the key is input. However, if the [EXT] key is pressed, the extension mode (the “EXT” symbol lights up) is specified, making it possible to input small letters or special symbols. The extension mode is effective for the upper half of the keyboard.

There are four modes for key functions:

a) Direct Mode: Just press the desired key. This inputs the primary character on the key (e.g., uppercase letters, numbers, basic operators).

b) Shift-in Mode: Press the [SHIFT] key first, then the desired key. This inputs the function or character printed in red above the key.

c) Direct Mode in the Extension Mode: Press the [EXT] key, then the desired key. This inputs the lowercase version of letters or alternate characters for other keys.

d) Shift-in Mode in the Extension Mode: Press the [EXT] key, then the [SHIFT] key, then the desired key. This inputs various special symbols.

Please note that each key has plural functions. When the [EXT] key is pressed again while the “EXT” symbol is on (extension mode), “EXT” disappears and the extension mode is canceled.

Display Contrast Control:

When the display is dark or faint, depending on the battery condition or display view angle, adjust it by moving the control located on the left side of the computer. To increase the display contrast, turn the control in the direction indicated by the arrow. To weaken the contrast, turn it in the opposite direction. If the contrast is still weak even after the control is at its highest-contrast position, the batteries have probably run down. If so, replace the batteries as soon as possible.

RESET Button:

This button is located below the power switch. If this button is pushed with a pointed object when the power is on, the computer will be reset to the state where no specification or no input is performed. This operation may be used when the computer is in locked state due to strong static electricity. Caution is required since all programs and data will be lost if pushed.

The power supply system for the CASIO FX-790P is divided into the main power supply (two CR2032 lithium batteries) and an auxiliary power supply for memory backup (one CR1220 lithium battery). To replace them, follow these steps:

Note: Be sure to replace the batteries every two years regardless of their use in order to prevent the chance of malfunction due to battery leakage.

1. Switch off the power supply and remove the rear panel after removing the three screws.

2. Remove the batteries.

– Main batteries: Remove the battery cover after loosening the screw (A).

– Auxiliary battery: Remove the battery cover after loosening the screw (B).

3. Remove the exhausted batteries. (They can be removed easily by tapping the battery compartment with its opening facing downward.)

4. Wipe the surfaces of new batteries well with a dry cloth before inserting them with the (+) side up.

5. Press the batteries down with the battery cover and slide the cover to close the battery compartment.

6. Replace the screws on the rear panel and switch on the power supply.

Important Notes on Batteries:

• The auxiliary battery is for memory backup. This battery remains in operation while the main battery is being replaced, thus preventing the program and data from vanishing. Bear in mind that if both the main and auxiliary batteries are removed at the same time, the program and data will vanish. If the main and auxiliary batteries must be replaced at the same time, press the reset button with a pointed object after switching on main frame power supply.

• Frequent use of the buzzer shortens battery life.

• When replacing the main batteries, be sure to replace both at the same time.

• Never throw batteries into a fire. It will be dangerous as they may burst.

• Care should be taken to ensure that battery polarity is correct.

• Keep batteries out of reach of children. If swallowed by accident, consult a doctor immediately.

This is an automatic power-saving function designed to prevent waste of power when a user forgets to switch off the power supply. The power supply is automatically cut off in 6 minutes upon completion of operation (except during program execution) or upon key-input waiting state following execution of an INPUT or PRINT statement. In such a case, power supply can be resumed by turning the power switch off and then on again or by pressing the [BRK] key.

Note: Even when the power supply is cut off, variable content, program content and DATA BANK content will be retained but mode specifications (“WRT”, “TRACE ON”, “PRT ON”, etc.) will be initialized immediately after turning the power on.

The standard free area (where programs and data can be written) is 7520 bytes on the CASIO FX-790P, but it can be expanded to a maximum of 15712 bytes by installing the optionally available RP-8 RAM pack.

Preparations:

In view of the possibility that the internal circuitry of the RAM pack might be destroyed by static electricity, touch a metallic substance like a door knob to discharge the static electricity accumulated in your body before you handle the pack.

Procedure:

1. Switch off the power supply. (Power switch -> OFF)

2. Loosen the three screws provided on the rear panel of the main frame and remove the panel.

3. Insert the RAM pack into its compartment and tighten the three screws. *Never touch the connector portion of the RAM pack or the PCB pad portion of the computer body.

