<s>
The	O
HP	B-Device
3000	I-Device
series	O
is	O
a	O
family	O
of	O
16-bit	B-Device
and	O
32-bit	O
minicomputers	B-Architecture
from	O
Hewlett-Packard	O
.	O
</s>
<s>
It	O
was	O
designed	O
to	O
be	O
the	O
first	O
minicomputer	B-Architecture
with	O
full	O
support	O
for	O
time-sharing	B-General_Concept
in	O
the	O
hardware	O
and	O
the	O
operating	B-General_Concept
system	I-General_Concept
,	O
features	O
that	O
had	O
mostly	O
been	O
limited	O
to	O
mainframes	B-Architecture
,	O
or	O
retrofitted	O
to	O
existing	O
systems	O
like	O
Digital	O
's	O
PDP-11	B-Device
,	O
on	O
which	O
Unix	B-Application
was	O
implemented	O
.	O
</s>
<s>
The	O
original	O
HP	B-Device
3000	I-Device
hardware	O
was	O
withdrawn	O
from	O
the	O
market	O
in	O
1973	O
to	O
address	O
performance	O
problems	O
and	O
OS	O
stability	O
.	O
</s>
<s>
After	O
reintroduction	O
in	O
1974	O
,	O
it	O
went	O
on	O
to	O
become	O
a	O
reliable	O
and	O
powerful	O
business	O
system	O
,	O
one	O
that	O
regularly	O
won	O
HP	O
business	O
from	O
companies	O
that	O
had	O
been	O
using	O
IBM	O
's	O
mainframes	B-Architecture
.	O
</s>
<s>
Hewlett-Packard	O
'	O
s	O
initial	O
naming	O
referred	O
to	O
the	O
computer	O
as	O
the	O
System/3000	O
,	O
and	O
then	O
called	O
it	O
the	O
HP	B-Device
3000	I-Device
.	O
</s>
<s>
The	O
HP	B-Device
3000	I-Device
originally	O
used	O
a	O
16-bit	B-Device
CISC	B-Architecture
stack	B-Application
machine	I-Application
processor	O
architecture	O
,	O
first	O
implemented	O
with	O
Transistor-transistor	B-General_Concept
logic	I-General_Concept
,	O
and	O
later	O
with	O
Silicon	B-Algorithm
on	I-Algorithm
Sapphire	I-Algorithm
chips	O
beginning	O
with	O
the	O
Series	O
33	O
in	O
1979	O
.	O
</s>
<s>
In	O
the	O
early	O
1980s	O
,	O
HP	O
began	O
development	O
of	O
a	O
new	O
RISC	B-Architecture
processor	I-Architecture
,	O
which	O
emerged	O
as	O
the	O
PA-RISC	B-Device
platform	O
.	O
</s>
<s>
The	O
HP	B-Device
3000	I-Device
CPU	O
was	O
reimplemented	O
as	O
an	O
emulator	B-Application
running	O
on	O
PA-RISC	B-Device
and	O
a	O
recompiled	O
version	O
of	O
the	O
MPE	B-Operating_System
operating	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
The	O
RISC-based	B-Architecture
systems	I-Architecture
were	O
known	O
as	O
the	O
"	O
XL	O
"	O
versions	O
,	O
while	O
the	O
earlier	O
CISC	B-Architecture
models	O
retroactively	O
became	O
the	O
"	O
Classic	O
"	O
series	O
.	O
</s>
<s>
Identical	O
machines	O
running	O
HP-UX	B-Application
instead	O
of	O
MPE	B-Operating_System
XL	I-Operating_System
were	O
known	O
as	O
the	O
HP	B-Device
9000	I-Device
.	O
</s>
<s>
They	O
later	O
found	O
a	O
small	O
company	O
,	O
DSI	O
,	O
working	O
for	O
Union	O
Carbide	O
,	O
that	O
had	O
essentially	O
"	O
stretched	O
"	O
DEC	O
's	O
PDP-8	B-Device
from	O
12	O
to	O
16-bits	B-Device
.	O
</s>
<s>
The	O
DSI	O
design	O
became	O
the	O
basis	O
for	O
the	O
HP	B-Device
2100	I-Device
,	O
introduced	O
in	O
1966	O
,	O
initially	O
marketed	O
as	O
a	O
"	O
test	O
and	O
instrumentation	O
computer	O
"	O
.	O
</s>
<s>
This	O
led	O
to	O
a	O
series	O
of	O
updated	O
versions	O
with	O
better	O
input/output	B-General_Concept
to	O
handle	O
business	O
workflows	O
.	O
</s>
<s>
In	O
1968	O
,	O
the	O
line	O
was	O
further	O
expanded	O
with	O
the	O
HP	O
2000	O
,	O
a	O
