HP HP-10C User guide

HEWLETT-PACKARD
HP-10C
OWNERS HANDBOOK

Original scan copyright The Museum of HP Calculators
www.hpmuseum.org
Please support the HP Calculator Museum.
This version was translated to Microsoft Word and reformatted.
Version 1.
This document contains the following minor changes and corrections to the
original 1982 manual:
•The description of sine/cos/tangent in the function index uses correct key
symbols. Also added arcsine, arcos, arctan.
•Many index entries in the original manual appear to be incorrect. For
example, the entry for “Looping” that refers to page 81 in the original
manual. There is no mention of looping on page 81, but there is one at
the bottom of page 80. I corrected these as I found them.
•The “Adding Instructions Within a Program” heading in section 7 is black
instead of blue
•In the Table of Contents, section names are not followed by a colon.
•The index entries for keystrokes are slightly indented. This is because
they contain a hidden character that is the first letter of the keystroke’s
name. The hidden letter is necessary to get Word to put the index entries
in the right place.
•The Programming and Function Key Indexes do not have blue boxes
around the text.
•Incorrect keystroke images have been corrected (e.g., [LASTX] instead of
[LSTX] and [GRD] instead of [GRAD]).

HEWLETT PACKARD
HP-10C
Owner's Handbook
February 1982
00010-90025
Printed in U.S.A. Hewlett-Packard Company 1982

2
Introduction
Congratulations! Your selection of an HP-10C calculator with Continuous
Memory demonstrates your interest in quality, capability, and ease of use. You
may be an experienced HP calculator user or you may be using an HP calculator
for the first time. The primary goals of this handbook are to introduce you to all
of the HP-10C features and to help you learn as quickly as possible how to use
these features, regardless of your prior experience. Your anticipated use of the
HP-10C and your level of prior experience with HP programmable calculators
will determine how much time you need to devote to this handbook.
This handbook is divided into eight main sections. However, before reading
these sections, gain some experience using your HP-10C by working through
the introductory material entitled Your HP-10C: A Problem Solver, on page 7.
Section 1, Getting Started, covers the general operating information that both
new and experienced HP calculator users should know. Sections 2 through 4
cover information that is more important to new users.
Sections 5 through 8 describe how to use the programming capabilities of the
HP-10C.
The various appendices describe additional details of calculator operation, as
well as warranty and service information.
The Function Key Index and Program Key Index at the back of the handbook
can be used for quick reference to each function key and as a handy page
reference to the comprehensive information inside the manual.

3
Contents
Introduction.....................................................................................2
Contents...........................................................................................3
Your HP-10C: A Problem Solver....................................................7
Manual Solutions....................................................................................8
Programmed Solutions............................................................................ 9
Part I HP-10-C Basics ...................................................................11
Section 1 Getting Started ..............................................................12
Power On and Off ........................................................................... 12
Low-Power Indication........................................................................... 12
Keyboard Operation.............................................................................. 12
Primary and Alternate Functions........................................................ 12
Clearing Prefixes............................................................................... 13
Negative Numbers............................................................................. 13
Keying in Exponents ......................................................................... 13
Display Clearing ............................................................................... 14
One-Number Functions ..................................................................... 14
Two-Number Functions and the vKey.................................... 14
Special Displays ................................................................................... 17
Annunciators..................................................................................... 17
Radix Mark and Digit Separator ........................................................ 17
Error Messages.................................................................................. 17
Overflow and Underflow................................................................... 17
Memory................................................................................................18
Continuous Memory.......................................................................... 18
Resetting Memory............................................................................. 18
Section 2 The Automatic Memory Stack, LAST X, and Data Storage
........................................................................................................20
The Automatic Memory Stack and Stack Manipulation......................... 20
Stack Manipulation Functions ........................................................... 21
Calculator Functions and the Stack.................................................... 22
Two-Number Functions..................................................................... 23
Chain Calculations ............................................................................ 24
LAST X............................................................................................25
Constant Arithmetic .......................................................................... 26

