<s>
The	O
NEC	O
V20	O
is	O
a	O
microprocessor	B-Architecture
that	O
was	O
designed	O
and	O
produced	O
by	O
NEC	O
.	O
</s>
<s>
It	O
is	O
both	O
pin	O
compatible	O
and	O
object	B-General_Concept
code	I-General_Concept
compatible	I-General_Concept
with	O
the	O
Intel	B-Device
8088	I-Device
,	O
with	O
an	O
instruction	B-General_Concept
set	I-General_Concept
architecture	I-General_Concept
(	O
ISA	O
)	O
similar	O
to	O
that	O
of	O
the	O
Intel	B-Device
80188	I-Device
with	O
some	O
extensions	O
.	O
</s>
<s>
The	O
V20	O
's	O
die	O
comprised	O
63,000	O
transistors	B-Application
;	O
more	O
than	O
double	O
the	O
29,000	O
of	O
the	O
8088	B-Device
CPU	O
.	O
</s>
<s>
The	O
chip	O
was	O
designed	O
for	O
a	O
clock	O
duty	O
cycle	O
of	O
50%	O
,	O
compared	O
to	O
the	O
33%	O
duty	O
cycle	O
used	O
by	O
the	O
8088	B-Device
.	O
</s>
<s>
The	O
V20	O
has	O
two	O
,	O
16-bit	B-Device
wide	O
internal	O
databuses	O
,	O
allowing	O
two	O
data	O
transfers	O
to	O
occur	O
concurrently	O
.	O
</s>
<s>
Differences	O
like	O
that	O
meant	O
that	O
a	O
V20	O
could	O
typically	O
complete	O
more	O
instructions	O
in	O
a	O
given	O
time	O
than	O
an	O
Intel	B-Device
8088	I-Device
running	O
at	O
the	O
same	O
frequency	O
.	O
</s>
<s>
The	O
V20	O
was	O
described	O
as	O
16	B-Device
bits	I-Device
wide	O
internally	O
.	O
</s>
<s>
The	O
V20	O
was	O
reported	O
to	O
have	O
been	O
compatible	O
with	O
the	O
Intel	O
8087	O
floating-point	B-General_Concept
unit	I-General_Concept
(	O
FPU	O
)	O
coprocessor	O
.	O
</s>
<s>
The	O
V30	O
,	O
a	O
nearly	O
identical	O
CPU	O
with	O
a	O
16-bit	B-Device
wide	O
external	O
data	O
bus	O
,	O
debuted	O
on	O
March	O
1	O
,	O
1984	O
.	O
</s>
<s>
It	O
was	O
pin	O
and	O
object-code	B-General_Concept
compatible	I-General_Concept
with	O
the	O
Intel	B-General_Concept
8086	I-General_Concept
.	O
</s>
<s>
The	O
V20	O
's	O
ISA	O
includes	O
several	O
instructions	O
not	O
executed	O
by	O
the	O
8088	B-Device
,	O
with	O
instructions	O
for	O
bit	O
manipulation	O
,	O
packed	O
BCD	O
operations	O
,	O
multiplication	O
,	O
and	O
division	O
.	O
</s>
<s>
They	O
also	O
include	O
new	O
real-mode	O
instructions	O
from	O
the	O
Intel	B-General_Concept
80286	I-General_Concept
.	O
</s>
<s>
Another	O
family	O
consisted	O
of	O
the	O
TEST1	O
,	O
SET1	O
,	O
CLR1	O
,	O
and	O
NOT1	O
instructions	O
,	O
which	O
test	O
,	O
set	O
,	O
clear	O
,	O
and	O
invert	O
single	O
bits	O
of	O
their	O
operands	O
,	O
but	O
are	O
far	O
less	O
efficient	O
than	O
the	O
later	O
i80386	B-General_Concept
equivalents	O
BT	O
,	O
BTS	O
,	O
BTR	O
,	O
and	O
BTC	O
;	O
neither	O
are	O
their	O
encodings	O
compatible	O
.	O
</s>
<s>
The	O
V20	O
offered	O
a	O
mode	O
that	O
emulated	O
an	O
Intel	B-General_Concept
8080	I-General_Concept
CPU	I-General_Concept
.	O
</s>
<s>
A	O
BRKEM	O
instruction	O
