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POCKET 

49504-6 

$3.95 



BY THE EDITORS OF 
CONSUMER GUIDE' 



THE USER'S GUIDE TO 

TEXAS 
INSTRUMENTS 

TI-99/4A COMPUTER, 
SOFTWARE, & PERIPHERALS 



BY THE EDITORS OF 
CONSUMER GUIDE* 

THE USER'S GUIDE TO 

TEXAS 
INSTRUMENTS 

TI-99/4A COMPUTER, 
SOFTWARE, & PERIPHERALS 



Another Original publication of POCKET BOOKS 




POCKET BOOKS, a division of Simon & Schuster, Inc. 
1230 Avenue of the Americas 
New York, N.Y. 10020 



Copyright © 1933 by Publications International, Ltd. 

All rights reserved, including the right to reproduce 
this book or portions thereof in any form whatsoever. 
For information address Pocket Books, 1230 Avenue 
of the Americas, New York, N.Y. 10020 

ISBN: 0-671-49504-6 

First Pocket Books printing December, 1983 
10 987654 3 21 

POCKET and colophon are registered trademarks 
of Simon & Schuster, Inc. 



Printed in the U.S.A. 



CONTENTS 



CHAPTER 1 

WELCOME TO HOME 

COMPUTING 4 

By using this book to learn about your 
system, you will be well on the way to 
many happy hours of home computing. 

CHAPTER 2 

GETTING STARTED 9 

You'll learn about what you need to 
assemble your basic computer system. 
Then you'll go step-by-step through the 
details of setting it up. 
• Troubleshooting Guide 

CHAPTER 3 

MEET THE KEYS 42 

Each and every key on your keyboard 
is presented here, complete with 
exercises to teach you how the keys 
work. Detailed photographs show you 
how your screen will look as you work 
through the exercises. 

CHAPTER 4 

PERIPHERALS — 
EXPANDING YOUR 

SYSTEM is? 

So you want your new system to do 
even more for you? Here's the 
background information you need to 
decide what additional equipment you 
might want to buy. 



CHAPTER 5 

SOFTWARE 

Software programs also expand your 
system's capabilities. Here are some 
software packages you might use for 
various kinds of purposes. 

CHAPTER 6 

YOUR COMPUTER S 
NETWORK 

Many resources are available to help 
you get the most from your computer 
system. You can share all sorts of 
information with other computer users 
and with national information banks 
as well 



CHAPTER 1 

WELCOME TO 
HOME COMPUTING 

Congratulations on owning your new Texas In- 
struments TI-99/4A Home Computerl If this is 
your.first experience in the world of home com- 
puters, you will discover that your computer 
opens a new world of entertainment and educa- 
tion to you. If you are upgrading from a less ex- 
pensive computer, you'll find that the TI-99/4A 
offers expansion capabilities that will serve the 
needs of many home computer enthusiasts, from 
the novice to the advanced programmer. 

You will quickly notice that the TI-99/4A is de- 
signed to be easy to use. And you'll undoubted- 
ly find many uses for your computer; precisely 
what those uses are will depend on your inter- 
ests. In learning to use your TI-99/4A, you'll be- 
come familiar with the use of your computer in 
particular, and computers in general. Becoming 
familiar with computers (i.e., becoming comput- 
er literate) is one of the primary benefits of 
owning a home computer. 



4 



A little of the basics helps us begin to realize just 
how useful computers can be. A computer, after 
all, is an electronic device that has the ability to 
process data. If "process data" sounds too tech- 
nical think of it this way: each time you look up 
an address and phone number or add all of the 
month's bills together, you are processing data. 
When you worry over your tax form each year, 
you are processing data. When you type a term 
paper or a letter and retype it to correct mis- 
takes, you are processing data (processing 
words, specifically). A computer can help you 
perform all of these tasks — and more. 

With the ability to store and recall electronic 
files, you can use your computer for countless 
household chores. Keeping close track of med- 
ical, dental, insurance, and automobile mainte- 
nance records are just some of the possibilities 
that come to mind. 

Tracking home finances is one of the most pop- 
ular applications for home computers. You can 
examine your budget plan expenses, and pro- 
ject your financial future based on expected 
salary adjustments and inflation. If you are con- 
sidering the costs of a new home, you can use 
the computer to calculate real estate financial 
values and provide comparisons between hous- 
ing choices. You can also calculate exact pay- 
ments on loans, adjusting for different interest 
rates. And at the end of the year, during your 
annual income tax planning ritual, you can use 
your computer in the role of tax accountant 



5 



Education is one of the most exciting areas for 
personal computer use, particularly for your 
TI-99/4A. The educational software packages 
available for your computer number in the hun- 
dreds — at levels from preschool to college. 
Programs are available for spelling, grammar, 
reading concepts, mathematics, history, music, 
foreign languages, and other subjects. Much 
of the educational software available comes in 
a question-and-answer drill format: you respond 
to questions posed on the screen, and the com- 
puter monitors your answers. Some programs 
take the form of interactive simulations: you are 
placed in a situation (say, the Battle of Gettys- 
burg) so that you can learn about the event. The 
wide array of educational software on the mar- 
ket for the TI-99/4A will continue to grow as the 
popularity of educational software increases. 

Games and hobbies also adapt to computeriza- 
tion. In addition to the video games you can 
play on your TI-99/4A, there are a number of 
thinking games and simulation games. Sim- 
ulations of popular sports such as football and 
soccer, along with common board games such 
as chess and checkers, can be played using the 
computer. 



6 



Your computer can even expand your horizons 
by tapping into information networks — with 
the use of a telephone. Information networks . 
offer the latest news, stock exchange prices, air- 
line schedules, electronic classified ads, and 
national restaurant and movie reviews. Some 
services of this type even offer electronic shop- 
j ping and banking. 

With appropriate software and peripherals 
(accessories), all of these applications are now 
I available to you. This text provides the informa- 
! tion you'll need to choose the right software 
• and accessories for whatever you want to do. 

Many people are under the impression that to 
use a home computer they have to become pro- 
grammers, but that is far from the truth. You'll 
find that using your computer is easier than you 
ever dreamed. For example, your computer uses 
plug-in cartridges as a form of software. All you 
have to do is insert the cartridge into a slot, and 
the computer is ready to perform. The software 
is easy to use because it presents you with a list 
of choices. By simply following the step-by-step 
instructions outlined on the screen, you'll find 
that commercial software packages require 
no programming knowledge at all. 



7 



If you want to learn programming, you have 
that option, too. The programming language 
called BASIC is built into your computer, allow- 
ing you to write your own programs and save 
them on cassette or floppy disk. The 16K mem- 
ory that is a standard feature of your TI-99/4A 
provides ample storage for the novice to inter- 
mediate programmer. And your computer is 
capable of using many additional programming 
languages, including Extended BASIC, Pascal, 
Logo, and Assembly Language. 

Whether you are a first-time computer owner 
or one who is trading up from a basic learning 
computer, you'll find that you have a powerful, 
expandable home computer in your TI-99/4A. 
The purpose of this text is to help you get max- 
imum use out of your new computer. 



8 



CHAPTER 2 

GETTING STARTED 



To get the most from your new computer sys- 
tem, you must take the time to become ac- 
quainted with its parts. Every system includes 
some basic components: the computer, a moni- 
tor or television set to connect to the computer 
as a means of display and software to use with 
the computer. In addition to these basic parts, 
you may have purchased some peripherals such 
as a set of joysticks, a cassette recorder or disk 
drive system, and the cables needed to connect 
these items to your computer. 

The heart of your computer system is the 
TI-99/4A Home Computer Console, which con- 
tains the keyboard, a slot for the use of cartridge 
software, and a built-in version of the BASIC 
computer programming language. In the box 
with your Home Computer Console is the Video 
Modulator (a TV adapter which allows you to 
connect the computer to a television set). Also 
packed with your computer should be two 
books: User's Reference Guide and Beginner's 
BASIC both supplied by Texas Instruments. A 
separate Power Supply that connects to the 
computer completes the basic computer system. 
Before you set up your computer, let's take a 
tour. 



9 



TI-99/4A computer (front view) 

On the front of the computer, at the right side, 
are the Power On switch and the Power Indica- 
tor Lamp. Sliding the Power On switch to the 
right turns your computer on. 



10 



TI-99/4A computer (right side view) 

On the right side of the computer is a slot that 
is covered by a sliding door. This slot houses the 
Expansion Connector. You'll use this connector 
to attach many peripherals (but more about that 
later). The door that covers the Expansion Con- 
nector should remain closed when the connec- 
tor is not in use. (And you should be careful not 
to touch the metal pins on the Expansion Con- 
nector; delicate circuits inside the computer can 
be damaged by static electricity if you touch 
these pins.) 



11 



TI-99/4A computer (left side view) 

On the left side of the computer is the Game 
Controller Port; it has nine little pins. This is 
where you plug in joysticks when you want 
to play games. 



T2 



TI-99/4A computer (rear view) 



On the rear of the computer you'll find three 
more connectors. The connector on the left 
rear of the computer, resembling the Game Con- 
troller Port, is where you attach the Cassette 
Recorder Interface Cable. Next, to the right, is a 
connector with four pins; here you plug in the 
Power Cord. Finally, on the right rear of the com- 
puter is a circular connector (with five pins). This 
is where you connect your video monitor or 
television set. 



13 



TI-99/4A computer (top view) 



Your TI-99/4A uses cartridge software (referred 
to as Solid State Software by .the manufacturer). 
The right half of the computer console contains 
a large access area for these cartridges. To the 
rear of the cartridge software access area is a 
series of ventilation slots. THESE SLOTS SHOULD 
NEVER BE OBSTRUCTED; they are necessary to 
maintain proper cooling of your computer when 
it is in operation. The area on the left side of the 
computer console is the keyboard. It resembles 
the keyboard of a normal typewriter, plus some 
special function keys. (Chapter 3 covers the 
functions of the keyboard in detail.) 



14 



Here are the components you need to set up 
your TI-99/4A computer. All these compo- 
nents (except the television) come with your 
computer: 

Video modulator 
Standard home color (or black- 
and-white) TV 
Power supply 



HOOK 

YOUR" 



[ING 

TI-9 1 



UP 

9/4i 



Place the computer console on a firm surface, 
with room for any accessories that you may 
have purchased. If you are using a television set 
as a monitor, you'll need a screwdriver to con- 
nect the computer to it. Unwrap the books in 
the cellophane wrapper. Between them you'll 
find some papers; you'll also find some strips of 
plastic (gray on the front and black on the back). 
These plastic strips are called overlays. One of 
the strips has some writing on it; place that strip 
on the computer console in the angled space 
just above the keyboard. 

Pick up the Power Supply that was packed with 
your computer. Insert the four-pin plug at the 
end of the Power Supply cable into the four-pin 
connector on the left rear of the computer. Plug 
the Power Supply into a standard 1 15-volt AC 
electrical outlet. As a safety precaution, you may 
want to unplug the Power Supply when you fin- 
ish using the computer (and replug it the next 
time). 

To link your computer to a television follow 
these steps: 



16 



STEP 1 

Turn the television set OFF. Loosen the screws 
on the VHF antenna terminals on your television 
set and remove the antenna cable. 



17 



STEP 2 

Pick up the Video Modulator that was provided 
with your computer system. Connect the Video 
Modulator Television Interface Cable to the VHF 
antenna terminals on the TV set. Tighten the TV 
set antenna screws. 



18 



STEP 3 

Connect the television VHF antenna cable to 
the Video Modulator antenna terminals 
and tighten the screws. 



STEP 4 

Locate the five-pin plug at the end of the Video 
Modulator's computer interface cable and insert 
it into the circular five-pin connector on the right 
rear of the computer. Be sure that the pins are 
properly aligned to the socket to avoid breaking 
the pins. Connect the plug firmly, but don't try 
to force it into position. 



20 



STEP 5 

Use the peel-and-stick adhesive tape on the rear 
of the Video Modulator to attach the modulator 
to your television set. 



21 



STEP 6 

In your area, television channel 3 or 4 should be 
unused. Place the channel select switch at the 
bottom of the Video Modulator in the unused 
channel position. Also set your television set to 
that channel. 



22 



STEP 7 

Set the switch at the top of the Video Modulator 
to the MODULATOR position. 



23 



If you are using the Tl Color Monitor, follow 
these steps: 

STEP 1 

Unpack the Tl Color Monitor, and locate the 
Color Monitor Video Cable supplied with the 
monitor. 



24 



STEP 2 

Locate the five-pin plug at the end of the Video 
Cable and insert it into the circular five-pin con- 
nector on the right rear of the computer. Be sure 
that the pins are properly aligned to the socket 
to avoid breaking the pins. Connect the plug 
firmly but don't try to force it into position. 



25 



STEP 3 

Locate the jacks marked "VIDEO" and 
"AUDIO" on the rear of the Color Monitor. 
Insert the plugs on the end of the Video Cable 
into these jacks. The plugs are different sizes, 
so you can't put them in the wrong places. 



26 




If you purchased Tl joysticks with your com- 
puter, follow these steps: Locate the nine-pin 
plug at the end of the joystick cable. Insert this 
plug firmly into the Game Controller Port on 
the left side of the computer. 



27 




If you are using a cassette recorder for program 
storage, follow these steps: 



STEP 1 

Obtain the Tl Cassette Recorder Interface Cable. 
This cable is not supplied with the computer; it is 
supplied with the Tl Cassette Program Recorder, 
or you can buy it separately if you want to use a 
different cassette recorder. 



28 



STEP 2 

Locate the nine-pin plug at one end of the 
Cassette Recorder Interface Cable. Insert this 
plug firmly into the jack on the left rear of the 
computer. 



STEP 3 

Locate the set of three plugs at the other end of 
the cable. The wires that lead to these plugs are 
color-coded (red, black, and white). 



30 



STEP 4 

Locate the jacks labeled MIC EAR (or ex- 
ternal speaker), and REM on your cassette 
recorder. 



STEP 5 

Insert the plug with the red wire into the record- 
er's microphone jack (labeled MIC). 



32 




STEP 6 

Insert the plug with the white wire into the 
recorder's earphone (or external speakerjjack 
(labeled EAR). 



33 



STEP 7 

Insert the plug with the black wire into the 
recorder's remote jack (labeled REM). 



34 



Now you're ready to turn on and use your com- 
puter. Turn on the Power On switch at the front 
of the computer. The red Power On lamp should 
light. (If the red Power On lamp does not light, 
check the Power Supply cable connection at the 
rear of the computer and make sure that the 
Power Supply is plugged into a working outlet.) 
Turn on your television set or Tl Color Monitor. 
Fine tune your television set for the best picture 
possible. If this image shown in the photograph 
on this page does not appear on your screen, 
check the cable connections between the com- 
puter and the TV set or monitor. 

If you have purchased any software cartridges 
with your computer, this is an excellent time to 
try one of the cartridges with your new com- 
puter. Insert the software cartridge into the car- 
tridge access slot on the right half of the com-, 
puter console. Press the cartridge firmly and fully 
into the access slot. The screen will clear, then 
display the Tl Color Pattern and the words, 
PRESS ANY KEY TO BEGIN. 



35 



Tl Color Pattern 



Press any key on the keyboard. A menu will 
appear on the screen, indicating that you should 
type the number I to select Tl BASIC, or type the 
number 2 to use the software cartridge that you 
have inserted. Your screen should look similar 
to this: 

TEXAS INSTRUMENTS 
HOME COMPUTER 

PRESS 

1 FOR Tl BASIC 

2 FOR THE ATTACK 



36 



GENERAL PLACEMENT AND CARE OF 
YOUR COMPUTER 

Find a convenient location for your new TI-99/ 
4A computer system. The computer console 
should be placed on a desk, table, or other flat 
surface that is elevated enough so that you can 
rest your hands comfortably on the keyboard. To 
provide the least amount of possible static inter- 
ference, the surface that you place the com- 
puter on should be nonmetallic. NEVER place 
the computer directly on top of a television set 
or video monitor. The heat generated by most 
monitors and television sets could damage your 
computer. The ventilation slots along the rear 
and at the top of the computer console should 
not be restricted or covered when the computer 
is turned on. 

You may want to consider obtaining a computer 
desk for your system. Many computer owners 
eventually expand their systems. If you decide to 
add the Peripheral Expansion System (described 
in Chapter 4), you will need an additional 12 
inches of space behind the computer. You may 
also need space for a printer, should you decide 
to purchase one. 

CLEANING 

Your computer does not require any special 
cleaning. When you want to clean the com- 
puter, use a damp, lint-free cloth. Never use 
commercial cleaners or other formulas on the 
computer surface. 



37 



TIPS TO REMEMBER WHEN YOUR 
SYSTEM LOCKS UP 

If you use your computer often, and particularly 
if you learn to program, a time will come when 
your computer appears to stop functioning. Sud- 
denly the keyboard will appear to ignore your 
requests for attention. But don't panic. All com- 
puters lock up at one time or another. 

If you are a programmer, you will find that this 
happens often, usually due to errors in the pro- 
gram. What has happened is known in com- 
puter lingo as a system crash, and it happens 
occasionally to everyone who uses a personal 
computer often. The best plan of action to fol- 
low if your system crashes is to proceed slowly 
while trying to find the cause. 

