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(NOTE: This refers to a UK Console on 240 volts AC with standalone PAL modulator, and 1980 tv and electrical standards)

This information is included in the manual supplied with your console (link is to 1300k pdf file at, but is supplied here, in a slightly different format, to provide you with a central source of information.

Unpack the console carefully. The power supply and television modulator are separate units packed with the console.

If your dealer has not fitted plugs onto the power supply cable, you should attach a mains plug fitted with a 3 Amp fuse.

The power supply may become quite warm, so place it where high temperatures can cause no damage. It will be out of the way if you place it on the floor, preferably not on a carpeted surface.

You may find that you will use the console for many hours at a time, so give careful consideration to its location: a table or desk with a firm top and room for you to spread your papers and books. You will need a chair which allows you to sit comfortably without backache.

If you wear glasses, the tv will not be located at the most comfortable distance whether you are near or short sighted. You cannot damage your eyesight using the computer, but the use of glasses prescribed for the distance of your tv set when you compute, will alleviate problems of eye strain.

The tv modulator connects your tv to the console. Plug the 'DIN' audio plug into the computer and the coaxial plug into your tv. You will need to tune your tv to Channel 36, and it is essential that your tv is able to 'fine tune'. If you have problems, ask your dealer. Some fringing occurs on some colours: this is normal, but you should tune your set for the sharpest picture you can which does not introduce heavy diagonal lines over the entire picture.

When the console has been connected to the mains and to your tv, you may switch on and adjust your tv set for best reception. When properly tuned, the computer sound output should be heard on your televisions loud speaker. It may be necessary to slightly adjust the tuning. To produce a sound output, press any key (except SHIFT,FCTN,CTRL, or ALPHA LOCK) so that the tv display changes to:

Instead of pressing 1, press the space bar, and a brief error tone is produced. If you have difficulty adjusting the tuning to provide both sound and picture together, your television may be unsuitable, and you should consult your dealer.
Your computer is now ready for use. Press Key 1 and you are ready to key in a program in TI BASIC.

If you wish to use a TI Module, push it gently into the slot at the right hand side of the computer. The tv screen will flicker and the 'test card' will reappear. Press any key for the 'menu' to select TI Basic, or the contents of the module.

You may need more than one attempt, as module contacts can become tarnished or grimy. If the computer ceases to respond, it is a 'lock out', something which happens with all computers. Do not panic - switch the console off and try again.
DO NOT touch the printed circuit board contacts in the module or you may destroy the electronic components within.

Your computer is capable of much, but requires a little help. It can do nothing unless it is first programmed either by inserting a preprogrammed module, or keying in a program, written by yourself, or from a magazine.

BASIC (the name given to the 'language' most home computers are programmed in) was once quite standardised, but with each new computer adding new commands, and new features, there is now a great difference in the versions of Basic used in different computers.

Your TI99/4A uses TI BASIC, and your computer can only understand programs which are written in TI BASIC.

BASIC is very similar to English, using common words to instruct the computer what to do, but the computer is very precise in its requirements for the way those instructions are keyed in.

Each command word is separated from any other word or number by a space. Some computers permit you to leave out spaces, but in order to allow you a wide choice of variable names, your 99/4A needs to see those spaces. If you put in a space where one is not required, the computer often removes it itself.

Take special care when entering the number 1 or the letter I, and the number 0 and the letter O. These can very often look similar in magazine listings.If you use the wrong one, the computer will usually be unable to RUN the program, and halt with an error message, such as BAD VALUE or STRING-NUMBER MISMATCH.

If the printed program contains DATA lines, check them thoroughly, as one comma too many or too few can cause a "program crash" when you try to RUN the program you have entered.

Learn to use the SHIFT key on the left : if you use the key on the right of the keyboard the inevitable accident will occur and instead of entering a + (SHIFT and =) you may press the FCTN key and the = . This will cause a system reset and you will lose your program.

Take note of the spaces in the printed program: if one is printed, you should enter it!

Listings will run if entered carefully, but occasionally a misprint occurs, or sometimes whole lines will be omitted.

If you do encounter problems, carefully check each line you have entered. Information on 'debugging' or correcting programs can be found in the section on 'How to use TI Basic'

Normally you should key programs in with the ALPHA LOCK key in the DOWN position, unless the listing clearly uses lower case letters, in which event release ALPHA LOCK when entering those letters.

THE INFORMATION IN THIS BOOK IS FREE. It may be copied, distributed and/or modified under the conditions set down in the Design Science License published by Michael Stutz at
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