Review of TI99/4a
by Peter Freebrey and S.M. Gee From Microchoice, published by Argus Specialist Publications Ltd.
Although the Texas Instrument's Home Computer, the TI-99/4A, has been around for quite some time, it's only
recently attracted the attention it properly deserves. There does not seem to have been the pressure
advertising that one would have expected for such a machine and the software and accessories at present
available for it.
The TI has been subject to a pretty massive price reduction in the past year and at its present cost of
around GBP 150, it would appear to be well worth considering. Another point in its favor is that it is also
widely available in the High Street — at outlets such as Rumbelows, Currys, Greens, Comet, and Argos
— and through mail order. There is no doubt which sector of the market that the 99/4A is being aimed at
— the all-in-one computer for the home environment. It has facilities for the accessories that we have
come to expect with this sort of machine (joystick controls, plug-in modules, etc.) and is intended for use
with your color television.
The 99/4A is a compact unit measuring only 15" by 10" by 1.5" which comes complete with a separate UHF
modulator pre-tuned to Channel 36 and a separate power supply unit, measuring 8" by 3.75" by 2.75". The
power supply unit and modulator have acceptably long leads to enable you to sit at a comfortable distance
from the TV — rather different from some setups requiring you to crouch uncomfortably close to the
screen. The modulator has a very short lead for the UHF output, sensible from an electronic point of view
but could pose problems with free-standing television sets. For instance, how do you balance this not
particularly light box near the set? Certainly, you must not let it hang in mid-air … must you?
Until recently, my main criticism of the TI system was the way in which it consisted of lots of separate
items. The proud owner of the TI-99/4A and its associated printer and disc drive (they call it disk … you'd
think the Americans would have learnt to speak English by now! 1) would have been faced by six separate
units (eight, if you include the Speech Synthesizer and the television). Now all that has changed and if you
opt to buy TI's purpose-designed expansion box (see below) you'll be able to keep up to seven peripherals
— including memory expansion card and interface unit — all together.
Now, let us look at what we have got and see what we can do with it. The keyboard unit is neat and
straightforward with a standard QWERTY layout, the numerals positioned on the top row of keys. I prefer
a separate numeric keypad but this is purely a matter of personal preference and one quickly becomes
familiar with whatever system is provided. Just a few hours of key-bashing and size, position, and dual
function keys soon slot into your subconscious. The keyboard is a little smaller than some but perfectly
easy to use, even by someone with fingers as clumsy as mine. On the review model, two or three keys were
a little sticky and although they had fully returned to their rest position before I got to pressing the next
key, it did leave a nagging worry as to whether one day they would stay down!
Good quality sockets are used to connect to the power supply, modulator, tape recorder, and remote
controls (joysticks, etc.). The sockets for tape recorder and remote controls are the same type and size and,
although I'm sure TI will have protected the appropriate circuits, it surely would have been more sensible
to use a different type. Neither are the sockets labeled in any way and, bearing in mind that this is aimed
at family use, I think some form of unique connectors should be the rule.
The case is made from metal covered plastic and as it does not seem to have any brittle areas, it should
be safe for children to use — an important consideration for a home computer which all the family are
likely to want to use. Another point on which it cannot be faulted is the keyboard mounting — it's well
supported and so will stand up well to the treatment it's likely to receive. Are you wondering what I have
in mind? Well, imagine playing an exciting game of zap the alien — you don't exactly stroke the keys with
As already mentioned, in general, the connectors on the TI-99/4A are of a high quality. It is especially
worth commenting, however, that the program module plug-in slot is very well engineered and that I had
no problem inserting or removing program modules.
Inside the case there are two PCBs. The smaller is the power supply, which appears to be switched mode.
In any case, it runs cold and is well made, which is the point to note. The larger of the two boards
constitutes the computer itself and one of its important features was apparent the moment I took the lid
off — it's actually shielded by a metal casing. What a wonderfully simple way of reducing radio interference
and thereby improving picture quality. Full marks to TI for a good idea. But won't it run awfully hot? Well,
TI have taken the steps necessary to cope with the problems as I discovered once I lifted the tin shield off
— two of the chips had been coated with a sticky white substance which I guessed served to make thermal
contact with the metal in order to transmit excess heat through it.
