AMSTRAD CPC464, Руководство пользователя

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The computer automatically sets itself to read the rate at which the tape has been recorded. When
SAVEing a program, you need to instruct the computer if
you
wish to use the Speedload rate, or it
will default to the Supersafe speed.
To select the higher rate to save your programs and data, check you are in direct mode (the R
eady
prompt displayed), and type:
SPEED WRITE 1
to return to the default speed, you can either reset the computer (in which case all data will be lost,
or you can type (at the R
eady
prompt):
S P E E D W R I T E 0
2.6 Saving programs and data on the cassette
BASIC has several commands that are concerned with the way in which data is written onto the
cassette. They are summarised briefly here, together with examples.
2.6.1
SAVE “<file
name> ”
The most straightforward method of saving data onto the cassette is to use the command SAVE
when the CPC464 is displaying the Ready prompt after executing or listing a program. Using the
example of a brief program that lists the displayable characters discussed in Chapter 1 as the object
of our SAVE command.
The <file name>, can be any combination of 16 keyboard characters (including spaces). If you try to
enter a longer name, the 17th and subsequent characters will be discarded. With the program in the
computer’s memory, type:
SAVE "CHA R A C T E R S "
The computer responds with the prompt message:
P r e s s R E C a n d P L A Y t h e n a n y k e y :
Remember the qualification of the term ‘any key’, the tape will start and the computer will save the
program under the filename CHARACTERS
.
IMPORTANT
Note that the computer cannot detect whether or not you have actually pressed the correct cassette
keys - so if you only press [PLAY], the tape will start and the program will appear to be saved when
it is not.
BEWARE: If you accidentally press [REC] and [PLAY] when you want to read/load in a program
from tape, then you will erase whatever programs exist on the cassette. If uninterrupted by pressing
the [ESC] key, the tape will wind through to the end and be completely erased since the tape will not
have been halted by the computer finding the program it was searching for. If you are anxious to
avoid losing data in this way, get in to the habit of using the snap-off write protect tabs on the
cassette casing before you remind yourself the hard way.