Atari 400 Hardware Manual

Shift
Register
CHBASE
l
I
I
r
I
Character Display
(20 Character per line mode example)
Codes (names)
Stored in
Shift Register
F
Color
Register
Select
I
not
.............
v
I
X
I
__ :; _ ____..
I
Address portion of
Character name
used
..,.....,
v
I
Character
Data Address
Character Set
in Memory
w
y
Addresses data in
character set
displays on the
Color assigned
by color register
selected
II .14
z
'\
I
Internal
codes for
characters
in memory
F
X
z
0
1 TV
2 Scan
3 Lines
4
5
6
7
/

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)