AMSTRAD CPC464, Руководство пользователя

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There are four ways in which files may be SAVEd by the CPC464. You have just seen the most
general method, but there are three alternative formats for more specialised purposes.
2.6.2 SAVE "
<filename>” ,
A
The procedure is the same as above, except that the suffix ,A instructs the computer to save the
program or data in the form of an ASCII text file, rather than the shorthand notation the computer
uses by default.
This method of saving data applies to files created by wordprocessors and other applications
programs, and its use will be further discussed as applications are encountered.
2.6.3 SAVE "
<filename> ” ,
P
The , P tells the computer to protect (scramble) the data on the cassette so that the program cannot
easily be read by anyone RUNning it from cassette and then stopping its execution using the [ESC]
key function. Programs saved in this way can only be recalled using the RUN or CHAIN commands.
If you anticipate wanting to edit or alter the program, you should also keep a copy for yourself in
unprotected form.
2.6.4
SA V E " < f i l e n a m e > ” , B , < s t a r t a d d r e s s > , < l e n g t h > [ , < e n t r y
point>]
This option allows you to perform a binary save where a complete block of the data stored in the
computer’s RAM is stored onto the cassette exactly as it occurs in the internal memory. It is
necessary to instruct the computer where the section of memory you need to save starts, how long it
is, and the memory address at which to start execution if the file is to RUN as a program.
This binary save feature allows data from a screen display to be stored directly onto the cassette in
the form of a screen dump. One of it’s main uses is to build ‘title’ sequences for long programs
-
breaking the monotony of a lengthy loading process.
2.6.5
Unnamed files and CAT
If you SAVE a file without giving it a file name:
SAVE “”
then BASIC will save it as an Unnamed file. The cassette can save as many files of the same name
(including unnamed files) as can be fitted onto a tape one after another, unlike a disk system which
requires each entry to have a unique name.