series	O
of	O
machines	O
that	O
were	O
made	O
up	O
from	O
collections	O
of	O
parts	O
from	O
the	O
HP	B-Device
2100	I-Device
family	O
,	O
with	O
most	O
systems	O
using	O
a	O
low-end	O
2100	O
series	O
CPU	O
as	O
a	O
terminal	O
controller	O
and	O
high-end	O
CPU	O
as	O
the	O
main	O
processor	O
.	O
</s>
<s>
The	O
systems	O
ran	O
HP	B-Language
Time-Shared	I-Language
BASIC	I-Language
,	O
and	O
depending	O
on	O
the	O
model	O
,	O
could	O
support	O
between	O
16	O
and	O
32	O
users	O
at	O
one	O
time	O
.	O
</s>
<s>
The	O
machines	O
were	O
an	O
immediate	O
success	O
,	O
quickly	O
becoming	O
one	O
of	O
the	O
best-selling	O
systems	O
in	O
the	O
timesharing	B-General_Concept
market	O
,	O
and	O
propelling	O
HP	O
to	O
become	O
the	O
3rd	O
largest	O
minicomputer	B-Architecture
vendor	O
.	O
</s>
<s>
Two	O
basic	O
systems	O
were	O
outlined	O
,	O
the	O
"	O
Alpha	B-Device
"	O
was	O
essentially	O
an	O
HP	B-Device
2100	I-Device
built	O
using	O
newer	O
components	O
and	O
improved	O
memory	O
handling	O
,	O
while	O
"	O
Omega	O
"	O
was	O
a	O
much	O
larger	O
32-bit	O
design	O
that	O
would	O
support	O
large	O
numbers	O
of	O
users	O
.	O
</s>
<s>
However	O
,	O
almost	O
all	O
development	O
took	O
place	O
within	O
Omega	O
,	O
and	O
few	O
,	O
if	O
any	O
,	O
engineers	O
were	O
active	O
on	O
Alpha	B-Device
during	O
1969	O
.	O
</s>
<s>
In	O
contrast	O
to	O
the	O
16-bit	B-Device
Alpha	B-Device
,	O
Omega	O
would	O
be	O
a	O
32-bit	O
computer	O
with	O
up	O
to	O
4MB	O
of	O
main	O
memory	O
shared	O
among	O
up	O
to	O
four	O
central	B-General_Concept
processing	I-General_Concept
units	I-General_Concept
(	O
CPUs	O
)	O
.	O
</s>
<s>
The	O
CPUs	O
were	O
designed	O
to	O
be	O
programmed	O
in	O
a	O
high	B-Language
level	I-Language
language	I-Language
,	O
like	O
the	O
successful	O
models	O
from	O
Burroughs	O
that	O
were	O
programmed	O
in	O
a	O
custom	O
systems	B-Language
programming	I-Language
language	I-Language
rather	O
than	O
assembler	B-Application
.	O
</s>
<s>
Support	O
for	O
multiprogramming	O
and	O
memory	B-General_Concept
protection	I-General_Concept
would	O
be	O
built	O
in	O
.	O
</s>
<s>
This	O
resulted	O
in	O
several	O
employees	O
wearing	O
black-velvet	O
armbands	O
to	O
mourn	O
the	O
death	O
of	O
the	O
project	O
,	O
and	O
some	O
dismay	O
over	O
being	O
reassigned	O
to	O
"	O
just	O
another	O
16-bit	B-Device
machine.	O
"	O
</s>
<s>
By	O
this	O
time	O
the	O
small	O
amount	O
of	O
development	O
on	O
Alpha	B-Device
had	O
changed	O
the	O
nature	O
of	O
the	O
project	O
significantly	O
.	O
</s>
<s>
Originally	O
conceived	O
as	O
an	O
updated	O
HP	B-Device
2100	I-Device
,	O
it	O
had	O
become	O
essentially	O
a	O
small	O
Omega	O
,	O
adopting	O
its	O
virtual	B-Architecture
memory	I-Architecture
and	O
stack	B-Application
machine	I-Application
design	O
that	O
supported	O
high	B-Language
level	I-Language
languages	I-Language
,	O
but	O
limited	O
to	O
a	O
16-bit	B-Device
design	O
with	O
a	O
maximum	O
of	O
64kWord	O
main	O
memory	O
(	O
128kB	O
)	O
,	O
only	O
a	O
single	O
accumulator	B-General_Concept
,	O
and	O
lacking	O
Omega	O
's	O
powerful	O
input/output	B-General_Concept
systems	O
.	O
</s>
<s>
When	O
the	O
plan	O
to	O
continue	O
the	O
development	O
of	O
Alpha	B-Device
was	O
presented	O
,	O
George	O
Newman	O
