Dec 252017
PC Emulated versions of the Hewlett-Packard 11C, 12C and 16C calculators. Mapping of the keyboards are given with each calculator display.
File XACT.ZIP from The Programmer’s Corner in
Category Science and Education
PC Emulated versions of the Hewlett-Packard 11C, 12C and 16C calculators. Mapping of the keyboards are given with each calculator display.
File Name File Size Zip Size Zip Type
X11SHARE.DOC 68949 18708 deflated
X11SHARE.EXE 59099 35301 deflated
X12SHARE.DOC 75923 19921 deflated
X12SHARE.EXE 61787 36490 deflated
X16SHARE.DOC 78363 20670 deflated
X16SHARE.EXE 63371 36766 deflated

Download File XACT.ZIP Here

Contents of the X11SHARE.DOC file

Shareware XACT-11C

The Hewlett-Packard Compatible

Scientific Calculator


CalcTech Incorporated

13629 Bellevue-Redmond Rd., Suite 202

Bellevue, WA. 98005

Sales, 9:00AM-5:00PM Pacific time

Tech Support,Info Line,24 Hour Voice Mail


This shareware version of XACT-11C is not a demo program! It is
a complete, full featured Scientific Calculator for MS-DOS
computers, equivalent to the Hewlett-Packard HP-11C handheld

Since it is a shareware program, you may make copies and
distribute them to your friends and co-workers, on bulletin board
systems, and so on. However, you may not modify this program or
documentation in any manner, nor may you distribute the program
or documentation for profit (handling fees are OK).

License Agreement






HP-11C, HP-12C, and HP-16C are trademarks of Hewlett-Packard
PC-DOS, IBM-PC, PC-XT, PC-AT and PS/2 are trademarks of IBM.
MS-DOS, Microsoft, and Word are trademarks of Microsoft Corp.
Tornado Notes is a trademark of Micro Logic Corp.
Hotline is a trademark of General Information, Inc.

(C)Copyright 1986-1989, 1990 by CalcTech Inc. Specifications
herein are subject to change without notice.

- 2 -

Registration & Commercial Version Upgrade

When you register XACT-11C for only $28.00 + $4.00 shipping,
we'll mail you the COMMERCIAL VERSION UPGRADE to the program. It
contains a number of features not available in this shareware
version including:

o TSR RAM-Resident (Pop-Up) capability
o Mouse Support
o Import/Export data from an application
o Full programming. Programs may be saved as disk files.
o Simulated tape which may be viewed, printed, stamped
with messages, and saved to disk.
o Typeset printed user's manual
o Discounts on future upgrades and notice of new products

Or, you may wish to register all three XACT calculators: the
for only $48.00 + $4.00 shipping, and receive COMMERCIAL VERSION
UPGRADES for all three calculators.

Why not register today?

- 3 -


| Quan | Description | Price | Total |
| | | | |
| | XACT-11C Scientific Calculator | $28.00 | |
| | | | |
| | XACT-12C Financial Calculator | $28.00 | |
| | | | |
| | XACT-16C Programmer's Calculator | $28.00 | |
| | SPECIAL OFFER! | | |
| | All 3 (XACT-11C, XACT-12C, XACT-16C) | $48.00 | |
| | |
| WA. state residents add 8.1% sales tax | |
| | |
Mail this form to: | Shipping/Handling | $4.00 |
CalcTech, Inc. Total | |
13629 Bellevue-Redmond Rd. Suite 202 Amount | |
Bellevue, WA. 98005 Enclosed +==========+
(206) 643-1682

Your Name: ______________________________ Phone: _____________________

Company (if applicable)________________________________________________

Address: ______________________________________________________________

City: ________________________________ State __________ Zip __________

[ ] Check Enclosed [ ] VISA [ ] Mastercard

Credit card #:____________________________________ Exp. Date: ____/____

Signature: ____________________________________________________________

Cardholder's name: ____________________________________________________

- 4 -

! ! ! ! P L E A S E R E A D T H I S ! ! ! !

This user's manual contains complete documentation for the
COMMERCIAL VERSION of XACT-11C. As such, several of the features
described within this manual will not be available with the
SHAREWARE VERSION of the program included on this disk.

We have included documentation for the COMMERCIAL VERSION UPGRADE
so that should you find benefit from the use of these programs
and decide to register (and we hope you will), you would have a
good idea of what to expect from the COMMERCIAL VERSION UPGRADE.
Please note that this is not the actual commercial version
documentation but rather a disk based "reprint". Should you
decide to register, you will receive a complete typeset printed
manual of the product(s).

XACT SERIES CALCULATORS are shareware, not freeware. Payment is
voluntary and on the "honor system". We ask that you register
the product(s) if after a short period of use, you find them
useful in your work. We hope that you appreciate the "try before
you buy" concept and that you will register.

Anyone who has ever purchased expensive (or even inexpensive)
software can attest to the frustration of being "burned" by a
lousy product. We think XACT SERIES CALCULATORS are excellent
products but we're giving you the opportunity to judge for
yourself. If you agree, please take a moment to register.

