<s>
The	O
Elliott	B-Device
803	I-Device
is	O
a	O
small	O
,	O
medium-speed	O
transistor	O
digital	O
computer	O
which	O
was	O
manufactured	O
by	O
the	O
British	O
company	O
Elliott	O
Brothers	O
in	O
the	O
1960s	O
.	O
</s>
<s>
Over	O
200	O
Elliott	B-Device
803	I-Device
computers	O
were	O
delivered	O
to	O
customers	O
,	O
at	O
a	O
unit	O
price	O
of	O
about	O
£	O
29,000	O
in	O
1960	O
(	O
roughly	O
)	O
.	O
</s>
<s>
The	O
Elliott	B-Device
803	I-Device
was	O
the	O
computer	O
used	O
in	O
the	O
ISI-609	O
,	O
the	O
world	O
's	O
first	O
process	O
or	O
industrial	O
control	O
system	O
,	O
wherein	O
the	O
803	O
was	O
a	O
data	O
logger	O
.	O
</s>
<s>
A	O
significant	O
number	O
of	O
British	O
universities	O
had	O
an	O
Elliott	B-Device
803	I-Device
.	O
</s>
<s>
Elliott	O
subsequently	O
developed	O
(	O
1963	O
)	O
the	O
much	O
faster	O
,	O
software	O
compatible	O
,	O
Elliott	B-Device
503	I-Device
.	O
</s>
<s>
Two	O
complete	O
Elliott	B-Device
803	I-Device
computers	O
survive	O
.	O
</s>
<s>
The	O
803	O
is	O
a	O
transistorised	B-Device
,	O
bit-serial	B-Device
machine	O
;	O
the	O
803B	O
has	O
more	O
parallel	O
paths	O
internally	O
.	O
</s>
<s>
It	O
uses	O
ferrite	O
magnetic-core	O
memory	O
in	O
4096	O
or	O
8192	O
words	O
of	O
40	O
bits	O
,	O
comprising	O
39	O
bits	O
of	O
data	O
with	O
parity	B-Error_Name
.	O
</s>
<s>
The	O
central	B-General_Concept
processing	I-General_Concept
unit	I-General_Concept
(	O
CPU	O
)	O
is	O
housed	O
in	O
one	O
cabinet	O
with	O
a	O
height	O
,	O
width	O
,	O
and	O
depth	O
,	O
of	O
.	O
</s>
<s>
There	O
is	O
an	O
operator	O
's	O
control	B-Device
console	I-Device
,	O
Creed	O
teleprinter	O
and	O
high-speed	O
paper	O
punched	O
tape	O
reader	O
and	O
punch	O
for	O
input/output	B-General_Concept
,	O
using	O
5-track	O
Elliott	O
telecode	O
code	O
,	O
not	O
Baudot	O
.	O
</s>
<s>
The	O
operator	O
's	O
console	O
,	O
about	O
60	O
inches	O
long	O
,	O
allows	O
low-level	O
instructions	O
to	O
be	O
entered	O
manually	O
to	O
manipulate	O
addresses	O
and	O
data	O
and	O
can	O
start	O
,	O
stop	O
and	O
step	O
the	O
machine	O
:	O
there	O
is	O
a	O
loudspeaker	O
(	O
pulsed	O
by	O
the	O
top	O
bit	O
of	O
the	O
instruction	B-General_Concept
register	I-General_Concept
)	O
which	O
allows	O
the	O
operator	O
to	O
judge	O
the	O
status	O
of	O
a	O
computation	O
.	O
</s>
<s>
Instructions	O
and	O
data	O
are	O
based	O
on	O
a	O
39-bit	O
word	O
length	O
with	O
binary	O
representation	O
in	O
2	B-General_Concept
's	I-General_Concept
complement	I-General_Concept
arithmetic	I-General_Concept
.	O
</s>
<s>
The	O
instruction	B-General_Concept
set	I-General_Concept
operates	O
on	O
a	O
single	O
address	O
and	O
single	O
accumulator	O
register	O
,	O
with	O
an	O
additional	O
auxiliary	O
register	O
for	O
double	O
length	O
integer	O
multiply	O
and	O
divide	O
.	O
</s>
<s>
These	O
19-bit	O
instructions	O
are	O
packed	O
two	O
to	O
a	O
word	O
with	O
an	O
additional	O
39th	O
bit	O
between	O
them	O
,	O
the	O
so-called	O
B-line	O
or	O
B	O
digit	O
(	O
the	O
term	O
is	O
a	O
legacy	O
from	O
the	O
Ferranti	B-Device
Mark	I-Device
1	I-Device
computer	O
,	O
where	O
the	O
A-line	O
represented	O
the	O
accumulator	O
and	O
the	O
B-line	O
an	O
instruction	O
modifier	O
,	O
both	O
stored	O
on	O
a	O
Williams	B-General_Concept
tube	I-General_Concept
)	O
.	O
</s>
<s>
Group	O
7	O
is	O
input/output	B-General_Concept
,	O
with	O
the	O
exception	O
of	O
73	O
,	O
which	O
is	O