4. Tighten the screws on the rear panel.

5. Switch on the power supply and press the RESET button with a pointed object.

Precautions:

• After installing or removing the RAM pack, be sure to press the reset button with a pointed object. If the reset button is not pressed, the memory contents may be changed or a meaningless display may be shown.

• Use care not to allow the connector portion of the pack or the PCB pad portion of the computer body to become dusty or dirty, and avoid getting fingerprints on them as this will cause poor contact.

• Be sure to place the removed pack in its case and store in a location where it is not subject to dust or dirt.

Performing a Calculation:

To perform a simple calculation, such as 123 + 456 = 579:

1. Press [CLS] to clear the display.

2. Press the keys according to the equation: [1][2][3][+][4][5][6]. The display will show “123+456_”.

3. Press [EXE] instead of [=] to find the answer. The display will show “579”.

Correcting Mistakes During Input:

If you make a mistake, you can correct it before pressing [EXE]. For example, if you meant to type 33*5+16 but typed 34*5+16:

1. You will see “34*5+16_” on the display.

2. Press the cursor movement key [◀] to bring the cursor to the wrong numeral (4).

3. The cursor and the ‘4’ will blink by turns. Press the right key [3].

4. The display now shows the corrected formula: “33*5+16_”.

5. Press [EXE] to get the answer.

You can also use the Back Space [BS] key. For example, if you meant to type 26×7+23 but typed 26×7+32:

1. The display shows “26*7+32_”.

2. Pressing the [BS] key will delete the character to the left of the cursor and move all characters to the right one space to the left. The display will show “26*7+3_”.

3. Press [BS] again to get “26*7+_”.

4. Input the correct numerals [2][3].

5. Press [EXE].

The alphabet keys are arranged in the same manner as on typewriters.

First write capitals.

Example: Input A, B, C, X, Y and Z.

1. First input A, B and C. Press [A][B][C]. Display: ABC_

2. Then input X, Y and Z. Press [X][Y][Z]. Display: ABCXYZ_

Next, insert a one-character space between ABC and XYZ.

1. Bring the cursor to the position of X using the cursor movement keys [◀]. The cursor and X blink by turns.

2. Make a one-character space. Press [INS]. Display: ABC_XYZ

To insert a space between characters in this manner, place the cursor where the space is to be inserted and press the [INS] key. When desiring to insert some spaces, keep this key pressed.

This computer is capable of displaying small letters and special characters in addition to numerals and capitals. For displaying these characters, use the extension mode. See page 9 of the manual for details.

In addition to the calculations as shown above, algebraic calculations using variables are possible with this computer. These calculations are convenient when a certain value is used repeatedly.

For example, to solve:

3x + 5 =

4x + 6 =

5x + 7 =

If the value of x in the above calculations is 123.456, it is troublesome to press the same numeral keys repeatedly. A labor-saving method for such calculations is algebraic calculation using a variable. Use variable X.

1. First assign 123.456 to the variable X. Press [X] [=] [1][2][3][.][4][5][6] [EXE]. The value is now assigned to X. Note: [=] here does not mean “equal,” but “assignment of the right side to the left side.”

2. Now start calculation.

– For 3x + 5, press [3][*][X][+][5] [EXE]. Result: 375.368

– For 4x + 6, press [4][*][X][+][6] [EXE]. Result: 499.824

– For 5x + 7, press [5][*][X][+][7] [EXE]. Result: 624.28

Repetitive calculations can be made as simple as this when a variable is used. This computer has 26 variables from A to Z, which makes possible storage of numerous values.

Calculations are subject to the rule of “priority sequence” (true algebraic logic) which requires that multiplication and division take precedence over addition and subtraction. This computer automatically judges the priority sequence. You simply input a numeric expression and the correct answer will be displayed.

Here is the priority sequence in a calculation:

1. Functions (sin, cos, tan, etc.)

2. Power (↑)

3. Multiplication (*), division (/)

4. Addition (+), subtraction (-)

Calculations are performed according to this priority sequence. When calculations happen to be equal in the priority sequence, priority is given to the calculation on the left. If there are parentheses, top priority should be given to the parenthesized calculation.

