Atari 400 Hardware Manual

Controller Port Pinout:
PIN
JOYSTICK
1
Forward
2
Back
3
Left
4
Right
5
6
Trigger Button
7
8
GND
9
* Write
** PORTA or PORTB
Male
(console)
Controllers
PADDLE (POT)
A(Left)Trigger
B(Right)Trigger
POT B(Right)
+5
GND
POTA (Left)
*** STICK 0, 1, 2 or 3
III. 24
Female
(connector)
HARDWARE
KEYBOARD REGISTERS
Top Row* Bit 0 or
4**
2nd
Row*
Bit
1 or
5**
3rd
Row* Bit 2 or
6**
Bottom
Row* Bit 3
or
7**
1st
Column POT 1,3,5,7
3rd
Column
TRIG0,1,2,3
+5
2nd Column
POT 0,2,4,6
OS
VARIABLES
Bit
0***
Bit
1***
PTRIG0,2,4,6
Bit 2***
PTRIG1,3,5,7
Bit 3***
PADDL1,3,5,7
STRIG0,1,2,3
~
PADPL0,2,4,6l

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)