A system crash can occur for a number of ' 
reasons. A first check that you might want to 
make would be your computer's connections. 
Are all of the cables tight? If you were using 
cartridge software, is the cartridge fully inserted? 
If you were using a command that's used to 
print information on a printer, it is also a poten- 
tial trouble point. Your computer must hear a 
series of signals from your printer as it is printing. 
If a cable is loose and these signals aren't heard, 
the computer will appear to lock up as a 
result. 



38 



If your TI-99/4A is equipped with a disk drive, it 
can be a cause of a system crash. You should sus- 
pect this area of your system if the computer 
went haywire the moment you used a command 
to load or save information using the disk drive. 
The drive itself is not usually the cause of the 
problem; often, the floppy disk is defective or is 
the victim of mishandling. 

There are some tasks that you can perform 
routinely to minimize the bad effects of a system 
crash. If you are programming, you should use 
the SAVE CS1 command (on a cassette system) 
or the SAVE command (on a disk system) to save 
the information that you're using often. Doing 
so will minimize the amount of information you 
lose when system crash occurs. 

If your computer doesn't appear to be operat- 
ing normally the following troubleshooting 
guide may help you to isolate the cause of the 
problem. If the troubleshooting guide does not 
solve the problem, contact your dealer for 
assistance. 



39 



TROUBLESHOOTING 
GUIDE 



Problem 

Power indicator fails to light when the power 
switch is turned on 



Picture and/or sound fails 



Joysticks do not operate correctly 



Cassette recorder does not operate correctly 



Computer will not respond to input at the key- 
board; garbled characters or other erratic symp- 
toms are present 

40 



Correction 



Make sure the Power Supply is plugged firmly 
into the wall outlet and the Power Supply cord is 
firmly connected to the plug at the rear of the 
computer. 



Make sure the computer is turned on. Make sure 
the Video Modulator cables are properly con- 
nected and the TV set is tuned to the channel 
selected on the Video Modulator. 



Make sure the ALPHA LOCK key is in the UN- 
LOCKED (or up) position and the joystick cable 
is connected to the nine-pin connector on the 
LEFT SIDE of the computer (NOT the connector 
on the rear). 



Make sure the Cassette Recorder Interface 
Cable is connected to the nine-pin connector on 
the REAR of the computer (NOT the connector 
on the leftside). 



Turn your computer OFF. Wait five seconds or 
more. Turn the computer back on. If the problem 
persists, contact your dealer for assistance. 



41 



CHAPTER 3 

MEET THE KEYS 



Turn your computer on. And then turn on your 
TV set. Tune the TV set to the proper channel, 
if necessary and slide the switch on the Video 
Modulator to MODULATOR. The Tl Color 
Pattern should appear on the screen. 
SCREEN 1 

Take a good look at the keyboard. It resembles 
the keyboard that you might see on an ordi- 
nary typewriter, with one key for each letter of 
the alphabet and one key for each numeral (0 
through 9). There are also keys with punctua- 
tion marks and keys with words on them such as 
SHIFT and ENTER. In this chapter, we'll explain 
how each of these keys is used. 

Press any key on the keyboard and the screen 
will change. 
SCREEN 2 

Press the number 1 key and the screen will 
change again. 
SCREEN 3 



42 



PROMPT AND CURSOR 

On the screen, below the words Tl BASIC 
READY, you see an arrow-shaped character and 
a flashing block. These are two important screen 
characters: the prompt and the cursor. That 
arrow-shaped character is called the prompt in 
computer lingo. The prompt always shows you 
on what line the letters or numbers you type will 
appear. The flashing block is known as the cur- 
sor. The cursor will always show you where the 
very next character that you type will appear. 

The cursor is important in another way too; it 
shows you when your computer is waiting for 
you to provide some type of information. When 
the cursor is on the screen and flashing, your 
computer isn't doing any work. It's just sitting 
there, waiting for you to tell it what to do next. 

NOTE: In the photographs in this chapter, the 
cursor is a slightly lighter color than the letters 
and numbers shown on the screen. Because the 
cursor blinks on and off, it appears in a lighter 
color in photographs. On your "TV or monitor 
screen, the cursor is the same color as the letters 
and numbers whenever it blinks on. 



43 



SCREEN 1 
The Tl Color Pattern will appear each time 
you turn your computer on. 




SCREEN 2 
This screen follows the Tl Color Pattern. Press 
the 1 key to use Tl BASIC. 
44 



SCREEN 3 

Note the arrow-like prompt and the flashing 
cursor at the left edge of the screen. 



TYPE AWAY 



Now let's give your keyboard a try. Type any 
words or sentences you wish for a few mo- 
ments. Keep looking at your computer's screen 
as you type. What happens when you reach the 
edge of the screen and continue to type? 

Right! The letters continue on the very next line 
on the screen. 
SCREEN 1 

Now, press any letter (or number) key and hold 
it down for several seconds. What happens? 

Right again! The computer printed the letter (or 
number) over and over as long as you held the 
key down. This built-in feature of your computer 
is known as auto repeat 
SCREEN 2 

If you try to type more than four lines, you'll 
notice that any more letters you type won't 
appear, and the cursor won't move any far- 
ther on the screen. 
SCREEN 3 

To make the cursor move farther, you'll need to 
learn to use the ENTER key. 



46 



SCREEN 1 

When what you are typing is continued on 




SCREEN 2 

Holding down a key for several seconds 
causes the auto repeat of the character. 



THE ENTER KEY 




The ENTER key is located on the right edge, 
halfway down the keyboard. You use it to enter 
information into the part of the computer that 
actually does the thinking (or calculating). As 
you type, letters and numbers appear on the 
screen, but the computer doesn't actually think 
about what it should do with any of those 
characters until you press the ENTER key 



49 



Press the ENTER key now. What happened? The 
computer beeped at you, wrote * INCORRECT 
STATEMENT, and began a new line (with a 
prompt at the left). 
SCREEN 1 

Next type in about twenty letters — any letters 
you want — but do not put any spaces between 
the letters. Press the ENTER key. Your computer 
now responds with a different message, BAD 
NAME. 
SCREEN 2 

Now try typing in an instruction that your com- 
puter can follow. Type 

CALL CLEAR 

but don't press ENTER yet. (If you made a mis- 
take, press the ENTER key and try again.) Notice 
that the computer sits there, with the flashing 
cursor at the end of the line. The computer is 
waiting patiently for you to tell it to get started. 
SCREEN 3 

Now, press ENTER. What happened? 
Surprise! The entire screen turns blank, and 
the cursor appears at the bottom of the screen. 
SCREEN 4 

The CALL CLEAR command is used to clear the 
screen. But the computer didn't recognize the 
command until you pressed the ENTER key. 



50 





SCREEN 4 

The CALL CLEAR command produces a blank 
screen, with a prompt and a flashing cursor. 

52 



The computer recognizes only a very specific 
set of words. You'll learn about your computer's 
vocabulary if you delve into BASIC program- 
ming. For now, remember that your computer's 
ENTER key always tells the computer to act 
upon whatever information is in the line that 
you just typed. 

Even if you use a series of words or a command 
that is not in the computer's vocabulary the 
computer won't know anything is wrong until 
you press ENTER and it tries to interpret those 
words. To see what we mean, type 

THIS MAKES NO SENSE AT ALL 



53 



The sentence appears on the screen. 
SCREEN 1 

That sentence means nothing to the computer. 
Still, your computer doesn't care right now, 
because you haven't pressed ENTER yet. The 
computer won't try to translate those words 
into its language until you press ENTER. So, let's 
press ENTER! Now, the computer will read the 
sentence you just typed, discover that none of 
those words are in its vocabulary, and print out 
the message * INCORRECT STATEMENT, to tell 
you that it doesn't understand what you said. 
SCREEN 2 

Instead of INCORRECT STATEMENT, the com- 
puter displays BAD NAME if you type in a word 
that has more than fifteen characters and then 
press ENTER. 

Before starting the next exercise, type the words 
CALL CLEAR and press ENTER to clear the 
screen. 



54 



THE SPACEBAR 




SPACEBAR 

The long rectangular key at the very bottom of 
the keyboard is called the spacebar. If you're 
familiar with typing, you already know about 
the spacebar. It's used to add spaces between 
the words that you type. Let's try the spacebar 
with different words. Type the following sen- 
tence, pressing the spacebar once after each 
word to leave a space: 

THIS IS MY COMPUTER. 



56 



The sentence appears on the screen. 
SCREEN 1 

Like the other keys, the spacebar is a "repeat" 
key. This may come in handy at times, when you 
want to add large spaces between words. Try 
this now. Type the word 

LARGE 

The word appears after your sentence. 
SCREEN 2 

Then hold the spacebar down for a few seconds. 
When the cursor gets to the end of the line, it 
automatically wraps around to the beginning of 
the next line and continues on. 
SCREEN 3 

Now type the word 

SPACE 

The large gap caused by your holding down the 
spacebar may look strange in this case, but there 
may be times when you'll want a large space 
between words on the screen. 
SCREEN 4 

Before starting the next exercise, press ENTER, 
type the words CALL CLEAR, and press ENTER 
again to clear the screen. 



57 



THE LETTER KEYS 




LETTER keys 



,60 



One key for each letter in the alphabet is located 
on your keyboard. But they are not laid out in 
alphabetical order. Instead, the location of the 
keys follows what is known as the typewriter, or 
"QWERTY," format. QWERTY comes from the 
first six keys on the left in the top row of letters. 
If you are already a typist, then you are familiar 
with where each of the keys is located. If you 
are not a typist, you may wish to locate each let- 
ter of the alphabet on the keyboard now. 

First, press each letter key in the order they 
appear on the keyboard, starting with the top 
row. 

SCREEN 1 

Now try typing all the letters in alphabetical 
order. 

SCREEN 2 

Before starting the next exercise, press ENTER, 
type the words CALL CLEAR, and press ENTER 
again to clear the screen. 



61 




SCREEN 1 
The letter keys on the keyboard are not 
placed In alphabetical order. 




SCREEN 2 

You may have to practice to be able to find all 
of the keys In alphabetical order. 

62 



THE ALPHA LOCK KEY 




Your computer can create uppercase (capital) 
and lowercase (small) letters. On the lower left 
side of the keyboard, locate the key marked 
ALPHA LOCK. The ALPHA LOCK key causes all 
of the letters to be displayed as uppercase letters. 
The ALPHA LOCK key gets its name from the 
fact that it can be locked in the down position. 
Let's try using the ALPHA LOCK key. Press the 
ALPHA LOCK key until it locks in the down posi- 
tion. Now, type a few words, like this: 



63 



A FEW WORDS 



(Don't worry if you make a mistake; we'll learn 
how to fix mistakes a little later.) Your words 
appear on the screen. 
SCREEN 1 

Press the ALPHA LOCK key again (to "unlock" 
it) and again type 

A FEW WORDS 

See the difference? 
SCREEN 2 

The first A FEW WORDS you typed (in up- 
percase) is about twice as large as the second 
(which is in lowercase). The lowercase letters on 
the screen are not true lowercase letters. The 
TI-99/4A always represents a lowercase letter 
by displaying a character that is roughly half the 
size of the uppercase letter. 

There are two rules for using the ALPHA LOCK 
key: 1 ) when you use Tl Joysticks to play games, 
the ALPHA LOCK key must be unlocked, in the 
up position, and 2) when you are programming 
in BASIC, leave the ALPHA LOCK key locked, in 
the down position (because some commands in 
Tl BASIC require the use of capital letters). 

Before starting the next exercise, press ENTER, 
type the words CALL CLEAR, and press ENTER 
again to clear the screen. 

64 



SCREEN 1 

All of the letters displayed on the screen look 
like conventional uppercase letters. 




THE SHIFT KEYS 




On the lower left and lower right sides of the 
keyboard, locate the two keys marked SHIFT. 

Like the ALPHA LOCK key the SHIFT keys are 
used to type uppercase letters. The SHIFT keys 
have an additional function, however — one 
which the ALPHA LOCK does not perform: for 
every key on the keyboard which has two sym- 
bols on it (such as the key with the number 4 
and the dollar sign), the SHIFT key gives you ac- 
cess to the upper symbol. 
66 



Try typing various keys now (letters, numbers, or 
other symbols) with and without a SHIFT key 
depressed, and notice the results. 

First type all the letters in the top row of the 
keyboard without using a SHIFT key. Then type 
the same letters with a SHIFT key held down. 
SCREEN 1 

Hold down the spacebar until the cursor moves 
to the beginning of the next line. Now type all 
the number keys without using a SHIFT key. 
Then type the same keys with a SHIFT key held 
down. 
SCREEN 2 



Use the spacebar to move the cursor to the next 
line. Now type a few symbol keys without using 
a SHIFT key. Then type those keys again with a 
SHIFT key held down. 
SCREEN 3 

Before starting the next exercise, press ENTER, 
type the words CALL CLEAR, and press ENTER 
again to clear the screen. 



67 



SCREEN 3 

Other keys have two symbols on them as 
well. 



THE FUNCTION KEY 




FUNCTION key 




70 



At the bottom of the right side of the keyboard 
is a key marked FCTN (with a gray dot on the 
front). This is your FUNCTION key. The FUNC- 
TION key has a special purpose: it makes other 
keys on the keyboard perform more than one 
job. Using the FUNCTION key is similar to using 
the SHIFT key; you hold it down while you press 
another key By doing this, what happens on the 
screen is the result of the function of the key you 
typed with the FUNCTION key The special 
functions of the letter keys are indicated on the 
fronts of the keys. 

Let's try this to see how it works. First, hold the 
FUNCTION key and press the I key What char- 
acter appeared? 
SCREEN 1 

A question mark just appeared on the screen. 
Examine the front of the I key on the keyboard, 
and you will see the question mark symbol. 

Now while you hold the FUNCTION key press 
the R key and then the T key The left and right 
brackets appear. 
SCREEN 2 



71 




SCREEN 1 

Pressing the FUNCTION key with the I key 
creates a question mark on the screen. 



iiiiii 



SCREEN 2 

Pressing the FUNCTION key with the R and T 
keys creates the left and right brackets. 

72 



Now hold the FUNCTION key and press the P 
key to get a quotation mark. 
SCREEN 1 

Then hold the FUNCTION key and press the O 
key to get the apostrophe. 
SCREEN 2 

In each case, the character that's on the front 
of the key appears on the screen when you 
press the FUNCTION key with the letter key. In 
this manner, the keyboard of your TI-99/4A can 
create many more characters than there are 
keys. 

Most of the characters that you see on the front 
of the keys are used in special cases, such as in 
typing a letter when using word processing soft- 
ware with your TI-99/4A. The UP and DOWN 
arrow keys are used in an editing mode during 
BASIC programming; that is a more complex pro- 
gramming function that is detailed in your Tl 
BASIC Handbook. You'll need these keys only 
if you become extensively involved in BASIC 
programming. 



73 



The special functions of the keys in the top row 
are indicated on the plastic overlay The FUNC- 
TION key is like an "international translator" 
who, when called into action, changes the very 
language of your keyboard. To help you keep 
track of this new language, you have placed the 
strip of words above the number keys on your 
keyboard. Don't worry about just what the 
names that make up this new language mean 
right now. We'll explain these functions when 
we discuss each of the number keys. 

Before starting the next exercise, press ENTER, 
type the words CALL CLEAR, and press ENTER 
again to clear the screen. 



74 




SCREEN 1 



Pressing the FUNCTION key with the P key 
creates a quotation mark. 




SCREEN 2 

Pressing the FUNCTION key with the O key 
creates an apostrophe. 



THE LEFT AND RIGHT 
ARROW KEYS 




LEFT ARROW and RIGHT ARROW keys 




When you use the spacebar, the cursor moves to 
the right. But suppose you make a mistake or 
want to add a letter or word in the middle of a 
sentence. Perhaps you decide you want to erase 
a letter or an entire word. You can add and erase 
letters and words with your computer. But to do 
so, you must first be at the place in the sentence 
where you want to add or remove characters. 

Let's find out how to do this. Type the sentence 



76 



THIS IS MY COMPUTER. 

Right now, the cursor is near the end of the line. 
SCREEN 1 

Look at the S key and the D key. On the front of 
these keys you see arrows that point to the 
left and to the right. These keys, used with 
the FUNCTION key move the cursor back 
and forth. Let's try it! 

Hold the FUNCTION key and press the S key 
nine times. The cursor is now on top of the let- 
ter C in COMPUTER (if you had a period at 
the end of your sentence ). 
SCREEN 2 

Hold the FUNCTION key and press the D key 
six times. Your cursor is now positioned on top 
of the letter E. 
SCREEN 3 

By using the S key as a left arrow key and using 
the D key as a right arrow key you can move 
the cursor to any spot within a line of typing. 
You can think of using the left and right arrow 
keys to move the cursor as being similar to lifting 
a pencil from one place on a sheet of paper and 
placing it at another spot on that same sheet of 
paper. 

Before starting the next exercise, press ENTER, 
type the words CALL CLEAR, and press ENTER 
again to clear the screen. 



77 



SCREEN 1 
The LEFT ARROW and RIGHT ARROW keys let 
you move the cursor back and forth within a line. 




SCREEN 2 
Using the FUNCTION key with the S key 
moves the cursor to the left. 



78 




SCREEN 3 

Using the FUNCTION key with the D key 
moves the cursor to the right. 