The CASIO FX-790P is capable of performing function calculations in addition to the four arithmetic operations. These functions can be used in a program, but manual operation is described here. The following functions are provided:

Note: In the case of asterisked functions, parameters must be parenthesized. Certain combinations or permutations may cause errors due to overflow during internal calculations.

“SET” is used for these specifications. You can use the following commands:

• Specification of number of significant digits: SET En (n = 0 ~ 9)

• Specification of number of decimal places: SET Fn (n = 0 ~ 9)

• Release of specification: SET N

*”SET E0″ used to specify the number of significant digits specifies 10 digits.

When a specification is made, the result is displayed by the number of specified digits. (The digit next to the last specified digit is rounded off.) The original value remains in the computer.

Example (significant digits):

To calculate 100 ÷ 6 with 4 significant digits:

Operation: [SHIFT] [SET] [E] [,] [4] [EXE], then [1][0][0] [/] [6] [EXE].

Display: 1.667E01

Example (decimal places):

To calculate 123 ÷ 7 with 2 decimal places:

Operation: [SHIFT] [SET] [F] [,] [2] [EXE], then [1][2][3] [/] [7] [EXE].

Display: 17.57

Example (release):

To calculate 1 ÷ 3 with the specification released:

Operation: [SHIFT] [SET] [N] [EXE], then [1] [/] [3] [EXE].

Display: 0.3333333333

Prior to start of a statistical calculation, clear the exclusive statistical memories. And input a statistical calculation. For this purpose, use the [STAT] key in the “RUN” mode.

Data Input Methods:

• One-variable data:

– Individual data: data [STAT]

– Plural identical data: data [;] frequency [STAT]

• Paired-variable data:

– Individual data: x data [,] y data [STAT]

– Plural identical data: x data [,] y data [;] frequency [STAT]

Example Operation:

1. Clear memories: Press [MODE] [S] (RUN mode). Then [SHIFT] [STAT] [CLEAR] [EXE]. Display shows “Ready P0” and then “STAT CLEAR”.

2. Input data: For a data point (x=1, y=2), press [1] [,] [2] [STAT]. Display shows “1, 2_” then “STAT 1,2”.

3. Input data with frequency: For 3 identical data points of (x=3, y=3), press [3] [,] [3] [;] [3] [STAT]. Display shows “STAT 3,3:3”.

4. Delete data: To delete the data “1, 2”, press [1] [,] [2] [SHIFT] [SDEL]. Display shows “SDEL 1,2”.

Notes:

*1. y data can be omitted by using “x data (; frequency) [STAT]”. In such a case y’s values are the same as the previous ones. ([; frequency] can be omitted.)

*2. When x data can be omitted by using “, y data (; frequency) [STAT]”, x values are the same as the previous ones. ([; frequency] can be omitted.)

*3. When [SHIFT] [SDEL] are pressed instead of [STAT] after data input, the data is deleted from the statistical memory.

* Input statistical data are stored even after power is off unless the above deletion is made or the STAT CLEAR command is executed by pressing [SHIFT] [STAT] [CLEAR] [EXE]. Therefore, when inputting statistical data anew, be sure to execute the STAT CLEAR command in advance so as to clear statistical memories.

* When “frequency” is omitted, frequency is regarded as 1.

The CASIO FX-790P can calculate a variety of statistics. The values and their corresponding formulas are listed below:

To view these statistics, use the STAT LIST command. STAT LIST (or STAT LIST 0) outputs all statistics. STAT LIST 1 is for one-variable statistics, and STAT LIST 2 is for paired-variable statistics. EOX and EOY are treated as functions and can be calculated in the same way as ordinary numerical functions.

The “Function Memory” permits easy calculations by simply assigning numeric values to the variable as long as the formula is stored in advance. The following keys are used:

• [IN]: Stores the contents currently written.

• [OUT]: Displays the stored content.

• [CALC]: If the stored content is a formula, the desired numeric value will be assigned to the used variables and the calculated result will be displayed.

Example: Obtain the value of y for each of the values assigned to x when y = 3.43 Cos x. (Calculate in three decimal places.)

1. First specify the angle unit and number of decimal places.

– Press [MODE] [4] to set the angle unit to “DEG”.

– Press [SHIFT] [SET] [F] [,] [3] [EXE] to set three decimal places.

