Casio NP20 User Manual

ALGEBRA FX 2.0  
User’s Guide  
E
BEFORE USING THE CALCULATOR  
FOR THE FIRST TIME...  
This calculator does not contain any main batteries when you purchase it. Be sure to  
perform the following procedure to load batteries, reset the calculator, and adjust the  
contrast before trying to use the calculator for the first time.  
1. Making sure that you do not accidently press the o key, slide the case onto the  
calculator and then turn the calculator over. Remove the back cover from the calculator  
by pulling with your finger at the point marked 1.  
1
P
2. Load the four batteries that come with calculator.  
• Make sure that the positive (+) and negative (–) ends of the batteries are facing cor-  
rectly.  
BACK UP  
3. Remove the insulating sheet at the location marked “BACK UP” by pulling in the direc-  
tion indicated by the arrow.  
BACK UP  
4. Replace the back cover, making sure that its tabs enter the holes marked 2 and turn  
the calculator front side up. The calculator should automatically turn on power and  
perform the memory reset operation.  
2
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5. Press m.  
If the Main Menu shown to the right is not on the display,  
press the P button on the back of the calculator to  
perform memory reset.  
P button  
6. Use the cursor keys (f, c, d, e) to select the SYSTEM icon and press  
w, then press 2(  
) to display the contrast adjustment screen.  
7. Adjust the contrast.  
• The e cursor key makes display contrast darker.  
• The d cursor key makes display contrast lighter.  
1(INIT) returns display contrast to its initial default.  
8. To exit display contrast adjustment, press m.  
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Quick-Start  
Turning Power On And Off  
Using Modes  
Basic Calculations  
Replay Feature  
Fraction Calculations  
Exponents  
Graph Functions  
Dual Graph  
Box Zoom  
Dynamic Graph  
Table Function  
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1
Quick-Start  
Quick-Start  
Welcome to the world of graphing calculators.  
Quick-Start is not a complete tutorial, but it takes you through many of the most common  
functions, from turning the power on, and on to graphing complex equations. When  
you’re done, you’ll have mastered the basic operation of this calculator and will be ready  
to proceed with the rest of this user’s guide to learn the entire spectrum of functions  
available.  
Each step of the examples in Quick-Start is shown graphically to help you follow along  
quickly and easily. When you need to enter the number 57, for example, we’ve indi-  
cated it as follows:  
Press fh  
Whenever necessary, we’ve included samples of what your screen should look like.  
If you find that your screen doesn’t match the sample, you can restart from the begin-  
ning by pressing the “All Clear” button o.  
TURNING POWER ON AND OFF  
To tur n power on, press o.  
OFF  
o
To turn power off, press !  
.
Calculator power turns off automatically if you do not perform any operation within the  
Auto Power Off trigger time you specify. You can specify either six minutes or 60  
minutes as the trigger time.  
USING MODES  
This calculator makes it easy to perform a wide range of calculations by simply  
selecting the appropriate mode. Before getting into actual calculations and operation  
examples, let’s take a look at how to navigate around the modes.  
To select the RUN MAT Mode  
1. Press m to display the Main Menu.  
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2
Quick-Start  
2. Use defc to highlight RUN MAT  
and then press w.  
This is the initial screen of the RUN MAT Mode,  
where you can perform manual calculations,  
matrix calculations, and run programs.  
BASIC CALCULATIONS  
With manual calculations, you input formulas from left to right, just as they are written  
on paper. With formulas that include mixed arithmetic operators and parentheses, the  
calculator automatically applies true algebraic logic to calculate the result.  
Example: 15 × 3 + 61  
1. Press o to clear the calculator.  
2. Pressbf*d+gbw.  
Parentheses Calculations  
Example: 15 × (3 + 61)  
1. Pressbf*(d  
+gb)w.  
Built-In Functions  
This calculator includes a number of built-in scientific functions, including trigonometric  
and logarithmic functions.  
Example: 25 × sin 45˚  
Important!  
Be sure that you specify Deg (degrees) as the angle unit before you try this  
example.  