79 



THE CONTROL KEY 
AND NUMBER KEYS 




CONTROL key • NUMBER keys 




80 



THE CONTROL KEY 

The key marked CTRL, to the left of the spacebar, 
is the CONTROL key it works like the FUNCTION 
key — you hold it down with another key on the 
keyboard and the combination tells the com- 
puter to do something special. But the control 
functions are not indicated on the keyboard 
because they change. You'll only use control 
functions with special software programs, and 
the specific software program will provide in- 
structions for their use (and usually a handy 
reference card to tell you which keys do what). 

THE NUMBER KEYS 

The number keys in the top row operate a little 
differently from the letter keys. There are no up- 
percase numbers. Instead, each number key 
contains two characters. One (in the lowercase 
position) is a number, and the other (in the up- 
percase position) is a symbol of some sort. You 
type the number key alone to produce the num- 
ber on the screen. To produce the symbol that is 
above the number, you hold the SHIFT key and 
type the number key. 

Remember how this works? Hold the SHIFT key 
down, and type the number keys from one 
through nine and then zero. Your screen will 
show the symbols on the upper part of the keys. 
SCREEN 1 

Before starting the next exercise, press ENTER, 
type the words CALL CLEAR, and press ENTER 
again to clear the screen. 



81 



Pressing the SHIFT key with a number key 
creates a symbol on the screen. 



82 



THE 1/! KEY- 
DELETE FUNCTION 




The 1 /! key fs at the left end of the top row of 
keys. If you simply press the key, a numeral J 
appears on the screen. Now hold the SHIFT key 
and press the 1 /! key. The exclamation mark - 
appears next to the numeral. 
SCREEN 1 

The special function of the I /! key is indicated 
on the label just above the key. The letters DEL 
stand for DELETE. By holding down the FUNC- 



83 



TION key and the 1/1 key, you can delete (re- 
move) characters that you don't want in a line. 
The DELETE key operates much like an eraser 
on a sheet of paper. The DELETE key has some 
advantages over a normal eraser, however. It's 
much neater — in addition to not leaving a mess 
after use, the DELETE key won't leave blank 
spaces where you've erased mistakes. 
Let's try using the DELETE key. Type 

THIS IS MY OLD COMPUTER. 

Your sentence appears. 
SCREEN 2 

Now use the left arrow key to move the cursor 
to cover the letter O in the word OLD. 
SCREEN 3 

Now, hold the FUNCTION key down, and press 
the I /I key four times. What does our sentence 
say now? 
SCREEN 4 

By using the DELETE key, you've deleted the 
word OLD. Each time you press DELETE, the 
character (or space) on which the cursor rests is 
erased, and all of the letters to the right of the 
cursor move to the left by one space. This auto- 
matically takes care of the space that was occu- 
pied by the deleted character. 

Before starting the next exercise, press ENTER, 
type the words CALL CLEAR, and press ENTER 
again to clear the screen. 



84 



SCREEN 1 

Press the 1/1 key twice, once by itself and 




SCREEN 2 

To delete the word OLD, first move the cursor 
to the left... 



85 



THE 2/a KEY- 
INSERT FUNCTION 




The 2/@ key is located in the top row of keys, 
just to the right of the 1 /! key If you simply press 
the key a numeral 2 appears on the screen. 
Now hold the SHIFT key and press the 2/@ key 
That strange-looking symbol that just appeared 
on your screen is an abbreviation for the word 
AT 

SCREEN 1 



87 



The special function of the 2/@ key is indicated 
on the label just above the 2/@ key. The letters 
INS stand for INSERT. Holding down the FUNC- 
TION key while depressing the 2/@ key turns 
the 2/@ key into an INSERT key You'll use the 
FUNCTION key and the 2/@ key to insert 
characters into a line that you have already 
typed. 

Let's give this a try? Type 

THIS IS MY COMPUTER. 

Your sentence appears on the screen. 
SCREEN 2 

Now use the left arrow key to move the cursor 
to cover the C in the word COMPUTER. 
SCREEN 3 



88 



SCREEN 1 

Press the 2/@ key twice, once by Itself and 
once with the SHIFT key. 




SCREEN 2 

To Insert a word between MY and COM- 
PUTER, move the cursor left... 




90 



2/@ key 



2 



Now, hold the FUNCTION key down and press 
the 2/@ key You won't see any difference on 
the screen, but your computer is now in the in- 
sert mode. Type the word NEW and press the 
spacebar once. What does the sentence say 
now? 
SCREEN 1 



91 



By using the INSERT key, you Ve inserted new 
text into an existing line. Notice that as you in- 
sert the new text existing words move to the 
right to create room for the new characters. 



You will stay in the insert mode until you use the 
arrow keys to move your cursor in either direc- 
tion. To see how this works, hold the FUNC- 
TION key down and press the left arrow key 
until the cursor is over the letter N in the word 
NEW. 

SCREEN 2 

Now, type the word OLD. 

Notice what happened! Since you are not in the 
insert mode any longer, the word OLD was not 
inserted between words. Instead, it simply re- 
placed the word NEW as you typed. 
SCREEN 3 

Remember, once you are in the insert mode, the 
characters that you type are added to your orig- 
inal text; when you are not in the insert mode, 
any characters that you type will replace the 
original text. 

Before starting the next exercise, press ENTER, 
type the words CALL CLEAR, and press ENTER 
again to clear the screen. 



92 




SCREEN 1 

The FUNCTION and 2/@ keys combined allow 
you to Insert words. 




SCREEN 2 
Moving the cursor turns off the Insert mode. 



93 



SCREEN 3 

With the insert mode off, any new characters 
you type replace whatever was there before. 



94 



THE V# KEY- 
ERASE FUNCTION 




The 3/# key is located in the top row of keys, 
just to the right of the 2/@ key If you simply 
press the key a numeral 3 appears on the 
screen. Now hold the SHIFT key and press the 
3/# key Your screen shows the # symbol (which 
means number). 
SCREEN 1 



95 



The special function of the 3/# key is indicated 
on the label just above the 3/# key. Since the 
DELETE key can be thought of as an eraser, you 
may wonder about the ERASE function of the 
3/# key Well, the 3/# key can also be likened 
to an eraser — it's just a much bigger eraser! 
Want to see what we mean? 

Try it on for size. Again, type in the sentence 

THIS IS MY COMPUTER. 
SCREEN 2 



Hold the FUNCTION key down, and press the 
3/# key. How much text was erased? 
SCREEN 3 

Imagine that! The entire sentence vanished, and 
the cursor is sitting next to the prompt. The 
ERASE function will always erase any characters 
that you've typed on a line. 



96 




SCREEN 1 

Press the 3/# key twice, once by itself and 
once with the SHIFT key. 




SCREEN 2 

When you press the FUNCTION key with the 
3/# key... 

97 



SCREEN 3 
...the whole line disappears! 



98 



THE 4/$ KEY- 
CLEAR FUNCTION 




The 4/S key is located in the top row of keys, just 
to the right of the 3/# key If you simply press 
the key a numeral 4 appears on the screen. 
Now hold the SHIFT key and press the 4/S key 
Your screen shows the $ symbol (which means 
dollars). 
SCREEN 1 

The special function of the 4/S key is indicated 
on the label just above the 4/S key By holding 



99 



down the FUNCTION key and the 4/S key you 
command the computer to clear the screen, to 
stop a BASIC program that is running on the 
computer. 

Right now, it's difficult for you to see how this 
key would work, because you're not running a 
BASIC program on your computer. But we'll fix 
that! 

First press ENTER so you can start your program 
on a new line. (Don't worry if a BAD NAME 
message appears when you press ENTER.) 

Now type this sentence, just as it is shown: 

10 PRINT 1234567890 

(If you make any mistakes, you should now 
know how to correct them! Just move the cur- 
sor back to the incorrect character, and retype 
the correct character.) When you've finished 
typing the line, press the ENTER key. 
SCREEN 2 

Next, type the following sentence: 

20 GO TO 10 

Then press ENTER again. 
SCREEN 3 

You've just created a simple BASIC program. 



100 




SCREEN 2 

This is the first ilne in your very first computer 
program. 



101 




SCREEN 3 

With this second line, you have completed 
your program. To see what It does... 



102 



Now type the word RUN. 
SCREEN 1 

Then press the ENTER key. What's the result of 
your program? 
SCREEN 2 

Your computer takes off, rapidly showing the 
numbers across the screen from top to bottom. 
When you're tired of watching your computer 
repeat this mindless task, try typing a letter or 
number on the keyboard. Try pressing the space- 
bar. Try typing STOP or ENOUGH or any word 
you like. What happens? 

Absolutely nothing! Your computer is ignoring 
you as it busily prints rows of numbers on the 
screen. How can you get the computer to stop 
this operation? 

You could pull the plug out of the wall outlet, 
but it's not necessary to take such drastic action. 
It's times like these when the CLEAR key comes 
in handy. Hold the FUNCTION key down and 
press the 4/ $ key. The computer will beep, and 
your screen will show 

* BREAKPOINT AT 20. 



103 




...and press ENTER. The screen will be mov 
ing very quickly. 

104 



You have stopped the program from running. 
SCREEN 3 



Any time that you are running a BASIC program, 
you can interrupt it by using the CLEAR key. Us- 
ing the CLEAR function is like placing a stop sign 
in front of a moving computer! It forces the com- 
puter to come to a screeching halt. 

Before starting the next exercise, type CALL 
CLEAR and press ENTER to clear the screen. 




SCREEN 3 

By pressing the FUNCTION key and the 4/$ 
key at the same time, you stop the program. 



105 



THE 5/0/o KEY- 
BEGIN FUNCTION 




The 5/% key is located in the top row of keys, 
just to the right of the 4/S key. If you simply 
press the 5/% key a numeral 5 appears on the 
screen. Now hold the SHIFT key and press the 
5/% key. The screen displays the percent symbol 
(%). 

SCREEN 1 



106 



The special function of the 5/% key is indicated 
on the label just above the 5/% key. The BEGIN 
command is used only with certain software 
packages (or in BASIC programming); if you 
press the BEGIN key now, the computer will 
not respond at all. 

Before starting the next exercise, press ENTER, 
type the words CALL CLEAR, and press ENTER 
again to clear the screen. 




SCREEN 1 

Press the 5/% key twice, once by itself and 
once with the SHIFT key. 



THE 6/A KEY- 
PROCEED FUNCTION 




The 6/a key is one of four number keys that 
have special meaning when used in certain 
ways during BASIC programming. These four 
keys are the 6/a key for the exponent sign 
(a ), the 8/* key for the asterisk, the 9/( key for 
the left parenthesis, and the 0/) key for the right 
parenthesis. Let's discover what is meant by 
these symbols. 



108 



First, the 6/a key. Press the key by itself and a 
numeral 6 appears on the screen. Now hold the 
SHIFT key and press the 6/a key. The screen 
displays the exponent sign ( a ). 
SCREEN 1 

The exponent symbol, or SHIFT key and the 
numeral 6, tells the computer to raise a number 
to the power of another number. This is easier to 
demonstrate than it is to explain, so let's try it. 
You may already know that 6 2 = 36. The num- 
ber 2 indicates that the number 6 is raised to the 
power of 2. The exponent symbol on your com- 
puter can be used to perform the same kind of 
calculation! First, press the ENTER key to begin 
a new line. Now type 

PRINT 6 a 2. 

and your problem appears on the screen. 
SCREEN 2 

Next, press the ENTER key. Notice your compu- 
ter's answer (36) is displayed on the screen. 
SCREEN 1 



109 




SCREEN 1 

Press the 6/ A twice/once by itself and once 
with the SHIFT key. 




SCREEN 2 



The caret Indicates that an exponent 
follows it. 



110 



SCREEN 3 

PRINT tells the computer to perform the 
equation and display the answer. 



6/A key 




The exponent symbol can be used to calculate 
numbers raised to various powers. Type 

PRINT 14 a 6 

and the problem appears on the screen. 
SCREEN 1 



112 



Now press ENTER. Your computer's answer of 
7529536 shows that your computer can handle 
fairly large numbers! 
SCREEN 2 

Now, try this: type 

PRINT 9999 A9999 

and see this problem appear. 
SCREEN 3 

Now press ENTER. Your computer's message, 

* WARNING: 
NUMBER TOO BIG 

shows that even computers have limits! 
SCREEN 4 

The special function of the 6/ a key is indicated 
on the label just above the 6/a key The PRO- 
CEED command (abbreviated PROC'D) is used 
only with certain software packages (or in 
BASIC programming); if you press the PROCEED 
key now, the computer will not respond at all. 

Before starting the next exercise, type CALL 
CLEAR and press ENTER to clear the screen. 



113 



>6~ 



6~2 



>print 9999^9999 
SCREEN 3 

The computer can work with even very large 
numbers... 




Sprint 14^6 
7529536 

>print 9999^9999 

* mm** 



o ..- K „R TOD BIS 
9 . 99999E+** 



SCREEN 4 
...but not too large I 



THE 7/& KEY- 
AID FUNCTION 




The 7/& key produces the numeral 7 when 
pressed by itself; it produces the ampersand 
symbol (&) when the SHIFT key is held 
down. 
SCREEN 1 



116 



The ampersand symbol is not used for any 
special functions, but may be useful in normal 
typing of text. 

The special function of the 7/& key is indicated 
on the label just above the 7/& key The AID 
command is used only with certain software 
packages; if you press the AID key now, the 
computer will not respond at all. 

Before starting the next exercise, press ENTER, 
type the words CALL CLEAR, and press ENTER 
again to clear the screen. 




SCREEN 1 

Press the 7/& key twice, once by itself and 
once with the SHIFT key. 



117 



THE 8/* KEY- 
REDO FUNCTION 




The 8/* key produces the numeral 8 when 
pressed by itself; it produces the asterisk symbol 
(*) when the SHIFT key is held down. 
SCREEN 1 



118 



The asterisk is used to tell the computer to multi- 
ply numbers. In everyday writing, we use the 
letter x to represent multiplication. Humans, 
therefore, understand the statement 4x2 = 8. 
But to the computer the letter x is just that — a 
letter x. The computer can't tell whether we 
want x to represent the letter x, or whether we 
want x to represent multiplication. So the com- 
puter uses the asterisk for multiplication instead. 
Press ENTER to start on a new line. Then type 

PRINT 4*2 

and your problem appears on the screen. 
SCREEN 2 

Then press the ENTER key. The answer (8) 
appears on your screen, as the computer calcu- 
lates the product of 4 x 2. 
SCREEN 3 

The special function of the 8/* key is indicated 
on the label just above the 8/* key The REDO 
command is used only with certain software 
packages (or in BASIC programming); if you 
press the REDO key now, the computer will not 
respond at all. 

Before starting the next exercise, type CALL 
CLEAR and press ENTER to clear the screen. 



119 




SCREEN 1 

Press the 81* key twice, once by Itself and 
once with the SHIFT key. 




SCREEN 2 

The asterisk acts as a multiplication sign. 
120 




SCREEN 3 

PRINT tells the computer to multiply the num- 
bers and display the answer. 



121 



THE y( AND 0/J KEYS 




Press the 9/( key alone to get the numeral 9. 
Hold the SHIFT key and press the 9/( key to see 
the symbol for the left parenthesis appear on 
your screen. Press the 0/) key alone to get the 
numeral 0. Hold the SHIFT key and press the 
0/) key and the right parenthesis symbol will 
appear. 
SCREEN 1 



122 



The parentheses keys are important in complex 
math problems to tell the computer which part 
of a problem to perform first. You can demon- 
strate this on your system now. 

First, press ENTER to start a new line. Now, type 

PRINT 2 + 2*4 

and press ENTER. The computer will calculate 
and display its answer ( 10) on the screen. 
SCREEN 2 

Now, type 

PRINT(2 + 2)*4 

and be sure to include the parentheses. 
SCREEN 3 

Now press ENTER. What happens? 
Strange, you say! This time, the computer 
printed a different answer (16). 
SCREEN 4 

Actually, the computer is correct in both cases. 
The first time, it multiplied 2 by 4 to produce 8, 
then added 2 to get the sum of 10. In the second 
problem, the computer performed the calcula- 
tion that was inside the parentheses first: it 
added 2 and 2 to get the sum of 4, then multi- 
plied that sum by 4 to get a final answer of 16. 

Before starting the next exercise, type CALL 
CLEAR and press ENTER to clear the screen. 

123 




SCREEN : 
PRINT tells the computer to perform the 
equation and display the answer. 
124 




SCREEN 3 

Add parentheses to the same equation... 




SCREEN 4 

...and you get a different answerl 



125 



THE PLUS/ 
EQUALS KEY 




While we are on the subject of math, let's exam- 
ine the final key on the top row, the +/= key. It 
is used for calculations. Pressing this key alone 
creates the symbol = . Holding the SHIFT key 
while pressing this key produces a + . 

You'll use the + in addition problems, and there 
is no limit to the number of times it can be used. 
Type 



126 



PRINT2 + 4 + 56 + 3 + 1010 



and press ENTER. Your computer displays its 
answer (1075) after it performs the entire 
calculation. 
SCREEN 1 

The special function of the + / = key is indicated 
on the label above the +/= key. By holding 
down the FUNCTION key and the +/= key 
you command the computer to quit. Try it and 
see what happens. 

