<s>
ARM	B-Architecture
Instruction	I-Architecture
Set	I-Architecture
Simulator	O
,	O
also	O
known	O
as	O
ARMulator	B-Application
,	O
is	O
one	O
of	O
the	O
software	O
development	O
tools	O
provided	O
by	O
the	O
development	O
systems	O
business	O
unit	O
of	O
ARM	O
Limited	O
to	O
all	O
users	O
of	O
ARM-based	O
chips	O
.	O
</s>
<s>
Part	O
of	O
this	O
heritage	O
is	O
still	O
visible	O
in	O
the	O
provision	O
of	O
a	O
Tube	B-Device
BBC	I-Device
Micro	I-Device
model	O
in	O
ARMulator	B-Application
.	O
</s>
<s>
ARMulator	B-Application
is	O
written	O
in	O
C	B-Language
and	O
provides	O
more	O
than	O
just	O
an	O
instruction	B-Application
set	I-Application
simulator	I-Application
,	O
it	O
provides	O
a	O
virtual	O
platform	O
for	O
system	O
emulation	O
.	O
</s>
<s>
It	O
comes	O
ready	O
to	O
emulate	O
an	O
ARM	B-Architecture
processor	I-Architecture
and	O
certain	O
ARM	O
coprocessors	B-General_Concept
.	O
</s>
<s>
If	O
the	O
processor	O
is	O
part	O
of	O
an	O
embedded	B-Architecture
system	I-Architecture
,	O
then	O
licensees	O
may	O
extend	O
ARMulator	B-Application
to	O
add	O
their	O
own	O
implementations	O
of	O
the	O
additional	O
hardware	O
to	O
the	O
ARMulator	B-Application
model	O
.	O
</s>
<s>
ARMulator	B-Application
provides	O
a	O
number	O
of	O
services	O
to	O
help	O
with	O
the	O
time-based	O
behaviour	O
and	O
event	O
scheduling	O
and	O
ships	O
with	O
examples	O
of	O
memory	O
mapped	O
and	O
co-processor	B-General_Concept
expansions	O
.	O
</s>
<s>
This	O
way	O
,	O
they	O
can	O
use	O
ARMulator	B-Application
to	O
emulate	O
their	O
entire	O
embedded	B-Architecture
system	I-Architecture
.	O
</s>
<s>
A	O
key	O
limitation	O
for	O
ARMulator	B-Application
is	O
that	O
it	O
can	O
only	O
simulate	O
a	O
single	O
ARM	O
CPU	O
at	O
one	O
time	O
,	O
although	O
almost	O
all	O
ARM	O
cores	O
up	O
to	O
ARM11	O
are	O
available	O
.	O
</s>
<s>
Performance	O
of	O
ARMulator	B-Application
is	O
good	O
for	O
the	O
technology	O
employed	O
,	O
it	O
's	O
about	O
1000	O
host	O
(	O
PC	O
)	O
instructions	O
per	O
ARM	O
instruction	O
.	O
</s>
<s>
Testing	O
ARMulator	B-Application
was	O
always	O
a	O
time-consuming	O
challenge	O
,	O
the	O
full	O
ARM	B-Architecture
architecture	I-Architecture
validation	O
suites	O
being	O
employed	O
.	O
</s>
<s>
At	O
over	O
1	O
million	O
lines	O
of	O
C	B-Language
code	O
it	O
was	O
a	O
fairly	O
hefty	O
product	O
.	O
</s>
<s>
ARMulator	B-Application
allows	O
runtime	O
debugging	O
using	O
either	O
armsd	O
(	O
ARM	O
Symbolic	O
Debugger	O
)	O
,	O
or	O
either	O
of	O
the	O
graphical	O
debuggers	O
that	O
were	O
shipped	O
in	O
SDT	O
and	O
the	O
later	O
ADS	O
products	O
.	O
</s>
<s>
ARMulator	B-Application
suffered	O
from	O
being	O
an	O
invisible	O
tool	O
with	O
a	O
text	O
file	O
configuration	O
(	O
armul.conf	O
)	O
that	O
many	O
found	O
complex	O
to	O
configure	O
.	O
</s>
<s>
ARMulator	B-Application
II	O
formed	O
the	O
basis	O
for	O
the	O
high	O
accuracy	O
,	O
cycle	O
callable	O
co-verification	O
models	O
of	O
ARM	B-Architecture
processors	I-Architecture
