by Steven Vickers and Robin Bradbeer
PDF Edition 2004
prepared by Colin Woodcock, ZXF Magazine (www.zxf.cjb.net)
© 1982 Amstrad
Amstrad has kindly given its permission for the redistribution of its copyrighted material, but retains that copyright.
Front cover illustration by John Harris of Young Artists
Contents
CHAPTER 1 CHAPTER 2 CHAPTER 3 CHAPTER 4 CHAPTER 5 CHAPTER 6 CHAPTER 7 CHAPTER 8 CHAPTER 9
The computer and setting it up. Page 5
The keyboard. Page 8
Numbers, letters and the computer as a calculator. Page 11
Some simple commands. Page 14
Simple programming. Page 17
Using the cassette recorder. Page 21
Colours. Page 25
Sound. Page 27
Inside the case. Page 29
1. The Computer and setting it up
This short booklet has been written for two types of people. First, those who know nothing, or next to nothing, about computers, and, secondly, for those who are familiar with computer based systems but who like to read instruction booklets before plugging anything in.
There is a second, thicker book which is the BASIC programming manual. This should not be read by the novice computer user until this booklet has been read and understood.
Unpacking the ZX Spectrum, you will have found:
1 This introductory booklet and the BASIC programming manual,
2 The computer. This has three jack sockets (marked 9V DC IN, EAR and MIC), one TV socket, and an edge connector on the back where you can plug in extra equipment. It has no switches - to turn it on you just connect it to the power supply.
3 A power supply. This converts mains electricity into the form that the ZX Spectrum uses. If you want to use your own power supply, it should give 9 volts DC at 1.4 A unregulated.
4 An aerial lead about 2 metres long, which connects the computer to a television.
5 A pair of leads about 75 cms long with 3.5 mm jack plugs at each end. These connect the computer to a cassette recorder.
You will also need a television - the ZX Spectrum can work without one, but you won't be able to see what it is doing! It must be a UHF television (in the UK); if it is not built to receive BBC2 then it is no good. As its name implies, the ZX Spectrum gives a colour signal which if you have a colour television, will produce a colour picture. If you only have a black and white television, then the colour will appear as black, white and six different shades of grey; but apart from that, a black and white television will work just as well as a colour television.
The components of the system should now be interconnected thus:
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Chapter 1
Mains |
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Power |
electricity |
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supply |
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unit |
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Mains lead |
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TV mains lead
TV
TV EAR MIC 9V DC in
UHF
Aerial
Socket
Figure 1
If your television has two aerial sockets marked UHF and VHF, then use the UHF one (UK).
Turn the power on and switch on the television. You now need to tune the television in The ZX Spectrum operates on channel 35 UHF (UK) and when it is first plugged in and properly tuned it gives a picture like this:
Figure 2
When using the computer, you will probably want to turn the volume on the television right down.
If your television has a continuously variable tuning control, then you just have to
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Chapter 1
adjust it until you get the picture shown in figure 2. Many televisions now have an individual push button for each Station. Choose an unused one and tune it in.
For use in countries that have a different TV system to that in the UK a version of the ZX Spectrum specially designed for that system is necessary. The UK uses a UHF system with 625 lines and 50 frames per second. It also uses a colour encoding system called PAL. Most countries in Western Europe (except France) use a similar system, and the computer should operate in these countries without any modification. The USA, Canada, and Japan, for example, use a totally different TV system and a different version of the computer is required.
When you turn the ZX Spectrum off, all the information stored in it is lost, One way of keeping it for later is by recording it on a cassette tape. You can also buy tapes that other people have prepared and so run their programs. The lead with two jack plugs at each end is used to connect a standard cassette recorder to the ZX Spectrum. Chapter 8 of this booklet explains this further.
Now that you have set up the computer, you will want to use it. The rest of this booklet tells you how to do that; but in your impatience you will probably already have started pressing the keys on the keyboard, and discovered that this removes the copyright message. This is good; you cannot harm the computer in this way.
Be bold. Experiment. If you get stuck, remember that you can always reset the computer to the original picture with the copyright message by taking out the '9V DC IN' plug and putting it back again. This should be the last resort because you lose all the information in the computer.
