<s>
In	O
the	O
theory	O
of	O
computation	O
,	O
a	O
Moore	B-General_Concept
machine	I-General_Concept
is	O
a	O
finite-state	B-Architecture
machine	I-Architecture
whose	O
current	O
output	O
values	O
are	O
determined	O
only	O
by	O
its	O
current	O
state	B-Application
.	O
</s>
<s>
This	O
is	O
in	O
contrast	O
to	O
a	O
Mealy	B-General_Concept
machine	I-General_Concept
,	O
whose	O
output	O
values	O
are	O
determined	O
both	O
by	O
its	O
current	O
state	B-Application
and	O
by	O
the	O
values	O
of	O
its	O
inputs	O
.	O
</s>
<s>
Like	O
other	O
finite	B-Architecture
state	I-Architecture
machines	I-Architecture
,	O
in	O
Moore	B-General_Concept
machines	I-General_Concept
,	O
the	O
input	O
typically	O
.	O
</s>
<s>
A	O
Moore	B-General_Concept
machine	I-General_Concept
can	O
be	O
defined	O
as	O
a	O
6-tuple	O
consisting	O
of	O
the	O
following	O
:	O
</s>
<s>
A	O
Moore	B-General_Concept
machine	I-General_Concept
can	O
be	O
regarded	O
as	O
a	O
restricted	O
type	O
of	O
finite-state	B-Architecture
transducer	I-Architecture
.	O
</s>
<s>
A	O
state	B-Application
transition	I-Application
table	I-Application
is	O
a	O
table	O
listing	O
all	O
the	O
triples	O
in	O
the	O
transition	O
relation	O
.	O
</s>
<s>
The	O
state	B-Application
diagram	I-Application
for	O
a	O
Moore	B-General_Concept
machine	I-General_Concept
,	O
or	O
Moore	O
diagram	O
,	O
is	O
a	O
diagram	O
state	B-Application
diagram	I-Application
that	O
associates	O
an	O
output	O
value	O
with	O
each	O
state	B-Application
.	O
</s>
<s>
As	O
Moore	O
and	O
Mealy	B-General_Concept
machines	I-General_Concept
are	O
both	O
types	O
of	O
finite-state	B-Architecture
machines	I-Architecture
,	O
they	O
are	O
equally	O
expressive	O
:	O
either	O
type	O
can	O
be	O
used	O
to	O
parse	O
a	O
regular	B-General_Concept
language	I-General_Concept
.	O
</s>
<s>
The	O
difference	O
between	O
Moore	B-General_Concept
machines	I-General_Concept
and	O
Mealy	B-General_Concept
machines	I-General_Concept
is	O
that	O
in	O
the	O
latter	O
,	O
the	O
output	O
of	O
a	O
transition	O
is	O
determined	O
by	O
the	O
combination	O
of	O
current	O
state	B-Application
and	O
current	O
input	O
(	O
as	O
the	O
domain	O
of	O
)	O
,	O
as	O
opposed	O
to	O
just	O
the	O
current	O
state	B-Application
(	O
as	O
the	O
domain	O
of	O
)	O
.	O
</s>
<s>
When	O
represented	O
as	O
a	O
state	B-Application
diagram	I-Application
,	O
</s>
<s>
for	O
a	O
Moore	B-General_Concept
machine	I-General_Concept
,	O
each	O
node	O
(	O
state	B-Application
)	O
is	O
labeled	O
with	O
an	O
output	O
value	O
;	O
</s>
<s>
for	O
a	O
Mealy	B-General_Concept
machine	I-General_Concept
,	O
each	O
arc	O
(	O
transition	O
)	O
is	O
labeled	O
with	O
an	O
output	O
value	O
.	O
</s>
<s>
Every	O
Moore	B-General_Concept
machine	I-General_Concept
is	O
equivalent	O
to	O