- 5 -


Section Title Page

1 Getting Started .......................................... 8

1.1 Introduction ......................................... 8
1.2 Other Guides ......................................... 8
1.3 System Requirements .................................. 9
1.4 Installing XACT-11C and Making Backups ............... 9
1.5 Command Line Options & Changing Hot Keys ............. 9

2 Loading XACT-11C .......................................... 10

2.1 XACT-11C Shareware Version ........................... 10
2.2 XACT-11C as a RAM Resident Program ................... 10
2.3 XACT-11C as a Removable RAM Resident Program ......... 10
2.4 XACT-11C as a Standalone DOS Program ................. 11
2.5 Keyboard Conventions ................................. 11
2.6 Function Keys ........................................ 11
2.7 Prefix Keys .......................................... 12
2.8 Entering Numbers ..................................... 12
2.9 Short Cut Keys ....................................... 12

3 Basic Operations .......................................... 13

3.1 Setting the Display Format ........................... 13
3.2 Arithmetic Calculations and RPN ...................... 13
3.3 Clearing Numbers ..................................... 14
3.4 Negative Numbers ..................................... 15
3.5 Mathematical Operations .............................. 15
3.6 Percentage Operations ................................ 15
3.7 Exponential Notation ................................. 16
3.8 Memory Storage Registers ............................. 17
3.9 Stack Operations ..................................... 17
3.10 The LastX Register ................................... 17
3.11 The Index Register and Using Memories Indirectly ..... 18

4 Scientific Functions ...................................... 19

4.1 Trigonometric Functions .............................. 19
4.2 Angle Conversions .................................... 19
4.3 Polar/Rectangular Conversions ........................ 20
4.4 Permutations and Combinations ........................ 20
4.5 Random Numbers ....................................... 20

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Section Title Page

5 Features (Commercial Version) ............................. 21

5.1 Getting Help ......................................... 21
5.2 Viewing the Tape ..................................... 21
5.3 Feeding a Result ..................................... 21
5.4 Stamping the Tape .................................... 21
5.5 Printing the Tape .................................... 22
5.6 Storing the Tape ..................................... 22
5.7 Loading a Program .................................... 22
5.8 Storing a Program .................................... 22
5.9 Importing Data from an Application ................... 23

6 Programming ............................................... 24

6.1 Entering a Program into XACT-11C ..................... 24
6.2 Labels in Programs ................................... 25
6.3 Using Subroutines .................................... 25
6.4 Returning from a Program or Subroutine ............... 26
6.5 Entering Data and the Run/Stop Key ................... 26
6.6 The [GoTo] Instruction ............................... 26
6.7 Branching Using the Index Register ................... 27
6.8 Program Loops Using the Index Register ............... 27
6.9 Program Loops and Branches Using the X and Y Registers 28
6.10 Branching on Flags Set/Clear ......................... 29
6.11 The Single Step Instruction .......................... 29
6.12 Moving to a Program Line Number ...................... 30
6.13 Inserting and Deleting Program Lines ................. 30

7 Statistical Calculations .................................. 31

7.1 Entering and Removing Numbers ........................ 31
7.2 Statistical Mean ..................................... 31
7.3 Standard Deviation ................................... 32
7.4 Linear Estimate ...................................... 32
7.5 Linear Regression .................................... 33

Appendix / Error Conditions ................................... 34

- 7 -

1 Getting Started

1.1 Introduction

XACT-11C is a software emulation of the famous Hewlett-Packard
HP-11C. If you are familiar with the HP-11C, you will find that
you already know how to use XACT-11C. If not, you'll find
XACT-11C easy to learn and use. It will become an invaluable
tool in your work.

XACT-11C is a RAM resident program (Commercial Version). It
remains loaded in your computer's memory ready to "pop-up" at the
activation of a "hot key", even if you're running another program
at the time. XACT-11C can also be run as a stand-alone DOS
program, if desired.

If you are already familiar with DOS and with the HP-11C, you may
only need to read Chapters 2 and 3. This will provide enough
information to get you started.

If you are new to DOS and/or the HP-11C, you may wish to read, or
at least skim, Chapters 1 through 6.


A number of the function keys on the XACT-11C use graphics
characters to represent them. Because this disk-based shareware
documentation is printed in ASCII text mode, some function keys
cannot be accurately shown in this file. We've tried our best to
emulate the look of the graphics symbols and to make it easy to
infer which functions are intended from the context of the

1.2 Other Guides

There are a number of guides and references available for the
HP-11C that can be used with XACT-11C as well. These are
generally available in bookstores and other places where Hewlett-
Packard calculators are sold. Some of these publications are
listed below.

"HP-11C Owner's Handbook and Problem Solving Guide" Covers
general operations, functions, applications, and programming of
the HP-11C. Published by the Hewlett-Packard Company.

Grapevine Publishing, Inc. P.O. Box 118, Corvallis, OR, 97339,
also has a number of publications about the HP-11C.

- 8 -

1.3 System Requirements

To operate the XACT-11C calculator, you will need an IBM PC, PC-
XT, PC-AT, PS/2, or close compatible equipped with at least the

256K RAM
One floppy disk drive
PC-DOS or MS-DOS version 2.00 or later

1.4 Installing XACT-11C and Making Backups

You should make a copy of the programs contained on the XACT-11C
diskette for backup purposes. Use the DOS "copy" command to copy
all the files to another diskette or to your hard disk. There may
be a file named README.DOC on your disk. If so, you should
examine it using your word processor or the DOS "type" command.

1.5 Command Line Options/Changing Hot-Keys (Commercial Version)

A command line option is an additional command typed when you
first load XACT-11C. There are several of these options
available. For example, if you wish to save memory space by
running XACT-11C in non RAM-Resident mode, you would use the
nopop command line option, i.e.:

x11 /nopop [ENTER]

([ENTER] means press the ENTER key). You can also change the
invocation "hot-key" using a command line option. Valid hot-key
definitions are Alt-Shift-S (default), Alt-S, and Alt-Ctrl-S.
For example, to change the invocation "hot-key" from it's default
setting of Alt-Shift-S to Alt-S, and also change the tapefile
name to test.txt in the \bin directory:

x11 /alt-s /tapefile=\bin\test.txt

The following is a list of available command line options:
(Commercial Version only)

/nopop Run XACT-11C in non RAM Resident mode.
/mono Force XACT-11C into monochrome mode.
/tapefile= Name of file used to save the tape.
/alt-s Change the invocation key to Alt-S.
/alt-ctrl-s Change the invocation key to Alt-Ctrl-S.
/sci Start up XACT-11C in scientific notation.
/nomouse Disable mouse operation.