Only after removing this shield do you get to the main board itself. The board is dominated by the huge
TMS9900 16-bit microprocessor which in itself is rather a puzzle. Why, when TI has had a 16-bit
microprocessor — yes, the type we're now getting excited about — available all this time hasn't it beaten
all-comers to producing the super-micros which are only now appearing on the scene?
To return to our examination: Although there were a number of long jumper wires on the review model,
this did not seem to indicate last minute modifications and overall I was impressed by the layout of the
board. The 16K of RAM is provided by eight 4116 chips and there are two 128 byte RAMs for use as
temporary storage. There are also two ROMs containing the Basic.
After connecting up and switching on, I must admit to being quite impressed with the display. The initial
display consisted of a number of colored rectangles, together with the Texas Instruments' trademark (logo)
and the words: HOME COMPUTER READY, PRESS ANY KEY TO BEGIN. The colors were stable with
a small amount of color fringing and, unlike some experiences with other computers, gave the impression
of a steady businesslike display. On pressing "ANY KEY" you are presented with a menu:
1 FOR TI BASIC
Should you have any of the TI software plugged in, the menu will, of course, be extended to include the options
available. The "plug-ins" are called command modules and are plugged in by sliding the cartridge into the
recessed tray at the right of the keyboard.
Command modules should only be inserted or removed when the
machine is in its initial quiescent/waiting mode of "PRESS ANY KEY TO BEGIN" (known as the "Master
Computer Title Screen"). You may return to this mode at any time by pressing the FCTN and = keys
simultaneously, or by entering BYE. The latter is recommended as it first closes all open files, then erases
all programs and variables in the memory, finally resetting the computer ready to return it to Basic when
required. The FCTN = (QUIT) command does not close any files but is used when you have a command
module in operation and no opportunity to type BYE (most of the keyboard is disabled for many of the
The full display area of 32 characters across by 24 high may only be used by graphic symbols, and an area
of 28 × 23 can be used for PRINT statements or LISTings. Any program line may be up to four screen
lines in length (112 characters including the line number). The computer is fairly user friendly although
it does demand spaces in the right places. For example:
are all unacceptable, whereas:
20 PRINT A
are acceptable statements. It will display a number of error messages should you ask it to do something
Certain errors are detected on entering a command in a program line. Entering:
gives the message INCORRECT STATEMENT as there is no space between LIST and 100, and entering
an edited line which exceeds the memory capacity, gives the message MEMORY FULL.
The computer will accept program lines which are incorrectly written and entered, but when you RUN
the program, it will come to a dramatic halt (crash) on reaching the line. These errors may be detected in
two ways. First, on RUNning the program but before the program lines are actioned, the computer scans
the program in order to establish a "symbol table". This is an area of memory where the variables, arrays,
functions, etc, are stored. If the computer detects an error during this scan, it will display an ERROR
message, e.g. FOR-NEXT ERROR, telling you that the program has a mismatched number of FOR-NEXT
While displaying this message, the screen remains in its programming mode color of light blue.
Should this memory scan prove acceptable, the program is then RUN and the scan becomes a light green
color while the program is RUNning. During the program RUN, PRINT statements, etc, are displayed as
black letters on the same green screen, unless programmed for a different combination. At this point, the
computer has accepted the scan but, in the process of RUNning the program, further errors can still cause
a crash. The screen then reverts to light blue and an error message along with the line number at which
the crash occurred will be displayed For example:
BAD LINE NUMBER IN LINE 320
indicates that a jump was made to a non-existent line in the program.
One fact which you cannot help but notice if you've used many other microcomputers, is that the TI-99/4A is slower than a number of machines on the market today (see Micro Choice results of the benchmark
tests) but for the vast majority of uses it will be put to, I doubt that the users will mind too much.
