Atari 400 User Manual

210 User's Ha ndb ook to the Atari 400/ 800 Comp uters
the various sectors is determined by co unting the numb er of
hol es occuring after the first sector. A hard sectored diskette is
depict ed in Illustrati on 7-4.
Soft sectored diskettes have
on ly one ind ex hole as shown in
Illu st ration 7-5. This so lit ary index hole marks the loca tion of the
fir st sec tor . By timin g the rot at ion speed of the fl oppy diskette,
the l ocation of the other sectors ca n be determ ined. The Atari
810 uses soft-sectored diskettes.
Illustration 7-4. Hard Sectored Diskette
2 Ind ex
Hol es
Sector

Atari 400 Specifications

General

Manufacturer	Atari
Model	400
Type	Home Computer
Release Year	1979
CPU	MOS Technology 6502
CPU Speed	1.79 MHz
ROM	10 KB
Operating System	Atari OS
Keyboard	Membrane keyboard
RAM	8 KB (expandable to 48 KB)
Graphics	ANTIC and GTIA chips
Sound	4 channels
Display	RF output for connection to TV
Storage	Optional cassette tape drive or floppy disk drive
Ports	Cartridge
Display Resolution	320x192 (16 colors)