- 9 -

2 Loading XACT-11C

2.1 XACT-11C shareware version

To load the Shareware XACT-11C, at the DOS prompt type:

x11share [ENTER]

2.2 XACT-11C as a RAM Resident program (Commercial Version)

To load XACT-11C, at the DOS prompt type:

x11 [ENTER]

You will see the copyright message appear on the screen. The
computer will then return to the DOS prompt and appear as if
nothing had happened. However, the XACT-11C calculator has now
been loaded into your computer's memory and is ready to pop-up at
the activation of the hot key. To activate XACT-11C, press:


XACT-11C will now appear on your screen, ready to perform
calculations. To exit from XACT-11C, press the Esc key.

2.3 XACT-11C as a Removable RAM-Resident Program (Commercial

When XACT-11C is loaded as a RAM Resident program as in section
2.1 above, it remains loaded in your computer's memory until your
computer is rebooted or powered off. There is another way to
install XACT-11C in such a way that it may be removed memory
without rebooting. To do so, you must use the TSRADD.COM and
TSRDROP.COM utilities provided. Using this method, to install
XACT-11C, you would type at the DOS prompt:

tsradd x11 [ENTER]
x11 [ENTER]

In fact, you may load RAM-Resident programs from other vendors as
well using the TSRADD.COM utility. For example, to load other
vendor's TSR's such as Tornado Notes and Hotline, you would type:

tsradd tn [ENTER]
tn [ENTER]
tsradd hotline [ENTER]
hotline [ENTER]

- 10 -

If you aren't running these programs from your current directory,
be sure to provide a complete pathname, or use the PATH command
provided with DOS.

To remove your memory resident programs, use the TSRDROP.COM
utility. It is necessary to drop your TSR's in the reverse order
that they were added. When you run TSRDROP.COM, the utility will
prompt you with the next TSR to be removed from memory. Press
ENTER to confirm the drop or Esc to exit the utility.

2.4 XACT-11C as a Stand Alone Program (Commercial Version)

XACT-11C defaults to being a RAM Resident program, but can also
be run as a stand-alone DOS program. To run XACT-11C as a stand-
alone program, type:

x11 /nopop

2.5 Keyboard Conventions

Throughout this manual, XACT-11C function keys are denoted within
a box. For example, the function key for the sine function is
shown as [SIN]. In the case of function keys which require a
prefix key (discussed in the next section), the prefix key is not
given in this manual since it can easily be determined.

Keys on the PC keyboard are listed in this manual using single
quotes such as 'a'. Numbers to be entered into XACT-11C are
shown in normal type.

2.6 Function Keys

XACT-11C has approximately 70 different function keys arranged in
the same ordering as on the HP-11C. Function keys are arranged
in groups of up to 3 functions per key; an upper, a lower and a
middle function all correspond to one function key. The upper
and lower functions are invoked by first pressing a prefix key
(discussed in the next section) and then the function key. The
middle function does not require the use of a prefix key. The PC
keystroke corresponding to function key is shown immediately to
the left of the function box.

The first row of function keys use the PC keys F1 through F10.
The second through fourth rows use the alphabetic characters as
arranged left to right on your PC keyboard.

For example, the [SIN] function on XACT-11C is invoked by
pressing the letter 'e' on the PC keyboard. Likewise, the [RCL]

- 11 -

function is invoked by pressing the letter 'b'. The [e^x]
function is invoke by pressing F2.

2.7 Prefix Keys

The left shift key and the right shift key on the PC keyboard
operate as prefix keys. They are equivalent to the gold [ f ]
key and the blue [ g ] key on the HP-11C. Prefix keys allow you
to activate the upper and lower functions assigned to a PC
function key. For example, to invoke the [HYP] function, you
would press and release the left shift key, and then press the
letter 'w'. Likewise, to invoke the [HYP-1] function, you would
press and release the right shift key and then press the letter
'w'. To invoke the [LOG] function, press and release the right
shift key, and then press F3.

2.8 Entering Numbers

To enter numbers into XACT-11C, use the numeric keypad on the
right side of your keyboard or the numbers on the typewriter
portion of the keyboard.

2.9 Short Cut Keys

You can use the Enter key on the PC, (also known as the Return
key) as the XACT-11C [ENTER] key as a short cut. Also, the '+',
'-', '*', and '/' keys adjacent to the numeric keypad function as
you would expect.

- 12 -


3.1 Setting the Display Format

When you first start it up, XACT-11C defaults to displaying 4
digits to the right of the decimal point. To change this
setting, you can use the [Fix], the [Sci] or the [Eng] function
keys followed by a number from 0 to 9 (enter numbers using the
numeric keypad). This number represents the number of digits
displayed to the right of the decimal point. The [Fix] function
is used to display numbers in fixed (non-exponential notation)
format. A number will not be displayed in exponential notation
unless it is too large to be displayed. The [Sci] function is
used to display numbers in scientific notation. The [Eng]
(Engineering) display function is much like the scientific
format except that the exponent displayed will always be a
multiple of 3 (kilo).

Note that the display format does not affect the number of
digits used to perform calculations, only the way in which they
are displayed. If you were using a 2 digit display format, the
number 12.006 would be shown on the display as 12.01. In this
example, the display has been rounded to 2 digits past the
decimal point. However, the internal representation of the
number is still kept as 12.006, and this value would be used in
subsequent calculations.