2. Next, input a formula, and press the [IN] key to store it.

– Type [Y] [=] [3] [.] [4] [3] [*] [COS] [X]. Then press [IN]. The formula is now stored.

3. Press the [OUT] key to confirm that the formula has been stored. The display will show “Y=3.43*COSX_”.

4. Then, start calculating by pressing the [CALC] key.

– Press [CALC]. Display: X ?

– Enter [8] [EXE]. Display: Y= 3.397

– Press [CALC]. Display: X ?

– Enter [15] [EXE]. Display: Y= 3.313

– Continue this process for all values of X.

If you add a semicolon (;) at the end of the formula when storing, the formula can be executed repeatedly by pressing the [EXE] key instead of the [CALC] key each time.

Here are some points requiring care in using the “Function Memory”:

1. Character string of up to 62 characters can be stored with the [IN] key. The 63rd character and after will be discarded. Since spaces included in the commands and functions input with the one-key command will be counted as characters, delete these spaces with [SHIFT] [DEL] if there are too many characters.

2. The stored contents will be retained even if power is turned off or if Auto Power off function is activated.

3. The stored data will be cleared if assembly is executed by pressing the [A] key after pressing the [Asmbl] key.

4. Error will occur when [CALC] is pressed if the stored content is other than a formula.

5. The functions in the formula must be numeric functions.

6. The variables in the formula must be numeric variables A ~ Z.

7. If an exclusive character variable $ is included in the formula, the content of the variable $ will be used. (e.g. VAL($)*A, etc.)

Writing a Program:

1. Press [MODE] [1] to enter WRT (Write) mode. The symbol “WRT” should appear in the upper part of the display. The display will show the currently selected program area (e.g., P0) and the remaining free memory in bytes.

2. You can switch between program areas (P0-P9) by pressing [SHIFT] and a number key [0]-[9].

3. It’s good practice to start with a `NEW ALL` command to erase all existing programs and variables. Type `NEWALL` and press [EXE].

4. Enter your program line by line. Each line must start with a line number (1 to 9999) followed by a statement. Press [EXE] at the end of each line to store it.

Example Program:

10 INPUT “X=”,X

20 Y=2*X↑2+91*X+125

30 PRINT “Y=”;Y

40 GOTO 10

50 END

Correcting Program Errors:

• Before pressing [EXE]: Use the cursor movement keys, [BS], [INS], or [DEL] to correct the line, just like editing a calculation.

• After pressing [EXE]: To edit a stored line, use the `LIST ` command in WRT mode to display the line. Then, edit it and press [EXE] to save the changes.

Adding and Deleting Lines:

• To add a line: Simply type a new line number and the statement, then press [EXE].

• If a line is input with an already used line number: The previous line will be erased and the new one will have priority.

• To delete a line: Enter the line number to be deleted after clearing the display and press [EXE].

Executing a Program:

1. To execute a stored program, specify the RUN mode by pressing [MODE] [S]. The display will then show “Ready P0” (or the currently specified program area).

2. Type `RUN` and press [EXE]. The program starts.

3. To pause execution, press the [STOP] key. “STOP” will appear at the upper right of the display. To resume, press [EXE].

4. To terminate execution, press the [BRK] key. The display will then return to the initial state of the RUN mode.

The CASIO FX-790P provides several types of variables for use in calculations and programming:

• Simple Variables: Twenty-six variables named A to Z are provided as a standard feature. All variables are for numeric values, but can be made character variables by adding a dollar sign ($) after the variable name. In addition, there is the exclusive character variable $.

• Array Variables: This computer is capable of array variable declarations by DIM statements and array declarations by DEFM statements. It is possible to use array variables of up to three dimensions. A maximum of up to eight array variables can be used simultaneously with a DIM statement.

• Variable Capacity: The numeric variable will store numeric values of up to 12 digits (for a mantissa and 2 digits for an exponent) and the character variable will store character string of up to 7 characters. The exclusive character variable $ will store character string of up to 62 characters.

Although 26 variables (A to Z) are provided as a standard feature of the computer, additional variables can be used by variable expansion. The variables can be expanded by using the DEFM command and specifying with the format “DEFM Number expanded (numeric expression)”.

Example: To add 20 variables for a total of 46, operate as shown below in the RUN or WRT mode:

Type `DEFM 20` and press [EXE].