Nowadays, a lot of stress is put on the speed a computer will work at. Of course, this is important, but
what are you going to use this computer for? As a dedicated scientific computer to work our formulae
containing hundreds of steps … I doubt it. (However, if accuracy and precision are qualities you are
looking for, you'll be glad to know that your calculations will be correct to 13 digits!)
TI Basic has a number of commands/statements which some machines do not have, and one or two that
are not in its vocabulary. I was pleased to find: RESEQUENCE, renumbers program lines; TRACE, lists
the program line number as it executes that line; NUMBER, gives you automatic line numbers when
writing a program; as well as ON … GOTO, and IF … THEN … ELSE which are not always present in
The string handling capabilities seem to be quite reasonable and the arithmetic functions all that one
normally expects. A slightly unusual array handling command is OPTION BASE allowing you to set the
lower limit of an array to either 0 or 1. This can be quite useful to those of us who get confused dealing
with complicated array handling while trying to remember that the 15th element in an array is
represented by A(14) and not A(15)! OPTION BASE is definitely the easy way out!
Missing from what is otherwise a pretty comprehensive line-up of commands/statements are PEEK and
POKE. This is nowhere near as desperate as some people make out, because users of this machine would
probably not be wanting to delve into memory locations. However, for those of you who may wish to
interrogate the display screen, TI Basic presents us with CALL HCHAR, CALL VCHAR, and CALL
GCHAR, of which more shortly.
To clear/erase the screen, whether in immediate or program mode, the CALL CLEAR command (TI Basic
calls it a subprogram) is used. CALL in TI Basic can be followed by a number of keywords:
Allows you to define your own special graphics characters. You may redefine the standard set of
characters and codes 128-159. The characters are made up of up to 64 dots in an 8 by 8 grid allowing
a varied set of special characters to be used … memory permitting.
Allows you to display on the screen a specified character at a specified location (defined by row and
column) and will repeat that character horizontally for a specified number of times.
Similar to HCHAR, VCHAR repeats the character vertically rather than horizontally.
Defines the screen color on which individually colored cells are displayed (CALL COLOR) then defines
the foreground and background colors of that cell).
Allows you to transfer one character from the keyboard directly into your program. It is similar to
GET or INKEY in other Basics, but is slightly more sophisticated as certain keys may be disabled if
Allows you to read a character from the screen, the location required being specified by row number
and column number.
Allows you to generate a tone between 100 Hz and 44,000 Hz. You may define the duration in
milliseconds and the volume on a scale of 1 to 30. Further, you may generate up to three tones plus
one noise to be played for the same duration at the same time (i.e. three-note chords, etc.) all with
their own specified volume levels! You also have the option of various "white noise" effects.
Allows the input of information based on the position of the joystick lever or the fire button on the
Wired Remote Controllers which are an accessory for the TI-99/4A.
The TI-99/4A will allow assignment in both the now somewhat obsolete LET A=n or in the more common
form of A=n. In which case, why bother to type in those extra letters?
The TI-99/4A has 16K of user RAM expandable by an additional 32K to 48K — or even to 52K by the
addition of the 4K Mini Memory plug-in module. However, this is only accessible to an appropriate
command module or accessory.
TI suggest a domestic audio cassette recorder at the top of their list of
accessories you might like to add to your TI-99/4A. They recommend two
inexpensive, readily available tape recorders for this purpose. They are the PYE
9110 and the Sanyo Slimline, both available for around GBP 20.
If as well as saving programs you want to list them as "hard copy", you'll be
pleased to discover that there is the TI Solid State Thermal Printer which can
be plugged in directly to the computer. This uses a narrower than usual paper
which is heat sensitive and will accept 32 characters per line. Its useful features
include 32 pre-defined graphics symbols and the ability to cope with plotting.
