Internati
o
nal
Journal of Ele
c
trical
and Computer
Engineering
(IJE
CE)
V
o
l.
5, N
o
. 5
,
O
c
tob
e
r
201
5, p
p
. 9
9
2
~
1
002
I
S
SN
: 208
8-8
7
0
8
9
92
Jo
urn
a
l
h
o
me
pa
ge
: h
ttp
://iaesjo
u
r
na
l.com/
o
n
lin
e/ind
e
x.ph
p
/
IJECE
Networking Heterogeneous Mi
crocontroller based Systems
throu
g
h Univers
a
l Seri
al Bus
Sas
t
ry
K
o
d
a
n
d
a
R
a
ma
J
a
m
m
al
am
ad
ak
a
*
, Va
lluru Sa
i
Kuma
r
Reddy
*
, Smt
J S
a
si
Bhanu
**
*
Department of Electronics
and
Computer
S
c
ien
ce Engine
ering
,
KL
Univers
i
t
y
**
Departmen
t
of
computer
Scien
ce
and
Engineering, KL University
Article Info
A
B
STRAC
T
Article histo
r
y:
Received
May 13, 2015
Rev
i
sed
Ju
l 1
,
2
015
Accepte
d
J
u
l 20, 2015
Networking heterogeneous
embedded
s
y
s
t
em
s
is
a ch
all
e
n
g
e.
Eve
r
y
distributed
embedded s
y
stems require
s that the network is designed
specifically
co
nsidering th
e
hetero
g
e
neity
that ex
its among differen
t
Microcontro
ller
based s
y
stems that ar
e used
in develop
i
ng a distributed
em
bedded s
y
s
t
em
. Comm
unication ar
chit
ectu
r
e, which con
s
iders
the
addressing of the individu
al s
y
stems,
arb
itration, s
y
nch
r
onisation, error
detection and control etc. needs to
be designed considering
a specific
application.
The
issue of configur
ing the sl
aves has to be addr
essed. It is
als
o
important that the messages, flow of
the m
e
ss
ages
acros
s
the individual ES
s
y
ste
m
s mu
st b
e
de
signe
d.
Every
dist
ribu
ted embedded sy
st
em is different
and needs to
be
dealt with
separ
a
tely
.
This
pap
e
r pres
ents
an
approa
c
h
that
addr
esses various
i
ssue
s
re
la
t
e
d to
networking distr
i
buted embedded sy
stems
through use of universal serial bus
communication
protocol (USB). The app
r
oach
h
a
s been
applied
to design a
distributed
embedded that monitors a
nd cont
rols tem
p
eratur
es within a
Nuclear
re
acto
r
s
y
s
t
em
.
Keyword:
Distributed Em
bedde
d
System
s
Het
e
r
oge
ne
ous
ES sy
st
em
s
Net
w
or
ki
n
g
E
S
Sy
st
em
s
Serial Comm
unication
USB
Copyright ©
201
5 Institut
e
o
f
Ad
vanced
Engin
eer
ing and S
c
i
e
nce.
All rights re
se
rve
d
.
Co
rresp
ond
i
ng
Autho
r
:
Sastry KR
Jam
m
a
la
m
a
daka,
Depa
rt
m
e
nt
of
El
ect
roni
cs
an
d C
o
m
put
er E
n
gi
nee
r
i
n
g,
KL Uni
v
er
sity
,
V
a
dd
esw
a
r
a
m
,
Gu
n
t
u
r
D
i
str
i
ct, An
dhr
a Pr
adesh
,
IN
DI
A 522
502
.
Em
a
il: d
r
sastry@k
l
u
n
i
v
e
rsity.in
1.
INTRODUCTION
1.
1
B
a
ck
gro
und
Em
bedded sy
s
t
em
s are bei
n
g use
d
e
x
t
e
nsi
v
el
y
fo
r m
oni
t
o
ri
n
g
a
nd c
o
nt
r
o
l
l
i
ng
vari
o
u
s p
h
y
s
i
cal
param
e
ters. Em
bedded syste
m
s are reactive that they
respond to cha
nge
s taking place in the external
en
v
i
ron
m
en
t. Alm
o
st all ele
c
tron
ic g
a
dg
ets (wh
i
ch
incl
ude digital
cameras, was
h
ing
mach
in
es…etc.) b
e
ing
u
s
ed
to
d
a
y are fitted
with
an e
m
b
e
d
d
e
d
syste
m
. E
m
b
e
d
d
e
d
syste
m
s are also
u
s
ed
th
ese d
a
ys as co
mp
u
ting
n
o
d
e
s conn
ected
o
n
to
i
n
tern
et, fo
rm
in
g
in
t
o
i
n
tern
et of th
i
n
g
s
.
Man
y
sp
ecialised
app
lication
s
su
ch
as au
to
m
o
b
ile syste
m
s req
u
i
re
in
terconn
ecting
ind
i
v
i
du
al
em
bedde
d sy
st
em
sfor co
nt
r
o
l
l
i
ng bra
k
es, d
o
o
r
s, m
i
rrors
, r
a
re and f
r
ont
o
b
ject
i
n
di
cat
or
s, engi
ne t
e
m
p
erat
ure
,
wh
eel sp
eed, tyre p
r
essure,
DVD con
t
ro
l
…
etc. and
to
pr
ov
id
e informatio
n
in
to
a
d
i
sp
lay u
n
it wh
ich
is fitted
i
n
t
o
a da
sh
bo
ard
.
The i
ndi
vi
dual
em
bedde
d sy
st
em
s are
gene
ral
l
y
het
e
r
oge
ne
ou
s i
n
n
a
t
u
re as t
h
ey
a
r
e bui
l
t
aro
u
nd di
ffe
re
nt
t
echn
o
l
o
gi
e
s
. Som
e
t
i
m
e
s t
h
e net
w
o
r
ki
ng
has t
o
be
achi
e
ved t
h
r
o
u
g
h
co
nnect
i
ng t
h
e
indivi
dual em
bedde
d
system
s
that are placed in di
fferent layers,
each layer ca
tering
for a
specific
com
m
uni
cat
i
on s
p
ee
d.
Net
w
or
ki
n
g
o
f
i
ndi
vi
d
u
al
em
bedded sy
st
em
s i
s
genera
l
l
y
achi
e
ved t
h
r
o
ug
h Se
ri
al
bus
base
d
com
m
uni
cat
i
on ar
ou
n
d
I
2
C
,
C
AN,
USB
,
R
S
4
85 et
c.
, co
m
m
uni
cat
i
on pr
ot
oc
ol
s. Eac
h
t
y
pe o
f
net
w
o
r
ki
n
g
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
088
-87
08
I
J
ECE Vo
l. 5
,
N
o
. 5
,
O
c
tob
e
r
20
15
:
992
–
1
002
99
3
leads to differe
n
t comm
unication c
h
a
r
acteris
tics such as
b
a
u
d
rate, leng
th
o
f
co
mm
u
n
i
catio
n
,
bu
s term
in
atio
n
etc.