used	O
for	O
subroutine	O
linkage	O
.	O
</s>
<s>
Since	O
all	O
input	B-General_Concept
and	I-General_Concept
output	I-General_Concept
instructions	O
causes	O
the	O
803	O
to	O
become	O
"	O
busy	O
"	O
if	O
input	B-General_Concept
data	I-General_Concept
is	O
not	O
available	O
or	O
if	O
an	O
output	O
device	O
has	O
not	O
completed	O
a	O
previous	O
operation	O
,	O
interrupts	O
are	O
not	O
needed	O
and	O
are	O
not	O
used	O
for	O
driving	O
the	O
standard	O
peripherals	O
.	O
</s>
<s>
The	O
external	O
equipment	O
raising	O
the	O
interrupt	O
is	O
relied	O
upon	O
to	O
refrain	O
from	O
raising	O
another	O
interrupt	O
until	O
the	O
first	O
has	O
been	O
acknowledged	O
by	O
some	O
suitable	O
input/output	B-General_Concept
instruction	O
,	O
so	O
as	O
to	O
prevent	O
interrupts	O
from	O
being	O
nested	O
.	O
</s>
<s>
The	O
Algol	B-Language
compiler	B-Language
does	O
not	O
regard	O
location	O
5	O
as	O
a	O
reserved	O
location	O
,	O
although	O
this	O
may	O
have	O
more	O
to	O
do	O
with	O
the	O
unsuitability	O
of	O
Algol	B-Language
for	O
process	O
control	O
applications	O
than	O
indicating	O
that	O
interrupts	O
are	O
never	O
regarded	O
as	O
a	O
mainstream	O
facility	O
.	O
</s>
<s>
There	O
is	O
also	O
an	O
Autocode	B-Language
for	O
simple	O
programming	O
tasks	O
,	O
allowing	O
faster	O
program	O
development	O
without	O
the	O
need	O
for	O
a	O
knowledge	O
of	O
machine	O
code	O
.	O
</s>
<s>
The	O
803B	O
with	O
8192	O
words	O
of	O
memory	O
is	O
capable	O
of	O
running	O
the	O
Elliott	O
ALGOL	B-Language
compiler	B-Language
,	O
a	O
major	O
subset	O
of	O
the	O
Algol60	O
language	O
,	O
capable	O
of	O
loading	O
and	O
running	O
several	O
ALGOL	B-Language
programs	O
in	O
succession	O
.	O
</s>
<s>
The	O
803B	O
at	O
The	O
National	O
Museum	O
of	O
Computing	O
is	O
now	O
working	O
well	O
enough	O
to	O
run	O
this	O
compiler	B-Language
again	O
.	O
</s>
<s>
There	O
is	O
a	O
on	O
YouTube	O
of	O
it	O
compiling	B-Language
and	O
running	O
a	O
simple	O
program	O
.	O
</s>
<s>
Elliott	B-Device
803s	I-Device
(	O
and	O
later	O
Elliott	O
4100s	O
)	O
were	O
used	O
in	O
NCR-Elliott	O
'	O
s	O
joint	O
venture	O
"	O
Computer	O
Workshop	O
"	O
computer	O
bureau	O
.	O
</s>
<s>
RMIT	O
University	O
in	O
Melbourne	O
,	O
Australia	O
utilised	O
an	O
Elliott	B-Device
803	I-Device
Computer	O
for	O
student	O
use	O
in	O
1966	O
.	O
</s>
<s>
They	O
were	O
used	O
to	O
teach	O
Elliott	O
Autocode	B-Language
as	O
a	O
primary	O
language	O
but	O
also	O
had	O
an	O
ALGOL	B-Language
compiler	B-Language
.	O
</s>
<s>
They	O
were	O
also	O
used	O
for	O
CESIL	B-Language
coding	O
(	O
Computer	O
Education	O
In	O
Schools	O
Instructional	O
Language	O
)	O
.	O
</s>
<s>
Haydon	O
School	O
had	O
two	O
Elliot	B-Device
803B	I-Device
's	O
with	O
8192	O
words	O
of	O
core	O
until	O
the	O
early-1980s	O
,	O
one	O
being	O
used	O
for	O
spare	O
parts	O
.	O
</s>
<s>
It	O
was	O
used	O
for	O
running	O
Algol	B-Language
,	O
Autoode	O
and	O
a	O
BASIC	O
and	O
Fortran	O
compilers	B-Language
were	O
available	O
.	O
</s>
<s>
Mill	O
Hill	O
School	O
had	O
an	O
Elliott	B-Device
803	I-Device
with	O
8192	O
memory	O
in	O
the	O
1970s	O
.	O
</s>
<s>
It	O
had	O
five-track	O
paper	O
tape	O
reader	O
and	O
printer	O
but	O
no	O
other	O
I/O	B-General_Concept
devices	I-General_Concept
.	O
</s>
<s>
The	O
school	O
had	O
Elliott	B-Device
803	I-Device
autocode	B-Language
and	O
Algol	B-Language
compilers	B-Language
.	O
</s>