To round the number internally to match the number in the display
use the [Rnd] key. In the above example, if the [Rnd] key were
pressed, the internal value 12.006 would be converted to 12.01.
To set the display format for scientific notation, use the [Sci]
function key, again followed by a number between 0 and 9. For
engineering notation (the exponent is a multiple of 3), use the
[Eng] function key followed by a number between 0 and 9.

3.2 Arithmetic Calculations and RPN

You may already be familiar with Reverse Polish Notation (RPN).
RPN is a type of calculator logic that eliminates the need for
the equals key and the use of parenthesis in computations.
Instead, multiple operands are entered into the calculator
separated by the [ENTER] key. For example, to add the numbers 3
and 4:

Keystroke Display Comment
3 [ENTER] 3.00
4 [ + ] 7.00 Add 3 + 4

- 13 -

The result, 7.00 is now displayed. To multiply this result by 5:

Keystroke Display Comment
5 [ * ] 35.00 7.00*5.00

The way that XACT-11C performs these calculations with RPN is by
using a stack. The stack consists of 4 registers: X, Y, Z, and

Any number displayed is said to be in the X register. When the
[ENTER] key is pressed, a number in the X Register is pushed
into the Y Register and the previous number in the Y Register is
pushed into the Z Register. The previous number in the Z
register is pushed into the T Register. T stands for "Top" and
represents the top of the stack of numbers. The previous value
of the T register is lost. When a function key such as the [+]
key is pressed, the value held in the Y register is added to the
X register and this result is now stored in the X register.
Pressing [ENTER] does one other thing, it leaves the stack
disabled. This means that a number entered after the [ENTER] key
has been pressed is not pushed on the stack, it remains in the X
register. When a calculator function key is pressed, it utilizes
numbers on the stack to perform the function. Depending upon the
function, it may alter the X and/or Y registers, and also leave
the stack enabled or disabled.

Most operations leave the stack "enabled" so that the next number
entered will first push the stack. The [ENTER] and the [CLx]
functions are the most notable exceptions to this rule.

3.3 Clearing Numbers

You can clear a number in the display by pressing the [CLx]
function key. The calculator is now ready to accept another
entry. Unlike other calculators, XACT-11C does not require a key
for clearing a number and a different key for clearing the last
entry. Whether you have made a mistake in adding a series of
numbers, or simply wish to start a new calculation, use the [CLx]
function key. The [Bksp] key will clear a number in two
different manners. If you are in the process on entering a
number, but have not pressed a function key yet, the [Bksp] key
will clear the last numeric digit entered. On the other hand, if
the most recent key pressed was a function key (for example, the
[e^x] key), pressing [Bksp] works just like the [CLx] key, it
clears the number in the x register.

- 14 -

XACT-11C also contains other function keys to clear the

[S] Clear Sum. Used to clear the statistical registers
when perform statistics calculations.
[Prgm] Clear Program. Used to clear the program memory when
programming XACT-11C.
[Reg] Clear Registers. Used to clear all registers;
[Prfx] Clear the [ f ] or [ g ] prefix keys.

3.4 Negative Numbers

To change the sign of a number in the display, press the [ChS]
(Change Sign) function key. The [ChS] function will toggle the
sign of the value in the display. The [ChS] key is also used to
change the sign of an exponent if you are using exponential

3.5 Mathematical Operations

XACT-11C contains a large number of commonly used mathematical

[x^2] Square of a number.
[ x ] Square root of a number.
[Ln] Natural log of a number.
[Log] Base 10 log of a number.
[10^x] Raise 10 to the value in the x register
[e^x] Exponential of a number.
[1/X] Reciprocal of a number.
[Intg] Return the integer portion of a number.
[Frac] Return the fractional portion of a number.
[y^x] Raise a number to a power of another number.

3.6 Percentage Operations

Use the [ % ] key to calculate the percent amount of a number and
the [D%] to calculate the difference in percent one number is
from another.

Determine the total amount you would pay for a $39.95 radio if
the sales tax is 8.1%.

- 15 -

Keystroke Display Comment

39.95 [ENTER] 39.9500
8.1 [ % ] 3.2360 Sales tax
[ + ] 43.1860 Total paid.

You would pay $43.19 including sales tax.

What is 20% of $3500.00?

Keystroke Display Comment
3500 [ENTER] 3500.00
20 [ % ] 700.00

Example: Gasoline prices fell last month from an average of $1.09
to $.98. What percent difference does this represent?

Keystroke Display Comment
1.09 [ENTER] 1.0900
.98 [D%] -10.0917

Gasoline prices have fallen 10.09%.

3.7 Exponential Notation

Use exponential notation to enter very large or very small
numbers into XACT-11C. The [EEx] function key is used to enter
an exponent. For example, to enter the number 12 E09
(12,000,000,000) type:

Keystroke Display Comment
12 [EEx] 9 12.0000 +09

Likewise, to enter the number 12-09, type:

Keystroke Display Comment
[CLx] 0.0000
12 [EEx] 9 12.0000 +09
[ChS] 12.0000 -09

- 16 -

3.8 Memory Storage Registers

XACT-11C contains 20 different memory storage registers, used to
perform storage and memory arithmetic calculations. These
memories will retain their values until your computer is powered
off or re-booted. Memory registers in XACT-11C are referred to
as R0-R9 (for register 0 through 9), and R.0 through R.9. For
example, to store the value 20.3 in memory register 2, type:

Keystroke Display Comment
20.3 [Sto] 2 20.3000

To add the number 9.6 to the contents of register 2, type:

Keystroke Display Comment
9.6 [Sto] [ + ] 2 9.6000

Now, if you wish to view the contents of memory register 2, type:

Keystroke Display Comment
[Rcl] 2 29.9000

Memory register 2 contains the value 29.90.