Net
w
or
ki
n
g
o
f
het
e
r
oge
ne
ou
s em
bed
d
ed s
y
st
em
s usi
ng
any
of t
h
e seri
al
com
m
uni
cati
on
pr
ot
oc
ol
requ
ires h
a
rd
ware co
nv
ersion and
t
h
e
k
i
nd
o
f
conv
ersi
o
n
requ
ired
will be b
a
sed
on
t
h
e typ
e
o
f
techno
log
y
use
d
i
n
b
u
i
l
d
i
ng t
h
e i
n
di
vi
d
u
al
em
bedd
ed
sy
st
em
s. Every
net
w
or
ked
em
bedde
d sy
s
t
em
, t
hus
m
u
st
be
i
ndi
vi
dual
l
y
de
si
gne
d a
nd a
s
suc
h
t
h
ere
i
s
n
o
t
h
i
n
g l
i
k
e
ge
n
e
ral
ap
pr
oac
h
r
ecom
m
e
nde
d f
o
r
net
w
or
ki
n
g
a set
of
het
e
r
o
gene
ous
em
bedde
d
sy
st
em
s. M
a
ny
i
ssues
suc
h
as m
a
st
er and
sal
v
e a
d
dr
essi
ng
,
desi
g
n
i
ng t
h
e
m
e
ssages t
h
at
fl
o
w
acr
oss, t
h
e seque
nce
of
fl
o
w
o
f
m
e
ssages ha
ve t
o
be
consi
d
ere
d
f
o
r b
u
i
l
d
i
n
g di
st
r
i
but
e
d
em
bedde
d sy
st
em
s. These i
ssues di
f
f
er i
n
m
a
ny
way
s
from
one di
st
ri
b
u
t
e
d em
bedde
d sy
st
em
t
o
ot
her
.
A
sy
st
em
of wo
r
k
i
n
g /
A
p
p
r
oa
ch i
s
nee
d
e
d
t
h
at
hel
p
de
vel
opi
ng a
di
st
ri
b
u
t
e
d em
bedde
d sy
st
em
for a speci
f
i
c
ap
p
lication
con
s
id
ering
th
e issu
es
wh
ich
i
n
clu
d
e
h
e
te
r
o
ge
nei
t
y
, m
e
ssage fl
o
w
,
n
ode
ad
dressi
n
g
, a
n
d
m
e
ssage
desi
g
n
.
1.
2
Probl
em
De
fi
ni
ti
on
A
di
st
ri
b
u
t
e
d
em
bedde
d
sy
st
em
i
nvol
ves
u
s
e o
f
i
n
di
vi
du
al
m
i
croco
n
t
r
o
l
l
e
r base
d sy
st
em
s. Each
micro
c
on
tro
ller system
may
h
a
v
e
bu
ilt-in
i
n
terfaces us
ing wh
ich
co
mm
u
n
icatio
n
with
oth
e
r m
i
cro
c
on
tro
llers
can be achi
e
ve
d. Est
a
bl
i
s
hi
n
g
com
m
uni
cati
on am
ong vari
o
u
s m
i
croco
n
t
r
ol
l
e
r base
d sy
st
em
s i
s
essent
i
a
l
t
o
im
pl
em
ent
a di
st
ri
but
ed
em
bedde
d a
p
pl
i
cat
i
on.
I
n
a
di
st
ri
b
u
t
e
d em
bed
d
e
d
a
ppl
i
cat
i
o
n
b
o
t
h
t
h
e
har
d
wa
re a
n
d
soft
ware that
com
p
rise e
n
tire application is di
st
ri
b
u
t
e
d. C
o
m
m
uni
cat
i
on i
s
n
ecessary
am
o
ng t
h
e
m
i
croco
n
t
r
ol
l
e
r
based
sy
st
em
s f
o
r
exc
h
a
ngi
ng
o
f
pr
ocess
i
n
f
o
rm
at
i
on.
Net
w
or
ki
n
g
o
f
di
ffe
rent
m
i
cr
oco
n
t
r
ol
l
e
r bas
e
d
sy
st
em
s requi
res ad
dres
si
ng
vari
ous
Ha
rd
ware a
n
d
soft
ware related heteroge
ne
ous
iss
u
es whic
h
incl
ude
s
in
te
rfaces
, protoc
ols, im
ple
m
en
tation of prot
ocols
etc.
N
e
two
r
k
i
ng
o
f
e
m
b
e
d
d
ed
syste
m
s can
b
e
ach
i
ev
ed
in
m
a
n
y
w
a
ys u
s
ing
p
r
o
t
o
c
o
l
s su
ch as RS23
2
C
, RS485,
RS42
2,
SP
I,
f
i
re wire,
U
S
B, CA
N, I
2
C
,
ETHER
NET,
PC
I,
a
nd ES
A
et
c.
Am
ong al
l
,
bus base
d
seri
al
com
m
uni
cat
i
on p
r
ot
oc
ol
s ar
e used
f
o
r est
a
bl
i
s
hi
n
g
a n
e
t
w
o
r
k c
o
nne
ct
i
ng al
l
t
h
e i
n
di
vi
d
u
al
m
i
croc
ont
rol
l
e
r
sy
st
em
s. USB
i
s
suc
h
a
p
r
ot
o
c
ol
w
h
i
c
h i
s
fr
eque
nt
l
y
use
d
by
t
h
e
i
n
dust
r
y
f
o
r
ef
fect
i
n
g
c
o
m
m
uni
cat
i
on
am
on
g
i
ndi
vi
dual
m
i
croco
n
t
r
ol
l
e
r
bas
e
d sy
st
em
s.
One
o
f
t
h
e m
a
jo
r
pr
o
b
l
e
m
s
i
n
i
m
pl
em
ent
i
ng
U
S
B
ba
sed
sy
st
em
i
s
due
t
o
l
ack
o
f
nat
i
ve s
u
p
p
o
rt
with
in
so
m
e
o
f
th
e micro
c
ontro
ller syste
m
s. Th
e USB
imp
l
em
en
tatio
n
s
with
in
so
m
e
o
f
th
e micro
c
ontro
ller
syste
m
s d
e
fer a lo
t, as USB ex
ists in
sev
e
ral
v
e
rsion
s
and
th
e ex
isten
ce
o
f
sev
e
ral i
m
p
l
emen
tatio
n
v
a
ri
atio
n
s
.
Thi
s
i
s
l
eadi
n
g t
o
est
a
bl
i
s
hi
ng i
n
t
e
rfaci
ng
usi
n
g m
a
ny
of t
h
e co
n
v
ersi
on
de
vi
ces w
h
i
c
h l
eads t
o
f
r
e
que
nt
pr
ot
oc
ol
c
o
n
v
e
rsi
o
n.
Spee
d
of
com
m
uni
cat
i
on i
s
no
rm
al
l
y
affect
ed
whe
n
se
ve
ral
versi
o
n
s
o
f
t
h
e sam
e
pr
ot
oc
ol
i
s
use
d
whi
c
h al
s
o
s
h
o
u
l
d
be
ad
d
r
e
ssed.
Every
di
st
ri
b
u
t
ed em
bedde
d
sy
st
em
requi
res
di
ffe
re
nt
c
o
m
m
uni
cat
i
on sy
st
em
archi
t
ect
ures a
n
d
every
com
m
uni
cat
i
on sy
st
e
m
m
u
st
be cust
om
i
s
ed for i
m
pl
em
ent
a
t
i
on of sp
eci
fi
c d
i
st
ri
but
ed em
bedde
d
App
licatio
n.