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3
Quick-Start  
SET UP  
3 to display the SET UP screen.  
1. Pressu  
2. Presscccc1(Deg) to specify  
degrees as the angle unit.  
3. Pressi to clear the menu.  
4. Presso to clear the unit.  
5. Presscf*sefw.  
REPLAY FEATURE  
With the replay feature, simply press dor eto recall the last calculation that  
was performed so you can make changes or re-execute it as it is.  
Example: To change the calculation in the last example from (25 × sin 45˚) to  
(25 × sin 55˚)  
1. Press d to display the last calculation.  
REPLAY  
2. Press d twice to move the cursor (t) to 4.  
3. Press D to delete 4.  
4. Press f.  
5. Press w to execute the calculation again.  
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4
Quick-Start  
FRACTION CALCULATIONS  
You can use the $ key to input fractions into calculations. The symbol “ { ” is used  
to separate the various parts of a fraction.  
37  
Example: 1 15  
/
+
/
9
16  
1. Presso.  
2. Pressb$bf$  
bg+dh$  
jw.  
Indicates 6 7/144  
Converting a Mixed Fraction to an Improper Fraction  
d/c  
$
While a mixed fraction is shown on the display, press !  
to convert it to an  
improper fraction.  
d/c  
$
Press !  
again to convert back to a mixed fraction.  
Converting a Fraction to Its Decimal Equivalent  
While a fraction is shown on the display, press $to convert it to its decimal  
equivalent.  
Press $again to convert back to a fraction.  
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5
Quick-Start  
EXPONENTS  
Example: 1250 × 2.065  
1. Presso.  
2. Pressbcfa*c.ag.  
3. PressM and the ^ indicator appears on the display.  
4. Pressf. The ^5 on the display indicates that 5 is an exponent.  
5. Pressw.  
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Quick-Start  
GRAPH FUNCTIONS  
The graphing capabilities of this calculator makes it possible to draw complex graphs  
using either rectangular coordinates (horizontal axis: x ; vertical axis: y) or polar  
coordinates (angle: θ ; distance from origin: r).  
All of the following graphing examples are performed starting from the calculator setup  
in effect immediately following a reset operation.  
Example 1: To graphY = X(X + 1)(X – 2)  
1. Press m.  
2. Use defc to highlight  
GRPH TBL, and then press w.  
3. Input the formula.  
v(v+b)  
(v-c)w  
4. Press 5(DRAW) or w to draw the graph.  
Example 2: To determine the roots of Y = X(X + 1)(X – 2)  
1. Press 4(G-SLV) to display the pull-up menu.  
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Quick-Start  
2. Press b(Root).  
Press e for other roots.  
Example 3: Determine the area bounded by the origin and the X = –1 root obtained  
for Y = X(X + 1)(X – 2)  
1. Press i4(G-SLV)c.  
2. Press i(dx).  
3. Use dto move the pointer to the location where  
X = –1, and then press w. Next, use e to  
move the pointer to the location where X = 0, and  
then press  
to input the integration range,  
w
which becomes shaded on the display.  
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Quick-Start  
DUAL GRAPH  
With this function you can split the display between two areas and display two graphs  
on the same screen.  
Example: To draw the following two graphs and determine the points of intersection  
Y1 = X(X + 1)(X – 2)  
Y2 = X + 1.2  
SET UP  
3
1. Press u  
ccc2(G+G)  
to specify “G+G” for the Dual Screen setting.  
2. Press i, and then input the two functions.  
v(v+b)  
(v-c)w  
v+b.cw  
3. Press 5(DRAW) or w to draw the graphs.  
BOX ZOOM  
Use the Box Zoom function to specify areas of a graph for enlargement.  
1. Press 2(ZOOM) b(Box).  
2. Use d e fc to move the pointer  
to one corner of the area you want to specify and  
then press  
.
w
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9
Quick-Start  
3. Use de fc to move the pointer  
again. As you do, a box appears on the display.  
Move the pointer so the box encloses the area  
you want to enlarge.  
4. Press w, and the enlarged area appears in the  
inactive (right side) screen.  