It may have come as a surprise; your screen 
turned solid blue (if you're using a color set), the 
computer beeped, and the Tl Color Pattern reap- 
peared on the screen. 
SCREEN 2 

Now, press any letter on the keyboard. You'll see 
the message 

PRESS 1 FOR Tl BASIC 

appear on the screen. 
SCREEN 3 

Type the number 1. Now, the message 
Tl BASIC READY 

will appear, and you are back in the computer's 
BASIC programming mode. 
SCREEN 4 



127 




SCREEN 2 

You command the computer to QUIT by pressing 
the SHIFT and +/= keys at the same time. 

128 



TEXRS INSTRUMENTS 
HOME COMPUTER 
PRESS 

lo'FdR TI BASIC 




SCREEN 3 

The prompt and the cursor reappear, and 
you're ready to get back to work. 



THE SLASH/ 
HYPHEN KEY 




You Ve seen characters used for addition and 
multiplication, but what about subtraction and 
division? Locate the SLASH/HYPHEN key directly 
above the ENTER key. 

By pressing the SLASH/HYPHEN key alone, you 
will create the slash symbol (/). In normal text, 
you can use this symbol to separate words, just 
as we did in describing the name of this key But 
you can also use the slash symbol to tell the 



130 



computer to divide one number by another. 
Now, you can try using the slash symbol for divi- 
sion by typing the following: 

PRINT 12/2 

The division problem appears on the screen. 
SCREEN 1 

Press ENTER, and the answer (6) appears. To the 
computer, the statement PRINT 12/2 is the same 
as the statement 12 -r 2 = is to you and me. 
SCREEN 2 

On the other hand, we can hold the SHIFT key 
and type the SLASH/HYPHEN key to create the 
hyphen symbol. If you're typing normal text, you 
can use the hyphen between words. In math 
calculations, the hyphen symbol becomes the 
computer's subtraction (minus) symbol. Try this: 

PRINT 800-250 

The subtraction problem now appears. 
SCREEN 3 

Press ENTER and the answer of 550 will be dis- 
played on your screen. 
SCREEN 4 

This key does not have any special functions. 

Before starting the next exercise, type CALL 
CLEAR and press ENTER to clear the screen. 



131 




SCREEN 2 

PRINT tells the computer to divide the 
numbers and display the answer. 

132 



SCREEN 3 

The hyphen acts as a minus sign. 




SCREEN 4 

PRINT tells the computer to subtract the num- 
bers and display the answer. 



THE PUNCTUATION 
MARK KEYS 



COLON/SEMICOLON key • COMMA/LESS THAN key • 
PERIOD/GREATER THAN key 












mmSm 









The :/; key, the ,/< key and the ./> key all oper- 
ate in a fairly standard way If you hold the 
SHIFT key down while typing any of these keys, 
the symbol on the upper half of the key is pro- 
duced. If you type the key without holding the 
SHIFT key the symbol on the lower half of the 
key is produced. 



134 



Hold the SHIFT key and press the ./> key. You'll 
see the symbol that's at the top of the key pro- 
duced on your screen. Release the SHIFT key 
and press the ./> key again. This time, you'll see 
the period appear on your screen. 
SCREEN 1 

Now try pressing the ,/< key first with the 
SHIFT key and then without. 
SCREEN 2 



Now press the :/; key first with SHIFT then with- 
out SHIFT. 
SCREEN 3 

The symbols produced by the ./> and ,/< keys 
when the SHIFT key is held are called the 
greater than and less than symbols. You'll use 
the greater than and less than symbols often if 
you write your own BASIC programs. 



135 




SCREEN 3 

Press the :/; key twice, first with the SHIFT 
key and then without it. 



137 



BASIC PROGRAMMING 



Now, let's take a look at the language that your 
computer speaks. It is called BASIC, and it is not 
the mystery that many people suspect it to be. 
BASIC is an easy-to-use computer programming 
language that uses English words to control the 
computer. The best proof of BASIC'S ease of use 
lies in the fact that you've been using it through- 
out this chapter! Words like PRINT, GOTO, 
RUN, and CALL CLEAR are BASIC commands 
that tell the computer to perform a certain task. 

Think of your computer as an electronic calcula- 
tor. A calculator doesn't possess any intelligence 
when you first turn it on. Instead, it stares blank- 
ly back at you and waits for you to tell it what to 
do. It's the same with your computer! Whenever 
you type a command that tells your computer to 
do a certain task, you are programming it, just as 
you are programming a calculator when you 
press its keys. What makes your computer more 
powerful than a calculator is its ability to remem- 
ber what you tell it. The computer has a power- 
ful memory that stores various types of informa- 
tion until they are needed. 



138 



So far, we haven't made much use of your com- 
puter's memory because we have been giving 
the computer immediate commands to carry out. 
For instance, when you told your computer to 
PRINT a word, it would print that word on the 
screen immediately and then forget it. But, you 
can give your computer the power of total re- 
call! All you need to do is use what is known as a 
line number — which is simply a number at the 
beginning of a line of information. The computer 
uses line numbers as a means of remembering 
what it should do next. 

When a collection of line numbers and lines are 
typed into the computer, that collection of 
information is called a program. A program is 
simply a series of steps which explain what your 
computer should do. 



139 



A SIMPLE PROGRAM 



MAKE YOUR COMPUTER 
A CALCULATOR 

Let's try a simple program now. First, if you have 
anything on your screen, press ENTER to start 
on a new line. Now type the word NEW and 
then press the ENTER key. The NEW command 
clears the computer's memory and displays the 
Tl BASIC READY message on the screen. (It 
seems to do the same thing as the CLEAR key, 
but the CLEAR key only clears the screen, not 
the memory.) 

Now, type the following, and don't forget to 
press ENTER at the end of each line! (Don 't be 
concerned if a program line runs over onto the 
next line. Just press ENTER when you're done 
typing each numbered program line.) 



10 CALL CLEAR 

20 PRINT "THIS PROGRAM WILL" 
30 PRINT "MULTIPLY TWO NUMBERS." 
40 PRINT "WHAT IS THE FIRST NUMBER?" 
50 INPUT A 

60 PRINT "WHAT IS THE SECOND NUMBER? 
70 INPUT B 
80C = A*B 

90 PRINT "THE ANSWER IS" 
100 PRINT C 



140 



The program lines now appear on your screen. 
SCREEN 1 



Now, type the word RUN. 
SCREEN 2 

Then press the ENTER key. The RUN command 
tells the computer to read the program. What do 
you see? 
SCREEN 3 

The computer wants you to give it a number, so 
press a number key and then press ENTER. 
SCREEN 4 



141 




SCREEN 2 

RUN is the command that will start the pro- 
gram. 

142 




SCREEN 3 

Pressing the ENTER key starts the program. 




SCREEN 4 

We chose the number 3 as our first number. 



143 



Now it wants another number, so press another 
number key. 
SCREEN 1 



Press ENTER again. Presto! The computer multi- 
plied the numbers and is showing you the 
answer— just like a calculator. 
SCREEN 2 



144 



SCREEN 1 

We chose the number 9 as our second number. 




SCREEN 2 



As soon as you entered the second number, 
the computer displayed the answer. 

145 



Now, type the word LIST. 
SCREEN 3 

Then press the ENTER key. The LIST command 
tells the computer to display on the screen all of 
the commands in the program. You will see the 
program displayed on the screen, just as you en- 
tered it. 
SCREEN 4 

Take a close look at this program. The numbers 
from 10 through 100 are the line numbers. Each 
line number is followed by a word or group of 
words that form a BASIC command. To run the 
program the computer begins with the smallest 
line number and performs the job that it is told 
to do by that particular line. Then it proceeds to 
the next line and follows the instructions given it 
by that line. The computer continues to perform 
the steps outlined in each line of the program. 
Once the computer runs short of work to do (in 
this case, after line 100), it assumes that it has 
finished running the program. That's when it 
displays the word **DONE**. 

Do not clear your screen and do not turn off 
your computer at this time. Go on to the next 
exercise. 



146 



SCREEN 3 

LIST tells the computer to display the com- 
mands In the program. 



T IS THE FIRST NUM ' " -i 

IS THE SECOND NUflit 
IS 



THE ANSWER 
27 

DONE 

>LIST 

10 CALL CLEAR 

IS EKIHI THIS 
30 PRINT "multiply two 

40>RINT 

NUMBER? * 

§8 I NPtJT R 

60 PRINT "UHflT IS THE 

INPUT B 



Pi 



ft #3 



kr% 'BINT "THE 

>0 PRINT C 




ANSWER IS 



SCREEN 4 
Examine the program listing carefully. 



147 



SOME BASIC 
COMMANDS 

You have used one BASIC command a number of 
times— PRINT. Whenever the computer sees the 
word PRINT, it will print (display on the screen) 
the information that follows the word PRINT. If 
the information begins and ends with quotation 
marks ("THIS PROGRAM WILL"), the computer 
prints the information exactly as you typed it. If 
the information is not enclosed in quotation 
marks, the computer will assume that you are 
using the word or letter following the PRINT 
command to represent a number, and the com- 
puter will print that number. 

You also used a command called INPUT in this 
program. The INPUT command causes the com- 
puter to print a question mark, and the com- 
puter then waits for you to provide some type of 
information. Line 50 and line 70 of the program 
use INPUT commands to store the numbers to 
be multiplied. You use INPUT commands in a 
program in which there is information that you 
will want to change every time you run it. 



148 



And you used the LIST command. The word LIST 
tells the computer to display any program that is 
stored in its memory LIST can be very helpful if a 
program does not operate properly and you 
want to examine the program to see if you have 
made any typing errors. 

If you enter a very long program, you will dis- 
cover that when you use LIST, parts of the pro- 
gram race past the top of the screen so quickly 
that you cannot see those parts of the program. 
There is a solution to this problem. You can LIST 
parts of a program by entering specific line 
numbers. 

Type 

LIST 10-50 



149 



The command appears on the screen. 
SCREEN 1 

Now press ENTER. 

Your computer now lists lines 10 through 50. 
SCREEN 2 

Now, type 

LIST 60-80 

The new command appears. 
SCREEN 3 

Then press the ENTER key. 

This time, your computer lists lines 60 through 

80. 

SCREEN 4 



150 




SCREEN 1 

UST followed by line numbers tells the com- 
puter to fist only those programs lines... 




SCREEN 2 

...as soon as you press ENTER. 

151 




152 



COLOR COMMANDS 
SOUND COMMANDS 

You may want to try using your computer's color 
and sound capabilities with BASIC commands. 
The TI-99/4A can use a variety of sound and 
color commands that can add musical and visual 
effects to your programs. You can see an exam- 
ple of the color commands available by trying 
this simple program. 

First type NEW and press the ENTER key to 
clear the program that we just used from the 
computer's memory. 

Now, type the following program (and don't 
forget to press ENTER after you finish typing 
each line): 

10FORX=1 TO 16 

20 CALL CLEAR 

30 PRINT "THE NUMBER IS" 

40 PRINT X 

50 CALL SCREEN(X) 

60FORY= 1 TO 100 

70 NEXTY 

80 NEXT X 

Check your work to be sure there are no errors. 
SCREEN 1 

Now type the word RUN and press the ENTER 
key What's the result? 

153 



Your screen turned a series of colors as the pro- 
gram caused the computer to display all sixteen 
of its screen colors (including solid black, which 
may have caught you by surprisel). 
SCREENS 2 AND 3 

Do not clear your screen and do not turn off 
your computer at this time. Go on to the next 
exercise. 

Now, let's try your computer's "voice" by mak- 
ing a simple change to the program that is in the 
computer's memory. Type the following line: 

45 CALL SOUND( 1 00, 1 10*X,2) 

Then press ENTER. 
SCREEN 4 

Now, type RUN and press the ENTER key. 
This time, you heard sixteen different tones from 
your TV set speaker as it displayed the colors. 

There are many other BASIC commands that you 
can use with the TI-99/4A This introduction was 
designed to provide an idea of how simple 
BASIC programming can be. If you decide to 
learn more about BASIC, a beginner's BASIC 
manual comes with your computer. If you later 
want to learn more advanced programming, you 
may want to purchase a more detailed BASIC 
reference text. BASIC programming is just one of 
the many ways that you can enjoy using your 
TI-99/4A. 



154 




SCREEN 3 
This Is number 14. 




SCREEN 4 

Type this additional line Into your program 
and you will be ready for sound and color. 
156 



CHAPTER 4 

PERIPHERALS — 
EXPANDING YOUR 
SYSTEM 

Your TI-99/4A computer is the heart of your 
computer system, but you still need some pe- 
ripherals (accessories) to make your system com- 
plete. Peripherals are your computer's way of 
communicating with the outside world. They are 
the computer's eyes, ears, and voice, and they 
are necessary parts of any home computer sys- 
tem. For example, you use your television set as 
a peripheral to display the information from your 
computer. 

Peripherals available for your TI-99/4A range 
from relatively inexpensive cassette recorders 
and joysticks for games to expansion systems 
with additional memory and multiple disk drives. 
It's helpful to know why peripherals are needed 
and what they can do for you. 

"Which peripherals should I buy?" is a question 
many new computer owners ask. There is no 
standard answer to this question, just as there is 
no standard answer to the question "Which car 
should I buy?" The answer depends on your 
needs for your computer system. This chapter 
will explain what various peripherals do and 
how much they cost. With this information, you 
will be better equipped to decide which periph- 
erals are suited to your needs. 



157 



COMPATIBILITY 

If you purchase your peripherals from Texas In- 
struments, you are assured that they will be 
compatible, meaning they will work with your 
system. Many peripherals for your TI-99/4A are 
available from the manufacturer and can be 
found in most stores that carry the TI-99/4A 
computer system. A second source of periph- 
erals is the independent companies that provide 
computer accessories. These companies are not 
associated with Texas Instruments, but they do 
manufacture peripherals and software for the Tl 
computer systems. 

When buying from an independent company, 
the company's assurances are often the only 
guarantee offered that the product is truly com- 
patible with your system. This can be a problem. 
On the other hand, the primary advantage of 
dealing with independent companies is price. 
You can often find significant savings on 
accessories from independent companies. 

There is no right or wrong choice to make when 
deciding whether to buy from the manufacturer 
or an independent firm. You must consider the 
cost of the peripheral, the stability of the com- 
pany that produces it, and whether you feel that 
you will be satisfied with the product. 



158 



Texas Instruments Program Recorder 



CASSETTE RECORDER 

A cassette recorder provides the ability to save 
programs and information contained in the com- 
puter by recording them on a cassette tape. You 
also need a cassette recorder to load programs 
from cassette tape into the computer. If you plan 
to use your computer only for entertainment 
and education, you may not need a cassette 
recorder. The TI-99/4A can use the plug-in car- 
tridges containing software programs, and pro- 
grams available in that format may meet your 
needs — particularly for games and for learning 
exercises in many educational subjects. If you 
want to learn to program your computer, you 
will probably also want to use a cassette record- 
er (or a disk drive, but more about that in a 
moment). 



159 



Many models of computers require you to buy a 
specific cassette recorder, but the TI-99/4A is de- 
signed to operate with many different cassette 
recorders. If you already own a cassette record- 
er, it may work with your computer. The record- 
er must have three types of connections: auxil- 
iary, remote, and microphone. These connections 
are normally on the side or front of the recorder. 

You may discover that your recorder will not 
operate when the PLAY button is depressed and 
you give the command OLD CS 1 to load a cas- 
sette program. If your cassette recorder shows 
these symptoms, you probably own a recorder 
that uses a different method of switching the 
cassette motor on and off than is used by the Tl- 
99/4A. You can fix this with a low-cost adapter 
that allows many cassette recorders to operate 
with the TI-99/4As method of recorder control. 
Rather than using an adapter, however, you 
could disconnect the plug that is inserted into 
the jack of your tape recorder. If you do this, the 
recorder will not be under control of the com- 
puter, and you will have to start and stop the 
recorder manually when loading or saving 
programs. 

If you do not have a cassette recorder, you will 
find that to purchase one will cost from S25 to 
$80, so it will pay to compare models when con- 
sidering a cassette recorder for your TI-99/4A. 
Texas Instruments provides a list of cassette 
recorders from numerous manufacturers that 
will operate with the TI-99/4A. 



160 



The Tl Cassette Program Recorder, a portable 
recorder that is designed to accompany the Tl- 
99/4A, costs about $70. The Tl Cassette Program 
Recorder does offer advantages over many tape 
recorders, and it includes the Cassette Interface 
Cable required for connecting the computer to 
the recorder. If you purchase another brand of 
recorder, you must obtain this cable separately 
A digital tape counter and color-coded input 
jacks for ease of setup are features of this record- 
er. And the proper settings of the volume and 
tone controls necessary for saving programs on 
tape are clearly marked — which helps eliminate 
the trial-and-error procedure often required 
when you are using a cassette recorder with 
your computer for the first time. 

One good alternate choice of recorder is the 
General Electric Computer Program Data 
Recorder (for about $50). Designed for use with 
many popular home computers, the GE Data Re- 
corder features a built-in condenser microphone, 
automatic control of recording level, and a digi- 
tal counter that allows simple indexing of various 
programs stored on a cassette. 



161 



Texas Instruments Disk Memory System 
DISK DRIVES 

A disk drive can replace a cassette recorder for 
storing programs and information. By adding a 
disk drive to your system, you gain considerably 
higher performance at a moderate increase in 
cost. 

