<s>
The	O
High-Performance	O
Graphics	O
Display	O
Controller	O
7220	O
(	O
commonly	O
μPD7220	B-Device
or	O
NEC	B-Device
7220	I-Device
)	O
is	O
a	O
video	B-Architecture
display	I-Architecture
processor	I-Architecture
capable	O
of	O
drawing	O
lines	O
,	O
circles	O
,	O
arcs	O
,	O
and	O
character	O
graphics	O
to	O
a	O
bit-mapped	B-Algorithm
display	O
.	O
</s>
<s>
It	O
was	O
developed	O
by	O
NEC	O
in	O
order	O
to	O
support	O
the	O
Kanji	O
character	O
set	O
efficiently	O
,	O
which	O
explains	O
why	O
the	O
APC	B-Operating_System
computer	I-Operating_System
line	I-Operating_System
had	O
superior	O
graphics	O
compared	O
to	O
competing	O
models	O
.	O
</s>
<s>
The	O
chip	O
was	O
first	O
used	O
in	O
the	O
NEC	O
and	O
in	O
later	O
computers	O
,	O
such	O
as	O
the	O
NEC	B-Operating_System
PC-9801	I-Operating_System
,	O
APC	O
II	O
and	O
APC	B-Operating_System
III	I-Operating_System
,	O
the	O
NECcomputer	O
,	O
the	O
optional	O
graphics	O
module	O
for	O
the	O
DEC	O
Rainbow	O
,	O
the	O
NCR	O
Decision	O
Mate	O
V	O
,	O
the	O
Tulip	B-Device
System-1	I-Device
,	O
and	O
the	O
Epson	B-Device
QX-10	I-Device
.	O
</s>
<s>
The	O
μPD7220	B-Device
was	O
one	O
of	O
the	O
first	O
implementations	O
of	O
a	O
graphics	O
display	O
processor	O
as	O
a	O
single	O
Large	O
Scale	O
Integration	O
(	O
LSI	O
)	O
integrated	O
circuit	O
chip	O
,	O
enabling	O
the	O
design	O
of	O
low-cost	O
,	O
high-performance	O
video	O
graphics	O
cards	O
such	O
as	O
those	O
from	O
Number	O
Nine	O
Visual	O
Technology	O
.	O
</s>
<s>
It	O
was	O
first	O
used	O
in	O
the	O
NEC	O
(	O
known	O
in	O
North	O
America	O
as	O
the	O
NEC	B-Operating_System
APC	I-Operating_System
or	O
"	O
Advanced	O
Personal	O
Computer	O
"	O
)	O
in	O
1981	O
.	O
</s>
<s>
The	O
N5200	B-Operating_System
sported	O
a	O
5MHz	O
Intel	B-General_Concept
8086	I-General_Concept
processor	O
on	O
a	O
16-bit	B-Device
bus	O
,	O
and	O
came	O
with	O
a	O
text-only	O
display	O
board	O
using	O
a	O
µPD7220	O
(	O
in	O
text	O
mode	O
)	O
.	O
</s>
<s>
The	O
only	O
OS	O
on	O
the	O
original	O
NEC	B-Operating_System
APC	I-Operating_System
was	O
the	O
UCSD	B-Language
p-System	I-Language
,	O
but	O
CPM/86	B-Operating_System
support	O
was	O
added	O
in	O
1982	O
.	O
</s>
<s>
Nippon	O
Electric	O
Company	O
(	O
now	O
NEC	O
)	O
deployed	O
the	O
chip	O
in	O
other	O
computers	O
,	O
such	O
as	O
the	O
NEC	B-Operating_System
PC-9801	I-Operating_System
,	O
and	O
NEC	O
's	O
APC	O
II	O
and	O
later	O
APC	B-Operating_System
III	I-Operating_System
computers	O
,	O
and	O
also	O
released	O
it	O
to	O
other	O
manufacturers	O
in	O
Japan	O
,	O
starting	O
in	O
1982	O
.	O
</s>
<s>
While	O
most	O
computers	O
used	O
memory	O
mapped	O
character	O
,	O
or	O
bit-mapped	B-Algorithm
displays	O
,	O
those	O
with	O
a	O
µPD7220	O
had	O
access	O
to	O
a	O
,	O
for	O
the	O
time	O
,	O
sophisticated	O
graphics	O
co-processor	O
.	O
</s>
<s>
Compatibility	O
with	O
Direct	B-General_Concept
memory	I-General_Concept
access	I-General_Concept
hardware	O
made	O
it	O
possible	O
to	O
move	O
bitmaps	O
to	O
and	O
from	O
the	O
controller	O
memory	O
at	O
bus-limited	O
rates	O
.	O
</s>
<s>
It	O
included	O
a	O
light	B-Device
pen	I-Device
interface	O
that	O
synchronised	O
the	O
pixel	O
clock	O
to	O
input	O
signals	O
without	O
additional	O
processor	O
support	O
.	O
</s>
<s>
When	O
the	O
Apple	B-Device
Lisa	I-Device
was	O
announced	O
in	O
1983	O
,	O
the	O
press	O
raised	O
questions	O
on	O
why	O
the	O
popular	O
7220	O
was	O
not	O
used	O
.	O
</s>
<s>
Bruce	O
Daniels	O
pointed	O
out	O
that	O
the	O
Lisa	B-Device
primarily	O
used	O
raster	B-Algorithm
graphics	I-Algorithm
(	O
known	O
as	O
bitmap	B-Algorithm
graphics	I-Algorithm
at	O
the	O
time	O
)	O
,	O
which	O
could	O
be	O
implemented	O
with	O
less	O
expensive	O
hardware	O
support	O
.	O
</s>
<s>
IBM	O
PC	O
compatible	O
variants	O
of	O
NEC	B-Device
µPD7220	I-Device
are	O
using	O
ISA	O
bus	O
.	O
</s>
<s>
Announced	O
in	O
1982	O
,	O
it	O
was	O
the	O
first	O
of	O
what	O
would	O
become	O
a	O
long	O
line	O
of	O
Intel	B-Device
graphics	I-Device
processing	I-Device
units	I-Device
.	O
</s>
<s>
East	O
Germany	O
(	O
the	O
German	O
Democratic	O
Republic	O
)	O
produced	O
a	O
replica	O
designated	O
U82720	O
,	O
used	O
with	O
the	O
U880	B-Device
replica	O
of	O
the	O
Zilog	B-General_Concept
Z80	I-General_Concept
.	O
</s>
<s>
The	O
faster	O
complementary	B-Device
metal	I-Device
–	I-Device
oxide	I-Device
–	I-Device
semiconductor	I-Device
(	O
CMOS	B-Device
)	O
variant	O
was	O
given	O
the	O
designation	O
μPD72020	O
.	O
</s>
<s>
A	O
follow-on	O
project	O
produced	O
the	O
μPD72120	O
Advanced	O
Graphics	O
Display	O
Controller	O
(	O
AGDC	O
)	O
which	O
was	O
faster	O
and	O
supported	O
a	O
16-bit	B-Device
interface	O
.	O
</s>