The display will show: `A..Z:26 DEFM:20`

The newly expanded variables are used as array variables following variable Z. The relation of each variable will be as shown below (For FX-785P):

A(26) = B(25) = … = Y(2) = Z(1)

A(27) = B(26) = … = Y(3) = Z(2)

…

A(197) = B(196) = … = Y(173) = Z(172)

Notes:

• If the variables are expanded, that specification will be saved even when the power is turned off. Execute DEFM 0 to return to the standard 26 variables.

• The variables will return to the standard 26 if `NEW ALL` is operated in the WRT mode or if changed over to the DIM mode.

• If the number of free bytes used to expand the variables is specified in excess of the remaining free area, a MEMORY OVER error (Error 1) will occur to protect the stored programs and data.

The remaining capacity of free area will decrease by 8 bytes for each expanded variable so care will be required since there may be insufficient space to create a program if expanded excessively. The table below shows the relations between the number of variables and the maximum capacity of the free area. This shows that a large number of variables can be used with the RP-8 RAM expansion pack.

The maximum capacity of the free area used for programs and DATA BANK is 7520 bytes for the CASIO FX-790P. When the RAM expansion pack is used, the free area will be 15712 bytes. The free area decreases as programs and data are written. The number of bytes required to write programs and data are calculated as shown below.

• Line number: Two bytes for one regardless of the number between 1 to 9999.

• Command: One byte for one command.

• Function: One byte for one function.

• Character: One byte for one character (a space will also be considered a character.)

• [EXE] key: One byte will be required when the [EXE] key is pressed at the end of a line.

• Array Variable (DIM): If an array variable is declared with a DIM statement, eight bytes will be required for one array element.

• Expanded Variable (DEFM): If the number of variables is expanded with the DEFM statement, eight bytes will be required for each variable expanded.

When using many array variables or when setting up a long program, it will be necessary to consider the length of the program according to the above calculations and to trim any unnecessary portions.

If an error occurs, specify the WRT mode by pressing [MODE] [1] after releasing the error by pressing the [BRK] key and correct by calling the error line with the LIST command.

If the desired result cannot be obtained without any error message displayed, there is a “bug” that does not become an error somewhere in the program. In this case, debugging is carried out while executing the program.

Debugging with the STOP Command:

Since the program execution will pause if the STOP command is written immediately after the line containing the variable to be checked, display and check the contents of the variable by entering variable to be checked followed by [EXE]. To continue executing the program, press [EXE].

Debugging with the TRACE Mode:

Press [MODE] [2] and “TRACE ON” will be displayed. This mode is called the TRACE mode. If a program is executed in the TRACE mode, there will be a pause after each line (after each statement when using multistatements). Press [EXE] to advance to the next execution. The TRACE mode is used to find the bug by tracing the flow of the program. Pressing [MODE] [3] causes “TRACE ON” to disappear and cancel the TRACE mode.

You can use the optional FA-5 cassette interface to store programs on a cassette tape.

1. Connect the devices: Turn off the power supply of the computer. Remove the connector covers of the FA-5 and the computer and connect them. Connect the microphone terminal (white plug) to the “MIC” (or “LINE IN”) terminal of the tape recorder and the earphone terminal (black plug) to the “EAR” (or “MONITOR” or “LINE OUT”) terminal.

2. Operation of the Tape Recorder:

– In the case of SAVE and PUT, the command is executed with the tape recorder set to “RECORD”.

– In the case of LOAD and GET, the tape recorder is set to “PLAYBACK” and started after first executing the command.

Program Storing and Loading Commands:

• SAVE Command: Use `SAVE` or `SAVE “filename”`. `SAVE` stores the program in the currently specified program area. Up to 8 characters can be used for a file name.

• SAVE ALL Command: Use `SAVE ALL` or `SAVE ALL “filename”`. `SAVE ALL` can simultaneously store programs located in all program areas.

• LOAD and LOAD ALL Commands: These commands are used to load programs from a cassette tape to the computer. The proper use of these commands depends on whether programs were stored by SAVE or SAVE ALL.

Precautions:

Sometimes a program cannot be stored or loaded smoothly. If this happens, check the following items:

• “Error 9” is displayed during storing: Check if the computer is properly connected to the FA-5.

• “Error 9” is displayed during loading: Check if the tape is stretched (replace it), if the head of the tape recorder is dirty (clean it), or if the tone control is set to medium.