The first difference that you will notice when us- 
ing a disk drive will be speed: a cassette recorder 
takes from one to five minutes to load software, 
and a disk drive can do it in seconds. A disk drive 
operates efficiently to find infomation, too. It 
stores information using a technique known as 
"random access" — rapidly scanning the surface 
of the magnetic "floppy" disk and quickly locat- 
ing the required information. A cassette record- 
er, by contrast, provides information to the com- 



162 



puter in serial form: the information is recorded 
on the tape as a row of data. If you have a list of 
names and addresses stored on a cassette and 
you want to recall the last name on the tape, the 
computer has to read all of the names on the 
tape until it finds the last one. This can be very 
time-consuming. 

Much of the software for advanced uses, such as 
business applications, is only available on floppy 
disks. The ability to access information in this 
manner allows your computer to create exten- . 
sive file^ the computer uses the disk drive as an 
extension of the computer's memory. 

Disk drives are also a more economical means of 
storage after the initial purchase. A single floppy 
disk will store the equivalent of six cassette 
tapes and is just slightly more expensive than a 
quality cassette tape. Each single-sided 5 Winch 
floppy disk will store approximately 90,000 
characters of information, or roughlyJOO BASIC 
programs that are fifty lines in length. 

Do you need a disk drive? Consider your ap- 
plications. The fast access to information stored 
on the floppy disk makes a disk drive a near- 
must for any computer system used in small 
business applications. If you plan to learn pro- 
gramming, you may need the additional pro- 
gramming commands that are available when 
using a disk drive. 



163 



You can expect to pay from S400 to $650 if you 
decide to add a disk drive to your TI-99/4A com- 
puter system. The Texas Instruments Disk Mem- 
ory System and disk drive cost about $400. A 
disk controller card and software (in the form of 
a disk command cartridge) can be purchased 
separately for about $250. The disk command 
cartridge enables storage of your programs and 
information on S'A-inch floppy disks. The disk 
controller card serves as an interface (adapter) 
between the computer and the disk drive. A 
single disk controller card can control up to 
three disk drives. 

The disk command cartridge, also referred to as 
the Disk Manager, is used to perform house- 
keeping functions for the information that you 
will store on a floppy disk. These functions will 
include naming disks, copying disks, and delet- 
ing files or programs. The use of a software car- 
tridge containing the disk manager software 
allows more space on the floppy disk for actual 
program storage. 

Disk drives can be placed on a smooth surface 
near your computer, or one disk drive can be 
installed in the Tl Peripheral Expansion System (a 
convenient, attractive housing which costs 
about $250). 



164 



Texas Instruments Joysticks 

JOYSTICKS 

To play most games on your computer, you need 
a set of hand controllers, more commonly 
known as joysticks. Many games can be oper- 
ated from the keyboard of your computer, but 
the use of joysticks allows greater control of the 
games with less effort. Tl BASIC also possesses 
commands for tracking the action of the joy- 
sticks; this feature allows you to use the joysticks 
with programs that you may create. 



165 



WICO Joysticks 

Each joystick allows movement in multiple direc- 
tions by means of a tracking handle; a "fire" but- 
ton, used to fire weapons, is included. Tl Joy- 
sticks cost about $35 per pair. If you prefer cus- 
tom joysticks, an alternate choice is the WICO 
Joystick which requires a Tl adapter (sold sepa- 
rately for about $13). The WICO Joystick features 
an oversized bat handle, a palm-sized controller 
base, and two weapons-firing buttons (one is 
mounted at the top of the bat handle). WICO 
Joysticks are not inexpensive (about $30 each); 
however, if you are an avid game enthusiast, 
you may prefer their design. 



166 



Texas Instruments Color Monitor 

MONITORS 

Your system's primary means of communicating 
with you is through its display, so you may want 
to consider buying a monitor The use of a TV set 
(if you have one to begin with ) is generally a 
less expensive option. But due to the limitations 
of television broadcasting, a TV set will not pro- 
duce images and characters that are as sharp 
and clear as those produced by a monitor. 
Whether you decide to use a TV set or a monitor, 
the display should be color if possible. One of 
the primary strengths of the TI-99/4A is its ability 
to display multiple foreground and background 
colors. These colors are used extensively with 
programs written for the TI-99/4A, and the re- 
sultant visual effects are at their best when dis- 
played on a color monitor or color television set. 



167 



Commodore Video Monitor Model 1 701 

The 10-inch Texas Instruments Color Monitor 
(about S400) provides excellent color resolution, 
using an image density of 192 by 256 dots of 
light on the screen. A built-in speaker provides 
sound with adjustable volume control. A re- 
cessed panel hides additional monitor controls 
for contrast and brightness. 

The CBM-1701 Color Monitor from Commodore 
Business Machines (about $300) is a good alter- 
nate choice. Designed for use with home com- 
puters, the Commodore Color Monitor accepts a 
standard composite video signal and audio in- 
put, which makes it compatible with your TI-99/ 
4A. The screen size is 13 inches (diagonally), and 
special circuitry has been included in the moni- 
tor to enhance picture resolution. 



168 




Texas Instruments Impact Printer 
PRINTERS 



When you need a printed record of information 
from your computer, there are two ways to fill 
that need. One way is to use a pencil and paper. 
While this method involves a minimal invest- 
ment, it also grows tiresome quickly. The effi- 
cient method is to use a printer. 

Printers can easily be worth the expense if you 
have sufficient uses for a printer. If you use your 
computer in home financial management, the 
printer can provide storage copies of all transac- 
tions. Most business uses of a personal computer 
require the use of a printer. Mailing lists and the 
typing of forms, letters, and invoices can be 
greatly simplified with your computer and a 
printer. 



169 



Prices of printers vary greatly, as the type of 
printer varies. There are three general types of 
printers that can be used with your TI-99/4A: 
thermal printers, dot-matrix printers, and daisy 
wheel (or letter-quality) printers. Dot-matrix 
printers are the most popular, due to their 
relatively low cost and high reliability In a 
dot-matrix printer, a print head that contains tiny 
hammers moves horizontally across the paper, 
striking the paper through an inked ribbon. 
Thermal printers use treated paper and a heat 
process to "burn" an image onto the paper. 
Daisy-wheel printers use a printwheel with 
letters on the end of tiny spokes (rather like the 
striking surfaces in a typewriter). These spokes 
are moved by a small hammer and strike the 
paper through an inked ribbon, producing the 
character on the paper. Daisy-wheel printers are 
often used for word processing — to print impor- 
tant letters and reports. Thermal printers are 
least expensive, costing from $100 to $400. Dot- 
matrix printers fall into the intermediate price 
range, with prices from $250 to $1,000, depend- 
ing on the quality and features offered. Daisy- 
wheel printers are the most expensive, starting 
around $500 and easily costing $2,000 or more. 
The Tl Impact Printer (about $750) is a dot- 
matrix printer with excellent quality and known 
reliability. This printer prints characters at a 
speed of 80 cps and can print text or graphics, 
under the control of the computer's software. If 
you decide to use the Texas Instruments Impact 
Printer, you will need a cable and the RS-232 
Printer Interface available from Tl. 



170 



Connecting Other Manufacturer's 
Printers to Your TI-99/4A 

A complete computer system is a combination of 
pieces of hardware, and software programs to 
control the hardware's operation. Getting the 
hardware and the software to match can be 
troublesome, particularly in the case of printers. 
Like^most home computer manufacturers, Texas 
Instruments sells printers for its products. But a 
wider variety of printers is available from other 
vendors, and these printers can often be pur- 
chased at a lower cost. 

You can find many of these printers at computer 
stores. You can go as far as to purchase one, cart 
it home, and connect it to your computer, 
expecting that the printer will operate with no 
problems. If it does, consider yourself fortunate; 
you have achieved a perfect match due to sheer 
luck. 

If you choose to use a printer made by an inde- 
pendent company, you will need to purchase 
the RS-232 Interface Card or the RS-232 Inter- 
face Adapter (both priced at about $175; the 
card inserts in the Tl Peripheral Expansion Sys- 
tem, and the adapter plugs into the Expansion 
Connector on the console). 



171 



A printer comes equipped with one of two kinds 
of interface connections: serial or parallel. You 
cannot use a printer with a parallel interface 
connector with your TI-99/4A. The RS-232 Pe- 
ripheral Interface accessories use a type of prin- 
ter interface known in the computer world as a 
serial interface. Buy a printer only if it has a 
serial interface. 

Printers will operate at a variety of speeds (called 
baud rates), and the manufacturers provide 
switches on the printer so that you can set the 
printer at a certain baud rate. Once you have 
done this, you have completed just half of the 
job. The RS-232 Peripheral Interface Card or Pe- 
ripheral Interface Adapter for the TI-99/4A must 
also be set at a speed that will match that of the 
printer. If you're unsure about selecting the 
proper printer, get help — either from the per- 
sonnel at the store where you purchased the 
computer, or from instructions, where available, 
that tell you how to set the switches that are 
used by the printer. Doing so will help put your 
computer and printer on "speaking terms." 



172 




Texas Instruments Expansion System 



MEMORY EXPANSION 

Memory expansion is another option that is 
available for your computer. Before purchasing 
additional memory however, you should con- 
sider your needs to determine if the memory is 
actually needed. Unlike many other computers 
in its price class, the TI-99/4A comes equipped 
with 16K of memory The 16K (about 16,000 
characters) of available memory is enough for 
most home and educational uses. 



173 



If you are programming in BASIC you need 2K 
to 8K of memory for the average simple home fi- 
nance program. A program to perform practice 
exercises in addition or subtraction may use from 
4Kto10K. 

If you use cartridge software, each cartridge 
contains an additional 30K of memory that is 
used by the cartridge program. While you can- 
not access the memory in a cartridge from a 
BASIC program, this memory is used by the car- 
tridge software to perform various functions. 
Much of the available software for the TI-99/4A 
does not require the use of any additional mem- 
ory. So, for most applications, you should not 
need additional memory in your computer. 

Some business applications and advanced 
programming languages do require additional 
memory. For those applications, you need a 
memory expansion card The Tl Memory Expan- 
sion Card (about $300) plugs into the Tl Periph- 
eral Expansion System and adds 32K (about 
32,000 characters) of memory to the computer. 



174 



SPEECH SYNTHESIZER 

Your TI-99/4A is also capable of reproducing 
speech. Few other computers offer this capabil- 
ity. The Tl Speech Synthesizer (about $100) can 
be used with many software packages that 
are designed to offer speech, and it can also be 
programmed to create speech using BASIC 
commands. Milton Bradley also makes a speech 
synthesizer for the TI-99/4A to be used with Mil- 
ton Bradley software only. The Tl Speech Syn- 
thesizer contains an electronic vocabulary of 
over 300 words (you must buy the Speech Edi- 
tor software cartridge to be able to use the 300 
word memory). The Texas Instruments Speech 
Synthesizer can audibly reproduce any 
requested letter or word. The Speech Synthesizer 
does not require the use of the Peripheral Expan- 
sion System, as the synthesizer is designed to 
connect directly to the side of the computer. 



175 



TELEPHONE MODEM 

A final option that you may wish to consider is 
the Tl Telephone Coupler (about $200). A tele- 
phone modem allows your computer to com- 
municate with other computers using ordinary 
telephone lines. A standard telephone headset 
attaches to two rubber cups that are a part of 
the Tl Telephone Coupler, and you then dial the 
number of the computer that you wish to com- 
municate with. With the use of the Tl Telephone 
Coupler, you can access public information net- 
works, such as The Source, CompuServe, Dow 
Jones, and TEXNET. To use the Tl Telephone 
Coupler, you must have an RS-232 Interface 
Card or Adapter on your computer. 

One of the better alternate values for your mod- 
em dollar can be found in the Signalman Mark III 
modem (about $140) from Anchor Automation. 
The battery-powered Signalman Mark III is a 
direct-connect modem that can be used with 
your TI-99/4A. It connects to the telephone with 
the standard four-wire modular telephone jack 
(found in most homes today). 

Your computer's peripherals are its eyes and ears 
to the world. The flexibility offered by your pe- 
ripherals will greatly increase the enjoyment and 
usefulness you receive from your computer 
system. 



176 



CHAPTER 5 

SOFTWARE 



Regardless of how powerful your computer sys- 
tem may be, you will find that software is the 
key to your gaining the greatest satisfaction 
from your system. Every computer, from the 
least expensive home computers to the large 
mainframe computers used by major corpora- 
tions, must have a set of instructions to tell it 
what to do. 

There are two ways for you to give these in- 
structions to your TI-99/4A: you can buy soft- 
ware packages, or you can write your own 
programs in Tl BASIC (thus creating your own 
software). Pre-packaged software that you can 
buy contains all of the steps your computer must 
follow to perform a task — whether the task is 
the planning of your family budget or communi- 
cating with another computer hundreds of miles 
away. The cost of such software can range from 
a small investment (about S10 to $40 for many 
home applications) to a large investment (hun- 
dreds of dollars for some business applications). 



177 



When computers similar to your TI-99/4A first 
appeared on the consumer market, the amount 
of pre-packaged software was limited, and you 
were often forced to learn programming so that 
you could create your own software. Fortunate- 
ly this situation has changed, and a wide array 
of software is available for your computer. You 
can still write your own software if you want to, 
but you don't have to. 

The TI-99/4A can use cassette, cartridge, or disk 
software. All three of these software formats 
have advantages and disadvantages. What for- 
mats) you decide to use will depend on what 
you want to use the computer for and how 
much money you want to spend. 



178 



CARTRIDGE SOFTWARE 

Cartridges are the easiest type of software to 
use. They can be used by young children, and 
they offer convenience and speed of program 
loading as primary benefits. For this reason, you 
will find that most educational software for the 
TI-99/4A comes in cartridges. 

Cartridge software often provides detailed color 
graphics and fast action (with movements that 
are often faster than you will see with cassette 
or disk-based software). The reason for the fast 
graphics and sound is that cartridge software 
uses the computer's native programming lan- 
guage, known as machine language. Game 
programmers use machine language to create 
fast-action arcade games. In contrast, many cas- 
sette and disk programs use Tl BASIC or Tl Logo, 
programming languages that are considerably 
easier to use, but not as fast in operation. 

The primary disadvantage of cartridge software 
is the inability of cartridges to store any informa- 
tion from the computer. A lesser disadvantage is 
that, in some cases, cartridge software is slightly 
more expensive than comparable software in 
cassette form. 



179 



CASSETTE SOFTWARE 

Cassette software for your TI-99/4A is recorded 
on standard audio cassettes. Cassette software 
is loaded into the computer by means of a cas- 
sette recorder that is connected to the computer. 

Cassette software is popular because it is inex- 
pensive. You do have to have a cassette recorder, 
but the low cost of the individual cassettes is 
attractive. 

You can buy cassettes with programs written on 
them, or you can buy blank cassettes. With a 
cassette, unlike a cartridge, you have the option 
of writing your own programs and saving them. 
Creating software in this manner is inexpensive 
(and fun!). Cassettes do not, however, provide 
the flexibility in programming offered by the use 
of a disk drive. 

The primary disadvantage of cassette software 
is the time required to load programs into your 
computer. The exact length of time required will 
vary (from one to five minutes or more), depend- 
ing on the length of the program. 

Despite the possible limitations, many owners of 
TI-99/4A computer systems use cassettes as a 
viable means of storing programs and informa- 
tion. This method is low in cost, reliable, and sim- 
ple to use. 



180 



DISK SOFTWARE 

Floppy disks for your TI-99/4A are S'/nnch, flat, 
flexible magnetic disks with protective jackets. 
They look something like 45 RPM records. You 
can buy disks with programs written on them, or 
you can buy blank disks. The disks themselves, 
and even some of the disk software, are not too 
expensive, but to use them you have to have a 
disk drive — and that is not cheap. 

There are notable advantages to using disk soft- 
ware, however. The same program that takes 
five minutes to load into the computer from a 
cassette will be loaded in seconds when using 
a disk drive. In addition to the advantage of 
speed, disk drives also provide flexibifity in the 
way that the computer uses information; be- 
cause the disk drive uses a recording method 
known as random access, it is possible for the 
disk drive to locate a given bit of information 
(data) in a short time. By comparison, if that 
same bit of information is recorded at the end of 
a cassette, your computer must load the con- 
tents of the entire cassette into memory before 
the needed information is found. 

The initial cost of the disk drive is the primary 
disadvantage of disk software, but if you pur- 
chase a disk drive, you will find a variety of 
advanced software, such as many business ap- 
plications, available on floppy disks. 



181 



CARE OF SOFTWARE 

One of the most common causes of problems 
when using your computer is the mishandling of 
software. While some mistreatments are obvious 
(such as the toddler getting at your floppy disk), 
there are more subtle ways of mishandling soft- 
ware which can cause problems. There are defi- 
nite "do's and don'ts" regarding handling of 
software. 

MAGNETIC FIELDS: Strong sources of magnet- 
ism can erase your cassettes or floppy disks. 
Keep your software away from electric motors, 
magnetized paper clip hangers, and the like 
(including your TV). 

SHOCK AND VIBRATION: If you're using cas- 
sette software, shock or vibration can cause the 
cassette spools inside the container to shift, and 
jamming of the tape may occur. Rewinding the 
tape will usually solve the problem. 

EXTREME TEMPERATURES: Cassettes and disks 
can warp or stretch if they are stored in hot en- 
vironments. Keep your software away from 
direct sunlight. 



