<s>
The	O
IBM	B-Device
AN/FSQ	I-Device
-31	I-Device
SAC	I-Device
Data	I-Device
Processing	I-Device
System	I-Device
(	O
FSQ-31	O
,	O
Q-31	O
,	O
colloq	O
.	O
)	O
</s>
<s>
was	O
a	O
USAF	O
command	O
,	O
control	O
,	O
and	O
coordination	O
system	O
for	O
the	O
Cold	B-Application
War	I-Application
Strategic	O
Air	O
Command	O
(	O
SAC	O
)	O
.	O
</s>
<s>
IBM	O
's	O
Federal	O
Systems	O
Division	O
was	O
the	O
prime	O
contractor	O
for	O
the	O
AN/FSQ	B-Device
-31s	I-Device
,	O
which	O
were	O
part	O
of	O
the	O
TBD	O
465L	O
SAC	O
Automated	O
Command	O
and	O
Control	O
System	O
(	O
SACCS	O
)	O
,	O
a	O
"	O
Big	O
L	O
"	O
system	O
of	O
systems	O
(	O
cf	O
.	O
</s>
<s>
</s>
<s>
IBM	O
4020	O
Military	O
Computer	O
with	O
Programming	B-General_Concept
and	I-General_Concept
Numerical	I-General_Concept
System	I-General_Concept
and	I-General_Concept
"	I-General_Concept
Arithmetic	I-General_Concept
Unit	I-General_Concept
including	I-General_Concept
storage	I-General_Concept
access	I-General_Concept
"	I-General_Concept
,	O
liquid-cooled	O
Ferrite	O
Core	O
storage	O
(	O
65,536	O
words	O
)	O
,	O
High-Speed	O
Input/Output	O
to	O
the	O
Drum	B-General_Concept
Memory	I-General_Concept
system	O
,	O
and	O
the	O
Low-Speed	O
Input/Output	O
section	O
to	O
interface	O
with	O
several	O
different	O
devices	O
:	O
</s>
<s>
IBM	B-Device
1401	I-Device
,	O
which	O
controlled	O
data	O
transfers	O
from	O
unit-record	O
equipment	O
:	O
</s>
<s>
Drum	B-General_Concept
memory	I-General_Concept
system	O
with	O
controller	O
and	O
two	O
vertical	O
drum	B-General_Concept
memory	I-General_Concept
devices	O
.	O
</s>
<s>
SACCS	O
systems	O
outside	O
of	O
the	O
AN/FSQ	B-Device
-31	I-Device
included	O
the	O
and	O
the	O
at	O
the	O
Offutt	O
command	O
center	O
(	O
the	O
backup	O
SCP	O
was	O
at	O
Barksdale	O
AFB	O
.	O
)	O
</s>
<s>
Also	O
considered	O
as	O
part	O
of	O
the	O
memory	O
subsystem	O
in	O
that	O
they	O
were	O
addressed	O
via	O
fixed	O
reserved	O
memory	O
addresses	O
,	O
were	O
four	O
48	O
position	O
switch	O
banks	O
,	O
in	O
which	O
a	O
short	O
program	O
could	O
be	O
inserted	O
,	O
and	O
a	O
plugboard	O
,	O
similar	O
to	O
the	O
one	O
used	O
in	O
IBM	O
unit	O
record	O
equipment	O
,	O
that	O
had	O
the	O
capacity	O
of	O
32	O
words	O
,	O
so	O
longer	O
bootstrap	B-Application
or	O
diagnostic	O
programs	O
could	O
be	O
installed	O
in	O
plug	O
panels	O
which	O
could	O
then	O
be	O
inserted	O
into	O
the	O
receptacle	O
and	O
used	O
.	O
</s>
<s>
This	O
served	O
as	O
a	O
primitive	O
ROM	B-Device
.	O
</s>
