Atari 400 Field Service Manual

A.
ATARI
Consumer Product
Service
Manager of
TehnicaJ Support
TECH
TIP
number
MOOEL;
Atari MO/800
Computers
DATE:
May
2S,
1982
SUBaECT:
Revision B,
Operating
System
ROMS.
DESCRIPTIONS
New
Atari WO/800
computers
contain
Revision B
ROMs
—
a refined
version
of
an
Operating
System
ROM,
which
has
a different
checksum
from
Revision
A ROMs.
When
repiacing
these
components,
do not
mix revision
leveia.
System
will
not operate
if Revision
A
is
paired with
Revision
B.
Parts:
Old ROMS:
Cai2W9A
and C0U599A
Rev
B ROMS:
C012W9B
and
C0U599B
Part
Locations
*00
Computer
System
-
Motherboard
location
A103
(C014599)
and
AlO*
(C012W9)
800 Computer
System
-
Personality
Board
Location
AW1.(C01*599)
and
A403
(C012'J99).
You
can
recognize
the
new
part in
this manner:
Top
is imprinted
with
a copyright
symbol
followed
by 1981
Atari.
TROUBLESHOOTING
AND
MAINTENANCE
PROCEDURESs
For
troubleshooting,
maintenance
and testing,
observe
warnings
and
cautions
stated
in
Atari
*00/8CO
Home
Computer
System
Service
Manual.
Before
a
component
or board
IS
added
to
or removed
from
the
system,
power
the
system down.
If
ROM
chips are
defective
or if
printer
overprints
(hiccups),
replace
ROM
chips.

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)