DYNAMIC GRAPH  
Dynamic Graph lets you see how the shape of a graph is affected as the value  
assigned to one of the coefficients of its function changes.  
Example: To draw graphs as the value of coefficient A in the following function changes  
from 1 to 3  
Y = AX2  
1. Press m.  
2. Use d e fc to highlight DYNA,  
and then press w.  
3. Input the formula.  
A
v
a
vxw  
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10  
Quick-Start  
4. Press 4(VAR) bw to assign an initial value  
of 1 to coefficient A.  
5. Press 2(RANG) bwdwb  
wto specify the range and increment of change  
in coefficient A.  
6. Press i.  
7. Press 6(DYNA) to start Dynamic Graph drawing.  
The graphs are drawn 10 times.  
↓↑  
↓↑  
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Quick-Start  
TABLE FUNCTION  
The Table Function makes it possible to generate a table of solutions as different  
values are assigned to the variables of a function.  
Example: To create a number table for the following function  
Y = X (X+1) (X–2)  
1. Press m.  
2. Use defc to highlight  
GRPH TBL, and then press w.  
3. Input the formula.  
v(v+b)  
(v-c)w  
4. Press 6(g)5(TABL) to generate the number  
table.  
To learn all about the many powerful features of this calculator, read on and explore!  
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Handling Precautions  
Your calculator is made up of precision components. Never try to take it apart.  
• Avoid dropping your calculator and subjecting it to strong impact.  
• Do not store the calculator or leave it in areas exposed to high temperatures or humidity, or  
large amounts of dust. When exposed to low temperatures, the calculator may require more time  
to display results and may even fail to operate. Correct operation will resume once the calculator  
is brought back to normal temperature.  
• The display will go blank and keys will not operate during calculations. When you are operating  
the keyboard, be sure to watch the display to make sure that all your key operations are being  
performed correctly.  
• Replace the main batteries once every 2 years regardless of how much the calculator is used  
during that period. Never leave dead batteries in the battery compartment. They can leak and  
damage the unit.  
• Keep batteries out of the reach of small children. If swallowed, consult a physician immediately.  
• Avoid using volatile liquids such as thinner or benzine to clean the unit. Wipe it with a soft, dry  
cloth, or with a cloth that has been moistened with a solution of water and a neutral detergent  
and wrung out.  
• Always be gentle when wiping dust off the display to avoid scratching it.  
• In no event will the manufacturer and its suppliers be liable to you or any other person for any  
damages, expenses, lost profits, lost savings or any other damages arising out of loss of data  
and/or formulas arising out of malfunction, repairs, or battery replacement. It is up to you to  
prepare physical records of data to protect against such data loss.  
• Never dispose of batteries, the liquid crystal panel, or other components by burning them.  
• When the “Low Main Batteries!” message or the “Low Backup battery!” message appears on the  
display, replace the main power supply batteries or the back up battery as soon as possible.  
• Be sure that the power switch is set to OFF when replacing batteries.  
• If the calculator is exposed to a strong electrostatic charge, its memory contents may be  
damaged or the keys may stop working. In such a case, perform the Reset operation to clear the  
memory and restore normal key operation.  
• If the calculator stops operating correctly for some reason, use a thin, pointed object to press  
the P button on the back of the calculator. Note, however, that this clears all the data in  
calculator memory.  
• Note that strong vibration or impact during program execution can cause execution to stop or  
can damage the calculator’s memory contents.  
• Using the calculator near a television or radio can cause interference with TV or radio reception.  
• Before assuming malfunction of the unit, be sure to carefully reread this user’s guide and ensure  
that the problem is not due to insufficient battery power, programming or operational errors.  
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Be sure to keep physical records of all important data!  
Low battery power or incorrect replacement of the batteries that power the unit can cause the  
data stored in memory to be corrupted or even lost entirely. Stored data can also be affected by  
strong electrostatic charge or strong impact. It is up to you to keep back up copies of data to  
protect against its loss.  