4 Contents
Storage Register Operations ..................................................................28
Storing Numbers ...............................................................................29
Recalling Numbers............................................................................29
Clearing Data Storage Registers.........................................................30
Storage Register Arithmetic...............................................................30
Storage Register Arithmetic Exercises ...............................................31
Problems...........................................................................................31
Section 3 Numeric Functions ........................................................33
Pi..........................................................................................................33
Number Alteration Functions ................................................................33
One-Number Functions .........................................................................33
General Functions .............................................................................34
Trigonometric Operations..................................................................34
Trigonometric Functions....................................................................35
Time and Angle Conversions.............................................................35
Degrees/Radians Conversions............................................................36
Logarithmic Functions.......................................................................36
Two-Number Functions.........................................................................37
Percentages .......................................................................................37
The Power Function ..........................................................................38
Polar/Rectangular Coordinate Conversions ........................................38
Statistics Functions ...............................................................................39
Accumulating Statistics .....................................................................39
Correcting Accumulated Statistics .....................................................42
Mean.................................................................................................43
Standard Deviation............................................................................43
Linear Regression..............................................................................45
Linear Estimation and Correlation Coefficient ...................................46
Section 4 Display Control..............................................................49
Display Mode Control...........................................................................49
Fixed Decimal Display ......................................................................49
Scientific Notation Display................................................................50
Engineering Notation Display............................................................51
Mantissa Display...................................................................................52
Rounding at the Tenth Digit ..................................................................52
Part II Programming ....................................................................55
Section 5 Programming Basics......................................................56
Why Use Programs?..............................................................................56
Creating a Program ...............................................................................56
Running a Program ...............................................................................57
Program Memory ..................................................................................58
Identifying Instructions in Program Lines ..........................................59

Contents 5
Displaying Program Lines ................................................................. 60
The t00 instruction and Program line 00.................................... 61
Expanding Program Memory; the WKey.....................................62
Setting the Calculator to a Particular Program Line............................ 64
Executing a Program One Line at a Time .............................................. 65
Interrupting Program Execution ............................................................ 66
Pausing During Program Execution ................................................... 66
Stopping Program Execution Automatically....................................... 67
Stopping Program Execution Manually.............................................. 70
Nonprogrammable Functions ................................................................ 70
Section 6 Branching and Looping.................................................71
Simple Branching ................................................................................. 71
Looping ............................................................................................71
Conditional Branching .......................................................................... 74
Section 7 Program Editing ............................................................83
Changing an Instruction in a Program Line............................................ 83
Adding Instructions at the End of a Program ......................................... 83
Adding Instructions Within a Program .................................................. 84
Adding Instructions by Replacement ................................................. 84
Adding Instructions by Branching ..................................................... 85
Section 8 Multiple Programs.........................................................88
Storing Another Program ...................................................................... 88
Running Another Program..................................................................... 90
Appendix A Stack Lift and LAST X.............................................91
Digit Entry Termination........................................................................ 91
Stack Lift.............................................................................................. 91
Disabling Operations......................................................................... 91
Enabling Operations.......................................................................... 91
Neutral Operations ............................................................................ 92
LASTX.................................................................................................93
Appendix B Error Conditions.......................................................94
Error 0: Improper Mathematics Operation......................................... 94
Error 1: Storage Register Overflow.................................................... 94
Error 2: Improper Statistical Operation.............................................. 94
Error 3: Statistical Register(s) Unavailable ........................................ 95
Error 4: Improper Line Number......................................................... 95
Error 5: Improper Register Number ................................................... 95
Error 9: Service................................................................................. 95
Pr Error............................................................................................. 95
Appendix C Battery, Warranty, and Service Information...........96

