RANA Systems Elite Controller, Руководство пользователя

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ELITE SERIES USER MANUAL APPEN. A - DISK I/O
A P P E N D I X A
A . D I S K E T T E D A T A R E C O R D I N G
A . 1 . I n t r o d u c t i o n
This appendix is designed to show in detail how
information is structured on a diskette, begin-
ning with a brief introduction to the hardware
involved.
A . 2 . T r a c k s a n d S e c t o r s
Diskettes are divided into tracks and sectors
during the initialization process. Each track is
identified by its distance from the center of
the disk but, unlike the grooves of a record,
they are not connected in a continuous spiral. A
disk is similar to a record in that it is spun
at a constant speed and information is written
to or read from its surface with a read/write
head. Apple formats its diskettes into 35
tracks, numbered 0 to 34 with track 0 on the
outside and track 34 being the innermost.
The Elite One is capable of reading and writing
40 tracks (0 to 39). These five extra tracks
are located closer to the center of the disk
after Apple’s last track (34)
The dual headed Elite Two and Elite Three drives
require that the term “cylinder” be introduced.
Since the two heads allow the Elite Two and
Elite Three to read and write on both sides of
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