No
g
e
neric co
mm
u
n
i
catio
n
syste
m
as su
ch
will m
e
e
t
th
e
p
u
rp
o
s
es
o
f
all typ
e
s of
d
i
st
ribu
ted
sy
st
em
s.Thus t
h
ere
i
s
a re
q
u
i
r
em
ent
of
fi
n
d
i
n
g
ap
pr
oac
h
es,
m
echani
s
m
s
and
m
e
t
hods
usi
n
g
w
h
i
c
h
U
S
B
base
d
com
m
uni
cat
i
on i
s
used wi
t
h
i
n
t
h
e net
w
or
k o
f
het
e
r
o
gene
o
u
s em
bedde
d sy
st
em
s and al
so t
o
desi
g
n
appl
i
cat
i
o
n sp
eci
fi
c com
m
uni
cat
i
on sy
st
em
archi
t
ect
ure a
nd t
h
e desi
gni
ng
of t
h
e sam
e
consi
d
eri
ng
vari
o
u
s
aspects of communication whic
h includ
e
addressing, c
o
nfiguration, t
r
an
sm
ission, reception, arbitrati
on,
syn
c
hron
isation
,
error
d
e
tectio
n and
con
t
ro
l
etc.
The m
e
ssages
m
u
st
fl
ow
i
n
a se
que
nce
f
o
r
ef
fect
i
n
g
a
di
st
ri
b
u
t
e
d a
p
pl
i
cat
i
on.
The
USB
base
d
syste
m
d
o
e
s no
t supp
ort prioritisatio
n
of the slav
es to
re
sp
ond
even
t
h
ou
gh
all th
e slav
es are allo
tted with
an
ad
dress. Th
ere m
u
st b
e
a way o
f
p
r
i
o
ritising
th
e req
u
e
sts
an
d respo
n
s
es
as p
e
r th
e app
l
icatio
n
requ
iremen
ts
in
itiated
fro
m
th
e m
a
ster and respo
n
d
e
d
b
y
slav
es. Th
e
d
a
ta p
a
ck
ets m
u
st also
b
e
d
e
si
gn
ed co
n
s
i
d
eri
n
g
t
h
e
way the
data is
exc
h
ange
d am
ong t
h
e m
a
sters and t
h
e salve
s
.
1.3 Related
Wor
k
M
a
ny
co
nt
ri
b
u
t
i
ons
have
bee
n
prese
n
t
e
d
re
l
a
t
e
d t
o
t
h
e
pr
obl
em
area;
m
o
st
o
f
t
h
em
conce
n
t
r
at
e
d
aro
u
nd i
m
pl
em
ent
a
t
i
on o
f
USB
ba
sed se
ri
al
com
m
uni
cat
i
on m
e
t
hod
t
o
be
used a
s
a st
anda
rd
w
h
i
c
h i
s
gene
rally achi
e
ved through c
o
nve
r
ting
from one interface
to the
othe
r. So
m
e
work
has
bee
n
prese
n
ted tha
t
expl
ai
n
t
h
e
wa
y
t
h
e U
S
B
pr
ot
ocol
ca
n
be
co
nve
rt
ed
i
n
t
o
ot
her
p
r
ot
ocol
s
.
M
o
st
o
f
t
h
e c
o
nt
ri
b
u
t
i
o
ns a
r
e
i
n
t
h
e
area of p
o
i
n
t
-
t
o
-
p
oi
nt
c
o
m
m
u
n
i
cat
i
on usi
n
g
USB
.
An
a Lu
iza
d
e
Alm
e
id
a Perei
r
a Zuqu
im
et. al.
,
[1
]
u
s
ed a con
v
e
rter to
t
r
an
sform
RS2
3
2
C
o
u
t
p
u
t/inp
u
t
t
o
USB
eq
ui
va
l
e
nt
. The desi
g
n
of t
h
e c
o
n
v
e
r
t
e
r i
s
prese
n
t
e
d base
d o
n
En
get
r
a
on
UPS S
e
ri
al
com
m
unicat
i
o
n
req
u
i
r
em
ent
s
and
t
h
ey
have
s
h
o
w
n t
h
e
i
m
plem
ent
a
t
i
on
on
C
y
press m
i
cro
c
ont
rol
l
e
r
base
d sy
st
em
.
Every
hom
e, t
h
ese
day
s
i
s
b
e
i
ng a
u
t
o
m
a
t
e
d by
usi
n
g
va
ri
o
u
s el
ect
ro
ni
c gad
g
et
s
fo
r
m
i
ng i
n
t
o
a
di
gi
t
a
l
net
w
o
r
k
.
Eve
n
t
h
e m
obi
l
e
pho
nes are
bei
n
g use
d
f
o
r
aut
o
m
a
t
i
ng an
d com
m
uni
cat
ing
pu
rp
oses
. H
o
m
e
s
are
bei
n
g c
o
n
n
ect
ed b
o
t
h
t
h
r
o
u
g
h
wi
re
d a
n
d
wi
rel
e
ss
br
o
a
dba
n
d
. M
a
ny
st
an
dar
d
s
ha
v
e
bee
n
dev
e
l
o
ped
f
o
r
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
ECE
I
S
SN
:
208
8-8
7
0
8
N
e
t
w
orki
ng
He
t
e
roge
ne
ous
M
i
croco
n
t
r
ol
l
e
r
bas
ed
Syst
e
m
s
t
h
ro
u
g
h
…
(Sastry KR Ja
mma
lam
ada
ka
)
99
4
affect
i
n
g di
gi
t
i
zat
i
on an
d co
m
m
uni
cat
i
on b
u
t
not
m
a
ny
appl
i
e
d f
o
r real
l
i
f
e appl
i
cat
i
o
n
s
. St
anda
r
d
pr
ot
oc
ol
s
are t
o
be
deve
l
ope
d t
h
at
sui
t
s com
p
l
e
t
e
ly
the i
ssue
of
ho
m
e
di
gi
t
i
zat
i
o
n.
Yo
n
g
-Se
o
k
Ki
m
et
. al
., [2
]
have
devel
ope
d
h
o
m
e net
w
or
k
us
i
ng
USB
as a
s
t
anda
rd
.
It
i
s
p
o
ssi
bl
e t
o
e
x
pa
nd
t
h
e
h
o
m
e
net
w
o
r
k
w
h
e
n
t
h
e sam
e
i
s
devel
ope
d t
h
r
o
ug
h U
S
B
p
r
ot
ocol
.
W
hi
l
e
t
h
e de
vi
ces i
n
st
al
l
e
d i
n
t
h
e h
o
m
e are i
n
t
e
rfac
e
d t
h
r
o
u
gh
US
B
,
t
h
e
m
obi
l
e
co
m
m
u
n
i
cat
i
on i
s
ac
hi
eved
t
h
r
o
ug
h
C
D
M
A
a
n
d
the local comm
unication is
ac
hi
eved through
W
i
-Fi.
They
pri
m
ari
l
y
f
o
cuss
ed
i
n
pr
ot
oc
ol
co
n
v
ersi
on
f
r
om
USB
t
o
C
D
M
A
a
n
d
vi
ce ve
rsa.
Uni
v
ersal
Seri
al
B
u
s (
U
SB
) i
s
bei
ng
use
d
as
de
faul
t
i
n
d
u
st
r
y
st
anda
rd
f
o
r
pr
ocessi
ng
i
n
p
u
t
dat
a
t
h
at
get
ge
nerat
e
d
cont
i
n
u
o
u
s
l
y
. The
use
of
US
B
and
USB
H
U
B
cau
ses cer
t
a
i
n
am
ount
o
f
l
a
t
e
nci
e
s m
a
k
i
ng i
t
uns
uitable for
accessing t
h
e data which is ge
nerate
d at rapi
d spee
ds.