WARNING. Do not try to use the ZX 16K RAM with the ZX Spectrum. It will not work.
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2. The Keyboard
The keyboard of the Spectrum is very similar to a standard typewriter. The letter and number keys are in the same place; however each key can perform more than one function. On a normal typewriter the letters appear in lower case, and when used in conjunction with the shift key, appear as upper case (capitals). The Spectrum keyboard is just the same.
To help you know what mode the keyboard is in, a reversed out (white on black) letter appears on the screen indicating the position of the next character that appears when a key is pressed. The letter is flashing to distinguish it from any character already on the screen. It is called the cursor.
When first switched on the Spectrum shows a copyright message on the screen. Pressing any key brings up the word printed below the letter on the key, (this is called the keyword). This is because the computer is expecting a command from you to tell it what to do and all commands must begin with a keyword. Unlike most other computers the Spectrum allows you to enter keywords with only one key depression.
For example, if the P key is pressed immediately after turning on, the keyword PRINT appears on the screen. The “ symbol is marked on the P key as well. To get it, you must press two keys at once; hold down the SYMBOL SHIFT key, which is near the bottom right-hand corner of the keyboard, and while still doing that, press the P key.
Figure 3
The cursor now changes to an L, as a Letter is now expected by the computer. Type in the letters "Hello". If there is already some other text, for example, on the screen turn the computer of (remove the 9V plug) and start again. Use the CAPS SHIFT key to get the upper case H. In general, anything coloured white above the key requires CAPS SHIFT to access, and anything coloured red on the key requires SYMBOLS SHIFT
A command beginning with PRINT tells the computer to write the letters enclosed
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Chapter 2
in the double quotation marks onto the screen. For this command to be executed by the computer, the ENTER key must be used. When this has been done the screen should display the word
Hello
and some other characters. (A flashing question mark indicates a mistake somewhere. If this happens start again and repeat the exercise). The message at the bottom is really the computer reporting back that everything has gone 'OK'. The message is important when running programs but can be ignored at the moment.
Notice something else: The letter O and the numeral 0 are represented by different characters. It is important to remember this, The numeral 0 always has a line through it. The computer will always interpret the letter O as a letter, so don't press the wrong key. Similarly, the numeral 1 and the lower case letter L are different and unlike some typewriters, these cannot be interchanged.
As the keyboard mode is so important to understand it is useful to summarise what happens once again.
The flashing character L is called the cursor. It shows whereabouts on the screen the computer will put the next thing that you type. It is not always an L; if you turn the computer oft and on and then press ENTER the copyright message will change into a K cursor. The letter that it uses tells you how the computer will interpret the next thing that you type. At the beginning of a Line it will be a flashing K standing for 'keyword'. (The copyright message and reports also count as a flashing K) A keyword is one of the computer's special words, occurring at the beginning of a command to give the computer a general idea of what the command is going to tell it to do. Since the computer is expecting a keyword at the beginning of a line, when you press - say - the P key the computer decides not to interpret this as a P but as PRINT; and it warns you that it is going to do this by making the cursor a K. When it has the first keyword, it doesn't expect another one so what you type now will be interpreted as letters. To show this, the computer changes the cursor to an L - for 'letter'.
These different states are often called modes - we shall talk about keyword (or K) mode, and letter (or L) mode.
If you want to type a lot of capital letters without holding CAPS SHIFT down, you can make all letters come out as capitals by first pressing CAPS LOCK (CAPS SHIFT with 2). To show this is happening, the L cursor will be replaced by a flashing C (for ‘capitals'). To get lower case letters and the L cursor back, press CAPS LOCK a second time.
(If you press CAPS LOCK during keyword mode, you will not immediately notice any difference, but you will see the effect after entering the keyword when the computer will be in C mode instead of L mode).
As well as keywords, letters, numbers and various programming and scientific expressions, the keyboard also has eight graphics characters. These appear on the number keys 1 to 8, and can be printed onto the screen in a similar way to letters and numbers. To do this the keyboard must be changed to graphics mode. This is
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