6 Contents
Batteries................................................................................................96
Low-Power Indication .......................................................................97
Installing New Batteries ....................................................................98
Verifying Proper Operation (Self-Tests) .............................................. 100
Limited One-Year Warranty................................................................ 101
What We Will Do............................................................................101
What Is Not Covered ....................................................................... 101
Warranty for Consumer Transactions in the United Kingdom........... 102
Obligation to Make Changes............................................................102
Warranty Information......................................................................102
Service................................................................................................103
Obtaining Repair Service in the United States......................................103
Obtaining Repair Service in Europe.................................................103
International Service Information.....................................................105
Service Repair Charge..................................................................... 105
Service Warranty............................................................................. 105
Shipping Instructions.......................................................................105
Further Information ......................................................................... 106
Programming and Applications Assistance .......................................... 106
Dealer and Product Information...........................................................106
Temperature Specifications ................................................................. 107
Federal Communications Commission Radio Frequency Interference
Statement............................................................................................107
Function Key Index.....................................................................108
Conversions ....................................................................................108
Digit Entry......................................................................................108
Display Control...............................................................................108
Logarithmic and Exponential........................................................... 108
Mathematics....................................................................................109
Number Alteration........................................................................... 109
Prefix Keys .....................................................................................109
Stack Manipulation.......................................................................... 109
Statistics..........................................................................................109
Storage............................................................................................110
Trigonometry ..................................................................................110
Programming Key Index.............................................................111
Subject Index...............................................................................112
The HP-10C Keyboard and Continuous Memory......................118

7
Your HP-10C:
A Problem Solver
Your HP-10C Programmable Scientific Calculator is a powerful problem solver
that you can carry with you almost anywhere. It handles problems ranging from
the simple to the complex, and can remember data. The HP-10C is so easy to
program and use that it requires no prior programming experience or knowledge
of programming languages.
An important new feature of your HP-10C is its extremely low power
consumption. This efficiency is responsible for the lightweight, compact model
design, and eliminates the need for a cumbersome recharger. Power
consumption in the HP-10C is so low that the average battery life in normal use
is 6 to 12 months. In addition, the low-power indicator gives you plenty of
warning before the calculator stops functioning.
The HP-10C also helps you to conserve power by automatically shutting its
display off if it is left inactive for several minutes. But don't worry about losing
data—any information you have keyed into your HP-10C is saved by
Continuous Memory.
Your Hewlett-Packard calculator uses a unique operating logic, represented by
the vkey, that differs from the logic in most other calculators. The power
in HP calculator logic becomes obvious through use. Later we will cover the
details of this logic, but right now let's get acquainted with vin
performing calculations.
For example, let's look at the arithmetic functions. First we have to get the
numbers into the machine. To do this, key in the first number, press vto
separate the first number from the second, then key in the second number and
press +, -, *or ÷. Answers appear immediately after you press a
numerical function key.
To get the feel of your new calculator, turn on the
display by pressing the =key. If any nonzero
digits appear, you can press `to clear the
display to 0.0000. If four digits are not displayed
to the right of the decimal point, press ´•
4 now so your display will match those in the
following problems. (Displays illustrated in this
handbook are set to the • 4 display setting
unless otherwise specified.).
Note: An asterisk (*) flashing in the lower

8 Your HP-10C: A Problem Solver
left corner of the display when the calculator is turned on
signifies that the available battery power is running low. To install
new batteries, refer to appendix C.
Manual Solutions
It is not necessary to clear the calculator between problems. But if you make a
digit entry mistake, press `and key in the correct number.
*
To Solve: Keystrokes Display
9 + 6 = 15 9 v 6 + 15.0000
9 − 6 = 3 9 v 6 - 3.0000
9 × 6 = 54 9 v 6 * 54.0000
9 ÷ 6 = 1.5 9 v 6 ÷ 1.5000
Notice that in the four examples:
•Both numbers are in the calculator before you press +, -, *, or
÷.
•vis used only to separate two numbers that are keyed in one after
the other.
•Pressing a numerical function key, in this case +, -, *, or ÷
causes the function to execute immediately and the result to be displayed.
To see the close relationship between manual and programmed problem-
solving, let's first calculate the solution to a problem manually, that is, from the
keyboard. Then we'll use a program to calculate the solution to the same
problem and others like it.
Most conventional home water heaters are cylindrical in shape. You can easily
calculate the heat loss from such a tank using the formula q= h× A× T, where:
*If you are new to HP calculators, you will notice most keys have two labels. For the
main function—printed in white on top of the key—just press that key. For the function
printed in gold, press the ´ key first.