It ha
s been
proved t
h
at USB ca
n be use
d
whe
n
t
h
e
real
t
i
m
e
requi
rem
e
nt
s are
so
ft
.
U
S
B
p
r
ot
ocol
ca
n
be
used
i
n
re
spect
of t
h
e
de
vi
ces t
h
at
ca
n t
o
l
e
rat
e
t
h
e del
a
y
i
n
t
h
e or
der
of m
i
l
liseco
nds
[3]
.
T
h
i
s
pa
per
h
a
s limited
its d
i
scu
ssio
n
with
referen
ce t
o
th
e laten
c
ies
wi
t
h
whi
c
h on
e
can w
o
r
k
usi
n
g
U
S
B
.
M
a
ny
com
m
u
n
i
cat
i
on p
r
ot
o
c
ol
s are bei
n
g
used f
o
r affec
t
i
ng com
m
uni
cat
i
on bet
w
ee
n t
h
e de
vi
ces,
sy
st
em
s and c
ont
rol
e
qui
pm
ent
.
St
a
nda
rd
pr
ot
oc
ol
s
bei
n
g
used
i
n
cl
u
d
e
suc
h
as
USB
,
R
S
2
32C
, C
A
N, a
n
d
ETHER
NET.
In m
o
st
of t
h
e adva
nce
d
s
y
st
em
s, t
h
e prot
ocol
s are
b
e
i
ng
used i
n
t
e
r- m
i
xi
ngl
y
for t
h
e
d
e
v
e
l
o
p
m
en
t of in
teg
r
ated
ci
rcu
its.
Ho
wever it h
a
s
b
ecome ev
id
en
t that a real-tim
e o
p
e
rating
syst
e
m
an
d
adva
nce
d
m
i
cr
oco
n
t
r
ol
l
e
r bas
e
d sy
st
em
s are t
o
be use
d
w
h
en suc
h
m
a
ny
pr
ot
oc
ol
s are t
o
be u
s
ed
wi
t
h
i
n
t
h
e
sam
e
board
.
Tag
h
i
M
oham
a
di
et
. al
., [
4
]
have
pre
s
ent
e
d t
h
at
i
m
pl
ement
i
n
g
,
co
nt
r
o
l
l
i
ng an
d
dat
a
acqui
si
t
i
o
n
fun
c
tion
s
throug
h
em
b
e
dd
ed
syste
m
s will h
e
l
p
in
ach
i
ev
i
n
g
o
v
e
rall reliab
ility an
d
du
rab
i
l
ity. Th
ere is a
n
e
ed
to
d
e
term
in
e h
a
rdware arch
itectu
r
e and
real ti
m
e
m
u
lti-
tas
k
ing
p
r
o
cesses wh
en m
u
ltip
l
e
pro
t
o
c
o
l
s are to
be
use
d
.
Suc
h
a
s
y
ste
m
can be
conve
n
iently e
m
ployed wh
e
n
network
interfaces with different protocol layers
are to
be used. The a
r
chit
ect
u
r
e can al
s
o
be
em
pl
oy
ed f
o
r c
onst
r
uct
i
n
g a s
m
art
gat
e
way
or a
r
out
er
. H
o
weve
r
an em
bedde
d
board
whic
h is
versatile ha
ving all the stat
e
d
interfaces is re
qui
red
for e
s
tablishing suc
h
kind
of
hy
b
r
i
d
net
w
o
r
k w
h
i
c
h use
s
di
ffe
re
nt
ki
n
d
s
of p
r
ot
ocol
s.
In t
h
i
s
case a m
i
ddl
eware i
s
req
u
i
r
e
d
usi
n
g
whi
c
h
com
m
uni
cat
i
on wi
t
h
al
l
st
an
dar
d
pr
ot
oc
ol
s
can be
car
ri
ed.
Here a
g
ai
n
p
r
ot
oc
ol
co
n
v
ers
i
on
base
d o
n
t
h
e real
-
t
i
m
e
operat
i
n
g
sy
st
em
has bee
n
onl
y
di
scus
se
d.
Diffe
re
nt sens
ors
are
norm
ally connected to a m
i
cro
c
on
tro
ller
b
a
sed
sy
ste
m
eith
er th
ro
ugh
u
s
ing
I
2
C
/
SPI
di
rect
i
n
t
e
rfac
e
or
usi
n
g a
n
al
o
g
s
i
gnal
s
c
o
nve
rt
ed t
o
di
gi
t
a
l
si
gnal
s
usi
n
g a
n
A t
o
D
co
n
v
ert
e
r
.
Micro
c
on
tro
ller
b
a
sed
systems can
b
e
co
nn
ected
to bo
th a
lo
cal ho
st
o
r
t
o
a rem
o
te ho
st th
ro
ugh
an
i
n
tern
et
con
n
ect
i
o
n est
a
bl
i
s
he
d t
h
ro
u
g
h
U
S
B
p
o
r
t
s
[
5
]
.
U
S
B
’
s
are t
hus
bei
n
g u
s
ed
as H
u
bs,
co
n
n
ect
i
ng
devi
ces
on
o
n
e
si
de an
d h
o
st
s
on t
h
e ot
her l
e
adi
n
g t
o
est
a
bl
i
s
hm
ent
of b
o
t
h
l
o
cal
area a
n
d wi
de area
ne
t
w
o
r
ks
. A
net
w
o
r
ki
n
g
archi
t
ect
u
r
e i
n
t
h
i
s
m
a
nner ca
n be i
m
pl
em
ent
e
d, t
h
o
u
gh B
u
s based
net
w
or
ki
n
g
i
s
not
use
d
.
A
m
i
croco
n
t
r
ol
l
e
r
base
d sy
st
em
can be
desi
g
n
e
d f
o
r c
o
m
m
u
n
i
cat
i
ng
wi
t
h
m
a
ny
of t
h
e
devi
ces
by
im
pl
em
ent
i
ng di
f
f
ere
n
t
p
r
o
t
o
c
o
l
s within
th
e sam
e
b
o
a
rd
.
Howev
e
r th
is k
i
nd
of to
po
log
y
is limited
co
n
s
id
erin
g
th
e ex
tendib
ility
req
u
i
r
em
ent
s
of di
st
ri
b
u
t
e
d e
m
bedded sy
st
em
s;
onl
y
fi
xed
num
ber of em
bed
d
e
d
b
o
ar
ds
can be co
nnec
t
ed i
n
t
h
i
s
way
.
The
net
w
or
ki
n
g
i
n
t
h
i
s
case i
s
el
abo
r
at
ed c
onsi
d
eri
n
g al
l
t
hose devi
ces t
h
at
h
a
ve bee
n
su
pp
ort
e
d
with USB
i
n
terface.