the	O
Mealy	B-General_Concept
machine	I-General_Concept
with	O
the	O
same	O
states	B-Application
and	O
transitions	O
and	O
the	O
output	O
function	O
,	O
which	O
takes	O
each	O
state-input	O
pair	O
and	O
yields	O
,	O
where	O
is	O
'	O
s	O
output	O
function	O
and	O
is	O
'	O
s	O
transition	O
function	O
.	O
</s>
<s>
However	O
,	O
not	O
every	O
Mealy	B-General_Concept
machine	I-General_Concept
can	O
be	O
converted	O
to	O
an	O
equivalent	O
Moore	B-General_Concept
machine	I-General_Concept
.	O
</s>
<s>
Some	O
can	O
be	O
converted	O
only	O
to	O
an	O
almost	O
equivalent	O
Moore	B-General_Concept
machine	I-General_Concept
,	O
with	O
outputs	O
shifted	O
in	O
time	O
.	O
</s>
<s>
This	O
is	O
due	O
to	O
the	O
way	O
that	O
state	B-Application
labels	O
are	O
paired	O
with	O
transition	O
labels	O
to	O
form	O
the	O
input/output	O
pairs	O
.	O
</s>
<s>
Consider	O
a	O
transition	O
from	O
state	B-Application
to	O
state	B-Application
.	O
</s>
<s>
The	O
output	O
corresponding	O
to	O
that	O
input	O
,	O
is	O
the	O
label	O
of	O
state	B-Application
.	O
</s>
<s>
Notice	O
that	O
this	O
is	O
the	O
source	O
state	B-Application
of	O
the	O
transition	O
.	O
</s>
<s>
So	O
for	O
each	O
input	O
,	O
the	O
output	O
is	O
already	O
fixed	O
before	O
the	O
input	O
is	O
received	O
,	O
and	O
depends	O
solely	O
on	O
the	O
present	O
state	B-Application
.	O
</s>
<s>
It	O
is	O
a	O
common	O
mistake	O
to	O
use	O
the	O
label	O
of	O
state	B-Application
as	O
output	O
for	O
the	O
transition	O
.	O
</s>
<s>
Simple	O
Moore	B-General_Concept
machines	I-General_Concept
have	O
one	O
input	O
and	O
one	O
output	O
:	O
</s>
<s>
Clocked	O
sequential	O
systems	O
are	O
a	O
restricted	O
form	O
of	O
Moore	B-General_Concept
machine	I-General_Concept
where	O
the	O
state	B-Application
changes	O
only	O
when	O
the	O
global	O
clock	O
signal	O
changes	O
.	O
</s>
<s>
Typically	O
the	O
current	O
state	B-Application
is	O
stored	O
in	O
flip-flops	B-General_Concept
,	O
and	O
a	O
global	O
clock	O
signal	O
is	O
connected	O
to	O
the	O
"	O
clock	O
"	O
input	O
of	O
the	O
flip-flops	B-General_Concept
.	O
</s>
<s>
A	O
typical	O
electronic	O
Moore	B-General_Concept
machine	I-General_Concept
includes	O
a	O
combinational	O
logic	O
chain	O
to	O
decode	O
the	O
current	O
state	B-Application
into	O
the	O
outputs	O
(	O
lambda	O
)	O
.	O
</s>
<s>
The	O
instant	O
the	O
current	O
state	B-Application
changes	O
,	O
those	O
changes	O
ripple	O
through	O
that	O
chain	O
,	O
and	O
almost	O
instantaneously	O
the	O
output	O
gets	O
updated	O
.	O
</s>
<s>
There	O
are	O
design	O
techniques	O
to	O
ensure	O
that	O
no	O
glitches	B-Error_Name
occur	O
on	O
the	O
outputs	O
during	O
that	O
brief	O
period	O
while	O
those	O
changes	O
are	O
rippling	O
through	O
the	O
chain	O
,	O
but	O
most	O
systems	O
are	O