3.9 Stack Operations

The [x<>y] function exchanges the contents of the X and Y
registers. The [R|] function rolls down the stack. The T
register is copied into the Z register. The Z register is copied
into the Y register, and the Y register is copied into the X
register. The X register is "rolled around" into the T register.

3.10 The LastX Register

The [LSTx] function key is not technically a part of the stack.
It is used to recover numbers entered just before a mathematical
operation was performed on the stack. The number recovered is
held in a register referred to as the LastX register. For
example, assume you meant to add the numbers 12 and 5 but
accidentally pressed 6 instead of 5.

Keystroke Display Comment
12 [ENTER] 12.00
6 [ + ] 18.00 Wrong value
[Lstx] 6.00
[ - ] 12.00 Subtract
5 [ + ] 17.00 Correct result

- 17 -

3.11 The Index Register and Using Memories Indirectly

Memories can also be accessed indirectly using the Index
register. The index register is accessed with the [I] function
key. A number may be stored in the index register using [Sto]
[I] and recalled from the index register using [Rcl] [I]. Also,
the [x<>I] function key is used to exchange the X register with
the Index register in the same fashion as the [x<>y] function key
is used to exchange the X and Y registers. For example:

Keystroke Display Comment
5 [Sto] [ I ] 5.0000 Register I= 5
20 [Sto] [(i)] 20.0000 Register 5 = 20
[CLx] 0.0000 Clear X reg
[Rcl] 5 20.0000 Reg 5 = 20

In the above example, the Indirect Index Register [(i)] was used
to store a number indirectly. The memory register accessed was
determined by the contents of the [I] register. Memories can
also be recalled indirectly using the operation [Rcl] [(i)], and
exchanged with the X register indirectly using the [x(i)]

- 18 -


XACT-11C provides a rich set of scientific and trigonometric
functions to choose from. Each of these will be described below.

4.1 Trigonometric Functions

XACT-11C contains a complete set of trigonometric functions,
including hyperbolics. Trig functions can be displayed in either
Degrees by pressing the [Deg] function key; Radians by pressing
the [Rad] function key, or Grads by pressing the [Grd] function
key. The available trig functions are as follows:

[Sin] Sine function
[Cos] Cosine function
[Tan] Tangent function
[Sin-1] Arc Sine function
[Cos-1] Arc Cosine function
[Tan-1] Arc Tangent function

In addition, the [Hyp] or the [Hyp-1] functions can be pressed
prior to pressing [Sin], [Cos], or [Tan] functions to compute the
hyperbolic or inverse hyperbolics of these functions.

Keystroke Display Comment
[Deg] Degree mode
30 [Sin] 0.5000 Sine of 30 degrees
[Rad] 0.5000 Use radian mode.
[Pi] 3.1416
[Cos] -1.0000 Cosine of Pi radians
[Deg] -1.0000 Use degree mode.
1 [Tan-1] 45.0000 Arc Tangent of 1

4.2 Angle Conversions

Use XACT-11C to convert from Degrees to Radians and from Radians
to Degrees with the [->Rad] and [->Deg] functions respectively.

You can also convert from fractional degrees (or fractional
hours) to minutes and seconds with the [->] key and from
minutes and seconds to fractional degrees with the [->H]
function key

Keystroke Display Comment
60 [Rad] 1.0472 Convert to radians
1.333 [] 1.1959 1 hr 19 min 59 sec

- 19 -

4.3 Polar/Rectangular Conversions

XACT-11C can convert between polar and rectangular coordinates
with the [->P] and [->R] functions respectively. For polar
coordinates, the magnitude "r" is placed/returned in the y
register, and the angle theta is placed in the x register. Theta
may be in degrees, radians, or grads depending upon the trig mode
set. For rectangular coordinates, the y coordinate is placed in
the y register and the x coordinate in the x register.

Keystroke Display Comment
1.3 1.3000 x = 1.3, y = 1.0
[->P] 1.6401 magnitude "r" = 1.6401
[x<>y] 37.5686 theta = 37.5686 degrees

4.4 Permutations and Combinations

XACT-11C can calculate the two most common probability functions.
Combinations are the number groups of y items, taken in groups of
x, without regard to their order. Permutations are the number of
different changes in position possible within a group of y where
the group size is x.

For example, the number of different permutations and
combinations of the group 1 through 7 inclusive, taken 3 at a
time are:

Keystroke Display Comment
7 [ENTER] 7.0000
3 [Cy,x] 35.0000 combinations
7 [ENTER] 7.0000
3 [Py,x] 210.0000 permutations

4.5 Random Numbers

XACT-11C will generate a different random number each time the
[Ran#] function key is pressed. The generated number will be in
the range 0 < n < 1. In addition, a random number "seed" may be
planted by storing an arbitrary number between 0 and 1 in the
Random number generator register.

Keystroke Display Comment
[Ran#] 0.4100 Random number
[Ran#] 0.1847 Random number
.123 [Sto] [Ran#] 0.1230 An arbitrary seed.
[Ran#] 0.6334 Random number with seed

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5. Features (Commercial Version only)

5.1 Getting Help

A Help menu is available when you are working with XACT-11C. To
obtain help press:


An information screen will appear in a window. The help menu can
be removed by pressing F1 again.

5.2 Viewing the Tape

XACT-11C provides a simulated tape display which keeps a record
of your calculations as you perform them. To view the tape


The tape will appear in a window. To remove the tape, press F2

5.3 Feeding a Result

To feed the result of a calculation into the program you're
running press:


The calculator will disappear and the number in the display will
be fed to your application.

5.4 Stamping the Tape

To stamp a message on the simulated tape press:


The message will appear on the tape as well as the printer or
tape disk file if either of these options are being used.

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5.5 Printing the Tape

To print the tape as you make calculations press:


To turn off printing, press F5 again.