is	O
issued	O
to	O
start	O
8080	B-General_Concept
emulation	O
.	O
</s>
<s>
To	O
end	O
,	O
a	O
RETEM	O
instruction	O
is	O
issued	O
in	O
8080	B-General_Concept
code	O
.	O
</s>
<s>
One	O
feature	O
not	O
often	O
employed	O
is	O
the	O
CALLN	O
(	O
call	O
native	O
)	O
which	O
issues	O
an	O
8086-type	O
interrupt	O
call	O
that	O
enables	O
x86	O
code	O
(	O
which	O
returns	O
using	O
an	O
IRET	O
)	O
to	O
be	O
mixed	O
in	O
with	O
8080	B-General_Concept
code	O
.	O
</s>
<s>
In	O
late	O
1984	O
Intel	O
again	O
filed	O
suit	O
against	O
NEC	O
,	O
claiming	O
that	O
the	O
microcode	O
in	O
the	O
V20	O
and	O
V30	O
infringed	O
its	O
patents	O
for	O
the	O
8088	B-Device
and	O
8086	B-General_Concept
processors	O
.	O
</s>
<s>
ProductPart	O
no.DetailsNEC	O
V30	O
μPD70116	O
Essentially	O
an	O
NEC	O
V20	O
with	O
a	O
16-bit	B-Device
external	O
data	O
bus	O
,	O
the	O
V30	O
was	O
pin	O
compatible	O
with	O
the	O
Intel	B-General_Concept
8086	I-General_Concept
.	O
</s>
<s>
The	O
V30	O
was	O
a	O
factory	O
upgrade	O
from	O
the	O
8086	B-General_Concept
used	O
in	O
the	O
GTD-5	B-Device
EAX	I-Device
Class	O
5	O
central	O
office	O
switch	O
.	O
</s>
<s>
It	O
was	O
also	O
used	O
in	O
the	O
Psion	B-Application
Series	I-Application
3	I-Application
,	O
the	O
NEC	O
PC-9801VM	O
,	O
the	O
Olivetti	O
PCS86	O
,	O
the	O
Applied	O
Engineering	O
"	O
PC	O
Transporter	O
"	O
card	O
for	O
the	O
Apple	B-Device
II	I-Device
series	O
of	O
computers	O
,	O
and	O
in	O
various	O
arcade	O
machines	O
(	O
particularly	O
ones	O
made	O
by	O
Irem	O
)	O
in	O
the	O
late	O
1980s	O
.	O
</s>
<s>
Years	O
later	O
,	O
a	O
low-voltage	O
V30	O
MZ	O
version	O
was	O
used	O
in	O
Bandai	O
's	O
handheld	O
WonderSwan	B-Operating_System
game	O
console	O
.	O
</s>
<s>
NEC	B-Device
V25	I-Device
µPD70320	O
A	O
microcontroller	B-Architecture
version	O
of	O
the	O
NEC	O
V20	O
.	O
</s>
<s>
NEC	O
V25HS	O
μPD79011	O
A	O
version	O
of	O
the	O
V25	B-Device
with	O
the	O
RX116	B-Operating_System
RTOS	O
in	O
the	O
internal	O
ROM	O
.	O
</s>
<s>
NEC	O
V25+	O
μPD70325	O
High-speed	O
version	O
of	O
the	O
V25	B-Device
.	O
</s>
<s>
The	O
V33	O
has	O
performance	O
equivalent	O
to	O
Intel	B-General_Concept
80286	I-General_Concept
.	O
</s>
<s>
8080	B-General_Concept
emulation	O
is	O
not	O
supported	O
.	O
</s>
<s>
NEC	O
V35	O
μPD70330	O
A	O
microcontroller	B-Architecture
version	O
of	O
the	O
NEC	O
V30	O
.	O
</s>
<s>
NEC	O
V35HS	O
μPD79021	O
A	O
version	O
of	O
the	O
V35	O
with	O
the	O
RX116	B-Operating_System
RTOS	O
in	O
the	O
internal	O
ROM	O
.	O
</s>
<s>
NEC	O
V40	O
μPD70208	O
An	O
embedded	O
version	O
of	O
the	O
V20	O
,	O
integrated	O
Intel-compatible	O
8251	B-Device
USART	O
,	O
8253	B-Device
programmable	O
interval	O
timer	O
,	O
and	O
8255	B-Device
parallel	O
port	O
interface	O
.	O
</s>
<s>
Used	O
