Atari 800 User Manual

208 User's Handbook to the Atari 400/800 Computers
Floppy diskettes come in two sizes: 8 inch and 5114 inch. The 5114
inch diskettes are also known as mini-floppy diskettes. The Atari
810 Disk Driv e uses mini-floppy diskettes.
Tracks & Sectors
To facilitate the proc ess of searching for data on the diskette
surface, that surface is divided into tracks and sectors.
Tracks may be visualized
as a series of concentric circles on the
diskette surface, as shown in illustration 7-3. Atari's DOS divides
a
diskette into 40 tracks.
To
further reduce the time necessary to search for a particular
data item, Atari's DOS divides each track into 18 sectors, which
are also shown in illu st ration 7-3.
With 40 tracks available and 18 sectors per track, Atari DOS
divides each diskette into 720 sectors. However , 18 of these 720
sectors are used by Atari DOS , and cannot be used to store
programs
or data.
One
Sector of
Track
Illustration 7-3. Tracks and Sectors
~--' ......
.," ----' .....
" ..... ,'
// .... --- ..... ,
//,. ...... "' \
1/ // ,---... "
/
'
I /' " '
1/1 \\\\
"/' 0 \\\
"~: 'II'
'\' }'I'
\ \ I'll
\\ \' B / '/1
\ \ ,,'... ...../ // / /
,
'- ...... ./ / /
'" ...... - _ ..... .//
,,, ,..
...... '----,.../
....... --.-~
Track

Atari 800 Specifications

General

Processor	MOS Technology 6502
Processor Speed	1.79 MHz
ROM	10 KB
Graphics	ANTIC and GTIA chips
Release Year	1979
Display Resolution	up to 320 x 192
Colors	128 colors
Sound	4 channels
Storage	Cartridge, cassette, floppy disk
Ports	Cartridge, serial, monitor
Operating System	Atari OS