,	O
who	O
replaced	O
Perkins	O
as	O
the	O
General	O
Manager	O
of	O
the	O
computer	O
division	O
,	O
was	O
concerned	O
that	O
the	O
team	O
was	O
once	O
again	O
designing	O
a	O
machine	O
that	O
could	O
not	O
be	O
delivered	O
.	O
</s>
<s>
Prior	O
minicomputers	B-Architecture
were	O
generally	O
used	O
in	O
a	O
fashion	O
similar	O
to	O
modern	O
microcomputers	B-Architecture
,	O
used	O
by	O
a	O
single	O
user	O
,	O
and	O
often	O
dedicated	O
to	O
a	O
single	O
particular	O
task	O
like	O
operating	O
machinery	O
.	O
</s>
<s>
This	O
was	O
true	O
for	O
many	O
contemporary	O
designs	O
like	O
the	O
PDP-8	B-Device
and	O
Data	B-Device
General	I-Device
Nova	I-Device
.	O
</s>
<s>
It	O
was	O
the	O
HP	O
2000	O
's	O
ability	O
to	O
perform	O
timesharing	B-General_Concept
that	O
made	O
it	O
a	O
success	O
in	O
a	O
market	O
of	O
similar	O
machines	O
.	O
</s>
<s>
The	O
ability	O
to	O
support	O
multiple	O
users	O
running	O
different	O
programs	O
was	O
previously	O
limited	O
to	O
mainframe	B-Architecture
computers	I-Architecture
,	O
and	O
a	O
further	O
expansion	O
of	O
this	O
capability	O
was	O
a	O
key	O
design	O
concept	O
for	O
the	O
original	O
Omega	O
.	O
</s>
<s>
When	O
Alpha	B-Device
emerged	O
as	O
an	O
Omega-like	O
design	O
,	O
it	O
initially	O
followed	O
the	O
same	O
model	O
of	O
multi-user	O
support	O
,	O
which	O
was	O
in	O
turn	O
based	O
on	O
the	O
HP	O
2000	O
concept	O
.	O
</s>
<s>
This	O
allows	O
the	O
main	O
operating	B-General_Concept
system	I-General_Concept
to	O
be	O
greatly	O
simplified	O
,	O
simply	O
loading	O
up	O
user	O
programs	O
as	O
they	O
appear	O
from	O
the	O
front-end	O
,	O
running	O
them	O
in	O
a	O
round-robin	O
fashion	O
with	O
other	O
users	O
 '	O
programs	O
,	O
and	O
then	O
delivering	O
the	O
results	O
.	O
</s>
<s>
In	O
most	O
respects	O
,	O
this	O
was	O
a	O
batch	B-General_Concept
processing	I-General_Concept
system	O
,	O
much	O
of	O
the	O
complexity	O
of	O
multi-user	O
support	O
was	O
isolated	O
in	O
the	O
separate	O
front-end	O
processor	O
.	O
</s>
<s>
As	O
development	O
re-started	O
on	O
Alpha	B-Device
,	O
this	O
concept	O
was	O
re-examined	O
and	O
the	O
decision	O
was	O
made	O
to	O
expand	O
the	O
operating	B-General_Concept
system	I-General_Concept
to	O
support	O
multiprogramming	O
directly	O
.	O
</s>
<s>
This	O
resulted	O
in	O
the	O
system	O
becoming	O
three-in-one	O
,	O
with	O
the	O
main	O
portion	O
being	O
dedicated	O
to	O
timesharing	B-General_Concept
but	O
also	O
offering	O
real-time	O
support	O
and	O
batch	B-General_Concept
mode	I-General_Concept
.	O
</s>
<s>
The	O
resulting	O
system	O
,	O
ultimately	O
known	O
as	O
Multi-Programming	B-Operating_System
Executive	I-Operating_System
(	O
MPE	B-Operating_System
)	O
,	O
would	O
be	O
among	O
the	O
most	O
advanced	O
of	O
its	O
era	O
.	O
</s>
<s>
When	O
the	O
ten	O
groups	O
within	O
the	O
operating	B-General_Concept
system	I-General_Concept
team	O
came	O
together	O
to	O
describe	O
their	O
section	O
of	O
the	O
system	O
,	O
they	O
found	O
that	O
it	O
was	O
too	O
large	O
to	O
fit	O
in	O
memory	O
,	O
let	O
alone	O
have	O
room	O
for	O
user	O
programs	O
.	O
</s>
<s>
However	O
,	O
MPE	B-Operating_System
development	O
was	O
by	O
this	O
time	O
far	O
behind	O
schedule	O
.	O
</s>
<s>
Peachy	O
had	O