• No error is displayed but loading is attempted without success: If the tape recorder output volume is low, increase the volume near MAX. Check if the output standard of the tape recorder is in accordance with that of the FA-5.

Items marked with “O” can be loaded; those marked with “X” cannot be loaded. File names must be identical.

When programs are loaded by LOAD or LOAD ALL, a display depending on the storing format appears:

Storing and Loading of Data in the DATA BANK:

All the data in the DATA BANK can be stored on a cassette tape at once by using “SAVE #”.

• SAVE#: `SAVE# “File name”`. Up to 8 characters can be placed inside ” ” for a file name.

• LOAD#: `LOAD# “File name”`. This command is used to load data into the DATA BANK from a tape. The previous data are erased when new data are loaded. However, if `,M` is specified at the end of the LOAD# command, the data from the tape are loaded following the previously stored data left intact.

Data Storing and Loading (Variables):

A program always has data; it is troublesome to enter these data from the keyboard each time. You can store data on a tape and load it again using the PUT and GET commands.

• PUT: `PUT “File name” Variable 1, Variable 2`. To store data on a tape, “PUT” is used. Variables are specified in a PUT command. A file name can also be specified (up to 8 characters).

– Example: `PUT $,A,M` stores the contents of the exclusive character variable ($) and 13 variables from A to M.

– Example: `PUT “DATA” A(*)` stores the contents of array variable A(10) with the file name “DATA” in the DIM mode.

• GET: `GET “File name” Variable 1, Variable 2`. “GET” is used to load data from a tape to the computer. Variables are specified in a GET command. A file name can also be specified.

– Example: `GET $,X,Z` loads data to the exclusive character variable ($) and 3 variables from X to Z.

An exclusive mini printer (FP-12S) is used for printing out programs, data and calculation results on paper. An exclusive cable (SB-2) is also optionally available to connect the mini printer to the computer. Connect one end of the cable (SB-2) to the connector of the computer and the other end to the connector of the mini printer. Although the mini printer is not provided with a power switch, the paper can be fed by pushing the button on printer with the computer’s power switch on.

Printing is carried out by key operation in the PRINT mode (“PRT ON” displayed). The PRINT mode can be specified by pressing [MODE] [7] and can be canceled by pressing [MODE] [8].

What You Can Print:

1. Printing Program Contents: Execute the LIST command after pressing [MODE] [7] in the RUN mode. If it is desired to print out the contents of all program areas from P0 to P9, enter LIST ALL [EXE]. After completing printing, do not forget to press [MODE] [8] to cancel the PRINT mode.

2. Printing Out Calculation Results: When desiring to print calculation results, specify the PRINT mode by pressing [MODE] [7] or by writing “MODE 7” in the program. It will be more convenient to write “MODE 7” in the program if only certain parts are to be printed. *When writing in the program, enter M O D E instead of pressing the [MODE] key.

3. Printing Data in the DATA BANK: To print the memo data stored in the DATA BANK, execute the LIST# command after pressing [MODE] [7] in the RUN mode. *After printing is finished, cancel the PRINT mode by pressing [MODE] [8].

4. Printing the Assembler Program: To print the source program in the source area, execute the LIST* command after pressing [MODE] [7] in the RUN mode. If LIST*1 is executed the output will be in assembler format and, if LIST*0 or simply LIST*, the output will be with a record number attached.

Programs prepared for the PB-100, PB-300, FX-700P and FX-802P can be utilized with this computer. In spite of these different points, a program prepared by the PB-100/PB-300/FX-700P/FX-802P can be fundamentally utilized with this computer. However, it is better that programs be rewritten for this computer so that it can be easily used or can be easily reconsidered later.

Key differences to be aware of include:

Additional Commands on this computer: PASS, BEEP, READ, DATA, RESTORE, ON ~ GOTO, ON ~ GOSUB, REM, DIM, ERASE, LIST V, LIST*, LOAD*, SAVE*, NEW*.

Additional Functions on this computer: DEG, DMS$, STR$.

Modified Commands:

Modified Functions:

Example Modifications:

• Change “VAC” on line 10 to “CLEAR”.

• Change “;” on lines 40 to 70 to “THEN”.

• If variable expansion is necessary, write the DEFM command at the beginning of the program.

