Hardware Reference
In-Depth Information
Because the shutter is not necessary for the disk to work, you can remove it from the
plastic case ifit becomes bent ordamaged. Pryit offthe diskcase; it popsoffwith asnap.
You also should remove the spring that pushes it closed. Additionally, after removing the
damaged shutter, you should copy the data from the damaged disk to a new one.
Rather than an index hole in the disk, the 3 1/2-inch disks use a metal center hub with
an alignment hole. The drive “grasps” the metal hub, and the hole in the hub enables the
drive to position the disk properly.
On the lower-left part of the disk is a hole with a plastic slider—the write-protect/enable
hole.Whenthesliderispositionedsotheholeisvisible,thediskis
write-protected
,mean-
ing the drive is prevented from recording on the disk. When the slider is positioned to
cover the hole, writing is enabled, and you can save data to the disk. For more perman-
ent write-protection, some commercial software programs are supplied on disks with the
slider removed so you can't easily enable recording on the disk. This is exactly opposite
of a 5 1/4-inch floppy, in which covered means write-protected, not write-enabled.
On the other (right) side of the disk from the write-protect hole is usually another hole
called the
media-density-selector
hole. If this hole is present, the disk is constructed of a
special medium and is therefore an HD or ED disk. If the media-sensor hole is exactly
opposite the write-protect hole, it indicates a 1.44MB HD disk. If the media-sensor hole
is located more toward the top of the disk (the metal shutter is at the top of the disk), it
indicatesa2.88MBEDdisk.Noholeontherightsidemeansthatthediskisalow-density
disk. Most 3 1/2-inch drives have a media sensor that controls recording capability based
on the absence or presence of these holes.