previously	O
worked	O
on	O
the	O
first	O
timesharing	B-General_Concept
systems	O
at	O
Dartmouth	O
College	O
,	O
and	O
had	O
since	O
worked	O
at	O
General	O
Electric	O
and	O
Memorex	O
.	O
</s>
<s>
As	O
a	O
result	O
of	O
the	O
MPE	B-Operating_System
delays	O
,	O
the	O
ship	O
date	O
was	O
pushed	O
back	O
from	O
August	O
to	O
November	O
1972	O
,	O
and	O
MPE	B-Operating_System
was	O
reduced	O
solely	O
to	O
timesharing	B-General_Concept
support	O
,	O
with	O
additional	O
features	O
slated	O
to	O
arrive	O
through	O
1973	O
.	O
</s>
<s>
In	O
a	O
training	O
session	O
that	O
December	O
,	O
a	O
new	O
version	O
of	O
MPE	B-Operating_System
was	O
able	O
to	O
run	O
four	O
users	O
and	O
crashed	O
only	O
once	O
every	O
two	O
hours	O
.	O
</s>
<s>
The	O
schedule	O
for	O
MPE	B-Operating_System
features	O
continued	O
to	O
be	O
pushed	O
back	O
,	O
and	O
the	O
estimated	O
number	O
of	O
machine	O
sales	O
continued	O
to	O
be	O
reduced	O
.	O
</s>
<s>
The	O
system	O
then	O
entered	O
a	O
six	O
month	O
period	O
of	O
redevelopment	O
of	O
both	O
MPE	B-Operating_System
and	O
the	O
hardware	O
.	O
</s>
<s>
MPE	B-Operating_System
emerged	O
as	O
MPE-8	O
,	O
officially	O
ending	O
real-time	O
support	O
.	O
</s>
<s>
This	O
new	O
"	O
CX	O
"	O
model	O
replaced	O
core	B-General_Concept
memory	I-General_Concept
with	O
semiconductor	B-Architecture
memory	I-Architecture
and	O
replaced	O
the	O
wire	O
wrapped	O
CPU	O
boards	O
with	O
surface	O
mounted	O
components	O
.	O
</s>
<s>
MPE-C	O
added	O
COBOL	B-Application
and	O
RPG	B-Language
languages	O
,	O
perhaps	O
the	O
first	O
mini	O
to	O
offer	O
the	O
former	O
.	O
</s>
<s>
As	O
part	O
of	O
the	O
CX	O
release	O
,	O
HP	O
shipped	O
IMAGE	B-Application
,	O
a	O
$	O
10,000	O
database	O
system	O
written	O
to	O
the	O
CODASYL	B-Language
standards	O
.	O
</s>
<s>
IMAGE	B-Application
is	O
the	O
primary	O
reason	O
the	O
HP	B-Device
3000	I-Device
eventually	O
became	O
a	O
success	O
.	O
</s>
<s>
By	O
1984	O
HP	O
introduced	O
the	O
HP3000	B-Device
Series	O
37	O
,	O
the	O
first	O
model	O
that	O
ran	O
in	O
offices	O
without	O
special	O
cooling	O
or	O
flooring	O
requirements	O
.	O
</s>
<s>
The	O
HP	B-Device
3000	I-Device
was	O
one	O
of	O
the	O
last	O
proprietary	O
minicomputer	B-Architecture
systems	O
whose	O
manufacture	O
was	O
curtailed	O
by	O
its	O
vendor	O
,	O
outlasting	O
the	O
PDP-11-descended	O
Digital	O
Equipment	O
Corporation	O
VAX	B-Device
,	O
which	O
was	O
acquired	O
by	O
Compaq	O
and	O
then	O
ultimately	O
by	O
Hewlett-Packard	O
.	O
</s>
<s>
Support	O
from	O
HP	O
to	O
customers	O
for	O
the	O
HP	B-Device
3000	I-Device
continued	O
through	O
December	O
31	O
,	O
2010	O
.	O
</s>
<s>
Some	O
customers	O
continue	O
to	O
use	O
the	O
HP	B-Device
3000	I-Device
in	O
companies	O
worldwide	O
,	O
especially	O
in	O
manufacturing	O
and	O
e-commerce	O
industries	O
,	O
while	O
others	O
have	O
migrated	O
to	O
business	O
server	O
systems	O
made	O
by	O
HP	O
and	O
others	O
.	O
</s>
<s>
In	O
2012	O
,	O
the	O
Stromasys	O
company	O
released	O
a	O
product	O
doing	O
full	O
HP3000	B-Device
hardware	O
emulation	B-Application
on	O
x86-64	B-Device
servers	O
running	O
Red	O
Hat	O
Linux	O
or	O
CentOS	O
.	O
</s>
<s>
That	O
product	O
operates	O
as	O
a	O
virtualized	O
instance	O
of	O
the	O