Your HP-10C: A Problem Solver 9
qis the heat loss from the water
heater (Btu per hour).
his the heat-transfer coefficient.
Ais the total surface area of the
cylinder.
Tis the temperature difference
between the cylinder and the
surrounding air.
Example: Assume you have a 52-gallon
cylindrical water heater and you wish to
determine how much energy is being lost because of poor insulation. In initial
measurements, you found an average temperature difference between the heater
surface and surrounding air of 15° F. The surface area of the tank is 30 square
feet and the heat transfer coefficient is approximately 0.47. To calculate the heat
loss of the water heater, simply press the following keys in order.
Keystrokes Display
15v
30
15.0000
30. Input temperature
difference (T) and area
of water heater {A).
*450.0000 Calculates A× T.
.47 0.47 Heat-transfer coefficient
(h).
*211.5000 Heat loss in Btu per hour
(h × AT).
Programmed Solutions
The heat loss for the water heater in the preceding example was calculated for a
15° temperature difference. But suppose you want to calculate the heat loss for
several temperature differences? You could perform each heat loss calculation
manually. However, an easier and faster method is to write a program that will
calculate the heat loss for any temperature difference.
Writing the Program. The program is the same series of keystrokes you
executed to solve the problem manually.
Loading the Program. To load the instructions of the program into the HP-10C
press the following keys in order. The calculator records (remembers) the
instructions as you key them in. (The display gives you information you will
find useful later, but which you can ignore for now.)

10 Your HP-10C: A Problem Solver
Keystrokes Display
¥00- Places the HP-10C in
Program mode. (Program
annunciator appears.)
´CLEARM 00- Clears program memory.
v 01- 36
3 02- 3
0 03- 0
* 04- 20
. 05- 48
4 06- 4
7 07- 7
*08- 20
The same keys you
pressed to solve the
problem manually.
¥ 211.5000 Places the HP-10C in
Run mode. (Program
annunciator cleared)
Running the Program. Press the following keys to run the program.
Keystrokes Display
15 15. The first temperature
difference.
¦211.5000 The Btu heat loss you
calculated earlier by
hand.
18¦ 253.8000 The Btu heat loss for a
new temperature
difference.
With the program you have loaded, you can now
quickly calculate the Btu heat loss for many
temperature differences. Simply key in the
desired difference and press ¦. For example,
complete the table at the right.
The answers you should see are 141.0000,
169.2000, 197.4000, 225.6000, 253.8000, and
282.0000.
Programming is that easy! The calculator remembers a series of keystrokes and
then executes them whenever you wish. Now that you have had some
experience in using your HP-10C, let's take a look at some of the calculator’s
important operating details.

Part I
HP-10C
Basics

12
Section 1
Getting Started
Power On and Off
The =key turns the HP-10C on and off.
*
To conserve power, the HP-10C
automatically turns itself off after several minutes of inactivity.
Low-Power Indication
When a flashing asterisk, which indicates low battery
power, appears in the lower left-hand side of the
display, there is no reason to panic. You still have
plenty of calculator time remaining: at least 15
minutes if you continuously run programs, and at least an hour if you manually
perform operations. Refer to appendix C (page 96) for information on replacing
the batteries.
Keyboard Operation
Primary and Alternate Functions
Most keys on your HP-10C perform one primary and one alternate function. The
primary function of any key is indicated by the character(s) on the upper face of
the key. The alternate function is indicated by the character(s) printed in gold
above the key.
•To select the alternate function printed in gold
above a key, first press the gold prefix key
´, then press the function key. For example:
´$.
•To select the primary function printed on the
face of a key, press only that key. For
example: ”.
*Note this key is shorter than the others to prevent its being inadvertently pressed.

