Canon Cat Reference Manual page 36

If
you try
to record
an
older version
of
the
text
on top
of
a
newer
version,
the
Cat
will
beep and do
nothing.
[EXPLAIN]
will
tell you that your text is
at
risk.
Breaking the Connection Between Backups
Do
the
following to
break the connection between
two
backup disks:
-Play
back the
first
disk,
then
record
it
again using
[DISK].
Remove the
disk from
the
drive.
-
Erase
the entire text
(or play
back a non-backup
disk).
-
Play back the backup disk, then
record
it
again
using
lDrsKl.
[DISK]
will
now
treat the disks
as
unrelated
and
not
allow
vou to
record the
text of one on the other.
Erasing Disks
The conlmand for erasing a disk is[USE FRONT]－
[SHI口
「
]―
[DISK],then press[ERASE].After erasing a disk you can
rccord on it with[DISK],or make it a backup with[sHIFT]―
[D:SK].
一
Youhavejustused[D:SK],and diSCOvered thatthe disk
in the drive is not blank.You arc still holding
[USE FRONT],and peeking atthe text.[USE FRONT]is
the only key you are holding.
― ―
While holding[USE FRONT],preSS and hold[SHIFT].
― ―
While holding both[USE FRONT]and[SH!曰
「 ],preSS
and releasc[ERASE].ThiS erases the disk in the drive.
Once the disk is erased, the
information
it
held
is gone
for
good.
Erasing
leaves the
disk
totally
blank,
just
as
it
was
when new. To
preserve
your
text, zse [DISK]
or
[SHIFT]-[DISKf
to record it
before
turning
the
Cat off.
UNDO and DISK
[UNDO]has nO effect on[D:SK].