HP	B-Device
3000	I-Device
server	O
hardware	O
.	O
</s>
<s>
Starting	O
in	O
2003	O
,	O
HP	O
began	O
a	O
plan	O
to	O
sell	O
a	O
license	O
for	O
the	O
3000	O
's	O
operating	B-General_Concept
system	I-General_Concept
,	O
which	O
can	O
let	O
3000	O
customers	O
run	O
their	O
software	O
on	O
this	O
Stromasys	O
product	O
,	O
known	O
as	O
the	O
HPA/3000	O
.	O
</s>
<s>
The	O
key	O
development	O
that	O
led	O
to	O
the	O
tremendous	O
success	O
of	O
the	O
HP	B-Device
3000	I-Device
was	O
the	O
bundling	O
of	O
the	O
HP-developed	O
network	O
database	O
management	O
system	O
(	O
DBMS	B-General_Concept
)	O
called	O
IMAGE	B-Application
(	O
now	O
called	O
TurboIMAGE/SQL	O
)	O
that	O
was	O
reputedly	O
inspired	O
by	O
the	O
TOTAL	O
DBMS	B-General_Concept
developed	O
by	O
Cincom	B-Application
Systems	I-Application
,	I-Application
Inc	I-Application
.	I-Application
</s>
<s>
IMAGE	B-Application
was	O
an	O
award-winning	O
database	O
anointed	O
by	O
Datamation	O
within	O
two	O
years	O
of	O
the	O
database	O
's	O
introduction	O
.	O
</s>
<s>
It	O
was	O
the	O
first	O
database	O
management	O
system	O
included	O
with	O
a	O
business-class	O
minicomputer	B-Architecture
.	O
</s>
<s>
By	O
bundling	O
IMAGE	B-Application
with	O
the	O
server	O
,	O
HP	O
created	O
an	O
ecosystem	O
of	O
applications	O
and	O
development	O
utilities	O
that	O
could	O
rely	O
upon	O
IMAGE	B-Application
as	O
a	O
data	O
repository	O
in	O
any	O
HP	B-Device
3000	I-Device
.	O
</s>
<s>
Code	O
(	O
reentrant	B-Operating_System
)	O
and	O
data	O
reside	O
in	O
separate	O
variable-length	O
segments	O
,	O
which	O
are	O
32,768	O
"	O
halfwords	O
"	O
(	O
16-bit	B-Device
words	O
)	O
(	O
or	O
,	O
65,536	O
bytes	O
)	O
.	O
</s>
<s>
The	O
operating	B-General_Concept
system	I-General_Concept
,	O
known	O
as	O
MPE	B-Operating_System
(	O
for	O
Multi-Programming	B-Operating_System
Executive	I-Operating_System
)	O
,	O
loads	O
code	O
segments	O
from	O
program	O
files	O
and	O
segmented	O
Library	O
(	O
SL	O
)	O
files	O
as	O
needed	O
,	O
up	O
to	O
256	O
segments	O
in	O
one	O
process	O
.	O
</s>
<s>
With	O
8	O
bits	O
to	O
specify	O
segment	O
,	O
and	O
16	B-Device
bits	I-Device
within	O
a	O
segment	O
a	O
program	O
could	O
have	O
effectively	O
have	O
a	O
24	O
bit	O
address	O
or	O
16MB	O
.	O
</s>
<s>
This	O
was	O
compared	O
to	O
most	O
16	B-Device
bit	I-Device
computers	O
like	O
the	O
PDP-11	B-Device
or	O
IBM	O
System/34	O
that	O
had	O
64KB	O
of	O
address	O
space	O
for	O
code	O
and	O
data	O
.	O
</s>
<s>
The	O
bigger	O
limitation	O
was	O
the	O
data	O
segment	O
and	O
stack	B-Application
segment	O
,	O
which	O
were	O
also	O
64KB	O
.	O
</s>
<s>
Some	O
procedures	O
worked	O
around	O
this	O
by	O
requiring	O
the	O
caller	O
to	O
pass	O
in	O
an	O
array	O
from	O
their	O
own	O
stack	B-Application
or	O
data	O
segment	O
to	O
hold	O
all	O
state	O
information	O
,	O
similar	O
to	O
modern	O
object-oriented	O
languages	O
where	O
methods	O
are	O
applied	O
to	O
objects	O
passed	O
are	O
allocated	O
by	O
the	O
caller	O
.	O
</s>
<s>
Systems	O
programming	O
was	O
done	O
in	O
SPL	O
(	O
System	B-Language
Programming	I-Language
Language	I-Language
)	O
,	O
an	O
ALGOL-like	B-Language
language	O
,	O
but	O
allowing	O
inline	O
assembler	B-Application
,	O
and	O
other	O
direct	O