Section 1: Getting Started 13
Notice that when you press the ´ prefix key, the fannunciator appears and
remains in the display until a function key is pressed
to complete the sequence.
Clearing Prefixes
Certain function commands require two parts: a prefix and a number or another
key. The prefixes are ´, O, l, and t; ´• ´i, and
´^. If you make a mistake while keying in a prefix for a function, press
´CLEARuto cancel the error. The ukey is also used to show
the mantissa of a displayed number, so all 10 digits of the number in the display
will appear for a moment after the ukey is pressed.
Negative Numbers
To make a displayed number negative—either one that has just been keyed in or
one that has resulted from a calculation—simply press ”(change sign).
When the display shows a negative number, pressing ”removes the minus
sign from the display, making the number positive.
Keying in Exponents
“(enter exponent) is used whenever an exponent is a part of a number you
are keying in. To use “, first key in the mantissa, then press “and key
in the exponent. For example, to key in Avogadro's number (6.0225×10
23
):
Keystrokes Display
6.0225 6.0225
“ 6.0225 00 The 00 prompts you to
key in the exponent.
2 6.0225 02
3 6.0225 23 (6.0225×10
23
)
v 6.0225 23 Enters number.
To key in a number having a negative exponent of 10, first key in the number,
press “, then key in the exponent, and then press ”(change sign) to
make the exponent negative.
*
For example, key in Planck's constant
(6.6262×10
−34
Joule-seconds) and multiply it by 50:
Keystrokes Display
6.6262“6.6262 00
34 6.6262 34
*”may also be pressed before the exponent, with the same result (unlike the
mantissa, whose number entry must precede ”).

14 Section 1: Getting Started
Keystrokes Display
”6.6262 -34
v 6.6262 -34
50* 3.3131 -32 Joule-seconds.
Note: Decimal digits from the mantissa which spill into the
exponent field will disappear from the display when you press
“, but will be retained internally.
“will not operate with a number having more than seven digits to the left
of the decimal point or radix, or with a mantissa whose absolute value is smaller
than 0.000001. To key in such a number, use a form having a higher or lower
exponent value, as appropriate. For example, 123456789.8×10
23
can be keyed in
as 1234567.898×10
25
; 0.00000025×10
−15
can be keyed in as 2.5 ×10
−22
.
Display Clearing
•In Run mode, pressing `(clear X) clears all digits in the display (X-
register) to zero.
•In Program mode, `is programmable; it does not delete the
currently displayed instruction. It is stored in the calculator as a
programmed instruction.
One-Number Functions
A one-number function is any numeric function that performs an operation
using only one number. To use any one-number function:
1. Key the number into the display (if it is not already there).
2. Press the function key(s).
Keystrokes Display
45 45.
´o 1.6532
Two-Number Functions and the v
vv
vKey
A two-number function must have two numbers present in the calculator before
executing the function. +, -, *and ÷are examples of two-number
functions.
As in basic arithmetic, the two numbers should be keyed into the calculator in
the order they would appear if the calculation were written down on paper from
left to right.

Section 1: Getting Started 15
The vKey. If one of the numbers you need for a two-number function is
already in the calculator as the result of a previous operation, you do not need to
use the vkey. However, when you must key in two numbers before
performing a function, use the vkey to separate the two numbers.
To place two numbers into the calculator and perform a two number function
such as 2 ÷ 3:
1. Key in the first number.
2. Press vto separate the first number from the second.
3. Key in the second number.
4. Press the function key(s).
Keystrokes Display
22.
v 2.0000
3 3.
÷0.6667
Now try this problem. Notice that you have to press vto separate
numbers only when they are being keyed in one immediately after the other. A
previously calculated result (intermediate result) will be automatically separated
from a new number you key in.
To solve (9 + 17 − 4 + 23) ÷ 4:
Keystrokes Display
9v 9.0000
17+ 26.0000 (9 + 17).
4-22.0000 (9 + 17 − 4).
23+45.0000 (9 + 17 − 4 + 23).
4÷11.2500 (9 + 17 − 4 + 23) ÷ 4.
Even more complicated problems are solved in the same simple manner—using
automatic storage of intermediate results. (For problems with nested
parentheses, refer to Chain Calculations, page 24.)
Example: Solve (6 + 7) × (9 − 3).
First solve for the intermediate result of (6 + 7):
Keystrokes Display
6 6.
v 6.0000
7 7.

