<s>
An	O
operating	B-Operating_System
system	I-Operating_System
abstraction	I-Operating_System
layer	I-Operating_System
(	O
OSAL	B-Operating_System
)	O
provides	O
an	O
application	B-Application
programming	I-Application
interface	I-Application
(	O
API	B-Application
)	O
to	O
an	O
abstract	B-Application
operating	B-General_Concept
system	I-General_Concept
making	O
it	O
easier	O
and	O
quicker	O
to	O
develop	O
code	O
for	O
multiple	O
software	O
or	O
hardware	B-Architecture
platforms	O
.	O
</s>
<s>
OS	O
abstraction	B-Application
layers	O
deal	O
with	O
presenting	O
an	O
abstraction	B-Application
of	O
the	O
common	O
system	O
functionality	O
that	O
is	O
offered	O
by	O
any	O
Operating	B-General_Concept
system	I-General_Concept
by	O
the	O
means	O
of	O
providing	O
meaningful	O
and	O
easy	O
to	O
use	O
Wrapper	O
functions	O
that	O
in	O
turn	O
encapsulate	O
the	O
system	O
functions	O
offered	O
by	O
the	O
OS	O
to	O
which	O
the	O
code	O
needs	O
porting	O
.	O
</s>
<s>
A	O
well	O
designed	O
OSAL	B-Operating_System
provides	O
implementations	O
of	O
an	O
API	B-Application
for	O
several	O
real-time	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
(	O
such	O
as	O
vxWorks	B-Operating_System
,	O
eCos	B-Operating_System
,	O
RTLinux	B-Application
,	O
RTEMS	B-Operating_System
)	O
.	O
</s>
<s>
Implementations	O
may	O
also	O
be	O
provided	O
for	O
non	O
real-time	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
,	O
allowing	O
the	O
abstracted	O
software	O
to	O
be	O
developed	O
and	O
tested	O
in	O
a	O
developer	O
friendly	O
desktop	O
environment	O
.	O
</s>
<s>
In	O
addition	O
to	O
the	O
OS	O
APIs	B-Application
,	O
the	O
OS	O
Abstraction	B-Application
Layer	O
project	O
may	O
also	O
provide	O
a	O
hardware	B-Operating_System
abstraction	I-Operating_System
layer	I-Operating_System
,	O
designed	O
to	O
provide	O
a	O
portable	O
interface	O
to	O
hardware	B-Architecture
devices	O
such	O
as	O
memory	O
,	O
I/O	O
ports	O
,	O
and	O
non-volatile	B-General_Concept
memory	I-General_Concept
.	O
</s>
<s>
To	O
facilitate	O
the	O
use	O
of	O
these	O
APIs	B-Application
,	O
OSALs	B-Operating_System
generally	O
include	O
a	O
directory	O
structure	O
and	O
build	B-Application
automation	I-Application
(	O
e.g.	O
,	O
set	O
of	O
makefiles	O
)	O
to	O
facilitate	O
building	O
a	O
project	O
for	O
a	O
particular	O
OS	O
and	O
hardware	B-Architecture
platform	O
.	O
</s>
<s>
Implementing	O
projects	O
using	O
OSALs	B-Operating_System
allows	O
for	O
development	O
of	O
portable	O
embedded	O
system	O
software	O
that	O
is	O
independent	O
of	O
a	O
particular	O
real-time	B-Operating_System
operating	I-Operating_System
system	I-Operating_System
.	O
</s>
<s>
MapuSoft	O
Technologies	O
-	O
provides	O
a	O
commercial	O
OS	O
Abstraction	B-Application
implementation	O
allowing	O
software	O
to	O
support	O
multiple	O
RTOS	B-Operating_System
operating	B-General_Concept
systems	I-General_Concept
.	O
</s>
<s>
ClarinoxSoftFrame	O
–	O
middleware	O
which	O
provides	O
OS	O
abstraction	B-Application
targeting	O
wireless	O
embedded	O
device	O
and	O
system	O
development	O
.	O
</s>