access	O
to	O
the	O
instruction	B-General_Concept
set	I-General_Concept
.	O
</s>
<s>
The	O
standard	O
terminals	O
for	O
the	O
HP	B-Device
3000	I-Device
were	O
the	O
HP	B-General_Concept
2640	I-General_Concept
series	O
,	O
which	O
supported	O
block	O
mode	O
data	O
entry	O
from	O
forms	O
(	O
like	O
IBM	O
's	O
mainframe-based	O
CICS	B-Application
)	O
,	O
as	O
well	O
as	O
character	O
mode	O
.	O
</s>
<s>
The	O
HP	B-Device
3000	I-Device
family	O
's	O
generations	O
were	O
divided	O
into	O
the	O
"	O
Classic	O
"	O
(	O
16-bit	B-Device
)	O
and	O
then	O
"	O
XL	O
"	O
(	O
later	O
IX	O
–	O
32-bit	O
)	O
families	O
following	O
the	O
introduction	O
of	O
systems	O
based	O
on	O
HP	O
's	O
PA-RISC	B-Device
chips	O
for	O
3000s	O
in	O
early	O
1987	O
.	O
</s>
<s>
These	O
newer	O
XL	O
systems	O
were	O
not	O
binary	O
compatible	O
with	O
the	O
Classics	O
,	O
but	O
would	O
transparently	O
run	O
Classic	O
code	O
via	O
an	O
emulator	B-Application
,	O
one	O
that	O
HP	O
integrated	O
into	O
the	O
MPE	B-Operating_System
XL	I-Operating_System
operating	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
(	O
Classic	O
code	O
could	O
optionally	O
be	O
translated	O
to	O
native	O
PA-RISC	B-Device
code	O
via	O
OCTCOMP	O
,	O
the	O
Object	O
Code	O
Translator/COMPiler	O
...	O
such	O
code	O
ran	O
at	O
native	O
speed	O
,	O
but	O
was	O
still	O
subject	O
to	O
Classic	O
stack	B-Application
and	O
memory	O
size	O
limitations	O
)	O
.	O
</s>
<s>
The	O
earlier	O
"	O
Classic	O
"	O
machines	O
were	O
based	O
on	O
a	O
custom	O
CISC	B-Architecture
processor	I-Architecture
.	O
</s>
<s>
From	O
about	O
1988	O
onward	O
,	O
HP	B-Device
3000s	I-Device
using	O
PA-RISC	B-Device
processors	O
began	O
shipping	O
in	O
volume	O
.	O
</s>
<s>
By	O
1995	O
these	O
PA-RISC	B-Device
systems	O
effectively	O
displaced	O
the	O
older	O
family	O
of	O
machines	O
from	O
use	O
.	O
</s>
<s>
HP	B-Device
3000	I-Device
and	O
many	O
HP	B-Device
9000	I-Device
machines	O
used	O
the	O
HP	B-Architecture
Precision	I-Architecture
Bus	I-Architecture
.	O
</s>
<s>
The	O
PA-RISC	B-Device
based	O
HP	B-Device
3000	I-Device
's	O
operating	B-General_Concept
system	I-General_Concept
was	O
written	O
primarily	O
in	O
Modcal	O
,	O
HP	O
's	O
extended	O
version	O
of	O
Pascal	B-Application
.	O
</s>
<s>
Large	O
portions	O
of	O
the	O
earlier	O
MPE	B-Operating_System
V	O
operating	B-General_Concept
system	I-General_Concept
,	O
written	O
in	O
SPL	O
,	O
are	O
still	O
used	O
as	O
part	O
of	O
MPE	B-Operating_System
XL	I-Operating_System
and	O
MPE/iX	B-Operating_System
on	O
PA-RISC	B-Device
.	O
</s>
<s>
A	O
few	O
subsystems	O
(	O
e.g.	O
,	O
TurboIMAGE	B-Application
)	O
are	O
written	O
in	O
PSPL	O
(	O
Portable	O
SPL	O
)	O
.	O
</s>
<s>
A	O
small	O
portion	O
of	O
MPE	B-Operating_System
XL	I-Operating_System
and	O
MPE/iX	B-Operating_System
is	O
written	O
in	O
PA-RISC	B-Device
assembly	O
language	O
.	O
</s>
<s>
The	O
3000	O
series	O
operating	B-General_Concept
system	I-General_Concept
was	O
originally	O
styled	O
the	O
Multi-Programming	B-Operating_System
Executive	I-Operating_System
,	O
MPE	B-Operating_System
(	O
later	O
called	O
MPE	B-Operating_System
XL	I-Operating_System
and	O
then	O
,	O
after	O
POSIX	O
compliance	O
was	O
added	O
in	O
versions	O
5.0-5.5	O
,	O
