Apple IIe - Page 175

Cassette and Disk Storage with the Apple lie 175
Illustration 5-3. Tracks and Sectors
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In Apple 's Disk II system , the diskette is divided into 35 different
tracks.
To further reduce the time necessary to search for a particular
data item , Apple's DOS* divides each track into 16 sectors (see
Illustration 5-3.)
Each sector can store up to 256 bytes of information . When the
Disk !l 's read / write head* is in place over a specific track, that
track's 16 sectors will pass one by one underneath the read / write
head as the diskette rotates.
Whenever DOS reads or writes information from the diskette , it
does so in groups of 256 bytes. In other words , data is read from
or written to the diskette one sector at a time .
*DOS stands for disk operating system which will be explained in
detail later.