PRECAUTIONS:

• When transferring a program prepared with this computer to other CASIO’s computers, a DIM, ERASE, READ#, WRITE# or RESTORE# command must not exist in the program. In the case of PB-100 series, use KEY and MID in place of KEY$ and MID$.

• A program created with other CASIO’s computers may not be correctly executed in this computer.

• If a numeric expression is used at the IF ~ THEN branch destination, an error occurs. In this case, correct it to IF ~ THEN GOTO branch destination.

The DATA BANK function allows the computer to be used as an “electronic memo pad” for storing and retrieving data like names and telephone numbers.

1. Specifying the MEMO IN Mode:

To input and store data, first specify the MEMO IN mode. Pressing [MODE] [9] will specify the MEMO IN mode and the display will appear as shown below. The symbol “MEMO IN” at the upper center shows the mode is specified. The number at the upper right is the record number. The blinking cursor at the left end indicates the computer is in the key-input waiting state.

2. Inputting Data:

Start with entering the data. Separate the name and telephone number by inserting a “,” (comma) between them.

Example: To enter “BROWN, 03-021-1234”

– Type `BROWN`

– Press [,]

– Type `03-021-1234`

– Press [EXE]. The data will be stored in the DATA BANK as memo data of record 1.

Press the [EXE] key once more. The display will be cleared and the record number will change to 2. The blinking cursor indicates that the computer is in the key-input waiting state.

3. Displaying the Data Contents:

To confirm the input data, display the data contents. Specify the RUN mode by pressing [MODE] [S]. Use the `LIST#` command to display the entire contents of the DATA BANK. The data in each record will be displayed successively at approximately 1.5 sec. intervals together with the record number.

Press the [STOP] key to stop the display temporarily for checking the contents. Press the [EXE] key to resume the following display.

Correcting Data:

In MEMO IN mode, you can correct data. Use the [EXE] key to advance to the record you wish to correct. Once the data is displayed, press the cursor movement keys [◀] or [▶] to specify the EDIT mode. Move the cursor to the position to be corrected, make the correction, and press [EXE] to store the corrected data.

Retrieving (Searching) Data:

Data retrieval can be performed directly by pressing the [MEMO/SEARCH] key in RUN mode.

• Simple Search: Pressing the [MEMO/SEARCH] key will display the data in Record 1. Pressing it again will display the next part of the same record (if it’s long). Pressing it again displays the next record. This continues sequentially through the data.

• Quick Search: Pressing the [EXE] key advances through the records one by one.

• Backward Search: Use [SHIFT] [MEMO/SEARCH] to display a previous record.

• Conditional Search: For example, to find a name starting with “S”, press [S] then [MEMO/SEARCH]. The first record starting with “S” will be displayed. You can use longer character strings for more specific searches.

Erasing Data:

• To Erase Part of a Record: Display the desired data in the MEMO IN mode and specify the EDIT mode by pressing a cursor movement key. Move the cursor to the character that you wish to erase. Press [SHIFT] [DEL] to erase the character. After erasing unnecessary characters, be sure to press the [EXE] key.

• To Erase All Data in a Record: Display the desired record in the MEMO IN mode and specify the EDIT mode. Then clear the display by pressing the [CLS] key. And press the [EXE] key. All data in that record will be erased and the current record number will be automatically assigned to the next record.

• To erase all data stored in the DATA BANK: Execute the `NEW#` command in the WRT mode ([MODE] [1]).

Adding and Inserting Data:

• Adding Data: In MEMO IN mode, specifying a record number beyond the last stored record will allow you to add a new record.

• Inserting Data: To insert new data between stored records, first display the record where the new data will be inserted. Then, input the new data to be inserted and press [SHIFT] [EXE]. The new data will be stored, and all subsequent records will be shifted down by one.

A practical method of using the DATA BANK function is to use it in combination with the Function Memory. Store formulas and equations in the DATA BANK and press the [MEMO/SEARCH] key to call the desired formula or equation. And calculate by storing the retrieved formula in the Function Memory by pressing the [IN] key.