MPE/iX	B-Operating_System
)	O
.	O
</s>
<s>
The	O
earliest	O
versions	O
of	O
the	O
system	O
used	O
only	O
HP	O
's	O
proprietary	O
SPL	O
systems	B-Language
programming	I-Language
language	I-Language
and	O
BASIC	O
.	O
</s>
<s>
These	O
System	O
3000s	O
used	O
a	O
command-line	O
interpreter	O
,	O
with	O
a	O
three-level	O
hierarchical	O
file	O
system	O
,	O
and	O
utilities	O
such	O
as	O
compilers	O
would	O
resemble	O
"	O
run	O
fortran.pub.sys	O
"	O
rather	O
than	O
allowing	O
programs	O
to	O
be	O
run	O
as	O
keyword	O
commands	O
.	O
</s>
<s>
Later	O
the	O
systems	O
gained	O
a	O
wide	O
range	O
of	O
languages	O
including	O
COBOL	B-Application
and	O
FORTRAN	B-Application
,	O
Pascal	B-Application
,	O
C	B-Language
,	O
and	O
even	O
a	O
version	O
of	O
RPG	B-Language
to	O
assist	O
in	O
winning	O
business	O
away	O
from	O
IBM	O
.	O
</s>
<s>
People	O
who	O
used	O
the	O
HP	B-Device
3000	I-Device
noticed	O
from	O
the	O
1970s	O
onward	O
that	O
machines	O
were	O
more	O
reliable	O
compared	O
to	O
other	O
mainframe	B-Architecture
and	O
minicomputers	B-Architecture
of	O
the	O
time	O
.	O
</s>
<s>
At	O
times	O
the	O
HP	B-Device
3000	I-Device
suffered	O
from	O
peripheral	O
support	O
delays	O
or	O
gaps	O
caused	O
by	O
HP	O
's	O
decision	O
to	O
delay	O
supporting	O
,	O
or	O
not	O
support	O
at	O
all	O
,	O
some	O
peripherals	O
on	O
the	O
HP	B-Device
3000	I-Device
platform	O
—	O
some	O
of	O
which	O
were	O
supported	O
on	O
the	O
identical	O
HP	B-Device
9000	I-Device
hardware	O
.	O
</s>
<s>
Most	O
current	O
computer	O
instruction	B-General_Concept
sets	I-General_Concept
are	O
based	O
on	O
a	O
general	O
purpose	O
register	O
model	O
.	O
</s>
<s>
The	O
processor	O
and	O
memory	O
architecture	O
of	O
the	O
classic	O
HP	B-Device
3000	I-Device
were	O
based	O
on	O
a	O
stack	B-Application
machine	I-Application
model	O
,	O
like	O
HP	O
's	O
well-known	O
line	O
of	O
RPN	O
calculators	O
.	O
</s>
<s>
It	O
was	O
said	O
to	O
be	O
inspired	O
by	O
the	O
famous	O
stack-based	O
Burroughs	B-Device
large	I-Device
systems	I-Device
.	O
</s>
<s>
Rather	O
than	O
having	O
a	O
small	O
number	O
of	O
registers	O
,	O
for	O
example	O
only	O
an	O
AX	O
and	O
BX	O
register	O
in	O
the	O
case	O
of	O
the	O
HP	B-Device
1000	I-Device
,	O
operands	O
would	O
be	O
pushed	O
on	O
the	O
same	O
stack	B-Application
used	O
to	O
store	O
local	O
variables	O
and	O
return	O
addresses	O
.	O
</s>
<s>
The	O
16-bit	B-Device
microcoded	B-Device
machines	O
(	O
Series	O
I	O
,	O
II	O
,	O
III	O
,	O
30	O
,	O
33	O
,	O
39	O
,	O
40	O
,	O
42	O
,	O
44	O
,	O
48	O
,	O
52	O
,	O
58	O
,	O
64	O
,	O
68	O
,	O
70	O
,	O
37	O
,	O
...	O
)	O
implement	O
a	O
16-bit	B-General_Concept
word	I-General_Concept
addressed	I-General_Concept
,	O
byte-addressable	B-General_Concept
,	O
segmented	O
,	O
Harvard	B-Architecture
,	O
Stack	B-Application
Instruction	B-General_Concept
Set	I-General_Concept
Architecture	I-General_Concept
(	O
ISA	O
)	O
.	O
</s>
<s>
Most	O
of	O
the	O
~	O
214	O
instructions	O
are	O
16	B-Device
bits	I-Device
wide	O
.	O
</s>
<s>
Stack	B-Application
operations	O
pack	O
2	O
per	O
16-bit	B-Device
word	O
and	O
the	O
remaining	O
few	O
are	O
32	O
bits	O
wide	O
.	O
</s>
<s>
Later	O
32-bit	O
models	O
used	O
HP	O
's	O
PA-RISC	B-Device
general	O
register-based	O
