<s>
FlexRay	B-Protocol
is	O
an	O
automotive	B-Architecture
network	I-Architecture
communications	I-Architecture
protocol	I-Architecture
developed	O
by	O
the	O
FlexRay	B-Protocol
Consortium	I-Protocol
to	O
govern	O
on-board	O
automotive	O
computing	O
.	O
</s>
<s>
It	O
is	O
designed	O
to	O
be	O
faster	O
and	O
more	O
reliable	O
than	O
CAN	B-Protocol
and	O
TTP	O
,	O
but	O
it	O
is	O
also	O
more	O
expensive	O
.	O
</s>
<s>
The	O
FlexRay	B-Protocol
consortium	I-Protocol
disbanded	O
in	O
2009	O
,	O
but	O
the	O
FlexRay	B-Protocol
standard	O
is	O
now	O
a	O
set	O
of	O
ISO	O
standards	O
,	O
ISO	O
to	O
.	O
</s>
<s>
FlexRay	B-Protocol
is	O
a	O
communication	O
bus	B-General_Concept
designed	O
to	O
ensure	O
high	O
data	O
rates	O
,	O
fault	O
tolerance	O
,	O
operating	O
on	O
a	O
time	O
cycle	O
,	O
split	O
into	O
static	O
and	O
dynamic	O
segments	O
for	O
event-triggered	O
and	O
time-triggered	O
communications	O
.	O
</s>
<s>
FlexRay	B-Protocol
supports	O
data	O
rates	O
up	O
to	O
,	O
explicitly	O
supports	O
both	O
star	O
and	O
bus	B-General_Concept
physical	O
topologies	O
,	O
and	O
can	B-Protocol
have	O
two	O
independent	O
data	O
channels	O
for	O
fault-tolerance	O
(	O
communication	O
can	B-Protocol
continue	O
with	O
reduced	O
bandwidth	O
if	O
one	O
channel	O
is	O
inoperative	O
)	O
.	O
</s>
<s>
The	O
bus	B-General_Concept
operates	O
on	O
a	O
time	O
cycle	O
,	O
divided	O
into	O
two	O
parts	O
:	O
the	O
static	O
segment	O
and	O
the	O
dynamic	O
segment	O
.	O
</s>
<s>
The	O
static	O
segment	O
is	O
preallocated	O
into	O
slices	O
for	O
individual	O
communication	O
types	O
,	O
providing	O
stronger	O
determinism	O
than	O
its	O
predecessor	O
CAN	B-Protocol
.	O
</s>
<s>
The	O
dynamic	O
segment	O
operates	O
more	O
like	O
CAN	B-Protocol
,	O
with	O
nodes	O
taking	O
control	O
of	O
the	O
bus	B-General_Concept
as	O
available	O
,	O
allowing	O
event-triggered	O
behavior	O
.	O
</s>
<s>
The	O
FlexRay	B-Protocol
Consortium	I-Protocol
was	O
made	O
up	O
of	O
the	O
following	O
core	O
members	O
:	O
</s>
<s>
There	O
were	O
also	O
Premium	O
Associate	O
and	O
Associate	O
members	O
of	O
FlexRay	B-Protocol
consortium	I-Protocol
.	O
</s>
<s>
The	O
first	O
series	O
production	O
vehicle	O
with	O
FlexRay	B-Protocol
was	O
at	O
the	O
end	O
of	O
2006	O
in	O
the	O
BMW	O
X5	O
(	O
E70	O
)	O
,	O
enabling	O
a	O
new	O
and	O
fast	O
adaptive	O
damping	O
system	O
.	O
</s>
<s>
Full	O
use	O
of	O
FlexRay	B-Protocol
was	O
introduced	O
in	O
2008	O
in	O
the	O
new	O
BMW	O
7	O
Series	O
(	O
F01	O
)	O
.	O
</s>
<s>
The	O
FlexRay	B-Protocol
system	O
consists	O
of	O
a	O
bus	B-General_Concept
and	O
ECUs	O
(	O
Electronic	B-Device
control	I-Device
unit	I-Device
)	O
.	O
</s>
<s>
At	O
each	O
time	O
,	O
only	O
one	O
ECU	O
writes	O
to	O
the	O
bus	B-General_Concept
.	O
</s>
<s>
Each	O
bit	O
to	O
be	O
sent	O
is	O
held	O
on	O
the	O
bus	B-General_Concept
for	O
8	O
sample	O
clock	O
cycles	O
.	O
</s>
<s>
If	O
nothing	O
is	O
being	O
communicated	O
,	O
the	O
bus	B-General_Concept
is	O
held	O
in	O
state	O
1	O
(	O
high	O
voltage	O
)	O
,	O
so	O
every	O
receiver	O
knows	O
that	O
the	O
communication	O
started	O
when	O
the	O
voltage	O
drops	O
to	O
0	O
.	O
</s>
<s>
When	O
developing	O
and/or	O
troubleshooting	O
the	O
FlexRay	B-Protocol
bus	B-General_Concept
,	O
examination	O
of	O
hardware	O
signals	O
can	B-Protocol
be	O
very	O
important	O
.	O
</s>
<s>
Logic	O
analyzers	O
and	O
bus	B-General_Concept
analyzers	O
are	O
tools	O
which	O
collect	O
,	O
analyze	O
,	O
decode	O
,	O
store	O
signals	O
so	O
people	O
can	B-Protocol
view	O
the	O
high-speed	O
waveforms	O
at	O
their	O
leisure	O
.	O
</s>
<s>
Ethernet	O
may	O
replace	O
FlexRay	B-Protocol
for	O
bandwidth	O
intensive	O
,	O
non-safety	O
critical	O
applications	O
.	O
</s>
