http://www.blackdown.org/~hwb/co_JoystickAtari7800.html (Amiga Plus Extra No. 5, 08/1997)

Atari 7800 Joystick

9 PIN D-SUB MALE (At the Atari)
9 PIN D-SUB FEMALE (At the joystick cable)

9 PIN D-SUB MALE at the Atari.
9 PIN D-SUB FEMALE at the joystick cable.

Pin	Color	Dir	Description
1	WHT		Up
2	BLU		Down
3	GRN		Left
4	BRN		Right
5	RED		Button (R)ight (-)
6	ORG	?	Both buttons (+)
7	n/c	-	Not connected
8	BLK		Ground(-)
9	YLW		Button (L)eft (-)

Note: Direction is Computer relative Joystick.
Note: Connect Direction and Button(L/R) to Ground for action. And Both Button to Button L and Button R for action.

Contributor: Joakim Ögren

Source: Classic Atari 2600/5200/7800 Game Systems FAQ

Please send any comments to Joakim Ögren.