<s>
The	O
ICL	B-Device
DRS	I-Device
was	O
a	O
range	O
of	O
departmental	O
computers	O
from	O
International	O
Computers	O
Limited	O
(	O
ICL	O
)	O
.	O
</s>
<s>
Standing	O
originally	O
for	O
Distributed	B-Device
Resource	I-Device
System	I-Device
,	O
the	O
full	O
name	O
was	O
later	O
dropped	O
in	O
favour	O
of	O
the	O
abbreviation	O
.	O
</s>
<s>
During	O
the	O
mid-1980s	O
separate	O
Office	O
Systems	O
business	O
units	O
had	O
produced	O
a	O
disparate	O
range	O
of	O
products	O
including	O
IBM-compatible	O
PCs	O
such	O
as	O
the	O
PWS	O
(	O
a	O
PC/AT	B-Operating_System
clone	O
)	O
,	O
small	O
servers	O
branded	O
DRS	O
,	O
and	O
various	O
larger	O
Unix	B-Application
servers	O
sold	O
under	O
the	O
Clan	O
range	O
.	O
</s>
<s>
The	O
basic	O
'	O
intelligent	O
terminal	O
 '	O
(	O
model10/110/210	O
)	O
used	O
8-bit	O
8085	B-General_Concept
processors	O
(	O
workstation	O
,	O
application	O
and	O
network	O
processors	O
)	O
,	O
each	O
with	O
between	O
32KB	O
and	O
128KB	O
of	O
memory	O
.	O
</s>
<s>
The	O
Model	O
210	O
also	O
had	O
an	O
80188	B-Device
application	O
processor	O
with	O
512KB	O
to	O
run	O
CP/M	B-Application
.	O
</s>
<s>
It	O
had	O
10KB	O
available	O
for	O
applications	O
programs	O
developed	O
in	O
CIS	O
COBOL	B-Application
.	O
</s>
<s>
The	O
final	O
model310	O
(	O
styled	O
like	O
a	O
DRS300	O
module	O
)	O
had	O
a	O
second	O
80186	B-Device
application	O
processor	O
with	O
1MB	O
RAM	O
to	O
run	O
Concurrent	B-Operating_System
DOS	I-Operating_System
,	O
emulating	O
an	O
IBMPC	B-Device
with	O
a	O
Hercules	B-Device
screen	O
display	O
.	O
</s>
<s>
were	O
connected	O
by	O
SCSI	B-Architecture
.	O
</s>
<s>
Initial	O
models	O
used	O
a	O
6MHz	O
80286	B-General_Concept
processor	O
(	O
A1	O
module	O
)	O
with	O
up	O
to	O
1MB	O
memory	O
.	O
</s>
<s>
Later	O
modules	O
used	O
an	O
8MHz	O
processor	O
(	O
A2	O
)	O
or	O
80286	B-General_Concept
with	O
80287	O
maths	B-General_Concept
coprocessor	I-General_Concept
(	O
A3	O
)	O
with	O
up	O
to	O
4MB	O
,	O
and	O
ran	O
Concurrent	B-Operating_System
CP/M	I-Operating_System
-86	I-Operating_System
and	O
later	O
Concurrent	B-Operating_System
DOS	I-Operating_System
.	O
</s>
<s>
Although	O
this	O
could	O
run	O
code	O
developed	O
under	O
CP/M	B-Application
,	O
PC	B-Operating_System
DOS	I-Operating_System
or	O
MS-DOS	B-Application
,	O
in	O
practice	O
available	O
applications	O
were	O
limited	O
because	O
many	O
shrink-wrapped	O
packages	O
developed	O
for	O
the	O
IBM	B-Device
PC	I-Device
made	O
use	O
of	O
direct	O
access	O
to	O
the	O
(	O
IBM	O
)	O
hardware	O
.	O
</s>
<s>
The	O
initial	O
DRS300	O
also	O
ran	O
ICL	O
's	O
implementation	O
of	O
Unix	B-Application
System	I-Application
V	O
Release	O
2	O
,	O
DRS/NXV2	O
,	O
though	O
that	O
was	O
never	O
released	O
commercially	O
.	O
</s>
<s>
Later	O
an	O
80386	B-General_Concept
(	O
A4	O
)	O
module	O
was	O
added	O
,	O
to	O
run	O
a	O
32-bit	O
DRS/NXV3	O
,	O
based	O
on	O
SystemV	O
Release3	O
.	O
</s>
<s>
These	O
brand	O
names	O
were	O
applied	O
to	O
bought-in	O
Unix	B-Application
boxes	I-Application
.	O
</s>
<s>
The	O
DRS400	O
originated	O
as	O
the	O
Clan4	O
,	O
based	O
on	O
the	O
Motorola	B-Device
68020	I-Device
running	O
UniSoft	B-Operating_System
's	O
Uniplus	B-Operating_System
Unix	B-Application
.	O
</s>
<s>
This	O
was	O
later	O
replaced	O
by	O
the	O
DRS400E	O
,	O
based	O
on	O
the	O
Motorola	B-Device
68030	I-Device
running	O
DRS/NXV3	O
.	O
</s>
<s>
The	O
successor	O
to	O
DRS300	O
,	O
the	O
DRS3000	O
was	O
an	O
IBM-compatible	O
,	O
80486-based	O
,	O
floor-standing	O
model	O
running	O
SVR4	O
.	O
</s>
<s>
The	O
P5	B-General_Concept
Pentium-based	O
Level	O
656	O
was	O
launched	O
in	O
September1993	O
.	O
</s>
<s>
The	O
in-house	O
(	O
