Commodore VIC-20 User Manual page 43

Protective jacket
Hard
I
soft-sectored hole
Write-protect notch;
when covered, diskette
contents cannot be altered
Chapter 1: Introducing the VIC 20 Computer
29
:1l0powwo:)
FIGURE
1·11.
Floppy diskette
As mentioned earlier, the 1540 disk drive puts more data onto a single
diskette than almost any other disk drive. The way it does this is by putting
more blocks of data (sectors) into the data tracks that are near the outside of
the diskette. Some disk drives put the same number of sectors on each track.
Of those that do this, there are some that use hard-sectored diskettes. These
diskettes have a series of evenly spaced holes near their center. The disk
drive uses these holes to position the sectors. Since the 1540 does not have
regularly spaced sectors, it does not use these holes. The 1540 uses only
soft-sectored diskettes (those with only one hole in them).
To determine what kind of diskette you have, follow this procedure (see
Figure 1-12):
1. Take the diskette out of its envelope (not the jacket), and hold it by
its edges.
2. Gently insert two fingers into the center hole.
3. Rotate the diskette with the two fingers in the center hole until a
small hole in the diskette aligns with the outer small hole in the
jacket.
4. Continue rotating the diskette inside the jacket. If you find only one
hole, the diskette is soft-sectored. If you find more than one hole it is
hard-sectored and cannot be used with the 1540 disk drive.