As previously mentioned, the latest development is the Peripheral Expansion
System which is a unit measuring 20" by 15" by 14" and has eight slots for
peripheral cards. one of these is used to connect the system to the computer
console, which means you have seven left for use. The 32K RAM memory
expansion card is one which could be slotted in. Another is the RS232 Interface
card which includes a parallel port suitable for driving a printer with a
Centronics-type interface. The RS232 card really opens up the world of other
manufacturers' printers to the TI owner. There is also a p-Code card containing
the UCSD p-Code interpreter in ROM. This, used with the UCSD Pascal
software package, changes the machine into a Pascal development system
without using up any additional RAM.
The PEB provides space for installing one TI disk drive but another two disk
drives can be added externally. The current disk controller is for 5.25"
single-sided, single-density units, although double-sided, double-density units are
to be catered for in the future.
The TI Solid State Speech Synthesizer plugs directly into the right-hand side of
the computer itself. This contains a vocabulary of words and phrases,
permanently stored on chips. It can be used in conjunction with a command
module — see below for comments on Speech Editor — and speech can be
incorporated into the user's own TI Basic programs.
On the soft side
As far as software is concerned, by Autumn 1982, TI offered 66 packages,
cassette tapes, and plug-in modules. The plug-in command modules range
through various games, a number of educational titles, and a Speech Editor to
a Disk Manager and TI Extended Basic.
The games include the inevitable "TI Invaders" and various other "shooting"
games set in different scenarios. All offer more than one difficulty rating and all start at a difficulty rating high enough to make them interesting and reasonably addictive.
Car Wars is simply two cars in plan view racing around concentric tracks, one car "eating up" a series of
dots as it goes. You may change tracks at north, south, east and west and the second car is programmed
for a head-on collision … you have to avoid it! A very simple game but requiring quick reactions and very
Hunt the Wumpus is a game of logic to find in which cavern the Wumpus is hiding. You get clues as you
explore the caverns … it isn't difficult but the Wumpus seems to eat up its opponents all too often! Good
fun and it certainly makes impetuous youngsters think ahead.
Video Chess has good graphics and although it sometimes plays some very strange moves, you cannot
afford to take it lightly. You may choose its type of play (aggressive, normal, or defensive) and the level
of play. A good club player should be able to beat it, but may get the occasional surprise.
Connect Four is a real brain-teaser and, like several of the other games, may be played by either one person
against the computer or as a two-player game. Against the computer you have several levels of difficulty
and I enjoyed it immensely. My only criticism is that of its psychological one-upmanship … when you place
a 'token' on the grid it sounds a minor "ker-thonk" but every time it places a token, you get a little tune
that gives the impression of "rah, rah, rah … so there, beat that!". An excellent game.
The Speech Editor is fun, but although its vocabulary is quite large (more than 300 words) I'm afraid I
found this the least interesting of the plug-ins. The words are clear (with American accent) and it is
possible to build words from those already built in, but I found that whenever I wanted a special word, it
was not possible to make it up. Obviously I am a visual rather than audio oriented person.
The child education tapes are rather repetitive to a grown-up, but delight the little ones especially when
they get a gold star and some stirring music when they solve their problem. These cover Pre-School Early
Learning, Early Reading, Beginning Grammar, and Arithmetic.
Household Money Management is quite involved, with many questions regarding how much you earn and
where it all goes. It takes some time to set up accurately, which, of course, you must do if you wish to take full advantage of its capabilities. It is a little depressing as, although I know I only have about one pound at the end of the month, I'm not so sure I want to see it boldly stated on the screen. Also, I'm not so sure it wouldn't be quicker to work it out on the back of an envelope!
The Disk Manager enables you to use the TI Disk Drive via the Disk Controller and in the brief time I used
it, it seemed to function perfectly. The drive is a little noisy in operation and when it read my first disk
I had visions of the floppy being shredded, but nothing untoward has happened so far.
TI Extended Basic offers a number of additional commands/statements and facilities which make it a very
useful extra. Multi-statement lines are allowed — which make life a little simpler when writing a program.
It has an interesting command called CALL SPRITE. This enables you to create moving graphics very
simply. This module also has a PEEK subprogram which, with other commands, allows access to Assembly
Language subprograms 7 (of little interest to the initial buyer of the TI-99/4A but could be of great value
as his/her computer awareness grows).