Irvine/Bracknell	O
)	O
developed	O
DRS6000	O
was	O
launched	O
in	O
January1990	O
as	O
a	O
washing	O
machine-sized	O
SPARC-based	O
server	O
,	O
running	O
ICL	O
's	O
implementation	O
of	O
Unix	B-Application
SystemV	O
Release4	O
(	O
SVR4	O
)	O
.	O
</s>
<s>
It	O
also	O
had	O
a	O
68020-based	O
Central	O
Service	O
Module	O
board	O
(	O
CSM	O
)	O
,	O
leading	O
to	O
sarcastic	O
comments	O
in	O
the	O
press	O
that	O
it	O
was	O
a	O
DRS400	O
in	O
disguise	O
.	O
</s>
<s>
The	O
DRS6000	O
competed	O
directly	O
with	O
IBM	O
's	O
RS/6000	B-Device
,	O
which	O
was	O
launched	O
a	O
few	O
weeks	O
later	O
;	O
originally	O
planned	O
to	O
be	O
called	O
the	O
DRS600	O
it	O
was	O
renamed	O
when	O
it	O
was	O
found	O
that	O
IBM	O
had	O
decided	O
on	O
the	O
RS	O
6000	O
.	O
</s>
<s>
In	O
1994	O
,	O
the	O
DRS	O
range	O
was	O
superseded	O
by	O
the	O
SuperServer	O
(	O
Ks	O
(	O
SPARC	B-Architecture
)	O
and	O
Ki	O
(	O
Intel	O
)	O
)	O
and	O
TeamServer	O
(	O
Es	O
(	O
1-2	O
SPARC	B-Architecture
CPUs	O
)	O
,	O
Hs	O
(	O
2-4	O
SPARC	B-Architecture
CPUs	O
)	O
,	O
Ei	O
(	O
1	O
x86	B-Operating_System
CPU	O
)	O
,	O
Hi	O
(	O
2	O
x86	B-Operating_System
CPUs	O
)	O
)	O
ranges	O
of	O
SPARC	B-Architecture
and	O
Intel-based	O
machines	O
,	O
running	O
DRS/NX	O
Unix	B-Application
or	O
Microsoft	O
WindowsNT	O
.	O
</s>
<s>
In	O
1987	O
,	O
the	O
DRS	O
Professional	O
Work	O
Station	O
(	O
PWS	O
)	O
was	O
ICL	O
's	O
first	O
foray	O
into	O
IBM	B-Operating_System
PC/AT	I-Operating_System
compatible	O
computing	O
.	O
</s>
<s>
The	O
DRS	O
PWS	O
was	O
initially	O
released	O
with	O
MS-DOS	B-Application
4.0	I-Application
(	O
not	O
to	O
be	O
confused	O
with	O
the	O
later	O
public	O
releases	O
of	O
IBM	B-Operating_System
DOS	I-Operating_System
4.0	O
in	O
July	O
1988	O
and	O
MS-DOS	O
4.01	O
in	O
November	O
1988	O
)	O
.	O
</s>
<s>
This	O
was	O
a	O
real-mode	O
pre-emptive	O
multitasking	O
version	O
of	O
MS-DOS	B-Application
2.0	O
and	O
was	O
also	O
the	O
forerunner	O
of	O
OS/2	B-Application
.	O
</s>
<s>
Microsoft	O
agreed	O
to	O
write	O
a	O
custom	O
version	O
of	O
MS-DOS	B-Application
4.0	I-Application
for	O
ICL	O
that	O
would	O
take	O
advantage	O
of	O
the	O
extra	O
memory	O
on	O
the	O
ICL	O
computers	O
.	O
</s>
<s>
The	O
PWS	O
was	O
positioned	O
to	O
compete	O
with	O
the	O
IBM	B-Device
Personal	I-Device
System/2	I-Device
(	O
PS/2	B-Device
)	O
and	O
the	O
DEC	O
Vaxstation	O
2000	O
.	O
</s>
<s>
The	O
PWS	O
hardware	O
was	O
a	O
large	O
desktop	O
or	O
floor	O
standing	O
tower	O
chassis	O
,	O
running	O
on	O
an	O
Intel	O
8MHz	O
80286	B-General_Concept
processor	O
that	O
was	O
later	O
superseded	O
by	O
an	O
Intel	O
20MHz	O
80386	B-General_Concept
(	O
DRSPWS386	O
)	O
.	O
</s>
<s>
TCP/IP	B-Protocol
and	O
DECnet	B-Protocol
support	O
was	O
implemented	O
by	O
third	O
parties	O
using	O
packet	O
drivers	O
,	O
as	O
NDIS	B-Application
was	O
not	O
available	O
at	O
this	O
time	O
.	O
</s>
<s>
Languages	O
on	O
DRS20	O
under	O
DRX	O
included	O
Microsoft	B-Language
BASIC	I-Language
,	O
Micro	O
Focus	O
CIS-COBOL	O
,	O
Pascal	B-Application
,	O
8085	B-General_Concept
Assembler	O
,	O
</s>
<s>
Digital	O
Research	O
languages	O
including	O
FORTRAN	B-Application
and	O
Pascal	B-Application
.	O
</s>
<s>
Development	O
software	O
on	O
the	O
Unix-based	O
DRS	O
ranges	O
(	O
300	O
to	O
6000	O
)	O
included	O
C	B-Language
,	O
Micro	O
Focus	O
and	O
RM	O
COBOL	B-Application
,	O
EPC	O
C++	B-Language
,	O
FORTRAN	B-Application
and	O
Pascal	B-Application
,	O
and	O
relational	O
databases	O
including	O
Ingres	B-Application
,	O
Informix	B-Application
,	O
Oracle	B-General_Concept
,	O
Sybase	B-Application
and	O
Progress	B-Application
4GL	I-Application
supplied	O
by	O
Progress	O
Software	O
.	O
</s>