5.6 Storing the Tape

The simulated tape may be saved to a disk file as you make
calculations. Each time you use XACT-11C, calculations are
appended to the tape file. To store the tape, press


The tape will be saved under the name X11.TAP in the current
directory. If you change directories, a different tape file
with the same name will be used. If you wish to use a
different name for your tape file, use the command line option
/tapefile=filename where filename is any valid DOS filename
which can include a path. (see section 1.6).

5.7 Loading a Program

To load a program previously saved press:


A window will appear requesting a file name. Enter the DOS
filename of the program you wish to retrieve.

5.8 Storing a Program

XACT-11C allows you to save programs as disk files. To save a
program on disk, press:


A window will appear prompting you for comments. You can enter
up to 3 lines of comments, associated with the program you are
saving. Press the Esc key after you have entered any comments.
Another window will appear prompting you for a filename. Enter
any valid DOS filename.

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5.9 Importing Data from an Application

You can "import" data from the screen of the previous program you
were running before popping-up XACT-11C. For instance, you may
be working with a spreadsheet or word-processing program and wish
to add a series of numbers from the display screen. To import
data, press:


You will see the screen you were working with before popping-up
XACT-11C. However, you have not returned to your previous
program. Use the up, down, left, or right arrow keys to move the
cursor to a number on the screen you wish to import. Then, press
F9 again to import the number into XACT-11C. It will appear
just as if you had typed it in by hand. If you now press F9
again, you'll see the cursor will have moved down a row. This is
to help facilitate the importing of a "column" of numbers. If
you wish to accept the data where the cursor rests, again press
F9. If not, use the arrow keys to move to the desired location.

It isn't possible to import data from a screen if the screen is
in graphics mode. In this case, XACT-11C will sound a beep
indicating that it can't import a number. One commonly used
program which utilizes graphics mode is Microsoft Word. If you
use Word, you should use text mode. Pressing Alt-F9 in Word
allows you to switch between graphics and text modes.

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Programming XACT-11C is a process whereby you "teach" the
calculator a series of keystrokes, similar to the way you would
normally enter the keystrokes if you were computing a problem
manually. In addition, you can have a program take different
actions in a program based upon values contained in registers.
For example, the program could take a different course of action
if the value contained in the X register is less-than-or-equal-to
the value in the Y register. This is known as "conditional
branching". Programming also allows you to repeat given
keystroke sequences a certain number of times. This is known as

If you are interested in advanced programming features of
XACT-11C, we suggest you obtain a copy of the "HP-11C Owner's
Handbook and Problem Solving Guide"

6.1 Entering a Program into XACT-11C

To begin entering a new program into XACT-11C, the calculator
must be placed in Program mode by pressing the [P/R] function
key. When in program mode, subsequent keystrokes are simply
stored in the calculator's internal memory. The [P/R] key
toggles between program and run modes.

Keystroke Display Comment
[P/R] 000- Program mode
[P/R] (as before) Run mode.

When first entering program mode, the display shows the value
000. This represents the current program line number of the
program you are entering. Line 000- is special in that it
always represents the beginning of program memory. Let's enter
a very simple program:

Keystroke Display Comment
[P/R] 000- Program mode
[Prgm] 000- Clear program memory
[Lbl] [ A ] 001- 42 21 11 Label begins program
1 002- 1
0 003- 0
[ENTER] 004- 36
4 005- 4
[ + ] 006- 10
[Rtn] 007- 43 32 Return from program
[P/R] Run mode

The program simply adds the numbers 10+4 and finishes. When
XACT-11C is in program mode, the numbers to the right of the

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program line are a code which represents which key was pressed.
The first digit of the number indicates the row and the second
indicates the column of where the key is positioned on the
XACT-11C screen. If you think of all the keystrokes on the
calculator face as being in a table with 4 rows and 10 columns,
each key can be identified as being in a certain row and column.
For example the [ENTER] key is located in Row 3, Column 6. Thus
in instruction line 03- the display contains the value 36.
Likewise the [ + ] key is in row 1, column 10, so the display
shows 10.]

To run the program:

Keystroke Display Comment
[ A ] 14.0000 Program result.

Be sure to use the [ A ] function key mapped to the number '1' on
the PC keyboard, not the letter 'A' on the PC keyboard.

6.2 Labels In Programs

There are 15 labels available in programming, 0-9 and A-E. The
previous example used the label [ A ] to identify the beginning
of the program. An alphabetic label is always used to begin a
program. Both alphabetic and numeric labels can be used as
labels within a program. Labels are also used as targets of
[Gto] (go to) and [Gsb] (go to subroutine) instructions. Labels
can also be used to separate programs in XACT-11C's memory; as a
way of keeping multiple programs in memory at the same time,
although this is generally not necessary since programs may be
saved as disk files.

6.3 Using Subroutines

A program can call a subroutine from within the program when the
[Gsb] instruction is used within the program. For instance, the
instruction [Gsb] 5 will transfer control to the program
instruction immediately following the instruction [Lbl] 5
contained elsewhere within the program. Control will transfer to
the label that identifies the subroutine. Subroutines can
"nest", that is one subroutine may call another which may call
another, and so on. The maximum level of subroutine nesting is

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6.4 Returning from a Program or Subroutine

The last instruction in a program must always be a [Rtn]. This
tells the program to reset it's program line number to 000 (go
back to the beginning) and stop executing. The [Rtn] instruction
is also the last instruction in a subroutine. In this case,
after the execution of the [Rtn] instruction, control is
transferred back to the instruction following the subroutine

6.5 Entering Data and the Run/Stop Key

There are generally 2 ways to get data into a program. The
easiest is to use the [Sto] instruction to store data in
registers prior to running the program. Then the program can
contain [Rcl] instructions to fetch the data from the register.
The second method is required when there is more data to be input
than available storage registers. It involves using the [R/S]
(run/stop) function key. When this key is encountered during
program execution, the program stops. At this point, you can
enter new data and then press the [R/S] key. The program will
begin running again.