182 



AIRPORT METAL DETECTORS: Contrary to pop- 
ular belief, most airport metal detectors will not 
harm computer software, because most metal 
detectors use X-rays, which will not affect mag- 
netic disks or tapes. To be on the safe side, 
however, ask the airport security attendant to 
hand-inspect any software you want to carry 
onto the plane. 

LABELING SOFTWARE: Whting on cassettes 
is not a problem, but writing on a floppy disk 
jacket can be disastrous if you press too hard. 
Never use a ball-point pen to write on a label 
that's attached to the jacket of a floppy disk. In- 
stead, use a felt-tipped marker and press lightly. 
A ball-point pen can leave a permanent bend in 
the surface of the disk, and the computer will 
not be able to read the information on the disk's 
surface. 

LOSS: If you obtain a large quantity of software, 
you may find your software collection becoming 
disorganized. To prevent this, you can buy a 
holder for your cartridges, cassettes, or disks. 
These holders will protect your software when it 
is not in use. Texas Instruments offers a storage 
cabinet (about $15) that will hold 12 cartridges 
or cassettes in two sliding drawers. And most 
computer or software stores sell binders or 
boxes for the storage of floppy disks. 



183 



SOURCES OF SOFTWARE 

Don't overlook the various sources of software 
for your computer. Dealers that carry the Texas 
Instruments line are a primary source of soft- 
ware, but other sources exist as well. Indepen- 
dent companies produce software for your 
computer in the fields of entertainment educa- 
tion, home, and business. Many of the indepen- 
dent software makers advertise in computer 
magazines. Users' groups should also be consid- 
ered as a valuable source of software. Users' 
groups are groups of people who share a par- 
ticular interest in computers. Many cities have 
one or more TI-99/4A users' groups that meet 
on a regular basis to share ideas, solve problems, 
and offer suggestions. Users' groups also often 
exchange software written by members of the 
group. (For more information concerning users' 
groups, see Chapter 6, "Your Computer's Net- 
work.") 

If you prefer to create your own programs, 
books are available with sample programs for 
the TI-99/4A. These programs may be typed into 
the computerand saved on cassette tape or 
floppy disk. Should you decide to use this source 
of software, make sure that the book that you 
purchase is written specifically for the Texas 
Instruments TI-99/4A. There are a number of 
books on the market that contain BASIC pro- 
grams written to run on most computers. But 
each computer's version of the BASIC pro- 
gramming language has subtle differences. 
These differences can cause incorrect operation 



184 



of the program that you enter into the computer. 
You will avoid this problem by purchasing a book 
containing programs that have been tested on 
theTI-99/4A. 

When you buy blank cassettes to type programs 
of your own, try to get short ones (15 or 20 
minutes) because they are less expensive and 
generally more durable. Whenever you buy pre- 
packaged software, make sure that you get a 
factory-sealed package. Also be certain that you 
can return a defective or damaged cartridge, 
cassette, or disk. 

Most pre-packaged software is copyrighted. 
When you buy programs of this type, you can- 
not legally copy them and give or sell them to 
anyone else. Programs which are published in 
books and magazines, however, are public do- 
main software. Software written by your friends 
may also be in the public domain — that is, it is 
not copyrighted and is available for use by the 
general public, usually without a fee. Some com- 
panies even sell public domain software; they 
type the program into a computer, save it on a 
cassette or disk, make copies, and sell them. Fees 
for public domain software are generally very 
low — perhaps S5 per program to cover the 
costs of making the copy. 



185 



SOFTWARE COSTS 

The cost of software for your computer will vary 
greatly depending on the specific software. 
Most software intended for entertainment edu- 
cational, and home use will be priced in the $10 
to $50 range. Software for business applications 
tends to be considerably higher in cost, ranging 
from $50 to $200 or more. 

Cassette software for your computer is generally 
priced in the $10 to $40 range, while cartridge 
software is often priced in the $20 to $50 range. 
There are a few exceptions to such costs: the 
Microsoft Multiplan electronic spreadsheet car- 
tridge and the Tl Extended BASIC cartridge both 
cost about $100. Software that is contained on 
floppy disk will cost from $20 to over $200, de- 
pending on the complexity of the program. 

COMPATIBILITY 

Compatibility in the personal computer world 
refers to the ability (or inability) to use one type 
of product on a particular computer system. Be- 
fore purchasing software for your computer, 
make sure that the software is compatible with 
your system. 

Software that is made by the computer manu- 
facturer tends to be compatible with most, but 
not all, of the manufacturer's computers. In some 
cases, your TI-99/4A must be equipped with 
additional memory or other options to use a par- 
ticular program. Many powerful business soft- 
ware packages are available only on floppy disk. 



186 



Your system must have a disk drive to be able to 
use these software packages. 

To determine if the software is compatible with 
your system, always read the packaging or in- 
structions that accompany the software before 
you purchase it 

USING SOFTWARE 

All you have to do to use a cartridge is plug it 
into the cartridge slot on the computer console 
and turn the computer on. To use a cassette, fol- 
low STEPS 1-7 under the section "MAKING 
CASSETTE BACKUP COPIES" to load the pro- 
gram into the computer, and then follow the 
directions as they appear on your screen. To 
use a disk, follow STEPS 1-4 under the section 
"MAKING DISK BACKUP COPIES" to load the 
program, and then follow the directions as they 
appear on your screen. 

Pre-packaged software always comes with 
printed instructions for its users. These instruc- 
tions are called documentation. Always read the 
documentation very carefully when you are us- 
ing a program with which you are unfamiliar. If 
you can, read the documentation before you 
buy the software; this will help you make sure 
that the program you are buying actually does 
what you want it to do. 



187 



PROTECTION OF SOFTWARE 

Before you use any pre-packaged cassette or 
disk, make a backup copy. Cassettes and disks 
do wear out. After much use, they develop 
errors. Backup copies extend the useful life of 
your programs by letting you save the master 
(original) cassette or disk; the master should be 
used only to make new error- free program 
copies. Use the backup copy whenever you run 
a program. That way in case anything happens 
(like an electrical surge or lapse) your original 
program is safe. 

Some software manufacturers have written pro- 
grams which are difficult or impossible to copy. 
Before you buy a program, ask your dealer if it 
can be copied. If you have another option, don't 
buy this kind of software. If you already own 
some, or if you really need that particular pack- 
age, check with your dealer or the manufacturer. 
Sometimes, with proof of purchase, you can get 
backup copies for a nominal fee. 



188 



MAKING CASSETTE BACKUP COPIES 

To make a backup copy, you will have to load 
the program into the computer from the original 
cassette tape. Then you will unload (or SAVE) 
the program onto a new, blank cassette tape. 
Here's how you load the program into the 
computer. 

STEP1 

Turn on the computer console and the TV set 
Plug the cassette recorder into both the wall and 
the computer (see the instructions for setting up 
a cassette recorder in Chapter 2). 

STEP 2 

Insert the cassette tape containing the program 
you want to use into the recorder face up. Close 
the cover over the tape. 

STEP 3 

Type 

OLD CS1 

and press the ENTER key. 
STEP 4 

On the screen, you will see the following 
message: 

*REWIND CASSETTE TAPE CS1 
THEN PRESS ENTER 



189 



Push the REWIND button on your cassette 
recorder. When the tape stops rewinding/press 
the ENTER key on your computer console. This 
brings a new command onto the screen. 

STEP 5 

The new command will be the following: 

*PRESS CASSETTE PLAY CS1 
THEN PRESS ENTER 

Push the PLAY button on your cassette recorder. 
Then press the ENTER key on your computer 
console. 

STEP 6 

Now relax. The screen message will say 
*READING 

This message may stay on the screen for as long 
as five minutes, depending on the size of the 
program you are loading. When the message 
changes to 

*DATA OK 

it's finished loading. 



190 



STEP 7 

The message 

*PRESS CASSETTE STOP CS1 
THEN PRESS ENTER 

appears on the screen. So push the STOP button 
on your cassette recorder and then the ENTER 
key on the computer console. 

Bravol You have loaded a program Into your 
computer. 

If, Instead of the *DATA OK message, you got a 
message which said 

*ERROR = NO DATA FOUND 
PRESS R TO READ 
PRESS E TO EXIT 

or 

*l/0 ERROR 56 
something Is amiss. 

If no data was found, you may have put the 
tape in upsidedown or you may have used a 
blank tape by mistake. Examine the tape. Then 
replace it correctly into the recorder, close the 
lid, push the PLAY button on the cassette 
recorder, and press the R key on the computer 
console. Now go back to STEP 6. 



191 



If *l/0 ERROR 56 appeared, check the cable 
connecting the cassette recorder to the com- 
puter console. Then go back to STEP 3. 

The program Is now loaded Into your com- 
puter's memory. You will use these same seven 
steps to load any program from your cassette 
recorder into your computer, whether you are 
making a copy of the program or running it. 

To complete the making of the backup copy 
follow these eleven steps to SAVE (unload) 
your program onto a cassette tape. 

STEP1 

Remove the tape which you have just loaded 
into the computer from the cassette recorder. 

STEP 2 

Insert a new, blank tape into the recorder and 
close the cover over the tape. 

STEP 3 

Type 

SAVECSl 

and press the ENTER key. 



192 



STEP 4 

On the screen, you will see the following 
message: 

*REWIND CASSETTE TAPE CS1 
THEN PRESS ENTER 

Push the REWIND button on your cassette 
recorder. When the tape stops rewinding, press 
the ENTER key on your computer console. This 
brings a new command onto the screen. 

STEP 5 

The new command will be the following: 

*PRESS CASSETTE RECORD CS1 
THEN PRESS ENTER 

Push the RECORD button on your cassette 
recorder. Then press the ENTER key on your 
computer console. 

STEP 6 

Now relax againl The screen message will say 
♦RECORDING 

This message may stay on the screen for as 
long as five minutes. When the program has 
been SAVED, another message will appear 
on the screen: 

*PRESS CASSETTE STOP CS1 
THEN PRESS ENTER 



193 



Push the STOP button on your cassette recorder. 
Then press the ENTER key on the computer 
console. 

STEP 7 

The message 

*CHECK TAPE (Y OR N)? 

appears on the screen. Press the Y key on the 
computer console. (If you were to press the N 
key Instead, the computer would erase its 
memory and return you to Tl BASIC on the 
screen. Always check to be sure that the tape 
has recorded the program correctly from the 
computer memory.) 

STEP 8 

More instructions appear on the screen: 

♦REWIND CASSETTE TAPE CS1 
THEN PRESS ENTER 

Push the REWIND button on your cassette 
recorder. When the tape stops rewinding, press 
the ENTER key on your computer console. This 
brings a new command onto the screen. 



194 



STEP 9 

The new command will be the following: 

*PRESS CASSETTE PLAY CS1 
THEN PRESS ENTER 

Push the PLAY button on your cassette recorder. 
Then press the ENTER key on your computer 
console. 

STEP 10 

Relax one more time. The screen message 
will say 

♦CHECKING 

This message may stay on the screen for as long 
as five minutes. When the message changes to 

*DATA OK 

it's finished checking. 

STEP 11 

The message 

*PRESS CASSETTE STOP CS1 
THEN PRESS ENTER 

appears on the screen. So push the STOP button 
on your cassette recorder and then the ENTER 
key on the computer console. 



195 



If, instead of the *DATA OK message, you got a 
message which said 

*ERROR= NO DATA FOUND 
PRESS R TO RECORD 
PRESS C TO CHECK 
PRESS E TO EXIT 

or 

*ERROR IN DATA DETECTED 
PRESS R TO RECORD 
PRESS C TO CHECK 
PRESS E TO EXIT 

or 

*l/0 ERROR 66 
something is amiss. 

If the *l/0 ERROR 66 message appeared, check 
the cable connecting the cassette recorder to 
the computer console. 



196 



If one of the other error messages appeared, you 
have three choices: 

• Press the C key to CHECK the recording 
again. (Before you do this, however, adjust the 
recorder volume and tone controls to the 
correct levels.) 

or 

• Press the R key to record the program again. 
(Then follow the eleven steps for saving a pro- 
gram onto a cassette tape.) 

or 

• Press the E key to exit the recording process. 
(Then follow the instructions which appear on 
your screen.) 

With some cartridge software, you can SAVE 
(onto the cassette) data which you have gener- 
ated using the cartridge. To SAVE material from 
a cartridge onto a cassette tape, follow steps 1-1 1 
exactly as if you were saving material original- 
ly loaded from a cassette. 



197 



MAKING DISK BACKUP COPIES 

To make a backup copy of a program on a disk 
you will initialize (or format) a blank disk, a pro- 
cedure we will explain in the steps that follow. 
Then you will have to load the program into the 
computer from the original disk and unload the 
program onto the newly initialized disk. Using 
one disk drive, this process takes several passes. 

Here's how you initialize the blank disk: 

STEP1 

Turn on the disk drive system, the TV set, and 
the computer console. 

STEP 2 

Open the little door on the disk drive. Pick up a 
blank disk and hold it with the label facing up 
and the part with the uncovered section of the 
disk facing away from you. Insert the disk into 
the disk drive, and close the little door. 

STEP 3 

Plug the Disk Manager Command Module (the 
cartridge that came with your Tl Disk Memory 
System) into the cartridge slot on the computer 
console. 

STEP 4 

Press any key on the keyboard. 
STEPS 

Press the 3 key, to select the Disk Manager Com- 
mand Module. 



198 



STEP 6 

The following message will appear on your 
screen: 

DISK MANAGER 

1 FILE COMMANDS 

2 DISK COMMANDS 

3 DISK TESTS 

4 SET ALL COMMANDS FOR 
SINGLE DISK PROCESSING 

YOUR CHOICE? 

After the YOUR CHOICE? message on the 
screen, the cursor will flash, alternating with the 
character 1. Press the 2 key (and then press the 
ENTER key). 

STEP 7 

The following message will appear on your 
screen: 

DISK COMMANDS 

1 CATALOG DISK 

2 BACKUP DISK 

3 MODIFY DISK NAME 

4 INITIALIZE NEW DISK 

YOUR CHOICE? 

Again, after the YOUR CHOICE? message, the 
cursor will flash, alternating with the character 1. 
Press the 4 key (and then the ENTER key). 



199 



STEP 8 

The following message will appear on your 
screen: 

INITIALIZE NEW DISK 
MASTER DISK (1-3)? 
DISK NOT INITIALIZED 

Press the I key and the ENTER key since you 
are working with one disk drive. 

STEP 9 

The computer will ask you to name the disk: 

NEW DISKNAME 

So now you want to name the new disk. Any 
name up to ten characters, with no periods or 
spaces in it, will work. You will want to develop 
your own system for naming disks and copies. 
The first copy of your word processing program 
disk, for example* might be named WPC1 (for 
Word Processing Copy 1 ). 

Type your disk name choice now and press the 
ENTER key 



200 



STEP 10 

The computer accepts your program name and 
displays the following message on the screen: 

40 TRACKS (Y/NJ? 

Whether your disk has 35 or 40 tracks will 
depend on what brand of blank disks you 
bought. When you buy blank disks, ask your 
dealer how many tracks they hold. 

If the disk you are using has 40 tracks on it press 
the Y key (and then the ENTER key). If the disk 
you are using has 35 tracks on it, press the N 
key (and then the ENTER key) and the disk will 
be initialized for 35 tracks. 

STEP 11 

The message 

SCREEN IS COMPLETE 

PRESS: PROC'D, REDO, BEGIN, OR BACK 

will appear on your screen. Press the 
FUNCTION-6 key combination (for the 
PROC'D function) and you have finished ini- 
tializing your blank disk. The whole process 
(when you have practiced) takes about a 
minute. 



201 



The message 



INITIALIZING NEW DISK 
WORKING .... PLEASE WAIT 

appeared on your screen briefly and was 
replaced by the message 

DSK1 - DISKNAME = diskname 
AVAILABLE = 358 USED = 

This tells you that the disk is indeed blank, but 
that it has been initialized and named. 

STEP 12 

Open the disk drive door and remove the 
initialized disk. 

To actually make the backup copy follow 
these steps: 

STEP1 

Turn the computer off and then back on. This is 
called rebooting the system. (Turning it on in the 
first place is called booting the system.) 

STEP 2 

Press any key on the keyboard. 
STEP 3 

Press the 3 key to select the Disk Manager 
Command Module. 



202 



STEP 4 

The following message will appear on your 
screen: 

DISK MANAGER 

1 FILE COMMANDS 

2 DISK COMMANDS 

3 DISK TESTS 

4 SET ALL COMMANDS FOR 
SINGLE DISK PROCESSING 

YOUR CHOICE? 

After the YOUR CHOICE? message on the 
screen, the cursor will flash, alternating with the 
character I. Press the 2 key (and then the ENTER 
key). 

STEPS 

The following message will appear on your 
screen: 

DISK COMMANDS 

1 CATALOG DISK 

2 BACKUP DISK 

3 MODIFY DISK NAME 

4 INITIALIZE NEW DISK 

YOUR CHOICE? 

Again, after the YOUR CHOICE? message, the 
cursor will flash, alternating with the character 1. 
Press the 2 key (and then the ENTER key). 



203 



STEP 6 

The following message will appear on your 
screen: 

SELECTIVE (Y/N)? 

Since you want to copy the entire contents of 
the original disk, press the N key (and then the 
ENTER key). 

STEP 7 

A new message will ask you which drive you 
have the master disk in: 

MASTER DISK (1-3)? 