In no event shall CASIO Computer Co., Ltd. be liable to anyone for special, collateral, incidental,  
or consequential damages in connection with or arising out of the purchase or use of these  
materials. Moreover, CASIO Computer Co., Ltd. shall not be liable for any claim of any kind  
whatsoever against the use of these materials by any other party.  
• The contents of this user’s guide are subject to change without notice.  
• No part of this user’s guide may be reproduced in any form without the express written  
consent of the manufacturer.  
• The options described in Chapter 10 of this user’s guide may not be available in certain  
geographic areas. For full details on availability in your area, contact your nearest CASIO  
dealer or distributor.  
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ALGEBRA FX 2.0  
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1
Contents  
Contents  
Getting Acquainted — Read This First!  
Chapter 1 Basic Operation  
1-1 Keys.................................................................................................. 1-1-1  
1-2 Display.............................................................................................. 1-2-1  
1-3 Inputting and Editing Calculations .................................................... 1-3-1  
1-4 Option (OPTN) Menu ....................................................................... 1-4-1  
1-5 Variable Data (VARS) Menu ............................................................. 1-5-1  
1-6 Program (PRGM) Menu.................................................................... 1-6-1  
1-7 Using the Set Up Screen.................................................................. 1-7-1  
1-8 When you keep having problems… .................................................. 1-8-1  
Chapter 2 Manual Calculations  
2-1 Basic Calculations ............................................................................ 2-1-1  
2-2 Special Functions ............................................................................. 2-2-1  
2-3 Specifying the Angle Unit and Display Format ................................. 2-3-1  
2-4 Function Calculations ....................................................................... 2-4-1  
2-5 Numerical Calculations..................................................................... 2-5-1  
2-6 Complex Number Calculations ......................................................... 2-6-1  
2-7 Binary, Octal, Decimal, and Hexadecimal Calculations .................... 2-7-1  
2-8 Matrix Calculations ........................................................................... 2-8-1  
Chapter 3 List Function  
3-1 Inputting and Editing a List ............................................................... 3-1-1  
3-2 Manipulating List Data...................................................................... 3-2-1  
3-3 Arithmetic Calculations Using Lists .................................................. 3-3-1  
3-4 Switching Between List Files............................................................ 3-4-1  
Chapter 4 Equation Calculations  
4-1 Simultaneous Linear Equations........................................................ 4-1-1  
4-2 High Degree Equations .................................................................... 4-2-1  
4-3 Solve Calculations ............................................................................ 4-3-1  
4-4 What to Do When an Error Occurs ................................................... 4-4-1  
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Contents  
Chapter 5 Graphing  
5-1 Sample Graphs ................................................................................ 5-1-1  
5-2 Controlling What Appears on a Graph Screen ................................. 5-2-1  
5-3 Drawing a Graph .............................................................................. 5-3-1  
5-4 Storing a Graph in Picture Memory .................................................. 5-4-1  
5-5 Drawing Two Graphs on the Same Screen....................................... 5-5-1  
5-6 Manual Graphing .............................................................................. 5-6-1  
5-7 Using Tables ..................................................................................... 5-7-1  
5-8 Dynamic Graphing............................................................................ 5-8-1  
5-9 Graphing a Recursion Formula ........................................................ 5-9-1  
5-10 Changing the Appearance of a Graph............................................ 5-10-1  
5-11 Function Analysis ........................................................................... 5-11-1  
Chapter 6 Statistical Graphs and Calculations  
6-1 Before Performing Statistical Calculations........................................ 6-1-1  
6-2 Calculating and Graphing Single-Variable Statistical Data ............... 6-2-1  
6-3 Calculating and Graphing Paired-Variable Statistical Data .............. 6-3-1  
6-4 Performing Statistical Calculations ................................................... 6-4-1  
Chapter 7 Computer Algebra System and Tutorial Modes  
7-1 Using the CAS (Computer Algebra System) Mode .......................... 7-1-1  
7-2 Algebra Mode ................................................................................... 7-2-1  
7-3 Tutorial Mode.................................................................................... 7-3-1  