designed	O
so	O
that	O
glitches	B-Error_Name
during	O
that	O
brief	O
transition	O
time	O
are	O
ignored	O
or	O
are	O
irrelevant	O
.	O
</s>
<s>
The	O
outputs	O
then	O
stay	O
the	O
same	O
indefinitely	O
(	O
LEDs	O
stay	O
bright	O
,	O
power	O
stays	O
connected	O
to	O
the	O
motors	O
,	O
solenoids	B-Algorithm
stay	O
energized	O
,	O
etc	O
.	O
</s>
<s>
)	O
,	O
until	O
the	O
Moore	B-General_Concept
machine	I-General_Concept
changes	O
state	B-Application
again	O
.	O
</s>
<s>
A	O
Moore	B-General_Concept
machine	I-General_Concept
with	O
nine	O
states	B-Application
for	O
the	O
above	O
description	O
is	O
shown	O
on	O
the	O
right	O
.	O
</s>
<s>
The	O
initial	O
state	B-Application
is	O
state	B-Application
A	O
,	O
and	O
the	O
final	O
state	B-Application
is	O
state	B-Application
I	O
.	O
</s>
<s>
The	O
state	B-Application
table	I-Application
for	O
this	O
example	O
is	O
as	O
follows	O
:	O
</s>
<s>
More	O
complex	O
Moore	B-General_Concept
machines	I-General_Concept
can	O
have	O
multiple	O
inputs	O
as	O
well	O
as	O
multiple	O
outputs	O
.	O
</s>
<s>
In	O
Moore	O
's	O
1956	O
paper	O
"	O
Gedanken-experiments	O
on	O
Sequential	O
Machines	O
"	O
,	O
the	O
automata	O
(	O
or	O
machines	O
)	O
are	O
defined	O
as	O
having	O
states	B-Application
,	O
input	O
symbols	O
and	O
output	O
symbols	O
.	O
</s>
<s>
Later	O
,	O
"	O
machines	O
"	O
became	O
known	O
as	O
"	O
Moore	B-General_Concept
machines	I-General_Concept
"	O
.	O
</s>
<s>
Given	O
an	O
arbitrary	O
machine	O
,	O
such	O
that	O
every	O
two	O
of	O
its	O
states	B-Application
are	O
distinguishable	O
from	O
one	O
another	O
,	O
then	O
there	O
exists	O
an	O
experiment	O
of	O
length	O
which	O
determines	O
the	O
state	B-Application
of	O
at	O
the	O
end	O
of	O
the	O
experiment	O
.	O
</s>
<s>
If	O
is	O
an	O
machine	O
,	O
such	O
that	O
every	O
two	O
of	O
its	O
states	B-Application
are	O
distinguishable	O
from	O
one	O
another	O
,	O
then	O
there	O
exists	O
a	O
branched	O
experiment	O
of	O
length	O
at	O
most	O
through	O
which	O
one	O
may	O
determine	O
the	O
state	B-Application
of	O
at	O
the	O
end	O
of	O
the	O
experiment	O
.	O
</s>
<s>
There	O
exists	O
an	O
machine	O
,	O
every	O
two	O
states	B-Application
of	O
which	O
are	O
distinguishable	O
from	O
one	O
another	O
,	O
such	O
that	O
the	O
length	O
of	O
the	O
shortest	O
experiments	O
establishing	O
the	O
state	B-Application
of	O
the	O
machine	O
at	O
the	O
end	O
of	O
the	O
experiment	O
is	O
equal	O
to	O
.	O
</s>
<s>
A	O
.	O
Karatsuba	O
,	O
"	O
On	O
a	O
problem	O
from	O
the	O
automata	O
theory	O
"	O
,	O
which	O
was	O
distinguished	O
by	O
testimonial	O
reference	O
at	O
the	O
competition	O
of	O
student	O
works	O
of	O
the	O
faculty	O
of	O
mechanics	O
and	O
mathematics	O
of	O
Moscow	O
State	B-Application
University	O
in	O
1958	O
.	O
</s>