C
o
n
n
ect
i
v
i
t
y
b
e
t
w
een t
w
o
di
ffe
rent
devi
ces
t
h
at
ha
ve t
w
o
di
ff
ere
n
t
p
r
ot
ocol
i
n
t
e
rface
s
can
not
be
achi
e
ve
d
wi
t
h
out
t
h
e s
u
pp
or
t
of
a
USB
-
W
i
-Fi
b
r
i
d
ge. C
o
m
m
uni
cat
i
on i
s
af
fect
ed t
h
ro
u
g
h
co
n
v
ert
i
n
g
o
n
e
pr
ot
oc
ol
t
o
ot
h
e
r. C
o
nve
rt
ers
of t
h
i
s
ki
n
d
can be u
s
ed
fo
r devel
opi
ng
hy
bri
d
net
w
or
ks
[6]
.
T
u
sha
r
Sa
want
et
.
al., [7
]
h
a
v
e
p
r
esen
ted
a m
i
cro
c
on
tro
ller b
a
sed
system
th
at h
a
s bu
ilt-in
USB p
o
rts and
t
h
e sam
e
is in
te
rfaced
wi
t
h
t
o
uc
h scr
een
whi
c
h ha
s
but
t
o
ns t
h
r
o
ug
h w
h
i
c
h com
m
a
nd
s can
be
fe
d f
o
r ef
fect
i
n
g
dat
a
t
r
an
sfe
r
b
e
t
w
een
t
h
e m
a
ss st
ora
g
e
devi
ces
usi
n
g
U
S
B
p
o
r
t
s
sup
p
o
rt
e
d
on
th
e sam
e
b
o
a
rd. Th
is, in a
way is called
as
USB to
USB
bri
dge
de
vi
ce.
A.
Yi
n
g
H
u
a
n
g et
. al
.,
[8]
h
a
ve de
si
g
n
ed a
m
i
croco
n
t
r
ol
l
e
r base
d
USB
Host
sy
st
em
whi
c
h ca
n be
use
d
fo
r i
n
t
e
rf
aci
ng di
f
f
e
r
ent
ki
nds
of U
S
B
based de
vi
ces
. They
have
us
ed an 8
-
bi
t
M
C
UAT
8
9
C
5
5 and a
n
interface chi
p
SL811HS
for
a
c
hieving t
h
e
USB im
ple
m
entation
with
in
a
single em
bedded system
. The
MCU
is u
s
ed
t
o
m
a
k
e
it b
e
h
a
v
e
like a
USB
h
o
st.
Th
e
d
r
i
v
er/co
n
tro
ller
fun
c
tion is im
p
l
e
m
en
te
d
with
in th
e
MCU.
C
o
m
m
uni
cat
i
o
n
bet
w
ee
n a
U
S
B
de
vi
ce a
n
d
an
USB
i
m
pl
em
ent
e
d M
C
U i
s
u
n
d
e
rt
ake
n
a
s
pe
r t
h
e
st
an
d
a
rd
o
f
USB a
nd t
h
e
data flow is
us
ed to
direct the trans
f
er
ac
ross the m
a
ss stora
g
e
devices
as per t
h
e format and
stru
cture. Th
is
a is a
k
i
nd
o
f
po
in
t to po
in
t
commu
n
i
cati
o
n
syste
m
th
an
ju
st
sim
p
ly v
i
su
ali
s
in
g as a
n
e
twork
of
em
bedde
d sy
st
em
s.
Uni
v
ersal seri
al bus storage
devices are
use
d
fo
r fast
e
r
I/
/
O
ha
n
d
l
i
n
g an
d ge
neral
l
y
t
r
eat
ed as
peri
phe
ral
de
vi
ces whi
c
h n
e
e
d
s a h
o
st
f
o
r c
o
m
m
uni
cat
i
ng wi
t
h
i
t
.
C
o
m
m
uni
cat
i
o
n bet
w
een t
w
o U
S
B
devi
ces
t
hus
needs t
o
be achi
e
ved t
h
ro
u
gh a h
o
st
.
To av
oi
d t
h
e u
s
e of PC
f
o
r e
f
fect
i
ng c
o
m
m
u
n
i
cat
i
on
bet
w
e
e
n t
w
o
USB
devi
ces t
h
ere i
s
a
nee
d
t
o
i
m
pl
em
ent
a M
C
U ba
sed
USB
c
o
m
m
unicat
i
on sy
st
em
. Suc
h
ki
n
d
o
f
a
h
o
st
can
b
e
u
s
ed
as a n
e
two
r
k
hub. Th
e
p
r
o
t
o
c
o
l
n
eed
ed
to
sen
s
e ex
isten
ce
o
f
U
S
B d
e
v
i
ce is
i
m
p
l
e
m
en
ted
by th
e
MCU base
d host. Ha
rpreetet
al., [9]
have
presente
d a m
i
c
r
o
c
on
tro
ller
b
a
sed
system
to
tran
sfer
d
a
ta b
e
tween
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
088
-87
08
I
J
ECE Vo
l. 5
,
N
o
. 5
,
O
c
tob
e
r
20
15
:
992
–
1
002
99
5
t
h
e
t
w
o USB
d
e
vi
ces. I
n
t
h
i
s
sy
st
em
VDI
P2
m
odul
e
i
s
use
d
al
on
g wi
t
h
t
h
e m
i
croco
n
t
r
o
l
l
e
r. VD
IP
2 co
nsi
s
t
s
o
f
a ch
ip
called
VNC
1
L
wh
i
c
h
h
a
s bu
ilt in
USB po
rts, LC
D, and
a k
e
yp
ad
. Co
mm
an
d
s
are issu
ed
throu
g
h
a
key
b
o
ar
d e
ffec
t
i
ng
dat
a
t
r
a
n
sf
er
bet
w
ee
n t
h
e
m
a
ss st
ora
g
e
devices that a
r
e
connected
to
t
w
o of
the USB
po
r
t
s
of V
D
I
P2
. Use
r
s can see t
h
e dat
a
fl
owi
n
g across
bot
h t
h
e USB
de
vi
ces.
As suc
h
, m
odi
fi
cat
i
ons are re
qui
re
d
t
o
t
h
i
s
pr
o
p
o
s
i
t
i
on s
o
t
h
at
m
o
re USB
devi
ce
s are su
p
p
o
r
t
e
d an
d com
m
un
i
cat
i
on bet
w
ee
n any
t
w
o de
vi
ces i
s
achi
e
ve
d.
Thi
s
app
r
oach
i
s
m
o
re
or l
i
k
e
i
m
pl
em
ent
i
ng a
US
B
base
d
hu
b.
Yassi
ne
B
o
ut
e
rraet
. al
.
,
[1
0]
have
p
r
ese
n
t
e
d
a di
st
ri
bute
d
a
r
chitecture for
im
ple
m
enting an
industrial
robo
t u
s
i
n
g
m
u
ltip
le MCU’s wh
ich
are conn
ected
t
h
rou
gh a I
2
C bu
s and con
t
ro
lling
in
i
tiated
th
ro
ugh
a PC
connected to
one of
the MC
U’s t
h
rough a
USB interface. Dave
[11]
ha
s
prese
n
ted im
ple
m
entation de
tails of
USB
b
a
sed
h
u
b
f
o
r c
o
nd
uct
i
ng ei
t
h
e
r
hi
g
h
spee
d/
l
o
w s
p
e
e
d t
r
a
n
sact
i
o
ns
. D
oga
n
Ib
rahi
m
[12]
ha
s p
r
e
s
ent
e
d
com
p
l
e
t
e
descri
pt
i
o
n o
f
t
h
e
net
w
or
ki
n
g
o
f
di
st
ri
but
e
d
e
m
bedded sy
st
em
s t
h
ro
u
gh
USB
pr
ot
oc
ol
s. T
h
e
archi
t
ect
u
r
e an
d desi
g
n
o
f
a U
S
B
hu
b an
d t
h
e USB
pr
ot
oc
o
l
descri
pt
i
o
ns/
s
peci
fi
cat
i
o
n
s
h
a
ve bee
n
ext
e
n
s
i
v
el
y
prese
n
t
e
d
.
