<s>
Sequential	B-Language
function	I-Language
chart	I-Language
(	O
SFC	O
)	O
is	O
a	O
visual	B-Language
programming	I-Language
language	I-Language
used	O
for	O
programmable	B-Architecture
logic	I-Architecture
controllers	I-Architecture
(	O
PLCs	O
)	O
.	O
</s>
<s>
The	O
SFC	O
standard	O
is	O
defined	O
as	O
Preparation	O
of	O
function	O
charts	O
for	O
control	O
systems	O
,	O
and	O
was	O
based	O
on	O
(	O
itself	O
based	O
on	O
binary	O
Petri	B-Operating_System
nets	I-Operating_System
)	O
.	O
</s>