,	O
these	O
CoVs	O
models	O
(	O
see	O
Cycle	B-Application
Accurate	I-Application
Simulator	I-Application
)	O
were	O
the	O
basis	O
of	O
many	O
CoVerification	O
systems	O
for	O
ARM	B-Architecture
processors	I-Architecture
.	O
</s>
<s>
ARMulator	B-Application
was	O
available	O
on	O
a	O
very	O
broad	O
range	O
of	O
platforms	O
through	O
its	O
life	O
,	O
including	O
Mac	B-Application
,	O
RISC	B-Operating_System
OS	I-Operating_System
platforms	O
,	O
DEC	B-Device
Alpha	I-Device
,	O
HP-UX	B-Application
,	O
Solaris	B-Application
,	O
SunOS	B-Operating_System
,	O
Windows	B-Application
,	O
Linux	B-Application
.	O
</s>
<s>
In	O
the	O
mid-1990s	O
there	O
was	O
reluctance	O
to	O
support	O
Windows	B-Application
platforms	O
;	O
pre-Windows	O
95	O
it	O
was	O
a	O
relatively	O
challenging	O
platform	O
.	O
</s>
<s>
Through	O
the	O
late	O
1990s	O
and	O
early	O
2000s	O
support	O
was	O
removed	O
for	O
all	O
but	O
Solaris	B-Application
,	O
Windows	B-Application
and	O
Linux	B-Application
-	O
although	O
undoubtedly	O
the	O
code	O
base	O
remains	O
littered	O
with	O
pragmas	O
such	O
as	O
#ifdef	O
RISCOS	B-Operating_System
.	O
</s>
<s>
ARMulator	B-Application
II	O
shipped	O
in	O
early	O
ARM	O
toolkits	O
as	O
well	O
as	O
the	O
later	O
SDT	O
2.5	O
,	O
SDT	O
2.5.1	O
,	O
ADS	O
1.0	O
,	O
ADS	O
1.1	O
,	O
ADS	O
1.2	O
,	O
RCVT	O
1.0	O
and	O
also	O
separately	O
as	O
RVISS	O
.	O
</s>
<s>
ARMulator	B-Application
has	O
been	O
gradually	O
phased	O
out	O
and	O
has	O
been	O
replaced	O
by	O
Just-in-time	O
compilation-based	O
high	O
performance	O
CPU	O
and	O
system	O
models	O
(	O
See	O
FastSim	O
link	O
below	O
)	O
.	O
</s>
<s>
ARMulator	B-Application
I	O
was	O
made	O
open	O
source	O
and	O
is	O
the	O
basis	O
for	O
the	O
GNU	O
version	O
of	O
ARMulator	B-Application
.	O
</s>
<s>
The	O
GNU	O
ARMulator	B-Application
is	O
available	O
as	O
part	O
of	O
the	O
GDB	B-Language
debugger	O
in	O
the	O
ARM	O
GNU	O
Tools	O
.	O
</s>
<s>
ARMulator	B-Application
II	O
formed	O
the	O
basis	O
for	O
the	O
high	O
accuracy	O
,	O
cycle	O
callable	O
co-verification	O
models	O
of	O
ARM	B-Architecture
processors	I-Architecture
,	O
these	O
CoVs	O
models	O
(	O
see	O
Cycle	B-Application
Accurate	I-Application
Simulator	I-Application
)	O
were	O
the	O
basis	O
of	O
many	O
CoVerification	O
systems	O
for	O
ARM	B-Architecture
processors	I-Architecture
.	O
</s>
<s>
ARMulator	B-Application
II	O
shipped	O
in	O
early	O
ARM	O
toolkits	O
as	O
well	O
as	O
the	O
later	O
SDT	O
2.5	O
,	O
SDT	O
2.5.1	O
,	O
ADS	O
1.0	O
,	O
ADS	O
1.1	O
,	O
ADS	O
1.2	O
,	O
RVCT	O
1.0	O
and	O
also	O
separately	O
as	O
RVISS	O
.	O
</s>
<s>
Key	O
contributors	O
to	O
ARMulator	B-Application
II	O
were	O
Mike	O
Williams	O
,	O
Louise	O
Jameson	O
,	O
Charles	O
Lavender	O
,	O
Donald	O
Sinclair	O
,	O
Chris	O
Lamb	O
and	O
Rebecca	O
Bryan	O
(	O
who	O
worked	O
on	O
ARMulator	B-Application
as	O
both	O
an	O
engineer	O
and	O
later	O
as	O
product	O
manager	O
)	O
.	O
</s>
<s>
A	O
key	O
contributor	O
to	O
ARMulator	B-Application
I	O
was	O
Dave	O
Jaggar	O
.	O
</s>
