Table of Contents
Advertisement
How the Cat Knows What to Do
By
comparing the
text in memory
to the
disk in
the
drive,
the Cat
figures out
whether
to
record,
play
back, or beep.
It looks
at
whetherthe text
is
clean or
dirty,
and
whetherthe
text
came
from
the disk
in
the
drive or
some
other disk.
Charts presented later
in this
chapter on
page 32
illustrate
exactly what decisions the Cat
makes under
any and
all
circumstances.
Peeking at a Disk
That Doesn't Match
When
the
text in memory
does
notbelong
to the
disk in the
drive, recording
orplaying
back
might
lose
valuable
infor-
mation.
If
the Cat were
to
record the
text
in
memory,
it
would wipe
out
the
text
on the
disk. This would
be
fine
if
the
text in
the
memory
were
a
more up-to-date
version
of
the
text
on the
disk, but
it's
not;
the
text
and the
disk
don't
match.
Similarly,
if
the Cat played back the
disk
in
the
drive,
it
would
lose
the
text
in
memory.
But
that
would
cause
you to
lose
whatever
changes
you
had made
to
the
text
since
it
was last recorded.
When the
memory
and
the disk do not
match,
the
Cat
cannot
record
or
play back safely,
so
it gives you
a
warning
beep and does
neither.
However,
it
does
provide
a
helpful
peekatthetext
stored on the
disk in
the
drive
for
as
long
as
you hold
down
[USE
FRONT].
The text
that appears on
your
screen
while
you hold down
[USE FRONT]
is
the
text that
would
be
there
if
the Cat
did play back
the
disk
in the
drive.
When
you
release IUSE FRoNT],
the
screen
retums
to
normal.
The
[EXPLAIN] message
that
accompanies
the waming
beep
tells you how to record or play
back
without
losing
information.
There
may
be
a
pause
between
the
time
you
give
[DISK] and the
beep.
Write-Protected Disks
The Cat automatically checks
to
see
if
a
disk
is
write-
protected
before recording.
If
the
disk
is
write-protected,
the Cat beeps
and
does
nothing.
[EXPLAIN]
tells
you
that the
disk is write-protected.
Disks
From Other
Systems
If
the
disk
in
the
drive
is not
a Cat
disk but
does have
information
recorded
on
it,
the Cat
beeps
and does not
record or
play
back.
IEXPLAIN]
tells you
the
diskis
unrec-
ognized,
"or
not
a
Cat
disk."
Advertisement
Chapters
Table of Contents
