Speaker interface
The
sound system has
a small,
permanent magnet,
2
1/4-inch
speaker.
The
speaker can
be driven
from
one
or
two
sources:
-
An
8255A-5 PPl output
bit.
The
address and the
bit
are
defined
in
the
l/O
address
map.
-
A
timer
clock
channel, the output
of
which is pro-
grammable
within
the functions
of
the
8253—5
timer
when using
a
1.19MHz clock input. The timer
gate
is
also
controlled
by
an 8255A-5 PPl output port
bit. Ad-
dress
and
bit
assignment are
in
the
l/O
address
map.
The
speaker
connector
is
a
two-pin
90—degree
con—
nector.
See
Speaker connector
section
for more
infor-
mation.
30
333
O
J
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