Since you are using one disk drive, press the I 
key (and then the ENTER key). 

STEP 8 

The message 

DISKNAME 

will appear on the screen. Type the name of the 
original (master) disk, and then press ENTER. 



204 



STEP 9 

Now the computer will ask you in which drive 
you have the disk you want the copy made on: 

COPY DISK (1-3 J? 

Again, since you are using one disk drive, press 
the 1 key (and then the ENTER key). 

STEP 10 

Now the computer has a command for you: 

LOAD MASTER DISK 

Respond to this command by putting the 
original disk into the drive. Then press the 
FUNCTION -6 key combination (to tell the 
computer to PROCEED). 

STEP 11 

You will hear some whirring of the disk drive, 
and the red light on the drive will be lit Then the 
light will go out and the message 

LOAD COPY DISK 

will appear on your screen. 

Take the master disk out of the drive and insert 
the copy disk (the one you just initialized). Then 
press the FUNCTION -6 key combination (to 
tell the computer to PROCEED). 



205 



Repeat steps 10 and 1 1 several times to copy all 
of the Information from the original to the copy 
disk. The screen will display the next step while 
the disks are whirring; do not do it until the red 
light on the drive goes out 

STEP 12 

When you finish, the message 

COMMAND COMPLETE 
PRESS PROC'D, REDO, OR QUIT 

appears on the screen. If you want to work on 
the program, press the FUNCTION -6 key 
combination to PROCEED. If you want to try 
copying it again, press the FUNCTION -8 key 
combination to REDO. If you want to stop, press 
the FUNCTION and=/+ key combination to 
QUIT. 



206 



CATEGORIES OF SOFTWARE 

Because the TI-99/4A is designed to be a home 
computer, most of the software for it is aimed 
at the home user. Software can generally be 
categorized into about four groups, based on its 
uses: games/entertainment education, home/ 
business management and computer lan- 
guages. 

Entertainment and educational software for 
your computer exists primarily in cartridge form, 
although many educational programs are avail- 
able on floppy disk. Home finance management 
is also a popular application and is available in 
various forms. Business applications are possible 
using your TI-99/4A; limited word processing, 
financial accounting, investment tracking, and 
financial projections can be performed with 
appropriate software, which is available primari- 
ly on disk. 

RECOMMENDED 
GAMES/ENTERTAINMENT 
SOFTWARE PROGRAMS 

The Attack is an arcade-style game with fast 
color graphics. The Attack places you at the 
helm of a spaceship, and you must destroy alien 
ships by firing missiles while avoiding collisions 
at the same time. This game is recommended en- 
tertainment for all ages. 
Format: Cartridge 
Options needed: Joysticks 
Supplier: Texas Instruments 



207 



Car Wars is an arcade game of skill. In Car Wars, 
you must play against the computer. You are 
forced to maneuver your car around a racetrack 
while avoiding obstacles in the road. Car Wars 
can be played at various skill levels and can 
be played with or without joysticks. 
Format: Cartridge 
Options needed: None 
Supplier: Texas Instruments 

Tl Invaders is a single-player game that pits you 
against waves of alien invaders, rather like the 
action in the popular Space Invaders arcade clas- 
sic. You have a supply of missiles that you must 
use to defend your base against the attacking 
forces. 77 Invaders can be played with or with- 
out joysticks. 
Format: Cartridge 
Options needed: None 
Supplier: Texas Instruments 

Strike Force 99 is a space game in which you 
must pilot your starship along a narrow channel 
of the Cyrolian death ship to destroy it before 
it has the opportunity to destroy your home 
planet. You must simultaneously deal with 
attacking enemy fighters during your mission. 
The program features impressive three- 
dimensional graphics. 
Format: Cassette 

Options needed: Joysticks, Tl Extended BASIC, 
Cassette recorder 

Supplier: Moonbeam Software, 2 Bridge St., 
Northampton, MA 01060 



208 



ZAXXON is one of the most popular arcade 
games developed to date which is available for 
your TI-99/4A ZAXXON creates a three-dimen- 
sional playfield in which you must pilot your 
fighter — climbing, diving, and firing at enemy 
ground targets — as the enemy fights back with 
a barrage of missiles and gunfire. The realistic 
control of the fighter and the three-dimensional 
graphics technology behind ZAXXON make this 
game a must 
Format: Cassette or disk 
Options needed: Joysticks, Cassette recorder 
or disk drive 

Supplier: Datasoft, Inc., 9421 Winnetka Ave., 
Chatsworth,CA91311 

Indoor Soccer is playable with one or two play- 
ers. Indoor Soccer simulates a five-person soccer 
game. You control the players and you are able 
to shoot, pass, intercept save, and perform 
tackles. An instant replay of each score can also 
be displayed on the screen. 
Format: Cartridge 
Options needed: Joysticks 
Supplier: Texas Instruments 



209 



HINTS ON BUYING EDUCATIONAL 
SOFTWARE 

If you plan to use your computer as an educa- 
tional tool, you may already have purchased 
educational software aimed at a particular sub- 
ject. But beyond that you may have the same 
questions that many other new computer own- 
ers have about educational software: What is 
available? What can it do? How do you decide 
what kind to buy? 

Most educators agree that educational software 
can aid in the learning process; computers are 
particularly effective in providing remedial help 
aimed at specific subjects. While most software 
packages on the market offer repetitive drill in a 
particular subject other types of software can 
also aid the student who quickly grows bored 
with subjects that he or she has mastered. When 
this type of student is allowed to experiment 
with simulations and learning games on the 
computer, advanced concepts sink in more 
readily. In addition, the cost of the computer and 
software is usually less than the cost of a few 
months of private tutoring. Therefore, there are 
many advantages to purchasing educational 
software for your computer. 



210 



A good educational software package will go 
farther than simply "turning the pages of a 
book" in an electronic fashion. The learning 
objectives should be clear with any software 
package that you're considering. The learner 
should know what the software is intended to 
teach. There should be clear documentation (in- 
structions) for the use of the software. Before 
you buy, ask to see the software in operation 
and look for software that appears to teach (as 
opposed to just presenting drills). The software 
should also provide positive reinforcement if the 
answers are correct and should never be over- 
bearing on negative reinforcement for wrong 
answers. 

The software should be user-friendly, the age 
group for which it is targeted should be able to 
use the program without constant assistance. If 
young children are the users, the information 
that's presented should match the child's read- 
ing level. This may seem like an obvious point, 
but there are software packages on the market 
that ignore this rule. 



211 



RECOMMENDED EDUCATIONAL 
SOFTWARE PROGRAMS 



Early Learning Fun proves that in many cases, 
children aren't too young to begin the learning 
process with the aid of a computer. Designed for 
children ages 3 through 6, Early Learning Fun 
familiarizes young children with numbers, let- 
ters, shapes, and counting and sorting. 
Format: Cartridge 
Options needed: None 
Supplier: Texas Instruments 

Addition/Subtraction 1 and 2, Multiplication 
1, and Division 1 is a series of educational soft- 
ware developed for Texas Instruments by Scott, 
Foresman and Company, a major educational 
publisher. It is a series of quality educational soft- 
ware, structured for various levels of learning. 
Each of these software packages provides exer- 
cises to teach the basic concepts, foltowed by 
practice in the specific area. Addition/ 
Subtraction 1 and 2 are for grades 1 and 2, 
Multiplication 1 is for grades 3 and 4, and 
Division 1 is for grades 3 through 5. 
Format: Cartridge 

Options needed: None, but speech synthesizer 
is recommended 
Supplier: Texas Instruments 



212 



Speak and Spell operates like the popular Tl 
Speak and Spell learning aid. The program 
teaches elementary school children the correct 
pronunciation and spelling of words. The pro- 
gram aids in pronunciation by using the speech 
synthesis capabilities of the TI-99/4A 
Format: Disk 

Options needed: Speech synthesizer 
Supplier: Texas Instruments 

Early Reading also makes use of speech syn- 
thesis capabilities to introduce reading skills to 
preschool and early elementary school children 
at an early age. Color graphics and action fig- 
ures are combined with the use of sound to 
maintain the attention span of younger children. 
Format: Cartridge 

Options needed: Speech synthesizer 
Supplier: Texas Instruments 

PLATO Courseware is a comprehensive series 
of educational software aimed at students in 
grades 3 through 12. The series covers all basic 
skills (reading, grammar, and mathematics) for 
grades 3 through 8, and math, reading, writing, 
grammar, social studies, and science at the high 
school level. PLATO Courseware packages are 
designed for the TI-99/4A owner who wants to 
make a long-term investment in quality educa- 
tional software. But before you can use PLATO 
Courseware, your computer must be equipped 
with a memory expansion card, a disk drive, and 
a PLATO interpreter disk. 
Format: Cartridge and disk combination 



213 



Options needed: Tl Peripheral Expansion Sys- 
tem, memory expansion card, disk drive with 
disk controller card 
Supplier: Control Data 

Key To Spanish is a package which includes 
four software cartridges, four audio cassettes, 
and an instructional manual, all contained in a 
three-ring binder. Key To Spanish concentrates 
on words and phrases commonly found in day- 
to-day Central and South American Spanish. Les- 
sons and word games are programmed into the 
software cartridges. The audio cassettes, under 
computer control, provide positive reinforce- 
ment of the proper pronunciation of Spanish. 
Format: Cartridge, with audio cassettes 
Options needed: Cassette recorder 
Supplier: Texas Instruments 

Speech Editor is a software package that 
allows you to directly use the speech capabilities 
of the Tl speech synthesizer. This option can be 
particularly useful for the visually impaired, as 
it lets you send spoken words, sentences, or 
phrases to the speech synthesizer. The Speech 
Editor package includes about 300 pre- 
programmed words from which you can choose. 
It does not allow you to use words that are not 
already in the program. The words that are to be 
spoken by the speech synthesizer are typed in at 
the keyboard. 
Format: Cartridge 

Options needed: Speech synthesizer 
Supplier: Texas Instruments 



214 



RECOMMENDED HOME/BUSINESS 
MANAGEMENT SOFTWARE PROGRAMS 



Household Budget Management is designed 
to let the average household track a family 
budget and maintain income and expense re- 
cords. The program creates a budget that you 
can maintain on a month-to-month basis, and it 
will display and print (with optional printer) 
tables and charts that reflect your expense pat- 
terns. 

Format: Cartridge 

Options needed: Cassette recorder or disk 
drive 

Supplier: Texas Instruments 

Personal Recordkeeping is a data base man- 
agement (or electronic filing) system for the Tl- 
99/4A It allows you to create a filing system and 
retrieve and update information within the sys- 
tem at any time. You can use it for various home 
or small business tasks, such as inventory rec- 
ords/ medical or dental records, tax or insurance 
information, and address lists. 
Price: About $50 
Format: Cartridge 

Options needed: Cassette recorder or disk drive 
Supplier: Texas Instruments 

Tl Writer is a word processing program de- 
signed for the TI-99/4A Using Tl Writer, you can 
create letters, documents, and forms on your 
screen and then produce error-free text on a 
printer connected to your system. Tl Writer's fea- 



215 



tures include text insertion and text deletion 
from any point within the document automatic 
paragraph indent underlining, block movement 
of text and reformatting of documents. 
Format: Cartridge 

Options needed: Peripheral Expansion System, 
disk drive with disk controller, 32K memory ex- 
pansion card, printer 
Supplier: Texas Instruments 

X Tl-Count Business Series is a series of six 
accounting programs contained on floppy disk. 
The programs include General Ledger, Accounts 
Payable, Accounts Receivable, Payroll, Inventory, 
and Mailing List Information that is entered into 
the General Ledger is automatically updated in 
the Accounts Payable, Accounts Receivable, and 
Payroll files. 
Format: Disk 

Options needed: Extended BASIC Cartridge, 
Peripheral Expansion System, disk drive with 
disk controller, RS-232 interface card, and printer 
(32K memory expansion card and second disk 
drive are recommended but not required) 
Supplier: Texas Instruments 

COMPUTER LANGUAGES 

If you plan to learn advanced programming, you 
will want to consider purchasing additional 
computer programming languages for your sys- 
tem. Computer languages add to the flexibility 
of programming your computer. Each pro- 
gramming language has its strengths, and differ- 
ent languages are designed for specific tasks. 



216 



Tl Extended BASIC is an upgraded version of 
the Tl BASIC that is built into your computer. 
While the standard version of BASIC can be used 
for many programming tasks, the Extended 
BASIC option will allow the use of many addi- 
tional programming functions. Features that are 
added by the use of Extended BASIC include the 
following: 

• Multiple program statements on a single line 

• Immediate execution of IF-THEN statements 

• Use of the RUN command within a program 

• Ability to merge multiple programs 

• Built-in error handling 

• Support of the Tl Peripheral Expansion Unit 

• Support of sprite graphics (moving graphics 
shapes) for detailed animation 

Of all of the features offered by Extended BASIC, 
the feature you are likely to find most helpful in 
programming is the use of multiple statements 
on a single program line. Most personal com- 
puters use a variation of Microsoft BASIC, a lan- 
guage patented by Microsoft Corporation. 
Microsoft BASIC supports multiple statements 
on a single line, so that a command line of a 
BASIC program could look like this: 

10 PRINT "HELLO": PRINT "MY NAME IS": 
PRINT "COMPUTER." 

When you are using normal Tl BASIC, y<?u can- 
not use multiple statements on a single iine. So 
that same program would be written as: 



217 



10 PRINT "HELLO" 

20 PRINT "MY NAME IS" 

30 PRINT "COMPUTER." 

Since many books that list sample BASIC pro- 
grams make use of multiple statements on a 
single line, you may find that extensive rewriting 
of these programs is necessary before you can 
use them with Tl BASIC. You will be able to use 
such programs with less redesign if you use Tl 
Extended BASIC. The use of multiple statements 
on a single line also consumes less of your com- 
puter's memory, allowing the use of longer 
BASIC programs. 
Format: Cartridge 
Options needed: None 
Supplier: Texas Instruments 

Tl Logo brings simplicity in programming to all 
ages. Logo is more than a language; it is also a 
learning environment based on a philosophy of 
education. Logo's underlying design is to create 
a computer-based environment that allows 
learning to occur in a natural manner. Tl Logo is 
an excellent learning resource for young chil- 
dren; it lets children communicate with the 
computer by using a language that is easily 
understood. With commands like TELL TURTLE 
FORWARD, SETCOLOR BLUE, and CARRY 
TRUCK, children can explore the basics behind 
math and science without realizing that they are 
doing so. If you plan to use your computer as a 
learning aid, Tl Logo will prove to be a worth- 
while investment. Many of the nation's 



218 



elementary schools are now using a version of 
Logo in computer literacy programs. 
Format: Cartridge 

Options needed: Memory expansion card 
Supplier: Texas Instruments 

Tl Logo II is an updated and refined version of 
Tl Logo. There are enhanced commands available 
in the programming structure, as well as printer 
capability using the optional RS-232 interface 
card. Tl Logo II also provides on-screen sprites 
(moving graphics shapes) that are larger in size 
than the original sprites, as well as music. 
Format: Cartridge 

Options needed: Peripheral Expansion System, 
memory expansion card 
Supplier: Texas Instruments 

UCSD Pascal is an efficient, structured pro- 
gramming language. Developed at the Univer- 
sity of California at San Diego, UCSD Pascal uses 
English-like statements in commands. Unlike 
BASIC, Pascal program routines are written in a 
specific and orderly manner; hence, the name 
structured programming. UCSD Pascal -is less 
complex than assembly language programming 
(which we discuss next) and is faster than BASIC 
in its operation. The UCSD Pascal Compiler will 
require that a P-Code card (a circuit board) 
be added to the Peripheral Expansion System. 
Format: Disk 

Options needed: Memory expansion card, 
P-Code card, Peripheral Expansion System, 
disk drive with disk controller 
Supplier: Texas Instruments 



Assembly Language 

Many programming enthusiasts want to use 
assembly language programming on their com- 
puters. Assembly language programming is an 
advanced form of programming that uses com- 
plex instructions to perform commands. It is a 
language that is considerably more difficult to 
master than BASIC or Logo. In return for its com- 
plexity, assembly language offers greatly in- 
creased speed in program operation. 

You can develop assembly language software by 
using the TI-99/4A UCSD Pascal Development 
System Software. This is a software package 
available from Tl that requires a disk drive and a 
memory expansion card. 

The assembly language routines that you can 
develop with this system can maintain full con- 
trol of hardware interfaces, including the video 
display processor, disk drives, and RS-232 inter- 
face connections. Tl Extended BASIC also sup- 
ports the use of assembly language programs by 
allowing the programs to be linked with BASIC 
commands. 

Assembly language programming is not for the 
novice user; however, if you need the program- 
ming advantages offered by assembly language, 
you can equip your system with the Tl UCSD 
Pascal option. 



220 



CHAPTER 6 

YOUR COMPUTER'S 
NETWORK 

Now that you're undoubtedly feeling more con- 
fident about using your TI-99/4A Home Com- 
puter, you may be ready to press on, to learn 
more about how you can use your computer. If 
so, you'll want to consider going far beyond 
your home, reaching out to tap the network of 
information that exists in the home computer 
world. There are hundreds of thousands of other 
owners of TI-99/4A computers, and many of 
them have discovered uses for their computers 
that may surprise you. There are also computer 
magazines that you can read to keep informed 
and information utilities which you can connect 
to by using a telephone modem. 

