<s>
The	O
RTX2010	B-Application
,	O
manufactured	O
by	O
Intersil	O
,	O
is	O
a	O
radiation	O
hardened	O
stack	B-Application
machine	I-Application
microprocessor	B-Architecture
which	O
has	O
been	O
used	O
in	O
numerous	O
spacecraft	O
.	O
</s>
<s>
It	O
is	O
a	O
two-stack	B-Application
machine	I-Application
,	O
each	O
stack	O
256	O
words	O
deep	O
,	O
that	O
supports	O
direct	O
execution	O
of	O
Forth	B-Application
.	O
</s>
<s>
Subroutine	O
calls	O
and	O
returns	O
only	O
take	O
one	O
processor	O
cycle	O
and	O
it	O
also	O
has	O
a	O
very	O
low	O
and	O
consistent	O
interrupt	B-General_Concept
latency	I-General_Concept
of	O
only	O
four	O
processor	O
cycles	O
,	O
which	O
lends	O
it	O
well	O
to	O
realtime	B-General_Concept
applications	I-General_Concept
.	O
</s>
<s>
In	O
1983	O
,	O
Chuck	O
Moore	O
implemented	O
a	O
processor	O
for	O
his	O
programming	O
language	O
Forth	B-Application
as	O
a	O
gate	O
array	O
.	O
</s>
<s>
As	O
Forth	B-Application
can	O
be	O
considered	O
a	O
dual	O
stack	O
virtual	O
machine	B-Application
,	O
he	O
made	O
the	O
processor	O
,	O
Novix	O
N4000	O
(	O
later	O
renamed	O
NC4016	O
)	O
,	O
as	O
a	O
dual-stack	O
machine	B-Application
.	O
</s>
<s>
In	O
1988	O
,	O
an	O
improved	O
processor	O
was	O
sold	O
to	O
Harris	O
Semiconductor	O
,	O
who	O
marketed	O
it	O
for	O
space	O
applications	O
as	O
the	O
RTX2000	B-Application
.	O
</s>
