For example, if you type:

*HELP

the MOS will respond with a list of the names and version numbers of the

software contained in the computer.

*ROMS

will cause the MOS to list the various systems and languages resident in the

computer's read-only memory (ROM) sockets and 'sideways' RAM areas.

Initially your computer will probably contain just BASIC and the ADFS disc

control software.

Now try typing:

*BASIC

The MOS restarts the BASIC language, resulting in the word BASIC being

displayed on the screen.

The *KEY command tells the MOS to associate a sequence of characters with a

particular function key. For example, if you type:

*KEYØfunction

each subsequent depression of f0 will produce the characters function, so

you could abbreviate the input of the phrase function keys have lots of

functions by typing:

f0 keys have Lots of f0 s

In this somewhat trivial example, the line remains incomplete (i.e. you can add

further characters to it, delete characters from it etc.) exactly as if the

characters were being typed one at a time from the keyboard. You can,

however, include a special sequence ( |M) to simulate depression of so

that a function key depression becomes equivalent to one or more complete

lines. There is also no reason why the string of characters associated with a

particular function key should not itself contain operating system commands,

for example:

*KEY 1*R0MS |M

This causes each depression of f1 to produce a listing of the computer's ROM

contents.

Other operating system commands can be used to tell the MOS to change the

way it behaves. You will recall, for example, that pressing and holding down a

key on the keyboard invokes the auto-repeat facility in which the character is

repeated after an initial delay. Both the initial delay and the speed at which the

character is repeated are controlled by the MOS and they can be changed if

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