Atari 400 Field Service Manual

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Figure 1-3.
MPU
Pin
Assignments
Alphgtnumenc
Television
Interface
Controller
The
primary
function
of the
Alphanumeric
Television
Interface
Controller
(ANTIC)
chip
is to fetch
data
from
memory,
independent
of the
processor,
for display
on the
video
screen.
Figure 1-4
is an
illustration
of ANTIC
Pin
Assignments.
ATARI
Home
Computers
1-8

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)