Assume the following formulas and equation are stored in the DATA BANK:

1 QUADRATIC EQUATION

2 X=(-B+SQR(B↑2-4*A*C))/(2*A):X=(-B-SQR(B↑2-4*A*C))/(2*A)

3 HERON

4 S”=(A+B+C)/2:S=SQR(S*(S-A)*(S-B)*(S-C))

To calculate the root of the quadratic equation:

1. Press [MEMO/SEARCH] to search the quadratic equation. “QUADRATIC EQUATION” will be displayed.

2. After confirming the name, press the [EXE] key and the calculation formula is displayed. `X=(-B+SQR(B↑2-4*A*C))/(2…`

3. Then store the calculation formula in the Function Memory. Press [IN].

4. Now you are ready to calculate. Input values for A, B, and C as prompted after pressing [CALC].

Note: When storing a formula name and calculating formula in the DATA BANK, do not store them in one record. Store the calculating formula in the record following the record in which the formula name is stored.

Type: FX-790P

Fundamental Calculation Functions: Negative numbers, exponents, parenthetical addition, subtraction, multiplication and division (with priority sequence judgement function — true algebraic logic).

Built-in Functions: Trigonometric/inverse trigonometric functions (angle units degrees/radians/grads), hyperbolic/inverse hyperbolic functions, logarithmic/exponential functions, square roots, cube roots, powers, conversion to integer, deletion of integer portion, absolute values, signs, designation of number of significant digits, designation of number of decimal places, decimal ↔ sexagesimal conversions, decimal ↔ hexadecimal conversions, rectangular ↔ polar coordinate transformations, factorials, permutations, combinations, rounding, random number generations, π.

Statistical Calculation Functions: Number of data, sum of x, sum of y, sum of x², sum of y², sum of x·y, mean of x, mean of y, standard deviation of x (2 types), standard deviation of y (2 types), linear regression constant term, linear regression coefficient, correlation coefficient, estimated value of x, estimated value of y.

Commands: INPUT, PRINT, GOTO, ON ~ GOTO, FOR ~ TO ~ STEP ~ NEXT, IF ~ THEN, GOSUB, ON ~ GOSUB, RETURN, READ, DATA, RESTORE, STOP, END, RUN, LIST, LIST V, LIST ALL, MODE, SET, CLEAR, NEW, NEW ALL, ERASE, DIM, DEFM, PASS, REM, BEEP, LET, SAVE, SAVE ALL, LOAD, LOAD ALL, PUT, GET, VERIFY, NEW#, LIST#, LOAD#, SAVE#, READ#, WRITE#, RESTORE#, NEW*, LIST*, LOAD*, SAVE*, STAT, STAT CLEAR, STAT LIST.

Program Functions: DMSS, KEY$, CSR, LEN, MID$, STR$, VAL, HEX$.

Calculation Range: ±1 x 10⁻⁹⁹ ~ ±9.999999999 x 10⁹⁹ and 0. Internal operation uses 12-digit mantissa.

Program System: Stored system

Program Language: BASIC

RAM Capacity: FX-790P: Standard 7,520 bytes (system area: 672 bytes) (15,712 bytes with the RP-8 RAM expansion pack)

Number of Program Areas: Maximum 10 (P0 through P9)

Number of Variables: 26 fixed variables, exclusive character variable and array variables.

Number of Stacks: Subroutine: 8 levels; FOR ~ NEXT loop: 4 levels; Numeric values: 6 levels; Operators: 12 levels

Number of Display Digits: 10-digit mantissa (including minus sign) and 2-digit exponent

Display Contents: BUZZER, EXT, [S], RUN, WRT, DEG, RAD, GRA, DEFM, [ASMBL], MEMO, [SOURCE], [IN], [EDIT], TRACE ON, PRT ON, STOP

Display Elements: 24-digit dot matrix liquid crystal display

Main Components: C-MOS VLSI and others

Power Supply: 2 lithium batteries (CR2032) for the mainframe; 1 lithium battery (CR1220) for memory backup

Power Consumption: Maximum 0.07W

Battery Life: 1) Continuous program execution: Approx. 85 hours; 2) Continuous display of 5555555555 at 20°C (68°F): Approx. 200 hours; 5.5 months when unit is used 1 hour per day.

Auto Power-off: Approximately 6 minutes

Ambient Temperature Range: 0°C to 40°C (32°F to 104°F)

Dimensions: Folded: 18H x 142W x 71D mm; Unfolded: 9H x 142W x 142D mm

Weight: 165 g (5.8 oz) including batteries.