<s>
The	O
Fairchild	B-General_Concept
9440	I-General_Concept
MICROFLAME	O
,	O
also	O
known	O
as	O
the	O
F9440	O
and	O
μFLAME	O
,	O
was	O
a	O
16-bit	B-Device
microprocessor	B-Architecture
introduced	O
by	O
Fairchild	O
Semiconductor	O
in	O
1977	O
.	O
</s>
<s>
The	O
9440	O
implemented	O
the	O
Data	B-Device
General	I-Device
Nova	I-Device
2	I-Device
's	I-Device
instruction	B-General_Concept
set	I-General_Concept
in	O
a	O
single-chip	O
40-pin	O
DIP	B-Algorithm
.	O
</s>
<s>
By	O
this	O
time	O
the	O
16-bit	B-Device
designs	O
were	O
being	O
surpassed	O
by	O
32-bit	O
designs	O
and	O
hybrids	O
like	O
the	O
Motorola	B-Device
68000	I-Device
,	O
and	O
Fairchild	O
began	O
turning	O
their	O
attention	O
to	O
their	O
own	O
32-bit	O
Fairchild	B-General_Concept
Clipper	I-General_Concept
design	O
.	O
</s>
<s>
The	O
underlying	O
core	O
of	O
the	O
9445	O
was	O
also	O
used	O
to	O
implement	O
the	O
9450	O
,	O
which	O
used	O
new	O
microcode	B-Device
to	O
implement	O
the	O
MIL-STD-1750A	B-General_Concept
instruction	B-General_Concept
set	I-General_Concept
.	O
</s>
<s>
The	O
Data	B-Device
General	I-Device
Nova	I-Device
was	O
introduced	O
in	O
1969	O
,	O
implemented	O
using	O
individual	O
integrated	O
circuits	O
(	O
ICs	O
)	O
mounted	O
on	O
a	O
15x15-inch	O
printed	O
circuit	O
board	O
.	O
</s>
<s>
In	O
order	O
to	O
lower	O
design	O
complexity	O
,	O
and	O
thus	O
board	O
size	O
and	O
cost	O
,	O
the	O
arithmetic	B-General_Concept
logic	I-General_Concept
unit	I-General_Concept
(	O
ALU	O
)	O
was	O
only	O
4-bits	O
wide	O
,	O
implemented	O
using	O
a	O
single	O
74181	O
IC	O
.	O
</s>
<s>
This	O
meant	O
it	O
required	O
four	O
machine	O
cycles	O
to	O
complete	O
a	O
16-bit	B-Device
instruction	O
,	O
but	O
it	O
also	O
allowed	O
the	O
system	O
to	O
be	O
much	O
less	O
expensive	O
than	O
competing	O
minicomputers	B-Architecture
from	O
Digital	O
Equipment	O
Corporation	O
(	O
DEC	O
)	O
or	O
Hewlett-Packard	O
.	O
</s>
<s>
The	O
NOVA	O
was	O
very	O
successful	O
,	O
propelling	O
DG	O
into	O
the	O
second-place	O
position	O
behind	O
DEC	O
in	O
the	O
minicomputer	B-Architecture
market	O
during	O
the	O
1970s	O
.	O
</s>
<s>
In	O
1970	O
,	O
DG	O
introduced	O
the	O
SuperNOVA	O
,	O
which	O
featured	O
a	O
full	O
16-bit	B-Device
wide	O
ALU	O
using	O
four	O
74181	O
's	O
in	O
bit-slice	B-General_Concept
fashion	O
,	O
and	O
thus	O
ran	O
about	O
four	O
times	O
as	O
fast	O
as	O
the	O
original	O
NOVA	O
.	O
</s>
<s>
This	O
was	O
further	O
boosted	O
by	O
other	O
changes	O
,	O
including	O
faster	O
core	B-General_Concept
memory	I-General_Concept
and	O
optional	O
semiconductor	B-Architecture
memory	I-Architecture
,	O
making	O
the	O
SuperNOVA	O
the	O
fastest	O
mini	O
for	O
some	O
time	O
.	O
</s>
<s>
This	O
also	O
meant	O
there	O
were	O
two	O
different	O
central	B-General_Concept
processing	I-General_Concept
unit	I-General_Concept
designs	O
implementing	O
the	O
same	O
underlying	O
instruction	B-General_Concept
set	I-General_Concept