Let's write a program to solve the equation z= 1/(x+y) using the
[R/S] key to allow us to enter both the x and y variables.

Keystroke Display Comment
[Prgm] Clear program memory
[Lbl] [ A ] 001- 42 21 11 Beginning of program
[ENTER] 002- 36 x value
[R/S] 003- 31 Stop to accept y value
[ + ] 004- 10 Add x + y
[1/x] 005- 15 Invert
[Rtn] 006- 43 32 End of program
[P/R] Return to run mode.

Now, to execute the program where x= 3 and y= 4:

Keystroke Display Comment
3 [ A ] 3.0000 Waiting for y input.
4 [R/S] 0.1429 Result

6.6 The [Goto] Instruction

The [Gto] instruction can be used to unconditionally jump to a
location in the program identified with a [Lbl] instruction.

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For example, let's write a program that will keep track of the
sum of the squares of a group of numbers we wish to enter.

Keystroke Display Comment
[Prgm] Clear program memory
[Lbl] [ A ] 001- 42 21 11 Beginning of program
0 002- 0
[ENTER] 003- 36 Clear x register
[Lbl] 2 004- 42 21 2 Label used for looping
[R/S] 005- 31 Stop to accept input
[x^2] 006- 43 11 Square the input value
[ + ] 007- 10 Add to sum of squares
[Gto] 2 008- 22 2 Branch to label

To calculate the sum of the squares of 3, 7, 11, and 15:

Keystroke Display Comment
[ A ] 0.0000 Waiting for 1st value
3 [R/S] 9.0000
7 [R/S] 58.0000
11 [R/S] 179.0000
15 [R/S] 404.0000

6.7 Branching Using the Index Register

In the previous example, we used a [Gto] instruction to branch to
a label, in this case, label 2. As previously mentioned, there
are 15 available labels, 0-9 and A-E. You can also use the
index register [I] to indirectly branch to a label, or indirectly
call a subroutine. If the [I] register contains a number
representing a label, the instructions [Gto] [I] and [Gsb] [I]
will indirectly branch to a label or indirectly call a

6.8 Program Loops Using the Index Register

XACT-11C contains 2 instructions that first increment or
decrement a special value contained in the index register and
either execute or skip the next program line depending upon the
condition met. These instructions are [Isg] (increment and skip
if greater), and [Dse] (decrement and skip less than or equal).
They can be used to control loops where the number of times to
execute the loop is contained in the index register.

Looping with the index register requires placing a special "coded
value" in the index register. This value is of the form:

- 27 -


In the encoding, aaaaa represents a starting value of a loop
counter and will default to 0 if it is not included. This
value is incremented or decremented each time the flow of
execution of the program encounters an [Isg] or [Dse] instruction
respectively. The value contained in aaaaa is then compared
against the value in bbb. In the case of the [Isg] instruction,
if the value aaaaa is greater than bbb, the instruction in the
program code which follows the [Isg] instruction will be skipped,
and program execution will begin immediately following the
skipped instruction. Likewise in the case of the [Dse]
instruction, if the value aaaa is less than or equal to the value
bbb, the same skipping over event will occur.

In the encoding, the value cc represents the count to increment
or decrement by each time the loop is executed.

For example, if we wanted to execute a group of instructions
within a loop 10 times where the loop counter begins at 10, and
decrements by steps of 1 until it reaches 0, we would place the
value 10.00001 in the index register. Notice that in the
encoding, aaaaa= 10, bbb= 000, and cc= 01. A program fragment
using this loop is shown below:

[Sto] [ I ]

[Lbl] [ A ]

(Instructions within loop)
[Gto] [ A ]

(Instructions after loop)

6.9 Program Loops and Branches Using the X and Y Registers

XACT-11C can also make "conditional tests" based upon values
contained in the X and Y registers. There are 8 different
possible conditions in all. These functions each execute the
next instruction in the program if the condition is true, and
skip over it if the condition is false. The instructions are
defined as:

[x<=y] true if x less than or equal to y
[x<0] true if x less than 0
[x>y] true if x greater than y
[x>0] true if x greater than 0
[x<>y] true if x not equal to y
[x<>0] true if x not equal to 0
[x=y] true if x equal to y
[x=0] true if x equal to 0

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6.10 Branching On Flags Set/Clear

XACT-11C contains two flags which can be set (1) or cleared (0)
and then may be later tested and a conditional jump may occur
depending on the state of the flags. The flags are Flag 0 and
Flag 1. The flags are set or cleared with the [SF] or the [CF]
function keys respectively. To set flag 1, for example, you
would press [SF] 1. You may test the status of a flag with the
[F?] function key within a program. Again, follow this key with
either 0 or 1 depending on which flag you wish to test. If the
flag was set, the instruction in memory immediately following the
[F?] will be executed. If not, the program will skip over this
instruction line number and proceed with execution at the next
line number.

The example below illustrates a program fragment utilizing flags

(Program instructions)
[Lbl] 3
[SF] 0
[Gto] B

(Program instructions)

[Lbl] 4
[CF] 0
[Gto] B

(Program instructions)

[Lbl] B
[F?] 0 (test to see if flag 0 is set)
[Gto] C (transfer control to label C if flag 0 set)
[Gto] D (transfer control to label D if flag 0 clear)

If the program executes at label 3, flag 0 is set and control is
transferred to label B. At this point, since flag 0 was set,
control will transfer to label C. Similarly, if the program
executes at label 4, flag 0 is cleared, and thus, when control is
transferred to label B, the flag test will fail. This will cause
the [Gto] D instruction to be executed.

