<s>
The	O
Honeywell	B-Device
Level	I-Device
6	I-Device
was	O
a	O
line	O
of	O
16-bit	B-Device
minicomputers	B-Architecture
,	O
later	O
upgraded	O
to	O
32-bit	O
,	O
manufactured	O
by	O
Honeywell	O
,	O
Inc	O
.	O
from	O
the	O
mid	O
1970s	O
.	O
</s>
<s>
In	O
1979	O
the	O
Level	O
6	O
was	O
renamed	O
the	O
DPS	B-Device
6	I-Device
,	O
subsequently	O
DPS	B-Device
6	I-Device
Plus	O
and	O
finally	O
DPS	O
6000	O
.	O
</s>
<s>
The	O
CPU	O
featured	O
a	O
real-time	O
clock	O
,	O
a	O
ROM	B-Device
bootstrap	B-Operating_System
loader	I-Operating_System
and	O
64	O
interrupt	B-Operating_System
levels	I-Operating_System
.	O
</s>
<s>
The	O
architecture	O
provided	O
a	O
variety	O
of	O
addressing	B-Language
modes	I-Language
and	O
18	O
programmer-visible	O
registers	B-General_Concept
.	O
</s>
<s>
Rack-mount	B-Application
and	O
tabletop	O
versions	O
were	O
available	O
.	O
</s>
<s>
All	O
three	O
models	O
all	O
featured	O
the	O
Megabus	O
,	O
which	O
was	O
a	O
proprietary	O
asynchronous	B-General_Concept
bus	I-General_Concept
architecture	O
.	O
</s>
<s>
The	O
other	O
four	O
models	O
supported	O
up	O
to	O
1MW	O
(	O
Mega	O
Words	O
)	O
of	O
memory	O
and	O
26	O
registers	B-General_Concept
.	O
</s>
<s>
A	O
memory	B-General_Concept
management	I-General_Concept
unit	I-General_Concept
(	O
MMU	O
)	O
,	O
optional	O
on	O
the	O
6/43	O
and	O
6/47	O
,	O
and	O
standard	O
on	O
the	O
6/53	O
and	O
6/57	O
,	O
supported	O
memory	B-General_Concept
segmentation	I-General_Concept
and	O
four	O
protection	B-Operating_System
rings	I-Operating_System
.	O
</s>
<s>
An	O
optional	O
Scientific	O
Instruction	O
Processor	O
(	O
SIP	O
)	O
added	O
single	O
-	O
and	O
double-precision	O
hardware	O
floating-point	B-Algorithm
instructions	O
.	O
</s>
<s>
The	O
6/47	O
and	O
6/57	O
were	O
enhanced	O
versions	O
of	O
the	O
6/43	O
and	O
6/53	O
respectively	O
which	O
added	O
a	O
Commercial	O
Instruction	O
Processor	O
(	O
CIP	O
)	O
including	O
30	O
additional	O
instructions	O
for	O
character-string	O
manipulation	O
and	O
decimal	B-Algorithm
arithmetic	O
.	O
</s>
<s>
In	O
the	O
1980s	O
,	O
Honeywell	O
's	O
Datanet	O
8	O
line	O
of	O
communications	O
processors	O
,	O
often	O
used	O
as	O
front-end	O
processors	O
for	O
DPS	O
8	O
mainframes	O
,	O
shared	O
many	O
hardware	O
components	O
with	O
DPS	B-Device
6	I-Device
.	O
</s>
<s>
In	O
June	O
1986	O
,	O
following	O
Honeywell	O
Information	O
Systems	O
 '	O
merger	O
with	O
Bull	O
,	O
Honeywell	O
Bull	O
introduced	O
the	O
DPS	B-Device
6	I-Device
Plus	O
line	O
of	O
symmetric	B-Operating_System
multiprocessing	I-Operating_System
32-bit	O
systems	O
,	O
models	O
410	O
and	O
420	O
(	O
code	O
named	O
MRX	O
-	O
Medium	O
Range	O
eXtended	O
)	O
with	O
up	O
to	O
four	O
processors	O
.	O
</s>
<s>
In	O
1987	O
they	O
introduced	O
the	O
uniprocessor	B-Operating_System
models	O
210	O
and	O
220	O
(	O
code	O
named	O
LRX	O
-	O
Low	O
Range	O
eXtended	O
)	O
,	O
announced	O
the	O
HRX	O
(	O
High	O
Range	O
eXtended	O
)	O
,	O
and	O
Computerworld	O
reported	O
that	O
there	O
were	O
more	O
than	O
50,000	O
DPS	B-Device
6	I-Device
systems	O
installed	O
worldwide	O
.	O
</s>
<s>
Recognising	O
the	O
commercial	O
success	O
of	O
Unix	O
,	O
in	O
1988	O
Honeywell	O
Bull	O
introduced	O
an	O
80386-based	O
Unix	O
co-processor	O
for	O
the	O
DPS	B-Device
6	I-Device
Plus	O
400	O
series	O
.	O
</s>
<s>
The	O
operating	B-General_Concept
system	I-General_Concept
for	O
the	O
Level	O
6	O
was	O
GCOS	B-Application
6	O
.	O
</s>
<s>
GCOS	B-Application
6	O
Mod	O
200	O
was	O
an	O
entry	O
version	O
of	O
the	O
system	O
oriented	O
toward	O
interactive	O
data	O
entry	O
.	O
</s>
<s>
GCOS	B-Application
6	O
Mod	O
400	O
was	O
a	O
batch	O
operating	B-General_Concept
system	I-General_Concept
also	O
used	O
to	O
run	O
process-control	O
applications	O
.	O
</s>
<s>
GCOS	B-Application
6	O
Mod	O
600	O
was	O
a	O
time-sharing	O
operating	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
The	O
DPS	B-Device
6	I-Device
Plus	O
line	O
ran	O
HVS	O
6	O
Plus	O
.	O
</s>