99ER HOME COMPUTER MAGAZINE 

In the area of resource magazines, you'll find 
99er Home Computer Magazine to be a valu- 
able journal. Designed for users of Texas Instru- 
ments home computers, this monthly magazine 
features tutorial articles, a section on the Logo 
programming language, and a section devoted 
to games. Write to 99erHome Computer Maga- 
zine, P.O. Box 5537, Eugene, OR 97405. 



221 



INFORMATION NETWORKS 

By equipping your system with a telephone 
modem, you can connect to other computers 
over telephone lines and gain access to informa- 
tion services that provide all kinds of information 
— from the latest news and stock market quotes 
to games, restaurant reviews, airline schedules, 
and electronic mail. For an hourly charge that 
ranges from under $5 to well over $70 (depend- 
ing on the type of service and the time of day 
that you call) you can make use of information 
services that may have just what you're looking 
for. Three of the more popular services are The 
Source, CompuServe, and Dow Jones News/ 
Retrieval Service. 

The Source (a Reader's Digest company) bills 
itself as "America's Information Utility." The 
Source offers an extensively categorized bulletin 
board where you can read (or post your own) 
electronic messages. The Source provides ex- 
cerpts from 30 major magazines, the Commodity 
News Service, current and historical stock in- 
formation, and the ability to send Western 
Union mailgrams from your keyboard. The 
United Press International news service and ex- 
cerpts from US. News and World Report are 
also provided by The Source. 



222 



The Source offers a special edition of its service 
(at no extra cost) known as TEXNEI TEXNET is 
offered to owners of Texas Instruments TI-99/4A 
Home Computers. In addition to all of the nor- 
mal services provided by The Source, TEXNET 
subscribers have access to special features of 
interest to TI-99/4A computer users. These 
special features include a Tl Software Exchange 
that offers hundreds of free programs, a Tl Soft- 
ware Directory and an updated listing of all Tl 
users' groups. While over 60 games are also 
available, you'll find that The Source is generally 
a business-oriented service. 

If you prefer the more entertaining side of 
things, you may want to consider The Source's 
main competitor, CompuServe. Like The Source, 
CompuServe offers financial information (includ- 
ing the Commodity News Service and stock 
quotes); it also provides access to the Associated 
Press news wires. Unlike The Source, Compu- 
Serve is available in the evenings and at night 
only. CompuServe serves primarily the computer 
hobbyist and recreational user, with features 
that range from its large group of on-line com- 
puter clubs to its CB simulator that allows you to 
carry on conversations with people throughout 
the nation. An on-line encyclopedia and elec- 
tronic banking are also available. 



223 



The Dow Jones News/Retrieval Service is an in- 
formation service that, as its name implies, leans 
heavily toward news and detailed financial data. 
It provides information about thousands of com- 
panies scattered across many industries. Ex- 
cerpts from United Press International and the 
Wall Street Journal, current and historical stock 
quotes, and information regarding corporate 
earnings abound on this service. In the rec- 
reational area, the Dow Jones News/Retrieval 
Service has begun carrying movie reviews and 
sports updates. 

Use of these types of information sources can 
quickly become habit-forming. If you take the 
time to browse through the offerings, you'll find 
something new each time you log on (hook up) 
to your information utility. 

You need to subscribe and pay the fee to a net- 
work to be able to use it. The Source and the 
Dow Jones News/Retrieval Service are available 
at most computer stores. TEXNET is available 
through The Source at no additional charge. 
CompuServe is available at all Radio Shack Com- 
puter Centers. 



224 



PRIVATE ELECTRONIC BULLETIN 
BOARDS 

Another way to get information via your com- „ 
puter and modem is through private (free!) elec- 
tronic bulletin board systems/Electronic bulletin 
boards have been set up in most large cities 
across the U.S. You dial the phone number of the 
bulletin board, and your computer screen shows 
messages that other people have entered. You 
can also type in your own messages to be post- 
ed. Messages may be like short letters or ques- 
tions addressed either to a specific person or to 
anyone who wants to answer. Some bulletin 
boards also display ads for people selling hard- 
ware or software. The person who runs the 
bulletin board system is called the System Oper- 
ator, or SYSOR The SYSOP will try to answer 
questions and keep the bulletin board running 
smoothly. The only cost of calling a bulletin 
board is the cost of the telephone call. 

If you are interested in electronic bulletin 
boards, we are going to give you a telephone 
number to get you started. When you call this 
number, you will reach People's Message Sys- 
tems, a computer bulletin board in Santee, Cali- 
fornia. It is a free bulletin board that allows com- 
puter users to call it and exchange messages. 
People's Message Systems also lists over 400 
other active computer bulletin boards through- 
out the United States. You can display the list of 
active bulletin boards on your screen by calling 
People's Message Systems. The telephone num- 
ber is (714) 561-7227. 



225 



ADDING A MODEM TO YOUR SYSTEM 

A world of communications is available to you 
by connecting your computer to other com- 
puters by telephone. The features that networks 
such as TEXNET make available are truly excit- 
ing, but you'll need to keep in mind the actual 
hardware necessary to make the connection to 
the outside world. 

You have to know what kind of communications 
connection is used by your computer. The TI-99/ 
4A uses a connection that's known as an RS- 
232. To add RS-232 capability to your TI-99/4A, 
you'll need the Texas Instruments RS-232 pe- 
ripheral interface adapter (or a similar peripheral 
interface adapter that is compatible with the TJ- 
99/4A but is made by another company). 

An interface is simply a type of adapter. The pe- 
ripheral interface adapter will plug into the con- 
nector located on the right side of your TI-99/ 4A. 
You will also need a modem — the actual de- 
vice that connects to your telephone. There are 
many different kinds of modems; some of the 
best ones for use with the TI-99/4A are dis- 
cussed in Chapter 4. You'll want to review that 
section before you buy a telephone modem. The 
modem you buy must be attached to the RS-232 
connector (the oval-shaped connector with 25 
pins) that is located on the peripheral interface 
adapter. 



226 



Once you've inserted a peripheral interface 
adapter into your computer (or Tl Peripheral 
Expansion System) and you Ve connected the 
modem to the RS-232 connector on the periph- 
eral interface adapter, one more step remains 
before you can connect to the world. You must 
obtain software for your TI-99/4A that allows it 
to talk to other computers. The 77 Terminal Emu- 
lator II is the software that you'll use for this 
task. It comes in the form of a plug-in cartridge. 
You simply insert it into your computer's car- 
tridge slot (before or after turning the computer 
on). The software will then provide instructions 
on the screen that you should follow. 

USING THE MODEM 

When you have the peripheral interface adapter, 
modem, and software set up, you're ready to go. 
Simply dial the number of the other computer 
that you want to talk to, and when that com- 
puter answers, you'll hear a high-pitched tone 
from the telephone's earpiece. After you hear 
the tone, connect your telephone to your mod- 
em (following the instructions that were sup- 
plied with your modem). Then press the com- 
puter's ENTER key. The other computer will 
respond, usually with some type of welcoming 
message. From this point on, you can follow 
instructions and messages received from the 
other computer. 



227 



When you call any of the information networks 
we discussed earlier, it will ask you for a log-on 
or password — some sort of access code. When 
you subscribe to a network, you will receive 
a booklet that gives you complete log-on 
instructions. 

USERS' GROUPS 

You'll also want to consider the users' groups 
for the TI-99/4A. Users' groups are simply groups 
of people who share a common interest in a par- 
ticular aspect of personal computers. Users' 
groups can be an invaluable source of ideas, tips, 
and answers when you're seeking advice, trying 
to get a program you've written to operate 
properly, or looking for new and interesting 
uses for your system. 

Most users' groups meet on a regular basis, and 
the meetings are normally open to the public. 

Low-cost or free software is often available 
through the users' groups. Most groups offer a 
disk-of-the-month or cassette-of-the-month to 
members, for a minimal cost. The disk or cassette 
usually contains public domain programs, often 
written by users' group members. In many cases, 
dues contributed by group members help pay 
for the cost of a group newsletter. And it's not 
unusual to find a 60-year-old businessman and 
a 1 3-year-old student working together at a 
users' group meeting to solve a problem. 



228 



The sharing of information that is a part of the 
users' group concept can be quite an experience 
to anyone who has never attended such a meet- 
ing before. Here is a list of users' groups. If there 
is a group in your area, you should definitely 
consider joining. 

ALABAMA 

Central Alabama 99/4A Users' Group 
55 1 Larkwood Drive 
Montgomery, AL 36109 

Jasper^9/4A Users' Group 
IF North wood Townhomes 
Jasper, AL 35501 

TIBUG 

709 Nytol Circle 
Birmingham, AL 35210 

Wiregrass 99 Users' Group 
106 Harwood Place 
Enterprise, AL 36330 

ARIZONA 

Arizona 99 Users' Group 
4328 E. La Puenta Ave. 
Phoenix, AZ 85044 

Tucson 99/4A Users' Group 
6816 E. Lulerne Drive 
Tucson, AZ 85730 



229 



Yuma 99ers Users' Group 
1573 E. Kuns Court 
Yuma, AZ 85365 

CALIFORNIA 

Kings 99/4A Users' Group 
229 West Birch 
Hanford,CA 93230 

LA. 99ers Computer Group 
P.O. Box 3547 
Gardena,CA 90247 

Orange County 99/4A Users' Group 
1673 Chateau 
Anaheim, CA 92082 

San Francisco/South Bay 99er Users' Group 
16380 East LaChiquita 
Los Gatos,CA 95030 

San Gabriel Valley 99/4 Users' Group 

108 Dore Street 

West Covina,CA 91712 

Southern California Computer Group 
1 643 Coronado Ave. 
Spring Valley, CA 92077 



230 



COLORADO 



Boulder 99/4A Users' Group 
7129 Mt. Meeker Road 
Longmont, CO 80501 

Colorado 99/4A Users' Group 
Box 3400 

Littleton, CO 80161 
DELAWARE 

Delaware Valley Users' Group 
25 Quartz Mill Rd. 
Newark, DE 19711 

FLORIDA 

Daytona 99ers 

P.O. Box 4594 

S. Daytona, FL 32021 

Manasota 99 Users' Group 
6625 Roxbury Drive 
Sarasota, FL 33581 

Northwest Florida 99er HC Users' Group 
3256 Las Brisas Court 
Pensacola, FL 32506 

Tampa Bay 99er Users' Group 
13097 Lois Ave. 
Seminole, FL 33542 



South Florida 99 Users' Group 
433 Wright Drive 
Lake Worth, FL 33461 

WestJax99ers 
7266 Bunion Drive 
Jacksonville, FL 32222 

GEORGIA 

Atlanta 99/4A Computer Users' Group 
P.O. Box 19841 
Atlanta, GA 30325 

Georgia 99/4A Users' Group, Ltd. 
P.O. Box 88464 
Dunwoody, GA 30356 

HAWAII 

Aloha 99/4A Computer Users' Group 
92865 Palailai Street 
Makakilo, HI 96706 

ILLINOIS 

Chicago 99/4 Users' Group 
353 Park Drive 
Palatine, IL 60067 

East Central Illinois 99 Users' Group 
37-1 Tuttle 
Danville, IL 61832 



232 



Lincolnland 99 Computer Group 
P.O. Box 1434 
Springfield, IL 62705 

INDIANA 

Miami County Area 99/4A HC Users' Group 
163 West Third 
Peru, IN 46970 

IOWA 

Cedar Valley 99er Users' Group 
2705 16th Ave. 
Marion, IA 52302 

Des Moines 99/4 Users' Group 
3013 East 32nd St. 
Des Moines, IA 50317 

Northeast Iowa HC Users' Group 
1421 Delta Drive 
Cedar Falls, IA 50613 

KANSAS 

Mid-America 99/4 Users' Group 

P.O. Box 2505 

Shawnee Mission, KS 66201 



233 



KENTUCKY 



Kentuckiana 99/4 Computer Society 
9801 Tiverton Way 
Louisville, KY 40222 

MARYLAND 

Baltimore Users' Group 
5504 Forge Road 
White Marsh, MD 21162 

MASSACHUSETTS 

M.U.N.C.H. 
1241 Main Street 
Worcester, MA 06103 

New England 99ers 
99 School Street 
Weston, MA 06103 

Personal Computer Users 
P.O. Box 782 
Westborough, MA 01581 

Pioneer Valley 99/4 Users' Group 
3 Market Street 
Northampton, MA 01060 



234 



MINNESOTA 



Greater Minneapolis-St. Paul 
Home Computer Users' Group 
P.O. Box 12351 
St. Paul, MN 55112 

MISSOURI 

Kansas City 99/4A Computer Users 

4511N.Troost 

Kansas City, MO 641 16 

99/4 Users' Group of St. Louis 

4127 Quincy 

St. Louis, MO 63116 

NEW JERSEY 

Northern New Jersey 99ers Users' Group 
P.O. Box 515 
Bedminster, NJ 07921 

SK 99 Users' Group 
180 HaledonAve. 
Prospect Park, NJ 07508 

NEW MEXICO 

Bernalillo 99/4A HC Users' Group 
2008 Lead Ave. SE 
Albuquerque, NM 87106 



NEW YORK 

New York 99/4 Users' Group 
34 Maple Ave., Box 8 
Armonk, NY J0504 

Upstate NY 99/4A Users' Group 
P.O. Box 13522 
Albany, NY 12212 

OHIO 

Cin-Day Users' Group 
• P.O. Box 519 
West Chester, OH 45059 

Cleveland Area 99/4A Computer Group 
13771 N. Oakbrook Drive, #206 
North Royalton, OH 44133 

C.O.N.N.I. 

1456 Grandmin Ave. 

Columbus, OH 43212 

OREGON 

Pacific Northwest 99/4 Users' Group 
P.O. Box 5537 
Eugene, OR 97405 

Portland Users of Ninety Nines 
421 Northwest 69th Street 
Vancouver, WA 98665 



236 



PENNSYLVANIA 

Capital Area Users' Group 
P.O. Box 637 Fed. Sq. Station 
Harrisburg, PA 17108 

Hazelton 99/4 Users' Group 
P.O. Box 285 
Hazelton, PA 18201 

Pittsburgh Users' Group 
P.O. Box 18124 
Pittsburgh, PA 15236 

RHODE ISLAND 

Tri-State Users' Group 
P.O. Box 457 
Lincoln, Rl 02864 

SOUTH CAROLINA 

Carolina Computer Club 
225 Wynchwood Drive 
Irmo, SC 29063 

TENNESSEE 

Athens 99/4 Computer Users' Group 
2215 Congress Parkway 
Athens, TN 37303 

Middle Tennessee Users' Group 

P.O. Box 367 

Estill Springs, TN 37330 



TEXAS 



Central Texas 99/4A Users' Group 
P.O. Box 3026 
Austin, TX 78764 

Corpus Christi 99ers 
3602 Braeburn 
Corpus Christi, TX 78415 

Dallas Home Computer Group 
P.O. Box 672 
Wylie,TX 75098 

Houston Users' Group 
18103 Bambridge 
Houston, TX 77090 

SC Users' Group 
2321 Coryell Street 
League City, TX 77573 

Lubbock Computer Club 
3211 27th Street 
Lubbock, TX 79410 

The Greater Randolph 99ers 
P.O. Box 721 

Randolph AFB,TX 78148 

West Texas 99/4 Users' Group 
P.O. Box 6448, MS 3030 
Midland, TX 79701 



238 



VIRGINIA 



Tidewater 99/4 Users' Group 
942 Boiling Ave, #106 
Norfolk, VA 23501 

WASHINGTON 

Puget Sound 99ers 
P.O. Box 6073 
Lynwood,WA 98036 

WASHINGTON, D.C. 

Washington, D.C. 99/4 Users' Group 
P.O. Box 267 
Leesburg,VA 22075 

WISCONSIN 

Milwaukee Area Users' Group 
2007 North 71st Street 
Wauwatosa, Wl 53213 

Sheboygan Area Users' Group 
P.O.Box 1151 
Sheboygan, Wl 53081 

CANADIAN GROUPS 

Edmonton Users' Group 
P.O. Box 11983 

Edmonton, Alberta T5J 3L1 Canada 



Carelton Home Computer Users' Group 

John Street, RR#2 

Stittsville, Ontario KOA 3G0 Canada 

Toronto Home Computer Users' Group 
3175 Kirwin Ave. 
Townhouse #159 

Mississauga, Ontario L5A 3M4 Canada 

Victoria 99er Group 
402-1471 Fort Street 
Victoria, B.C. V8S 1Z4 Canada 

NATIONAL AND INTERNATIONAL GROUPS 

International 99/4A Users' Group, Inc. 
P.O. Box 67 
Bethany, OK 73008 

99/4 Users of America 
5028 Merit Drive 
Flint, Ml 48508 

The 99/4 Program Exchange 
P.O. Box 3242 
Torrance, CA 90510 

Young People's Logo Association 
1208 Hillsdale Drive 
Richardson, TX 75081 



240 



LEARN HOW TO 
USE YOUR COMPUTER 



This User's Guide will lead you step 
by step through all phases of 
learning how to use your new 
computer: from setting it up, to 
learning what each key does, to 
expanding your system with 
peripherals. Specific exercises 
are included for each key on your 
computer's keyboard, plus easy-to- 
understand instructions and clear 
photographs. It also provides 
software buying recommendations 
and a guide to users' groups.