<s>
CompactRISC	B-Device
is	O
a	O
family	O
of	O
instruction	B-General_Concept
set	I-General_Concept
architectures	I-General_Concept
from	O
National	O
Semiconductor	O
.	O
</s>
<s>
The	O
architectures	O
are	O
designed	O
according	O
to	O
reduced	B-Architecture
instruction	I-Architecture
set	I-Architecture
computing	I-Architecture
principles	O
,	O
and	O
are	O
mainly	O
used	O
in	O
microcontrollers	B-Architecture
.	O
</s>
<s>
The	O
subarchitectures	O
of	O
this	O
family	O
are	O
the	O
16-bit	O
CR16	B-Device
and	O
CR16C	B-Device
and	O
the	O
32-bit	O
CRX	O
.	O
</s>
<s>
Features	O
of	O
CR16	B-Device
family	O
:	O
compact	O
implementations	O
(	O
less	O
than	O
1	O
mm2	O
with	O
250	O
nm	O
)	O
,	O
addressing	O
of	O
2MB	O
(	O
2	O
)	O
,	O
frequencies	O
up	O
to	O
66MHz	O
,	O
hardware	O
multiplier	O
for	O
16-bit	O
integers	O
.	O
</s>
<s>
CR16	B-Device
has	O
16	O
general	O
purpose	O
registers	O
of	O
16	O
bits	O
,	O
and	O
address	O
registers	O
of	O
21	O
bits	O
wide	O
.	O
</s>
<s>
CR16C	B-Device
comes	O
with	O
a	O
different	O
opcode	O
encoding	O
format	O
,	O
has	O
23	O
–	O
32-bit-wide	O
address	O
registers	O
and	O
provides	O
two	O
32-bit	O
general	O
purpose	O
registers	O
.	O
</s>
<s>
CR16	B-Device
implements	O
traps	O
and	O
interrupts	O
.	O
</s>
<s>
Implementations	O
of	O
CR16	B-Device
has	O
three-stage	O
pipeline	O
:	O
fetch	O
,	O
decode	O
,	O
execute	O
.	O
</s>
<s>
CR16	B-Device
was	O
used	O
in	O
several	O
National	O
Semiconductor	O
microcontrollers	B-Architecture
,	O
and	O
since	O
2001	O
integrated	O
microcontrollers	B-Architecture
were	O
available	O
having	O
built-in	O
flash	O
memory	O
.	O
</s>