In
literature,
th
e issu
e
of
estab
lish
i
ng
an
USB b
a
sed n
e
two
r
k
conn
ectin
g a h
e
t
e
rog
e
n
e
ou
s
m
i
croco
n
t
r
ol
l
e
r base
d sy
st
em
s has n
o
t
been
qui
t
e
ad
dres
se
d. T
h
e comm
u
n
ication arc
h
itecture as suc
h
has to
be desi
gn
ed s
e
parat
e
l
y
co
ns
i
d
eri
n
g a s
p
ec
i
f
i
c
di
st
ri
b
u
t
e
d
em
bedde
d a
p
pl
i
cat
i
on. T
h
e
desi
g
n
o
f
s
p
eci
fi
c
com
m
uni
cat
i
on sy
st
em
s i
nvol
ves
al
l
o
cat
i
on
o
f
s
p
eci
fi
c
ad
dresses
t
o
t
h
e sl
aves
suc
h
t
h
at
c
o
m
m
u
n
i
cat
i
o
n
takes place as
per t
h
e priorities require
d
by the dist
ri
bute
d
em
bedde
d a
pplication.The
configurati
on
of t
h
e
slaves is also
very m
u
ch de
pende
n
t on a
specific di
stri
buted system
.
There is a
ne
ed to
design s
p
ecial
descri
ptors
usi
n
g which the
slaves a
r
e c
o
nfigure
d
as
pe
r t
h
e
requirem
ents of the
distri
bute
d
system
.
1.
4
Sol
u
ti
on
Th
us, t
h
i
s
pa
per a
d
dresse
d
t
h
e desi
g
n
o
f
USB
base
d
net
w
or
k f
o
r
con
n
ect
i
n
g h
e
t
e
ro
gene
o
u
s
M
i
croco
n
t
r
ol
l
e
r
based
sy
st
e
m
, desi
gn
o
f
speci
fi
c c
o
m
m
uni
cat
i
o
n sy
st
em
as re
qui
re
d
by
t
h
e
di
st
r
i
but
ed
em
bedde
d a
p
p
l
i
cat
i
on, ad
dre
ss al
l
o
cat
i
on t
o
t
h
e sal
v
e
s
and c
o
nfi
g
u
r
i
n
g
t
h
e sl
aves t
h
r
o
u
g
h
desc
ri
pt
o
r
s f
o
r
m
a
ki
ng
t
h
em
adapt
a
bl
e f
o
r t
h
e i
m
pl
em
ent
a
t
i
on
of
di
st
ri
b
u
t
e
d
em
bedde
d a
ppl
i
cat
i
o
n.
The
desi
gni
ng
o
f
t
h
e
messag
e
s and
co
n
t
ro
lling
th
e flo
w
of m
e
ssa
g
e
s acro
ss th
e
d
i
stribu
ted
Micro
c
on
tro
ller
based
system h
a
s b
een
prese
n
ted considering a
dist
ributed em
bedded system
th
at
m
o
n
ito
rs an
d con
t
ro
ls tem
p
eratu
r
es
with
in
a
Nuclea
r rea
c
to
r sy
stem
.
2.
METHODS
2.1
Specification Descripti
o
n of
Distrib
u
te
d E
m
bedded
App
lication
Monitoring the te
m
p
eratures
within
the nuclear reactor t
ube
s is one of the
m
o
st im
p
o
rta
n
t issues
whe
n
i
t
com
e
s t
o
u
r
ani
u
m
enri
c
h
m
e
nt
. Sens
ors a
r
e m
ount
e
d
o
n
t
o
t
h
e n
u
cl
ear
rea
c
t
o
r t
u
bes
whi
c
h are
distantly situated. Many temperat
ures
at various points
with
in each
of the Nuclear reactor tubes m
u
st be
sen
s
ed
and
it i
s
also
n
ecessary to
m
a
in
tain
p
r
op
er gr
ad
ients acro
ss v
a
riou
s po
in
ts at wh
ich
th
e tem
p
eratu
r
es
are m
easured.
Whe
n
t
e
m
p
erat
ures rai
s
es a
b
ove s
o
m
e
pre-
defi
ned l
e
vel
s
,
cool
a
n
t
s
ha
ve
t
o
be i
n
ject
ed i
n
t
o
t
h
e
tu
b
e
s to
br
ing th
e tem
p
er
atu
r
e dow
n.
Pum
p
s are u
s
ed fo
r inj
ectin
g th
e coo
l
an
ts in
to th
e tubes. Th
e
te
m
p
eratu
r
e sen
s
ing
and
im
p
l
e
m
en
tin
g
th
e
actu
a
tin
g m
e
c
h
an
ism
s
th
at co
n
t
ro
ls th
e
pro
cess of
pu
m
p
in
g is
achi
e
ve
d t
h
r
o
u
g
h
va
ri
o
u
s
em
bed
d
e
d
sy
stems. T
h
e
operat
ors m
u
st be
aler
ted whe
n
t
h
e t
e
m
p
erature
gra
d
ients
goe
s
bey
o
n
d
u
n
co
nt
r
o
l
l
a
bl
e l
e
vel
s
t
h
r
o
u
g
h
assert
i
n
g a
b
u
z
zer a
n
d
l
i
g
ht
i
n
g a
pat
t
e
r
n
o
f
LEDs
as t
h
e ca
se m
a
y
be.
A
hi
st
ori
cal
d
a
t
a
base
of t
e
m
p
erat
ures
sens
ed,
p
u
m
p
i
ng l
e
vel
s
i
m
pl
em
ent
e
d,
t
e
m
p
erat
ure
g
ra
di
ent
s
,
status of tri
g
ge
ring buzzer etc
., is cr
eated at
a PC(HOST
)
for
providing the
historical evi
d
ence
s. Eac
h
part of
sensi
n
g an
d a
c
t
u
at
i
ng re
q
u
i
r
es a ki
nd o
f
r
e
sp
onse t
i
m
e
and t
h
e
r
ef
o
r
e need
s t
o
be sense
d
, m
oni
t
o
re
d an
d
cont
rol
l
e
d
i
n
di
vi
d
u
al
l
y
t
h
r
o
u
g
h
a se
parat
e
em
bedde
d
sy
s
t
e
m
.
T
h
e
r
e is
a n
e
ed
for
co
ord
i
n
a
ting
th
e fun
c
tio
ns
bet
w
ee
n t
h
e i
n
di
vi
d
u
al
em
bedde
d
sy
st
em
s f
o
r
achi
e
vi
n
g
t
h
e sensi
n
g
a
n
d
act
uat
i
n
g
i
n
re
al
t
i
m
e
. Thi
s
l
eads t
o
t
h
e nee
d
f
o
r i
n
t
e
rco
nnect
i
n
g t
h
e i
n
di
vi
d
u
al
em
bedde
d sy
st
em
s t
h
at
hel
p
i
n
est
a
bl
i
s
hi
ng
t
h
e com
m
uni
cat
i
on
bet
w
ee
n t
h
e e
m
bedded sy
st
e
m
s whi
c
h are i
ndi
vi
d
u
al
l
y
res
p
o
n
si
bl
e fo
r ei
t
h
er se
nsi
n
g
,
ac
t
u
at
i
ng
or m
o
n
i
t
o
ri
n
g
the process ta
king
place
withi
n
the
Nuclear reactor system
.