In all, there are more than 40 new or expanded commands in TI Extended Basic and although the
standard TI Basic is quite comprehensive, this module will certainly open up new horizons for the addict.
Did someone mention instructions? Home computers are notorious for their poor instructions/manuals
but here Texas Instruments have produced something definitely in the superior bracket.
The User's Reference Guide (A4, 170 pages) starts with. Section I, General information, explaining clearly
and with a number of diagrams what you should have to do to get the system up and running: how to
interconnect the various units, what additional accessories are available and, most important of all, a brief explanation of keyboard and special function key operation.
The special function keys have a further short section to themselves amplifying the previous information.
These keys, FCTN and CTRL, are used as special shift keys giving such operations as cursor control, insert
and delete character and erase line. Entering control characters (CTRL key) also enables to TI-99/4A to
link in with various telecommunications devices.
Section II, entitled Basic reference section, takes the reader through such basics as numeric constants,
variables, string expressions, reserved words, etc, to a complete listing of all the TI Basic words understood by the TI-99/4A. These are grouped together under sub-headings such as "Commands", "General program statements", "Color graphics and sound", "Built-in string functions", etc. Each TI Basic expression/word is explained clearly with plenty of examples to hammer the point home.
Section III, Appendix to Basic reference section, contains such items as ASCII character codes, keyboard
mapping, color codes, error messages, and some applications programs.
There are eight further short sections. One worthy of mention is a fairly comprehensive index providing
such information as a glossary, how to use pre-recorded software, various addenda, very simple fault
finding (e.g. have you plugged into a mains outlet?) and the UK guarantee!
In conclusion, I can only say that I have enjoyed having the TI-99/4A in my home. My children, aged six
and seven years old, have enjoyed both the games and the educational modules. Although the younger
child could cope rather easily with all but the grammar module, it has been educational to see just how the
use of the computer can hold the interest and, in turn, make young children aware of computers.
The TI-99/4A is certainly a good contender for a home entertainment unit. Whether it stands up as a
complete computer system is, however, still an open question. The advent of the PEB and the variety of
peripherals now available suggest that TI want you to consider it seriously as a fully expandable machine.
— With thanks to Argus Specialist Publications Ltd.
By Howard Greenberg
Hello and welcome to a new writer in a new user group magazine. My name is Howard and I'm the
cheapskate's answer to Computer and Video Games monthly. Those of you who don't care for my style of
writing needn't feel inadequate for finding it trivial /unreadable/nauseating/not worth the paper it's written on. I'm simply not a professional writer. Since some of you may wonder why I've picked the easy job, my qualifications are simply that I work in the amusement industry. As such I have access to all the latest games, news, and developments to and within the video games industry. I know what's next in amusement
arcades and what's likely to appear on home computers.
Certain games will never appear on home computers. Many will never appear on the TI-99/4A — at least
not in their original form. Copyright is being more clearly established and with one half of the industry
suing the other, no one is looking to market someone else's game. At least, not without going through the
proper channels first. For example Atari now have first refusal to adapt all Williams games (Defender,
Robotron, Joust) for their own computers. If someone wants to write a program to play Joust on their
TI-99/4A that's fine. But if you try selling that program … well I'll come to your trial and wish you well.
Some of you may be unfamiliar with some of the older games, so I've listed here those games that had a
significant impact on the amusement industry, together with any own comments.
Pong (or ping pong). First coin-operated game. Similar to a game of tennis. Eventually made as home
machines. No longer made, probably no longer played.
Breakout (Super Breakout). First game to capture the public's imagination in a big way. Similar to Pong
except that the object in hitting the ball was to dislodge a brick in a wall. Still available for Atari VCS.
Space Invaders. A particularly nauseating game. You either love it or hate it. Now synonymous with
video games. First entry from Japan to score well in the West. Still available for probably every machine
capable of playing games.
Asteroids. Atari's best seller so far. Their first game to use the X-Y monitor. small ship in the middle of
the screen surrounded by asteroids moving at random. Shoot one of the rocks before it crashes into you.