6.11 The Single-Step Instruction

The [SST] (single-step) instruction can be used in either program
mode or run mode. In program mode, pressing [SST] will display
the next program line number in a program. In run mode, the
[SST] function can be used to execute a program one step at a
time. This is useful for program debugging. The [BST] (back-
step) instruction works like the [SST] instruction in program

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mode except that it displays the previous program line number in
a program. The [BST] instruction does not operate in run mode,
that is, it won't back-step execution of a program, only display
the previous program line number.

6.12 Moving to a Program Line Number

You can move to a specific line number in either program mode or
run mode. Press [Gto] [.] nnn where nnn is a 3 digit number
between 0 and 203. In run mode, pressing [R/S] will begin
execution at that line number.

6.13 Inserting and Deleting Program Lines

XACT-11C can edit an existing program by inserting or deleting
lines within the program. To do this, you must be in program
mode and move to the line number where you wish to make the
insertion/deletion using the [Gto] [.] nnn instruction where nnn
is the line number (described ] in section 6.12 above). To
insert a line, simply enter the instruction for the line you wish
to insert. The insertion will happen immediately following the
line and all other line numbers will be pushed ahead in memory.

To delete a line, move to the line you wish to delete and press
the [<-] function key.

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XACT-11C can perform common statistical calculations including
mean and standard deviation using it's built-in capabilities. In
addition, programs can be written to perform complex statistical

7.1 Entering and Removing Numbers.

The [S+] function key is used to enter a new number into the
statistical registers. XACT-11C can be used to perform
statistical operations using both one and two variables. When
using one variable, that variable is referred to as the X
variable. With two variable analysis, the second variable is
referred to as the Y variable.

When entering single variable numbers, enter the number and then
press the [S+] function key. Continue this process until all
numbers have been entered.

With two variables, first key in the Y variable and press the
[ENTER] key, then enter the X variable and press the [S+] key.

When the [S+] function key is used, memory registers 1 through 6
will hold intermediate values. You can use the [Rcl] function
key to view these values, or to use them within a program. The
values contained in registers 1 through 6 are summarized below:

R0 contains the value N, the number of data values
(or data pairs) entered thus far.
R1 contains the sum of all the X variable values.
R2 contains the sum of the squares of all the X variable values.
R3 contains the sum of all the Y variable values.
R4 contains the sum of the squares of all the Y variable values.
R5 contains the sum of the products of the X variable values
and the Y variable values.

To remove an incorrectly entered value, you can use the [S-]
function key. Simply re-enter the incorrect value and then press
the [S-] function key.

7.2 Statistical Mean

Example: Suppose you are a teacher with 5 students. Student's
scores on their last test were 80, 63, 77, 94, and 79. Find the
mean of the test results.

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Keystroke Display Comment
[S] Clear statistics
80 [S+] 1.0000 1st score
63 [S+] 2.0000 2nd score
77 [S+] 3.0000 3rd score
94 [S+] 4.0000 4th score
79 [S+] 5.0000 5th score
[xbar] 78.6000 Mean

The mean of the test scores is 78.6.

7.3 Standard Deviation

XACT-11C can be used to calculate the standard deviation of both
x and y variables using the [S] function key.

Example: Assume a set of students test scores for math and
English tests are as follows:

Student Math English
1 59 64
2 66 69
3 88 82
4 70 51

Calculate the standard deviation for the students results.

Keystroke Display Comment
[S] Clear registers
59 [ENTER] 64 [S+] 1.0000 1st student
66 [ENTER] 69 [S+] 2.0000 2nd student
88 [ENTER] 82 [S+] 3.0000 3rd student
70 [ENTER] 51 [S+] 4.0000 4th student
[S] 12.8193 Math standard deviation
[x<>y] 12.3659 English std. deviation

The standard deviation for the student's math scores was 12.82
and for the English scores was 12.37.

7.4 Linear Estimate

Using values entered for x and y variables, you can compute a
"best guess" for either variable, given a sample value for the
other one.

Example: Using the above data for student test scores, compute
an estimate for a student's English score given that the student

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has a math score of 80. Compute the correlation coefficient for
this value.

Keystroke Display Comment
80 [y,r] 78.8692 Math score estimate
[x<>y] 0.6235 correlation coefficient

7.5 Linear Regression

Linear regression is a method used for determining the "best fit"
straight line equation for a set of paired statistical data.
XACT-11C can determine the factors for the equation Y= MX + B
where M is the slope of the line and B is the Y intercept. The
[L.R.] function key returns the slope M in the Y register and
the intercept B in the X register.

Keystroke Display Comment
[L.R.] 30.7556 Y intercept
[R|] 0.6014 Slope

- 33 -


Error Conditions

When an error is encountered during operation, XACT-11C will
display the word "Error" in the calculator's display, followed by
a 1 digit error code. These error codes are defined below:

Error 0 - Invalid math operation. This error is encountered
when an operation attempted division by 0, the square root of a
negative number, or other invalid operation.

Error 1 - Out-of-Bounds Storage register operation. This
happens if a storage register operation overflows the range of
the calculator.

Error 2 - Invalid Statistical operation. This happens if a
statistical operation cannot be performed or is out of range, for
instance taking the mean of 0 numbers.

Error 3 - Invalid Register. An attempt was made to access a
label or line number that is out of range.

Error 4 - Invalid label or line number. An attempt was made to
access a label or line number that is out of range.

Error 5 - Invalid subroutine nesting. A subroutine was nested
more than 4 levels deep.

Error 6 - Invalid flag accessed. An invalid flag was accessed,
valid flags are 0 and 1.

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