architecture	I-General_Concept
(	O
ISA	O
)	O
.	O
</s>
<s>
Improving	O
semiconductor	B-Architecture
fabrication	I-Architecture
processes	O
,	O
especially	O
through	O
the	O
1970s	O
,	O
put	O
increasing	O
pressure	O
on	O
the	O
individual-IC	O
CPU	O
designs	O
like	O
the	O
NOVA	O
.	O
</s>
<s>
Initially	O
,	O
only	O
4-bit	O
and	O
then	O
8-bit	O
CPUs	O
could	O
easily	O
be	O
manufactured	O
on	O
a	O
single	O
chip	O
,	O
but	O
by	O
the	O
mid-1970s	O
,	O
16-bit	B-Device
designs	O
were	O
appearing	O
.	O
</s>
<s>
In	O
1973	O
,	O
National	O
Semiconductor	O
introduced	O
the	O
IMP-16	B-Device
,	O
which	O
implemented	O
a	O
NOVA-like	O
system	O
in	O
a	O
set	O
of	O
only	O
five	O
IC	O
's	O
.	O
</s>
<s>
The	O
next	O
year	O
their	O
PACE	B-Device
reduced	O
that	O
to	O
a	O
single	O
IC	O
.	O
</s>
<s>
Several	O
similar	O
designs	O
appeared	O
during	O
this	O
period	O
,	O
including	O
the	O
Texas	O
Instruments	O
TMS	B-General_Concept
9900	I-General_Concept
,	O
which	O
implemented	O
their	O
TI-990	B-Device
minicomputer	B-Architecture
,	O
and	O
the	O
Intersil	B-General_Concept
6100	I-General_Concept
,	O
a	O
single-chip	O
version	O
of	O
the	O
PDP-8	B-Device
.	O
</s>
<s>
DG	O
needed	O
to	O
respond	O
to	O
these	O
systems	O
,	O
and	O
began	O
development	O
of	O
the	O
microNOVA	O
mN601	O
,	O
a	O
single-chip	O
design	O
that	O
implemented	O
the	O
NOVA	O
3	O
instruction	B-General_Concept
set	I-General_Concept
.	O
</s>
<s>
The	O
courts	O
had	O
already	O
decided	O
that	O
the	O
instruction	B-General_Concept
set	I-General_Concept
of	O
a	O
CPU	O
was	O
not	O
subject	O
to	O
copyright	O
,	O
and	O
this	O
had	O
been	O
tested	O
several	O
times	O
by	O
companies	O
that	O
implemented	O
IBM	O
mainframe	B-Architecture
compatible	O
systems	O
using	O
different	O
internal	O
implementations	O
.	O
</s>
<s>
DG	O
had	O
also	O
done	O
nothing	O
about	O
the	O
introduction	O
of	O
the	O
IMP-16	B-Device
and	O
PACE	B-Device
,	O
both	O
similar	O
to	O
DG	O
designs	O
.	O
</s>
<s>
Using	O
a	O
new	O
2-micron	O
process	O
,	O
the	O
9445	O
implemented	O
the	O
NOVA	O
3	O
instruction	B-General_Concept
set	I-General_Concept
in	O
microcode	B-Device
,	O
added	O
built-in	O
hardware	O
multiply	O
and	O
divide	O
,	O
and	O
added	O
addressing	O
for	O
up	O
to	O
128kWords	O
.	O
</s>
<s>
By	O
this	O
time	O
,	O
the	O
first	O
32-bit	O
microprocessors	B-Architecture
were	O
coming	O
to	O
market	O
,	O
and	O
all	O
of	O
the	O
Nova-based	O
machines	O
were	O
outdated	O
.	O
</s>
<s>
In	O
1986	O
,	O
with	O
the	O
minicomputer	B-Architecture
market	O
collapsing	O
as	O
newer	O
IBM	B-Device
PC	I-Device
designs	O
began	O
to	O
take	O
over	O
their	O
market	O
,	O
DG	O
decided	O
to	O
settle	O
.	O
</s>
<s>
This	O
version	O
was	O
fabbed	O
in	O
1.25μm	O
CMOS	B-Device
form	O
and	O
began	O
deliveries	O
in	O
1990	O
.	O
</s>
<s>
This	O
was	O
a	O
transistor	B-General_Concept
–	I-General_Concept
transistor	I-General_Concept
logic	I-General_Concept
(	O
TTL	B-General_Concept