in	O
the	O
Olivetti	O
PC1	O
,	O
Digisystems	O
Jetta	O
XD	O
,	O
the	O
Sharp	B-Device
PC-4500	I-Device
and	O
the	O
Zenith	B-Device
Eazy	I-Device
PC	I-Device
.	O
</s>
<s>
NEC	O
V41	O
μPD70270	O
Integrates	O
a	O
V30HL	O
core	O
and	O
PC-XT	B-Device
peripherals	O
:	O
8255	B-Device
parallel	O
port	O
interface	O
,	O
8254	B-Device
programmable	O
interval	O
timer	O
,	O
8259	B-Device
PIC	O
,	O
8237	B-Device
DMA	O
controller	O
and	O
8042	B-Device
keyboard	O
controller	O
.	O
</s>
<s>
NEC	O
V51	O
μPD70280	O
Integrates	O
a	O
V30HL	O
core	O
and	O
PC-XT	B-Device
peripherals	O
:	O
8255	B-Device
parallel	O
port	O
interface	O
,	O
8254	B-Device
programmable	O
interval	O
timer	O
,	O
8259	B-Device
PIC	O
,	O
8237	B-Device
DMA	O
controller	O
and	O
8042	B-Device
keyboard	O
controller	O
.	O
</s>
<s>
Was	O
used	O
in	O
the	O
Olivetti	B-Device
Quaderno	I-Device
PT-XT-20	O
.	O
</s>
<s>
NEC	O
V53	O
μPD70236	O
Integrates	O
a	O
V33	O
core	O
with	O
4-channel	O
DMA	O
(	O
μPD71087/i8237	O
)	O
,	O
UART	O
(	O
μPD71051/i8251	O
)	O
,	O
three	O
timer/counters	O
(	O
μPD71054/i8254	O
)	O
and	O
interrupt	O
controller	O
(	O
μPD71059/i8259	O
)	O
.	O
</s>
<s>
Used	O
in	O
Sharp	B-Operating_System
Zaurus	I-Operating_System
PI-B304/B308	I-Operating_System
NEC	O
V55PI	O
μPD70433	O
Vadem	B-Device
VG230	I-Device
A	O
single-chip	O
PC	O
platform	O
.	O
</s>
<s>
The	O
VG230	O
contained	O
a	O
16	O
MHz	O
NEC	O
V30HL	O
processor	O
and	O
IBM	B-Device
PC/XT	I-Device
-compatible	O
core	O
logic	O
,	O
LCD	O
controller	O
(	O
CGA/AT	O
&T640x400	O
)	O
with	O
touch-plane	O
support	O
,	O
keyboard	O
matrix	O
scanner	O
,	O
dual	O
PCMCIA	B-Architecture
2.1	O
card	O
controller	O
,	O
EMS	B-Device
4.0	O
hardware	O
support	O
for	O
up	O
to	O
64	O
MB	O
,	O
and	O
built-in	O
timer	O
,	O
PIC	O
,	O
DMA	O
,	O
UART	O
and	O
RTC	O
controllers	O
.	O
</s>
<s>
It	O
was	O
used	O
in	O
the	O
HP	B-Device
OmniGo	I-Device
100	I-Device
,	O
120	B-Device
and	O
IBM	B-Device
Simon	I-Device
.	O
</s>
<s>
Vadem	O
VG330	O
Successor	O
to	O
the	O
VG230	O
,	O
it	O
contained	O
a	O
32	O
MHz	O
NEC	O
V30MX	O
processor	O
and	O
IBM	O
PC/AT	O
-compatible	O
core	O
logic	O
with	O
dual	O
PICs	O
,	O
LCD	O
controller	O
(	O
640x480	O
)	O
,	O
keyboard	O
matrix	O
scanner	O
,	O
PC	B-Architecture
Card	I-Architecture
ExCA	O
2.1	O
controller	O
and	O
SIR	O
port	O
.	O
</s>
<s>
NEC	B-Device
V60	I-Device
μPD70616	B-Device
With	O
the	O
V60	B-Device
processor	O
,	O
NEC	O
departed	O
from	O
the	O
x86	O
design	O
and	O
launched	O
a	O
new	O
,	O
32-bit	O
CISC	B-Architecture
architecture	I-Architecture
.	O
</s>
<s>
The	O
V60	B-Device
and	O
the	O
V70	O
,	O
which	O
differed	O
mainly	O
in	O
the	O
widths	O
of	O
their	O
respective	O
external	O
address	O
and	O
data	O
busses	O
,	O
both	O
included	O
a	O
V20/V30	O
emulation	O
mode	O
.	O
</s>