RISC	B-Architecture
architecture	O
.	O
</s>
<s>
After	O
the	O
enterprise	O
computing	O
market	O
shifted	O
toward	O
commodity	O
Unix	B-Application
systems	I-Application
from	O
a	O
wide	O
range	O
of	O
vendors	O
—	O
systems	O
that	O
HP	O
had	O
also	O
been	O
promoting	O
—	O
in	O
November	O
2001	O
Hewlett-Packard	O
announced	O
that	O
a	O
period	O
it	O
called	O
the	O
end-of-life	O
for	O
the	O
HP	B-Device
3000	I-Device
would	O
wrap	O
up	O
at	O
the	O
end	O
of	O
2006	O
,	O
and	O
that	O
no	O
new	O
systems	O
would	O
be	O
sold	O
by	O
HP	O
after	O
2003	O
.	O
</s>
<s>
In	O
early	O
2006	O
,	O
Hewlett-Packard	O
announced	O
that	O
limited	O
vendor	O
support	O
for	O
the	O
HP	B-Device
3000	I-Device
would	O
be	O
extended	O
by	O
two	O
years	O
for	O
certain	O
clients	O
or	O
geographic	O
regions	O
.	O
</s>
<s>
Open	O
source	O
software	O
resources	O
,	O
including	O
commodity	O
tools	O
,	O
for	O
the	O
3000	O
's	O
MPE/iX	B-Operating_System
operating	B-General_Concept
system	I-General_Concept
are	O
maintained	O
in	O
a	O
website	O
by	O
Applied	O
Technologies	O
.	O
</s>
<s>
The	O
HP	B-Device
3000	I-Device
has	O
enjoyed	O
one	O
of	O
the	O
longest	O
lifetimes	O
for	O
any	O
business	O
computer	O
system	O
.	O
</s>
<s>
These	O
enterprise-grade	O
computers	O
have	O
outlasted	O
the	O
highly	O
regarded	O
PDP-11	B-Device
and	O
VAX	B-Device
series	O
,	O
although	O
OpenVMS	B-Operating_System
operating	B-General_Concept
system	I-General_Concept
is	O
still	O
being	O
offered	O
on	O
Alpha	B-Device
,	O
IA-64	B-General_Concept
,	O
and	O
x86-64	B-Device
based	O
systems	O
.	O
</s>
<s>
In	O
January	O
2012	O
,	O
Stromasys	O
announced	O
the	O
development	O
of	O
Charon/HPA	O
-3000	O
,	O
which	O
enables	O
secure	O
transfer	O
of	O
HP3000	B-Device
systems	O
to	O
a	O
state-of-the-art	O
environment	O
.	O
</s>
<s>
Stromasys	O
's	O
solution	O
virtualizes	O
the	O
hardware	O
of	O
an	O
existing	O
HP3000	B-Device
system	O
,	O
and	O
enables	O
the	O
MPE/iX	B-Operating_System
operating	B-General_Concept
system	I-General_Concept
,	O
third	O
party	O
applications	O
,	O
and	O
user-developed	O
software	O
to	O
run	O
without	O
any	O
modification	O
whatsoever	O
,	O
on	O
industry-standard	O
Intel	O
servers	O
.	O
</s>
<s>
Multiple	O
independent	O
vendors	O
have	O
purchased	O
HP3000	B-Device
's	O
Operating	B-General_Concept
System	I-General_Concept
Source	O
Code	O
,	O
MPE/iX	B-Operating_System
and	O
are	O
committed	O
to	O
supporting	O
both	O
hardware	O
and	O
software	O
solutions	O
for	O
HP3000	B-Device
systems	O
.	O
</s>
<s>
Beechglen	O
Development	O
,	O
Inc	O
.	O
began	O
hosting	O
HP3000	B-Device
systems	O
in	O
2002	O
.	O
</s>
<s>
In	O
2012	O
Beechglen	O
introduced	O
HP3000	B-Device
compatible	O
custom	O
fibre	O
channel	O
disc	O
arrays	O
using	O
current	O
technology	O
SSD	O
and	O
SATA	O
hard	O
drives	O
,	O
effectively	O
replacing	O
SCSI	O
tape	O
and	O
SCSI	O
disc	O
devices	O
.	O
</s>
<s>
As	O
of	O
January	O
2020	O
,	O
Beechglen	O
is	O
the	O
only	O
vendor	O
that	O
has	O
developed	O
and	O
offers	O
2028	O
MPE	B-Operating_System
CALENDAR	O
intrinsic	O
patches	O
for	O
the	O
MPE/iX	B-Operating_System
Operating	B-General_Concept
system	I-General_Concept
allowing	O
intrinsic	O
dates	O
beyond	O
December	O
31	O
,	O
2027	O
.	O
</s>