)	O
system	O
,	O
so	O
the	O
resulting	O
chip	O
required	O
only	O
a	O
single	O
+5V	O
power	O
supply	O
instead	O
of	O
the	O
four-level	O
supply	O
of	O
the	O
mN601	O
.	O
</s>
<s>
It	O
shipped	O
in	O
the	O
same	O
40-pin	O
DIP	B-Algorithm
as	O
the	O
mN601	O
.	O
</s>
<s>
Internally	O
,	O
the	O
system	O
was	O
different	O
to	O
the	O
NOVA	O
2	O
;	O
as	O
the	O
data	O
sheet	O
put	O
it	O
,	O
"	O
Though	O
structurally	O
different	O
from	O
the	O
CPUs	O
of	O
the	O
Data	B-Device
General	I-Device
NOVA	I-Device
line	O
of	O
minicomputers	B-Architecture
,	O
the	O
9440	O
offers	O
comparable	O
performance	O
and	O
executes	O
the	O
same	O
instruction	O
set.	O
"	O
</s>
<s>
This	O
was	O
possible	O
because	O
the	O
instruction	B-General_Concept
set	I-General_Concept
was	O
in	O
microcode	B-Device
,	O
allowing	O
the	O
CPU	O
to	O
(	O
in	O
theory	O
)	O
be	O
of	O
any	O
design	O
at	O
all	O
.	O
</s>
<s>
The	O
μFLAME	O
differed	O
from	O
the	O
mN601	O
slightly	O
in	O
programming	O
model	O
,	O
as	O
its	O
instruction	B-General_Concept
set	I-General_Concept
was	O
based	O
on	O
the	O
NOVA	O
2	O
,	O
not	O
NOVA	O
3	O
,	O
and	O
thus	O
lacked	O
the	O
hardware	O
stack	B-General_Concept
that	O
had	O
been	O
introduced	O
on	O
the	O
3	O
.	O
</s>
<s>
While	O
the	O
9440	O
included	O
direct	B-General_Concept
memory	I-General_Concept
access	I-General_Concept
(	O
DMA	O
)	O
signals	O
to	O
indicate	O
the	O
start	O
and	O
end	O
of	O
a	O
DMA	O
process	O
,	O
when	O
it	O
received	O
them	O
it	O
simply	O
paused	O
and	O
released	O
the	O
system	O
bus	O
.	O
</s>
<s>
The	O
9445	O
fully	O
implemented	O
the	O
NOVA3	O
instruction	B-General_Concept
set	I-General_Concept
,	O
adding	O
the	O
SP	O
(	O
stack	B-General_Concept
pointer	O
)	O
and	O
FP	O
(	O
frame	O
pointer	O
)	O
registers	O
to	O
support	O
the	O
hardware	O
stack	B-General_Concept
.	O
</s>
<s>
It	O
added	O
the	O
hardware-based	O
16-bit	B-Device
multiply	O
and	O
divide	O
that	O
had	O
been	O
left	O
out	O
of	O
the	O
9440	O
,	O
eliminating	O
the	O
need	O
for	O
the	O
9443	O
.	O
</s>
<s>
On	O
top	O
,	O
it	O
added	O
a	O
suite	O
of	O
new	O
opcodes	B-Language
to	O
help	O
with	O
floating-point	B-Algorithm
math	I-Algorithm
,	O
which	O
could	O
operate	O
on	O
8-	O
,	O
16	O
-	O
or	O
32-bit	O
data	O
.	O
</s>
<s>
The	O
ALU	O
was	O
expanded	O
from	O
4-bits	O
to	O
a	O
full	O
16-bit	B-Device
implementation	O
,	O
greatly	O
improving	O
overall	O
performance	O
.	O
</s>
<s>
Fairchild	O
used	O
the	O
same	O
underlying	O
processor	O
design	O
of	O
the	O
9445	O
,	O
with	O
different	O
microcode	B-Device
,	O
to	O
produce	O
the	O
9450	O
.	O
</s>
<s>
This	O
provided	O
the	O
MIL-STD-1750A	B-General_Concept
instruction	B-General_Concept
set	I-General_Concept
instead	O
of	O
the	O
Nova	O
's	O
.	O
</s>
<s>
This	O
reached	O
the	O
market	O
in	O
1985	O
,	O
offering	O
a	O
built-in	O
math	O
processor	O
,	O
an	O
optional	O
external	O
chip	O
on	O
most	O
other	O
1750A	B-General_Concept
implementations	O
.	O
</s>
