<s>
MicroEmpix	B-Operating_System
is	O
the	O
microkernel	B-Operating_System
(	O
much	O
nearer	O
to	O
an	O
exokernel	B-Operating_System
)	O
version	O
of	O
Empix	O
,	O
an	O
operating	B-General_Concept
system	I-General_Concept
(	O
OS	O
)	O
developed	O
at	B-Operating_System
the	O
Computing	O
Systems	O
Laboratory	O
(	O
CSLab	O
)	O
of	O
the	O
Electrical	O
&	O
Computer	O
Engineering	O
department	O
at	B-Operating_System
the	O
National	O
Technical	O
University	O
of	O
Athens	O
.	O
</s>
<s>
Empix	O
began	O
in	O
the	O
late	O
1980	O
's	O
as	O
the	O
laboratory	O
's	O
effort	O
to	O
write	O
a	O
small	O
Unix-like	B-Operating_System
modern	O
multitasking	B-Operating_System
OS	O
,	O
intended	O
for	O
educational	O
use	O
.	O
</s>
<s>
Borrowing	O
most	O
of	O
its	O
basic	O
characteristics	O
(	O
file	B-Application
system	I-Application
,	O
binary	O
format	O
,	O
shell	B-Operating_System
)	O
from	O
other	O
popular	O
OSes	O
of	O
the	O
time	O
(	O
Xinu	B-Operating_System
,	O
Minix	B-Operating_System
,	O
DOS	B-Device
)	O
.	O
</s>
<s>
Empix	O
is	O
quite	O
small	O
(	O
about	O
10,000	O
lines	O
of	O
code	O
)	O
and	O
supports	O
Intel	B-Operating_System
x86	I-Operating_System
processors	O
,	O
in	O
the	O
IBM	B-Device
Personal	I-Device
Computers	I-Device
(	O
PC	O
)	O
XT	B-Device
(	O
8088	B-Device
)	O
,	O
and	O
AT	B-Operating_System
(	O
80286	B-General_Concept
)	O
architectures	O
,	O
floppy	B-Device
disks	I-Device
and	O
hard	B-Device
disk	I-Device
drives	I-Device
(	O
with	O
the	O
File	B-Application
Allocation	I-Application
Table	I-Application
(	O
FAT	O
)	O
16	O
limits	O
)	O
,	O
and	O
Enhanced	B-Device
Graphics	I-Device
Adapter	I-Device
(	O
EGA	B-Device
)	O
graphics	O
(	O
80x25	O
color	O
terminal	O
)	O
and	O
the	O
serial	B-Protocol
ports	I-Protocol
.	O
</s>
<s>
It	O
has	O
a	O
shell	B-Operating_System
with	O
some	O
basic	O
commands	O
,	O
and	O
the	O
ability	O
to	O
execute	O
multiple	O
processes	O
.	O
</s>
<s>
MicroEmpix	B-Operating_System
is	O
far	O
different	O
.	O
</s>
<s>
It	O
's	O
about	O
1,600	O
lines	O
of	O
code	O
(	O
over	O
which	O
about	O
1,000	O
devoted	O
to	O
serial	B-Protocol
port	I-Protocol
control	O
)	O
,	O
and	O
it	O
's	O
a	O
microkernel	B-Operating_System
,	O
meaning	O
that	O
it	O
creates	O
and	O
runs	O
processes	O
in	O
kernel-space	O
,	O
with	O
no	O
distinction	O
between	O
process-space	O
and	O
kernel	O
space	O
.	O
</s>