16 Section 1: Getting Started
Keystrokes Display
+ 13.0000 (6 + 7).
Now perform (9 − 3). Since another pair of numbers must be keyed in, one
immediately after the other, use the vkey again to separate the first
number (9) from the second (3). (There is no need to press vto separate
the 9 from the previous intermediate result of 13 that is already in the
calculator—the results of previous calculations are stored automatically.) To
solve (9 − 3):
Keystrokes Display
9 9.
v 9.0000
3 3.
- 6.0000 (9 − 3).
Then multiply the intermediate results (13 and 6) together for the final answer.
Keystrokes Display
* 78.0000 (6 + 7) × (9 − 3) = 78.
Notice that the HP-10C automatically stored the intermediate results for you
and used them on a last-in, first-out basis when it was time to multiply. No
matter how complicated a problem may look, it can always be reduced to a
series of one- and two-number operations.
Remember:
•The vkey is used for separating the second number from the first
in any operation requiring the sequential entry of two numbers.
•Any new digits keyed in following a calculation are automatically treated
as a new number.
•Intermediate results are stored on a last-in, first-out basis.
Now try these problems. Work through them as you would with pencil and
paper. Don't be concerned about intermediate answers—they are handled
automatically by your HP-10C.
(16 × 38) − (13 × 11) = 465.0000
(27 + 63) ÷ (33 × 9) = 0.3030
0.55)(16.38× ÷ 0.05 = 60.0300
4 × (17 − 12) ÷ (10 − 5) = 4.0000

Section 1: Getting Started 17
Special Displays
Annunciators
Your HP-10C display contains five annunciators that tell you the status of the
calculator during certain operations. The annunciators are described, with the
operations they refer to, in the appropriate sections of this handbook.
Radix Mark and Digit Separator
A radix mark is the divider between the integer and fractional portions of a
number. A digit separator distinguishes the groups of digits in a large number.
In some countries the radix is a decimal point and the digit separator is a
comma, while in other countries the reverse is true. To interchange the radix
and digit separator conventions on your HP-10C, turn off the calculator, then
hold down the .key, turn the calculator back on, and release the .key
(./=).
Error Messages
If you attempt a calculation using an improper parameter, such as attempting to
find the square root of a negative number, an error message will appear in the
display. For a complete listing of error messages and their causes, refer to
appendix B.
Keystrokes Display
4” ¤ Error 0
` -4.0000
To clear any error message, press `(or any other key), then resume normal
calculator operation.
Overflow and Underflow
Overflow. When the result of a calculation in the
display (X-register) is a number with a
magnitude greater than 9.999999999 × 10
99
, all
9's are displayed with the appropriate sign. When

18 Section 1: Getting Started
overflow occurs in a running program, execution halts and the overflow display
appears.
Underflow. If the result of a calculation is a number with a magnitude less than
1.000000000 × 10
−99
, zero will be substituted for that number. Underflow will
not halt the execution of a calculation or a running program.
Memory
Continuous Memory
The Continuous Memory feature in your HP-10C retains the following in the
calculator, even when the display is turned off:
•All numeric data stored in the calculator.
•All programs stored in the calculator.
•Display mode and setting.
•Trigonometric mode (Degrees, Radians, or Grads).
When the HP-10C is turned on, it always “wakes up” in Run mode (PRGM
annunciator cleared), even if it was in Program mode (PRGM annunciator
displayed) when last turned off.
If the calculator is turned off, Continuous Memory is preserved for a few
minutes when the batteries are removed. Data and programs are preserved
longer than the calculator’s status is. Refer to appendix C for instructions on
changing batteries.
Resetting Memory
If at any time you want to reset (entirely clear) the HP-10C Continuous
Memory, do the following:
1. Turn the HP-10C off.
2. Hold down the -key, and press =.