Available for Atari computers. TI version, Pesteroids, from Stainless Software (needs XB).
Lunar Lander. One of Atari's worst sellers. The object was to land a lunar module on the Moon. (Where
else would a lunar module be going?) The program, although heavily modified, was originally written by
NASA for a use not dissimilar to the name of the game. I'm not kidding. Despite poor sales in amusement
machine form (so poor that if you want one they can be bought for as little as GBP 50), it has proven very
popular with home computer users. Only the TI-99/4A doesn't have a version. Well, it does, but it's in Basic
and that's just too slow.
Night Driver. One of the many driving games made by Atari, this was one of their best despite poor
graphics (by today's standards). The car was printed on the screen front, with the road represented by cat's
eyes. The object was to stay on the road. Available for VIC-20.
Monaco Grand Prix. Made by Sega and definitely one of the best driving games made. Viewed as a plan
(looking down on the car and road) you had to race your car through Monaco, passing kamikaze drivers,
going through tunnels with only headlamp vision, through chicanes, and various other obstacles.
Fantastically expensive due to very high component count. It had no fewer than seven logic boards. Not
available for home computer use although various parts of the game have been used.
Missile Command. One of Atari's best and my personal favorite. You are given six cities to defend with
three launching bases. Each base has 10 missiles to knock out the attacking missiles thrown at your cities.
Probably so enjoyable because each game was a new test. Available for Atari and BBC.
Defender. Williams' first entry into the video game market. A well-established pinball manufacturer, they
decided to enter the video games market with spectacular results. Probably the video game with more
controls than any other.
Scramble. Konami's major contribution to video game history. The game appeared similar to Defender
but was not nearly as good. Available for most home computers. TI's Parsec is a combination of Scramble
Pac-Man. The first game in a long time that didn't involve blasting space ships to atoms. If you haven't
played this you haven't lived. Its appeal probably is in its humor. Available to everyone with a computer.
TI-99/4A version is Munch Man.
Donkey Kong. Couldn't be called King Kong because of the film of the same name and plot. Rescue the
damsel in distress from the top of the Empire State Building while the big ape is chucking barrels down
at you. Great fun. Available for most machines (but not TI).
Tempest. Atari's first color X-Y game. Basically Asteroids in reverse, with you on the outside defending
yourself against the enemies coming out from the center. A superb game, not much appreciated mainly
because so few were brought into the country primarily due to Atari's lunatic pricing policy. So far only
available for the Dragon. (Yuk.)
Astron Belt. I must confess to not having seen this game yet. Nonetheless, it must rank as a very big first
for Sega. This is current state-of-the-art technology. It is unlikely to ever appear on home computers
except in very cut-down form. Why? Because it uses interactive video discs to give a picture as good as your
television set. There are only four in the country at present (One's in Brighton Clive!) and they're very
expensive. 40p a play is a bargain considering their purchase price.
That's just my list of games. You may feel I've ignored your favorite or glossed over it. If that's what you
think, write in and say so. My address is under the Arcade Hardware advert. Never mind being alert, we've
enough alerts for the time being. What we need are writers. I don't know who else apart from Clive and
Audrey are doing the writing in this rag, but a few extra articles wouldn't go amiss. Or a Ms. or a Mr.
Whaddya mean you don't know anything technical? Did you see anything technical in this article?
Just a little note to all of you who do play video games. If you can't make it to the fourth screen or that last little demon just won't lay down and die decently, don't abuse the machines. They represent a considerable investment on the part of the owner. Would you like your TV smashed because a guest couldn't watch his favorite program? If you think that we're coining money hand over fist, anyone who wants to is welcome to buy shares in our company. If you enjoy playing games, all well and good, just don't play with them.
I'm not signing off here as there are a few other points I want to raise and hopefully raise a response from
someone out there. Is there anyone out there?
Stop Press. Atari is converting three of its computer games to run on the TI-99/4A: Pac-Man, Centipede,
and Defender. These will be on sale by the end of 1983 in cartridge form. — Ed.