15
keyboard
(except
the
numeric
keyboard)
and
one
key
restart
of
the
host
machine.
There
is
an
indicator
lamp
above
each
functional
button,
and
the
lamps
will
be
on
after
starting
up.
When
the
central
control
panel
is
in
the
lock
state,
the
above
indicator
lamp
is
on.
And
the
indicator
lamp
will
flicker
for
10
times
and
then
go
out
during
the
system
restarting.
1.4
Display
The
projector
control
includes
power
button,
save
power
button
and
signal
switch
button.
These
buttons
can
select
the
switch
on/off,
electrical
consumption,
signal
sources
of
the
projector
so
as
to
play
a
role
in
controlling
the
projector
and
replacing
the
functions
of
part
of
the
remote
control
button.
Airlink
：
A
key
to
support
Airlink
software
startup
and
shutdown
The
signal
switch
sequence
is
as
follows:
1.5
Volume
Control
The
volume
control
includes
three
buttons:
,
volume
‐
and
mute,
correspondingly
controlling
the
amplifier
of
the
centralized
control,
but
not
the
volume
of
the
host
machine.
The
centralized
control
has
increased
the
volume
of
the
host
machine
to
its
utmost
during
the
starting
up,
which
skips
the
process
of
manual
adjustment
of
the
host
machine
volume
and
makes
the
volume
control
more
reasonable.
As
for
the
volume
increase
and
decrease
of
the
player,
it
is
not
controlled
by
the
centralized
control,
but
by
hand.
What
it
should
be
highlighted
is
that
through
the
internal
USB
sound
card,
there
is
no
need
for
host
audio
output
wire
or
external
audio
enter
wire,
but
one
USB
wire
is
enough,
which
means
it
is
by
USB
wire
that
the
host
volume
and
external
volume
are
transferred
into
the
centralized
control.
Using
B
type
USB
enter
port
for
external
connection
saves
external
audio
wire
connection,
facilitating
the
operation.
The
default
starting
‐
up
volume
is
50%
of
the
starting
‐
up
volume;
in
mute
state,
we
can
cancel
mute
by
pressing
the
volume
increase
or
decrease
buttons
as
well
as
press
the
mute
button.
However
the
volume
after
mute
is
cancelled
is
different
by
different
ways
of
cancelling.
Mute
cancelling
method
Pressing
volume
increase
Pressing
volume
decrease
Pressing
mute
Volume
Volume
before
mute
+10.23dB
Volume
before
mute
‐
10.23dB
Volume
before
mute
1.6
USB
Extension
The
USB
extension
has
four
A
type
USB
2.0
interface
which
are
used
to
solve
the
short
supply
of
the
USB
interface.
Four
USB2.0
interface
can
be
connected
to
the
general
USB
devices
including:
USB
drive,
USB
mouse,
USB
keyboard,
mobile
hard
disc
drive,
etc.
The
USB
extension
interface
uses
MTT
(Multiple
Transaction
Translator)
architecture
for
the
standard
USB
extension
chips
so
that
the
USB
communication
speed
will
not
be
affected
by
increasing
another
USB
device.
Meanwhile,
with
a
strong
compatibility,
it
can
be
compatible
with
various
common
USB
devices.
1.7
External
connection