Desi
g
n
i
n
g,
de
vel
o
pm
ent
and
im
pl
em
ent
i
n
g
t
h
e
Net
w
or
ki
ng
o
f
em
bed
d
e
d sy
st
em
s becom
e
s one
of
th
e m
o
st cru
c
ial issu
es
wh
en
it
co
m
e
s to
i
m
p
l
e
m
en
t th
e distributed em
bedded system
s. One of the m
a
jor i
ssue
t
h
at
m
u
st
be a
d
d
r
esse
d i
s
het
e
ro
ge
nei
t
y
t
h
at
exi
s
t
s
am
ong
di
ffe
re
nt
t
y
pes
of
M
i
cr
oco
n
t
r
ol
l
e
r
based
sy
s
t
em
s
whi
c
h are use
d
for
devel
opi
n
g
an
d im
pl
em
ent
i
ng a di
st
ri
bu
t
e
d em
bedde
d
sy
st
em
.These r
e
qui
rem
e
nt
s l
e
ads t
o
im
ple
m
entatio
n of distribut
e
d em
bedde
d syste
m
ha
ving se
ve
ral
microc
ontroller
base
d syste
m
s, each
d
e
sign
ated
to
m
o
n
ito
r and co
n
t
ro
l eith
er th
e sen
s
ing o
r
actu
a
tin
g
m
ech
an
ism
s
with
th
e n
e
ed fo
r th
e
cent
r
al
i
s
ed c
o
o
r
di
nat
i
on
bet
w
een t
h
e
di
st
ri
b
u
t
e
d em
bedde
d
sy
st
em
s. Fi
gur
e 1 i
s
t
h
e bl
ock
di
agram
t
h
at
sho
w
s
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
ECE
I
S
SN
:
208
8-8
7
0
8
N
e
t
w
orki
ng
He
t
e
roge
ne
ous
M
i
croco
n
t
r
ol
l
e
r
bas
ed
Syst
e
m
s
t
h
ro
u
g
h
…
(Sastry KR Ja
mma
lam
ada
ka
)
99
6
in
d
i
v
i
d
u
a
l
h
e
terog
e
n
e
ou
s emb
e
dd
ed
syste
m
s
m
ean
t fo
r
eith
er sensing
or actu
a
ti
n
g
with
bu
ilt-in
in
terfaces
al
on
g
wi
t
h
a
n
i
ndi
vi
d
u
al
em
bedde
d
sy
st
em
that
p
r
ovi
des ce
nt
ral
i
s
ed c
o
or
d
i
nat
i
on.
Fi
gu
re 1.
To
p vi
ew o
f
a Di
st
r
i
but
ed
em
bedd
ed
sy
st
em
Som
e
of t
h
e m
a
jo
r
re
qui
rem
e
nt
s t
h
at
m
u
st
b
e
m
e
t
by
t
h
e d
i
st
ri
but
ed
em
bedde
d
ap
pl
i
cat
i
ons
are
ci
t
e
d i
n
t
h
e
Table 1
Tabl
e
1. R
e
q
u
i
r
em
ent
speci
fi
cat
i
on
of
a
di
st
ri
but
e
d
em
bed
d
e
d
a
ppl
i
cat
i
o
n
Req.
Nu
m
.
Require
m
e
nt d
e
scription
1.
Read Te
m
p
-1 and
write to
LCD
2.
E
ffectUSB based co
m
m
unication between the 89C51 (
S
y
s
tem
-
1)
and the C
e
ntr
a
l M
i
cr
ocontr
o
ller
(
S
y
s
te
m
-
5)
3.
Read-
T
e
m
p
-
1 and
send to Centr
a
l Micr
o Contr
o
ller
4.
Read T
e
m
p
-
1
and
m
e
asur
e thr
oughp
ut
Te
m
p
e
r
ature-1
m
u
st be sensed at leas
t 10 ti
m
e
s per
m
illi
second
5.
E
ffect USB based
co
m
m
unication between the PI
C18F4550 (
S
y
s
tem
-
3) and the Centr
a
l M
i
cr
ocontr
o
ller
(
S
y
s
tem
-
5)
If
Te
m
p
-1
> Ref
e
r
e
n
ce Te
m
p
-1
th
en
Pu
m
p
-1
m
u
st b
e
o
n
If
Te
m
p
-1
< Ref
e
r
e
n
ce Te
m
p
-1
th
en
Pu
m
p
-1
m
u
st b
e
o
f
f
Co
m
p
ar
e Tem
p
-
1
> tem
p
-
2
and if tr
ue asser
t
buzzer
on
6.
Read Te
m
p
-1 and
m
a
ke buzzer
of
f
if <
Te
m
p
-2
If
Te
m
p
-1 > t
e
m
p
-2
then Buzzer is o
n
Response tim
e
of T
e
m
p
-
1
m
u
st be 1
0
µ Seconds
If
Te
m
p
-1
> Ref
e
r
e
n
ce Te
m
p
-1
th
en
Pu
m
p
-1
m
u
st b
e
o
n
If
Te
m
p
-1
> Ref
e
r
e
n
ce Te
m
p
-1
th
en
Pu
m
p
-1
m
u
st b
e
o
f
f
If
Te
m
p
-1 > Ref
e
r
e
nce Te
m
p
-1 then
Buzzer is on
7.
Response between the Reading the Te
m
p
-1 and stopping
the Buzzer
m
u
st 1
0
µ Seconds
If
Te
m
p
-1 > Ref
e
r
e
nce
Te
m
p
-1 then
buzzer of
f
8.
Read Te
m
p
-2 and
write to
LCD
9.
E
ffectUSB based co
m
m
unication between the AT
89S52 (
S
y
s
te
m
-
2) and the Centr
a
l Micr
o
Contr
o
ller
(
S
y
s
tem
-
5)
10.
Read-
T
e
m
p
-
2 and
send to Centr
a
l Micr
ocontr
o
ller
11.
Read T
e
m
p
-
2
and
m
e
asur
e thr
oughp
ut
E
ffect USB based
co
m
m
unication between the ATm
e
ga328 (
S
y
s
tem
-
4
)
an
d the Centr
a
l
M
i
crocontr
o
ller
(
S
y
s
tem
-
5)
12.
Read T
e
m
p
-
2
and
m
a
ke pu
m
p
-
2
on if T
e
m
p
-
2
> Reference T
e
m
p
-
2
If
Te
m
p
-2
> Ref
e
r
e
n
ce Te
m
p
-2
Pu
mp
-2
o
n
13.
Read T
e
m
p
-
2
and
m
a
ke pu
m
p
-
2
off if T
e
m
p
-
2
< Reference T
e
m
p
-
2
If
Te
m
p
-2
< Ref
e
r
e
n
ce Te
m
p
-2
Pu
mp
-2
o
f
f
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
088
-87
08
I
J
ECE Vo
l. 5
,
N
o
. 5
,
O
c
tob
e
r
20
15
:
992
–
1
002
99
7
Req.
