<s>
UltraHLE	B-Device
is	O
a	O
discontinued	O
emulator	B-Application
for	O
the	O
Nintendo	B-Operating_System
64	I-Operating_System
.	O
</s>
<s>
Emulating	B-Application
the	O
Nintendo	B-Operating_System
64	I-Operating_System
(	O
which	O
was	O
only	O
3	O
years	O
old	O
at	O
the	O
time	O
)	O
made	O
it	O
the	O
first	O
of	O
the	O
N64	B-Operating_System
emulators	B-Application
to	O
run	O
commercial	O
titles	O
at	O
a	O
playable	O
frame	O
rate	O
on	O
the	O
hardware	O
of	O
the	O
time	O
,	O
and	O
the	O
first	O
emulator	B-Application
for	O
a	O
currently-sold	O
console	O
system	O
,	O
which	O
drew	O
Nintendo	O
to	O
seek	O
legal	O
action	O
against	O
the	O
developers	O
.	O
</s>
<s>
Earlier	O
emulators	B-Application
had	O
sought	O
to	O
accurately	O
emulate	O
all	O
low-level	O
operations	O
of	O
a	O
target	O
machine	O
;	O
this	O
worked	O
well	O
for	O
consoles	O
such	O
as	O
the	O
Super	B-Application
NES	I-Application
and	O
Genesis	B-Operating_System
that	O
were	O
substantially	O
simpler	O
than	O
the	O
computer	O
running	O
the	O
emulator	B-Application
.	O
</s>
<s>
HLE	O
was	O
done	O
even	O
before	O
the	O
UltraHLE	B-Device
emulator	B-Application
(	O
to	O
emulate	O
the	O
BIOS	O
,	O
and	O
the	O
SNES	B-Application
enhancement	O
chips	O
)	O
.	O
</s>
<s>
But	O
UltraHLE	B-Device
introduced	O
aggressive	O
optimization	O
and	O
time-savers	O
which	O
go	O
beyond	O
traditional	O
HLE	O
.	O
</s>
<s>
Co-authors	O
Epsilon	O
and	O
RealityMan	O
realized	O
that	O
since	O
N64	B-Operating_System
games	O
were	O
programmed	O
in	O
C	B-Language
,	O
they	O
could	O
intercept	O
(	O
the	O
far	O
fewer	O
)	O
C	B-Language
library	O
calls	O
rather	O
than	O
machine-level	O
operations	O
,	O
and	O
simply	O
reimplement	O
the	O
libraries	O
.	O
</s>
<s>
Thus	O
UltraHLE	B-Device
is	O
an	O
emulator	B-Application
that	O
is	O
partly	O
implemented	O
as	O
a	O
simulator	O
,	O
in	O
contrast	O
to	O
projects	O
such	O
as	O
MAME	B-Device
.	O
</s>
<s>
However	O
it	O
paved	O
the	O
way	O
for	O
playable	O
emulators	B-Application
of	O
recent	O
consoles	O
that	O
require	O
considerable	O
graphical	O
computational	O
power	O
which	O
could	O
be	O
simulated	O
easily	O
with	O
available	O
PC	O
graphic	O
cards	O
.	O
</s>
<s>
The	O
final	O
implementation	O
was	O
written	O
in	O
C	B-Language
and	O
used	O
the	O
Glide	B-Operating_System
API	I-Operating_System
,	O
specific	O
to	O
3dfx	O
adapters	O
.	O
</s>
<s>
Due	O
to	O
the	O
emulator	B-Application
's	O
popularity	O
,	O
several	O
Glide	B-Operating_System
to	O
DirectX	B-Application
translation	O
utilities	O
were	O
made	O
specifically	O
for	O
UltraHLE	B-Device
for	O
non-3dfx	O
video	O
cards	O
.	O
</s>
<s>
UltraHLE	B-Device
's	O
high-level	B-Device
emulation	I-Device
had	O
its	O
drawbacks	O
;	O
at	O
the	O
time	O
of	O
its	O
release	O
it	O
was	O
able	O
to	O
emulate	O
only	O
approximately	O
20	O
games	O
to	O
a	O
playable	O
standard	O
as	O
it	O
emulated	B-Application
and	O
simulated	O
only	O
those	O
calls	O
required	O
by	O
those	O
specific	O
games	O
;	O
it	O
was	O
necessary	O
to	O
adapt	O
the	O
emulator	B-Application
for	O
games	O
that	O
used	O
different	O
parts	O
of	O
the	O
N64	B-Operating_System
hardware	O
.	O
</s>
<s>
Nevertheless	O
it	O
supported	O
many	O
more	O
titles	O
than	O
other	O
contemporaneous	O
N64	B-Operating_System
emulation	B-Application
projects	O
such	O
as	O
Project	B-Language
Unreality	I-Language
.	O
</s>
<s>
The	O
technique	O
was	O
taken	O
over	O
by	O
the	O
Cxbx-Reloaded	O
emulator	B-Application
,	O
which	O
emulates	B-Application
the	O
Microsoft	B-Operating_System
Xbox	I-Operating_System
,	O
uses	O
HLE	O
to	O
reimplement	O
the	O
Video	O
,	O
and	O
audio	O
DSP	B-Architecture
.	O
</s>
<s>
Emulators	B-Application
other	O
than	O
UltraHLE	B-Device
eventually	O
adopted	O
variants	O
of	O
high-level	B-Device
emulation	I-Device
as	O
well	O
.	O
</s>
<s>
For	O
example	O
,	O
the	O
Dolphin	B-Application
emulator	I-Application
,	O
which	O
emulates	B-Application
the	O
GameCube	B-Application
and	O
Wii	B-Operating_System
,	O
uses	O
HLE	O
to	O
reimplement	O
the	B-Operating_System
Wii	I-Operating_System
's	O
IOS	O
operating	O
system	O
,	O
and	O
it	O
also	O
has	O
an	O
option	O
for	O
HLE	O
of	O
the	O
GameCube	B-Application
's	O
audio	O
DSP	B-Architecture
.	O
</s>
<s>
Also	O
notable	O
for	O
its	O
time	O
,	O
UltraHLE	B-Device
was	O
capable	O
of	O
playing	O
commercial	O
games	O
while	O
the	O
console	O
was	O
still	O
commercially	O
viable	O
,	O
a	O
feat	O
which	O
was	O
ultimately	O
noticed	O
by	O
Nintendo	O
.	O
</s>
<s>
In	O
February	O
1999	O
,	O
Nintendo	O
began	O
the	O
process	O
of	O
filing	O
a	O
lawsuit	O
against	O
the	O
emulator	B-Application
's	O
authors	O
,	O
along	O
with	O
the	O
website	O
hosting	O
the	O
emulator	B-Application
.	O
</s>
<s>
Despite	O
this	O
,	O
UltraHLE	B-Device
had	O
grown	O
beyond	O
either	O
its	O
authors	O
 '	O
or	O
Nintendo	O
's	O
control	O
.	O
</s>
<s>
After	O
the	O
source	O
code	O
was	O
leaked	O
in	O
2002	O
,	O
an	O
OpenGL	B-Application
version	O
of	O
UltraHLE	B-Device
called	O
UltraHLE	B-Device
2064	O
was	O
released	O
,	O
though	O
it	O
garnered	O
little	O
acclaim	O
,	O
as	O
several	O
more	O
powerful	O
emulators	B-Application
had	O
subsequently	O
been	O
released	O
.	O
</s>
<s>
UltraHLE	B-Device
2064	O
was	O
available	O
at	O
its	O
official	O
site	O
until	O
the	O
site	O
was	O
de-registered	O
.	O
</s>
