<s>
FatFs	B-Device
is	O
a	O
lightweight	O
software	O
library	O
for	O
microcontrollers	O
and	O
embedded	B-Architecture
systems	I-Architecture
that	O
implements	O
FAT/exFAT	O
file	O
system	O
support	O
.	O
</s>
<s>
Written	O
on	O
pure	O
ANSI	O
C	B-Language
,	O
FatFs	B-Device
is	O
platform-independent	O
and	O
easy	O
to	O
port	O
on	O
many	O
hardware	O
platforms	O
such	O
as	O
8051	B-Architecture
,	O
PIC	B-Architecture
,	O
AVR	B-Architecture
,	O
ARM	B-Architecture
,	O
Z80	B-General_Concept
.	O
</s>
<s>
FatFs	B-Device
is	O
designed	O
as	O
thread-safe	B-Operating_System
and	O
is	O
built	O
into	O
ChibiOS	B-Operating_System
,	O
RT-Thread	B-Operating_System
,	O
and	O
Zephyr	B-Application
real-time	B-Operating_System
operating	I-Operating_System
systems	I-Operating_System
.	O
</s>
<s>
Most	O
often	O
,	O
FatFs	B-Device
is	O
used	O
in	O
low-power	O
Embedded	B-Architecture
systems	I-Architecture
where	O
memory	O
is	O
limited	O
,	O
since	O
the	O
library	O
takes	O
up	O
little	O
space	O
in	O
RAM	O
and	O
program	O
code	O
.	O
</s>
<s>
FatFs	B-Device
is	O
designed	O
to	O
be	O
a	O
Filesystem	B-Application
Layer	I-Application
that	O
is	O
agnostic	O
to	O
the	O
platform	O
and	O
storage	B-General_Concept
media	I-General_Concept
it	O
is	O
used	O
with	O
.	O
</s>
<s>
This	O
means	O
that	O
FatFs	B-Device
can	O
work	O
with	O
any	O
physical	O
device	O
such	O
as	O
an	O
SD	B-Device
card	I-Device
or	O
a	O
hard	B-Device
disk	I-Device
on	O
any	O
platform	O
that	O
can	O
run	O
plain	O
C	B-Language
code	I-Language
if	O
the	O
implementer	O
provides	O
a	O
control	O
module	O
interface	O
.	O
</s>
<s>
FatFs	B-Device
library	O
architecture	O
logically	O
separates	O
the	O
abstractions	O
of	O
the	O
user	O
app	O
and	O
the	O
platform-dependent	O
code	O
.	O
</s>
<s>
The	O
user	O
application	O
and	O
the	O
low	O
level	O
disk	O
I/O	O
layer	O
(	O
driver	B-Application
)	O
must	O
be	O
added	O
by	O
the	O
implementer	O
.	O
</s>
<s>
In	O
the	O
minimum	O
implementation	O
,	O
the	O
driver	B-Application
layer	O
must	O
support	O
at	O
least	O
these	O
3	O
interfaces	O
:	O
</s>
<s>
This	O
level	O
of	O
abstraction	O
allows	O
implementers	O
to	O
write	O
an	O
application	O
once	O
,	O
and	O
then	O
port	O
it	O
on	O
different	O
platforms	O
,	O
changing	O
only	O
the	O
implementation	O
of	O
the	O
driver	B-Application
.	O
</s>
<s>
FatFs	B-Device
has	O
its	O
own	O
minimalistic	O
license	O
similar	O
to	O
the	O
BSD	B-Operating_System
license	I-Operating_System
.	O
</s>
<s>
The	O
only	O
condition	O
is	O
to	O
keep	O
the	O
copyright	O
notice	O
in	O
case	O
of	O
redistribution	B-License
of	O
the	O
source	O
code	O
.	O
</s>
<s>
The	O
conditions	O
of	O
FatFs	B-Device
license	O
are	O
not	O
cover	O
any	O
redistributions	O
in	O
binary	O
form	O
,	O
such	O
as	O
embedded	B-Application
code	I-Application
and	O
hex	O
files	O
.	O
</s>
