Atari ProSystem Owner's Manual page 13

Using the
7800
Pro-Line
Controllers
The ATARI 7800 ProSystem
In-
cludes
two
advanced
controllers
designed
for
comfortable
and
responsive
gameplay. These
con-
trollers
provide
eight directions
of
control. Their function
for
each
game
is
explained
in
the
manual
for
the
particular
game you
are
playing.
Plug the
controllers into the jacks
at
the front of the console. Use
the
left
jack
for one-player games;
use both
Jacks for
two-player
games. Each Jack
is
designed to
fit
The
controller
only
one way.
Be
sure the
connection
is
firm,
but
do
not try
to force
it
In.
Each
controller
has
two
fire
but-
tons.
For most games, the
right
and
left fire
buttons perform the
same
functions,
and you
can
use
whichever
is
most
comfortable.
For
more
realistic
play
in
some
games,
however,
these buttons
are
capable of
independent
func-
tions.
Consult
your game
manual
for instructions
on
how
to use the
controllers
and
fire
buttons
for
the
particular
game you
are
playing.