AMSTRAD CPC464, User Manual

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2.4 Running the Welcome tape
The tape supplied with the CPC464 contains a number of demonstrations of the sound and graphics
capabilities of the computer and its built-in software – the AMSTRAD BASIC, and the Machine
Operating System. (MOS)
Part of the function of the machine operating system is the cassette operating software itself, which
includes a series of brief commands that read and write data and programs on to the tape. The most
frequently encountered are the LOAD and RUN commands.
To make operation of the computer as simple as possible, the CPC464 includes a number of special
functions that simplify the keyboard entry until you’ve had some practice with the keyboard. If you
have switched the computer on and are looking at the ‘wake up’ screen message, with the computer
prompting you with the word:
Ready
Insert the tape as shown (figure 2.1), reset the tape counter to 000 by pressing the small button
alongside the tape counter window, and press the control
[CTRL]
key and then whilst still holding
this key down, press the small
[ENTER]
key at the bottom right-hand corner of the number-only
keypad. You will be prompted by the message:
RUN"
Press PLAY then any key:
For your information, this is the an example of the expansion token, first encountered in the
KEY
command briefly introduced in Chapter 1, where the computer is instructed to perform a complete
command sequence using a shorthand form of keyboard entry to speed up simple and frequently
required instruction sequences.
You could have typed in the RUN” instruction - and then pressed the
[ENTER]
key, but it is easier
to use just 2 keystrokes to achieve the same results.
For most purposes, the two
[ENTER]
keys perform the same task - but there are circumstances
where the smaller of the two keys can be altered (redefined) to some other operation using
instructions from programs. The subject of ‘User Defined Keys’ will be covered in more detail later
on.
The
[PLAY]
key you are being prompted to press is the key on the cassette drive mechanism. Press
it now until it ‘latches’ and stays down. The part of the prompt message that asks you ‘press any key’
is a commonly used phrase in computing that can mislead the unwary. It is used to simplify
sequences that instruct a program to get on with the next operation by avoiding the need for further
specific instruction keywords.
It would be more correct to say ‘press any key - other than the
[SHIFT][CAPS LOCK][CTRL][ESC]
keys (or any of the keys on the cassette sub-panel)’ - but all computers inevitably have to make
certain assumptions in the interests of simplicity. Wherever the term ‘press any key’ occurs in this
user guide (or in programs supplied by AMSOFT and other vendors), assume the exceptions outlined
above still apply.
The key you press will not result in a character appearing on the screen, it will simply cause the tape
motor to start playing the tape. If the tape does not start - press another key (it’s a good habit to use
the large
[ENTER]
key) and check that the
[PAUSE]
key has not been accidentally pressed down.
If you type more than one key, the computer will discard any other keystrokes once it has started to
load the program.
Note that you have not specified any particular program name. As long as nothing else occurs on the
same line immediately after the