MC
‐
BUS
OPERATION
©
Cyrus
Audio
Ltd
Jun
2014
19
Cyrus
6
DAC,
Cyrus
8
DAC
service
manual
Issue
1
MC
‐
BUS
MC
‐
BUS
is
a
system
which
provides
communication
between
the
control
systems
of
a
number
of
Cyrus
products.
The
communication
takes
the
form
of
a
serial
data
stream
which
is
sent
from
a
'master'
product
and
received
and
repeated
by
'slave'
products.
The
data
is
thus
passed
from
one
product
to
another
around
a
loop.
The
master
product
should
then
receive
the
message
back
which
confirms
that
loop
connections
have
been
correctly
made.
Cyrus
amplifiers
are
'master'
products
and
send
commands
following
certain
key
sequences.
Products
such
as
CD
players
and
tuners
are
'slaves'
and
only
listen
to
MC
‐
BUS
for
commands
which
may
be
appropriate.
MC
‐
BUS
system
test
The
MC
‐
BUS
system
can
be
tested
by
substituting
the
amplifier
into
a
known
working
Cyrus
system
with
a
CD
player
or
tuner.
Note
that
MC
‐
BUS
must
be
connected
as
a
closed
loop.
It
is
also
important
to
connect
the
audio
signal
cables
between
components
to
provide
an
adequate
ground
return
path
for
the
MC
‐
BUS
signals.
Switch
on
the
power
to
the
system
and
set
all
components
to
Standby.
Selecting
an
input
on
the
amplifier
will
now
activate
both
the
amplifier
and
the
selected
device
(tuner
or
CD
as
connected).
When
the
amplifier
is
set
to
Standby,
all
other
components
connected
to
the
MC
‐
BUS
loop
will
also
set
to
Standby.
MC
‐
BUS
out
MC
‐
BUS
out
MC
‐
BUS
in
MC
‐
BUS
in
Amplifier
Tuner,
CD
player
etc.
