<s>
VAXELN	B-Operating_System
(	O
typically	O
pronounced	O
"	O
VAX-elan	O
"	O
)	O
is	O
a	O
discontinued	O
real-time	B-Operating_System
operating	I-Operating_System
system	I-Operating_System
for	O
the	O
VAX	B-Device
family	O
of	O
computers	O
produced	O
by	O
the	O
Digital	O
Equipment	O
Corporation	O
(	O
DEC	O
)	O
of	O
Maynard	O
,	O
Massachusetts	O
.	O
</s>
<s>
As	O
with	O
RSX-11	B-Application
and	O
VMS	B-Operating_System
,	O
Dave	O
Cutler	O
was	O
the	O
principal	O
force	O
behind	O
the	O
development	O
of	O
this	O
operating	O
system	O
.	O
</s>
<s>
Initial	O
target	O
platforms	O
for	O
VAXELN	B-Operating_System
were	O
the	O
backplane	B-Architecture
interconnect	O
computers	O
such	O
as	O
the	O
model	O
code-named	O
Scorpio	O
.	O
</s>
<s>
When	O
VAXELN	B-Operating_System
was	O
well	O
under	O
way	O
,	O
Cutler	O
spearheaded	O
the	O
next	O
project	O
,	O
the	O
MicroVAX	O
I	O
,	O
the	O
first	O
VAX	B-Device
microcomputer	B-Architecture
.	O
</s>
<s>
Although	O
it	O
was	O
a	O
low-volume	O
product	O
compared	O
with	O
the	O
New	O
England-developed	O
MicroVAX	O
II	O
,	O
the	O
MicroVAX	O
I	O
demonstrated	O
the	O
set	O
of	O
architectural	O
decisions	O
needed	O
to	O
support	O
a	O
single-board	O
implementation	O
of	O
the	O
VAX	B-Device
computer	O
family	O
,	O
and	O
it	O
also	O
provided	O
a	O
platform	O
for	O
embedded	B-Architecture
system	I-Architecture
applications	O
written	O
for	O
VAXELN	B-Operating_System
.	O
</s>
<s>
The	O
VAXELN	B-Operating_System
team	O
made	O
the	O
decision	O
,	O
for	O
the	O
first	O
release	O
,	O
to	O
use	O
the	O
programming	O
language	O
Pascal	B-Application
as	O
its	O
system	B-Language
programming	I-Language
language	I-Language
.	O
</s>
<s>
Other	O
languages	O
,	O
including	O
C	B-Language
,	O
Ada	B-Language
,	O
and	O
Fortran	B-Application
were	O
supported	O
in	O
later	O
releases	O
of	O
the	O
system	O
as	O
optional	O
extras	O
.	O
</s>
<s>
A	O
relational	B-Application
database	I-Application
,	O
named	O
VAX	B-Device
Rdb/ELN	O
was	O
another	O
optional	O
component	O
of	O
the	O
system	O
.	O
</s>
<s>
Later	O
versions	O
of	O
VAXELN	B-Operating_System
supported	O
an	O
X11	B-Operating_System
server	I-Operating_System
named	O
EWS	O
(	O
VAXELN	B-Operating_System
Window	O
Server	O
)	O
.	O
</s>
<s>
VAXELN	B-Operating_System
with	O
EWS	O
was	O
used	O
as	O
the	O
operating	O
system	O
for	O
the	O
VT1300	O
X	B-Protocol
terminal	I-Protocol
,	O
and	O
was	O
sometimes	O
used	O
to	O
convert	O
old	O
VAXstation	B-Device
hardware	O
into	O
X	B-Protocol
terminals	I-Protocol
.	O
</s>
<s>
Beginning	O
with	O
version	O
4.3	O
,	O
VAXELN	B-Operating_System
gained	O
support	O
for	O
TCP/IP	B-Protocol
networking	O
and	O
a	O
subset	O
of	O
POSIX	O
APIs	B-General_Concept
.	O
</s>
<s>
VAXELN	B-Operating_System
allowed	O
the	O
creation	O
of	O
a	O
self-contained	O
embedded	B-Architecture
system	I-Architecture
application	O
that	O
would	O
run	O
on	O
VAX	B-Device
(	O
and	O
later	O
MicroVAX	O
)	O
hardware	O
with	O
no	O
other	O
operating	O
system	O
present	O
.	O
</s>
<s>
The	O
system	O
was	O
debuted	O
in	O
Las	O
Vegas	O
in	O
the	O
early	O
1980s	O
,	O
with	O
a	O
variety	O
of	O
amusing	O
application	B-Application
software	I-Application
written	O
by	O
the	O
development	O
team	O
,	O
ranging	O
from	O
a	O
system	O
that	O
composed	O
and	O
played	O
minuets	O
to	O
a	O
robotic	O
system	O
that	O
played	O
and	O
solved	O
the	O
Tower	B-Language
of	I-Language
Hanoi	I-Language
puzzle	I-Language
.	O
</s>
<s>
VAXELN	B-Operating_System
was	O
not	O
ported	O
to	O
the	O
DEC	B-Device
Alpha	I-Device
architecture	O
,	O
and	O
instead	O
was	O
replaced	O
with	O
a	O
Digital-supported	O
port	O
of	O
VxWorks	B-Operating_System
to	O
Alpha	B-Device
,	O
and	O
a	O
VAXELN	B-Operating_System
application	O
programming	O
interface	O
(	O
API	B-General_Concept
)	O
compatibility	O
layer	O
for	O
that	O
platform	O
.	O
</s>
<s>
In	O
1999	O
,	O
SMART	O
Modular	O
Technologies	O
acquired	O
Compaq	O
's	O
(	O
formerly	O
Digital	O
's	O
)	O
embedded	B-Architecture
systems	I-Architecture
division	O
,	O
which	O
included	O
VAXELN	B-Operating_System
.	O
</s>
<s>
To	O
avoid	O
litigation	O
,	O
DEC	O
quickly	O
renamed	O
it	O
to	O
VAXELN	B-Operating_System
by	O
dropping	O
the	O
A	O
,	O
much	O
to	O
the	O
disgruntlement	O
of	O
the	O
developers	O
.	O
</s>