7-4 Algebra System Precautions ............................................................ 7-4-1  
Chapter 8 Programming  
8-1 Basic Programming Steps ................................................................ 8-1-1  
8-2 Program Mode Function Keys .......................................................... 8-2-1  
8-3 Editing Program Contents ................................................................ 8-3-1  
8-4 File Management.............................................................................. 8-4-1  
8-5 Command Reference ....................................................................... 8-5-1  
8-6 Using Calculator Functions in Programs .......................................... 8-6-1  
8-7 Program Mode Command List ......................................................... 8-7-1  
8-8 Program Library................................................................................ 8-8-1  
Chapter 9 System Settings Menu  
9-1 Using the System Settings Menu ..................................................... 9-1-1  
9-2 Memory Operations.......................................................................... 9-2-1  
9-3 System Settings ............................................................................... 9-3-1  
9-4 Reset ................................................................................................ 9-4-1  
9-5 Tutorial Lock ..................................................................................... 9-5-1  
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Contents  
Chapter 10 Data Communications  
10-1 Connecting Two Units................................................................... 10-1-1  
10-2 Connecting the Unit with a CASIO Label Printer.......................... 10-2-1  
10-3 Connecting the Unit to a Personal Computer ............................... 10-3-1  
10-4 Performing a Data Communication Operation ............................. 10-4-1  
10-5 Data Communications Precautions .............................................. 10-5-1  
10-6 Sending a Screen Shot ................................................................ 10-6-1  
10-7 Add-ins ......................................................................................... 10-7-1  
10-8 MEMORY Mode ........................................................................... 10-8-1  
Appendix  
1
Error Message Table ........................................................................... α-1-1  
Input Ranges .......................................................................................α-2-1  
Specifications.......................................................................................α-3-1  
Index ....................................................................................................α-4-1  
Key Index .............................................................................................α-5-1  
P Button (In case of hang up) ............................................................. α-6-1  
Power Supply .......................................................................................α-7-1  
2
3
4
5
6
7
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0
Getting Acquainted  
— Read This First!  
About this User’s Guide  
u! x(  
)
The above indicates you should press ! and then x, which will input a  
symbol. All  
multiple-key input operations are indicated like this. Key cap markings are shown, followed  
by the input character or command in parentheses.  
uFunction Keys and Menus  
• Many of the operations performed by this calculator can be executed by pressing function  
keys 1 through 6. The operation assigned to each function key changes according to  
the mode the calculator is in, and current operation assignments are indicated by function  
menus that appear at the bottom of the display.  
• This user’s guide shows the current operation assigned to a function key in parentheses  
following the key cap for that key. 1(Comp), for example, indicates that pressing 1  
selects {Comp}, which is also indicated in the function menu.  
• When (g) is indicated in the function menu for key 6, it means that pressing 6 displays  
the next page or previous page of menu options.  
uMenu Titles  
• Menu titles in this user’s guide include the key operation required to display the menu  
being explained. The key operation for a menu that is displayed by pressing K and then  
{MAT} would be shown as: [OPTN]-[MAT].  
6(g) key operations to change to another menu page are not shown in menu title key  
operations.  
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0-1-1  
Getting Acquainted  
uGraphs  
As a general rule, graph operations are shown on  
facing pages, with actual graph examples on the right  
hand page. You can produce the same graph on your  
calculator by performing the steps under the Procedure  
above the graph.  
5-1-1  
Sample Graphs  
5-1-2  
Sample Graphs  
5-1 Sample Graphs  
Example  
To graph  
y
=
3x2  
Procedure  
k
How to draw  
Description  
a
simple graph (1)  
1
2
3
m
GRPH-TBL  
dvxw  
To draw  
a
graph, simply input the applicable function.  
5(DRAW) (or w)  
Result Screen  
Set Up  
1. From the Main Menu, enter the GRPH  
Execution  
2. Input the function you want to graph.  
TBL Mode.  
Here you would use the V-Window to specify the range and other parameters of the  
graph. See 5-3-1.  
3. Draw the graph.  
Look for the type of graph you want on the right hand  
page, and then go to the page indicated for that graph.  
The steps under “Procedure” always use initial RESET  
settings.  
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The step numbers in the “SET UP” and “Execution” sections on the left hand page  
correspond to the “Procedure” step numbers on the right hand page.  
Example:  
Left hand page  
Right hand page  
3. Draw the graph.  
3 5(DRAW)(or w)  
uCommand List  
The Program Mode Command List (page 8-7) provides a graphic flowchart of the various  
function key menus and shows how to maneuver to the menu of commands you need.  
Example: The following operation displays Xfct: [VARS]-[FACT]-[Xfct]  
uPage Contents  
Three-part page numbers are centered at the top of  
each page. The page number “1-2-3”, for example,  
indicates Chapter 1, Section 2, page 3.  
1-2-2  
Display  
1-2-3  
Display  
The following explains the meaning of each icon.  
k
About the Function Menu  
Use the function keys (1 to 6) to access the menus and commands in the menu bar  
I
c
o
n
M
o
d
e
N
a
m
e
Description  
RUN  
Use this mode for arithmetic calculations and function  
calculations, and for calculations involving binary, octal,  
decimal, and hexadecimal values and matrices.  
along the bottom of the display screen. You can tell whether  
command by its appearance.  
a
menu bar item is  
a
menu or  
a
STATistics  
Use this mode to perform single-variable (standard  
deviation) and paired-variable (regression) statistical  
calculations, to perform tests, to analyze data and to draw  
statistical graphs.  
Command (Example:  
)
Pressing  
a
function key that corresponds to  
a
a
menu bar command executes the command.  
pull-up menu opens the menu.  
Pull-up Menu (Example:  
)
Pressing  
a
function key that corresponds to  
GRaPH-TaBLe  
DYNAmic graph  
Use this mode to store functions, to generate  
table of different solutions as the values assigned to  
variables in function change, and to draw graphs.  
Use this mode to store graph functions and to draw  
multiple versions of graph by changing the values  
assigned to the variables in function.  
a
numeric  
You can use either of the following two methods to select  
a
command from  
a
pull-up menu.  
a
a
a
RECURsion  
CONICS  
Use this mode to store recursion formulas, to generate  
numeric table of different solutions as the values assigned  
to variables in function change, and to draw graphs.  
a
Input the key to the left of the command on the pull-up menu.  
Use the and cursor keys to move the highlighting to the command you want, and then  
press w.  
a
f
c
Use this mode to draw graphs of implicit functions.  
The symbol  
submenu.  
'
to the right of  
a
command indicates that executing the command displays  
a
EQUAtion  
PRoGraM  
Use this mode to solve linear equations with two through  
six unknowns, quadratic equations, and cubic equations.  
To cancel the pull-up menu without inputting the command, press i.  
Use this mode to store programs in th program area and  
to run programs.  
k
About Display Screens  
This calculator uses two types of display screens:  
a
text screen and  
a
graphic screen. The  
Computer Algebra Use this mode to perform algebraic calculations.  
Syetem  
text screen can show 21 columns and  
function key menu. The graph screen uses an area that measures 127 (W)  
8
lines of characters, with the bottom line used for the  
63 (H) dots.  
×
ALGEBRA  
TUTORial  
LINK  
Use this mode for step-by-step solution of expressions.  
Text Screen  
Graph Screen  
Use this mode to determine the expression type and  
solve mode, and for interactive equation solutions.  
Use this mode for step-by-step solution of expressions.  
MEMORY  
SYSTEM  
Use this mode to manage data stored in memory.  
The contents of each type of screen are stored in independent memory areas.  
The contents of each type of screen are stored in independent memory areas.  
Use this mode to initialize memory, adjust contrast, and  
to make other system settings.  
#The contents of each type of screen  
are stored in independent memory  
areas.  
#The contents of each type of screen  
are stored in independent memory  
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19981001  
uSupplementary Information  
Supplementary information is shown at the bottom of each page in a “  
(Notes)” block.  
indicates a note about a term that appears in the same page as the note.  
*
# indicates a note that provides general information about topic covered in the same section  
as the note.  
19990401  

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