Nu
m
.
Require
m
e
nt d
e
scription
14.
Read Te
m
p
-2 and
m
a
ke buzzer
on if
> Te
m
p
-1
If
Te
m
p
-2 > t
e
m
p
-1 Buzzer
On
15.
Read Te
m
p
-2 and
m
a
ke buzzer
of
f
if <
Te
m
p
-1
If
Te
m
p
-2 > T
e
m
p
-1 Buzzer
On
16.
Response between the Reading the T
e
m
p
-
2
and star
ting the pu
m
p
-
1
m
u
st b
e
10µ Secs
If
Te
m
p
-2
> Ref
e
r
e
n
ce Te
m
p
-2
Pu
mp
-2
On
17.
Response between the Reading the T
e
m
p
-
2
and stopping
the pu
m
p
-
2
m
u
st
be 10µ Secs
If
Te
m
p
-2
> Ref
e
r
e
n
ce Te
m
p
-2
Pu
mp
-2
Of
f
18.
The response betw
een the Reading the Te
m
p
-2
and start
i
ng the Buzzer
m
u
st be 10µ Secs
19.
If
Te
m
p
-2 > Ref
e
r
e
nce Te
m
p
-2 Buzz
er on
20.
The response betw
een the Reading the Te
m
p
-1
and stopping the Buzzer
m
u
st be 10µ Secs
If
Te
m
p
-2
> Ref
e
r
e
n
ce Te
m
p
-2
Bu
zz
er o
f
f
2.
1.
Desi
gni
n
g
U
S
B
B
a
sed
Ne
t
w
orki
ng
f
o
r
Interc
onnec
t
i
n
g
Heter
o
gen
e
ous
Indi
vi
du
al
E
m
be
dded
Sys
t
ems
USB
base
d net
w
o
r
ki
n
g
i
s
o
n
e
of
t
h
e m
e
t
hod
s t
h
at
exi
s
t
s
t
o
day
f
o
r a
c
hi
e
v
i
n
g
i
n
t
e
rc
o
nnec
t
i
on am
on
g
di
ffe
re
nt
em
bedde
d sy
st
em
s. USB
as s
u
c
h
i
s
bei
n
g
use
d
u
n
i
v
e
r
sal
l
y
and
has
becom
e
i
ndust
r
y
st
an
dar
d
f
o
r
effect
i
n
g com
m
uni
cat
i
on bet
w
een t
h
e C
o
m
put
i
n
g st
at
i
o
ns
and
peri
phe
ra
l
devi
ces an
d
no
w e
v
en
bei
n
g use
d
fo
r est
a
bl
i
s
hi
n
g
t
h
e c
o
m
m
uni
cat
i
on bet
w
ee
n m
a
ny
em
bedde
d sy
st
em
s.M
a
ny
of
t
h
e
M
i
croco
n
t
r
ol
l
e
r bas
e
d
sy
st
em
s have
no
n
a
t
i
v
e s
u
pp
ort
f
o
r
USB
w
h
i
l
e
som
e
ha
ve
. M
o
st
o
f
t
h
e
M
i
croco
n
t
r
ol
l
e
r
base
d sy
st
em
di
f
f
er
s
in
m
a
n
y
w
a
ys
(
w
o
r
d
bou
ndar
y
, end
i
an, byte ad
d
r
essi
ng, p
a
r
ity, wor
d
len
g
t
h, nu
m
b
er
of
r
e
g
i
ster
s etc.)
.
Net
w
or
ki
n
g
s
u
ch
het
e
r
oge
ne
o
u
s em
bed
d
ed
s
y
st
em
s t
h
ro
ug
h a c
h
al
l
e
n
g
e a
n
d
m
a
ny
i
nno
v
a
t
i
v
e ap
pr
oac
h
es are
r
e
qu
ir
ed
f
o
r
est
a
b
lish
i
ng
t
h
e
netw
or
k
i
n
g
of
t
h
e sam
e
.
USB
hel
p
s i
n
est
a
bl
i
s
hi
n
g
a net
w
or
k i
n
t
e
rc
on
nect
i
n
g m
a
ny
em
bedde
d sy
st
em
s. Every
di
st
ri
but
e
d
em
bedde
d
sy
st
em
i
s
di
ffe
rent
an
d a
de
di
cat
ed
net
w
or
k
ha
s t
o
be
desi
g
n
e
d a
n
d
de
vel
o
ped
.
T
h
e E
S
n
e
t
w
o
r
k
desi
g
n
m
u
st
add
r
ess a
p
pl
i
cat
i
on s
p
eci
fi
c re
qui
rem
e
nt
s.
Th
e app
licatio
n
sp
ecific requ
ire
m
en
ts related to
th
e
Nuclea
r reactor application a
r
e shown in t
h
e Table
1.
In the network,
a speci
fic em
bedde
d system
m
u
st
b
e
h
a
v
e
lik
e a
cen
tral m
i
cro
c
o
n
t
ro
ller system
wh
ich
is typ
i
cally situ
ated
at a rem
o
te lo
catio
n
.
As per th
e
d
e
scri
p
tio
n
of
th
e fu
n
c
tion
a
l
requ
irem
en
ts, th
e cen
t
r
al mic
r
o
c
on
tro
ller
b
a
sed
system
sh
allh
av
e to
act
lik
e a
master and t
h
e
rest as slaves
. The c
o
mm
unication
betwee
n the m
a
ster and the sla
v
e re
quires a s
p
ee
d
of
40
Kb
ps
w
h
i
c
h al
l
o
ws
t
h
e si
gnal
s
t
o
be
d
r
i
v
e
n
t
o
a
di
st
ance
of
m
o
re t
h
an
1K
M
whi
c
h i
s
a s
u
f
f
i
c
i
e
nt
re
qui
r
e
m
e
nt
consideri
ng t
h
e application i
n
view.
If
bus length
has to be increase
d
bi
a
s
ed-s
plit term
ination m
e
thod
has to
b
e
fo
llowed
wh
ile
estab
lish
i
ng
th
e n
e
two
r
k
.
Th
e h
i
gh
er
level n
e
two
r
k
showing
th
e co
nnectiv
ity b
e
tween
the
di
st
ri
b
u
t
e
d em
bed
d
e
d
sy
st
em
s usi
n
g
USB
as a bac
k
bo
ne
i
s
sh
ow
n i
n
Fi
gu
re
2.
The
USB
base
d
n
e
t
w
o
r
k
contains a single
m
a
ster and
4 slaves. C
o
nve
rsion m
echan
ism
s
are to be conside
r
ed
w
h
e
n
t
h
e m
i
crocont
r
o
l
l
e
r
base
d sy
st
em
s
whi
c
h are
use
d
as a pa
rt
o
f
ne
t
w
o
r
k a
r
e
het
e
r
oge
ne
ou
s d
u
e t
o
t
h
e
reas
on
t
h
at
t
h
ey
do
n
o
t
have
native USB
i
n
terface.
As
p
e
r th
e
functio
n
a
l requ
iremen
ts o
f
an app
licati
o
n
,
LPC
2
148
a
32
Bit Micro
c
on
tro
llers
u
s
ed as
a
m
a
st
er devi
ce fo
r achi
e
vi
n
g
com
m
uni
cat
i
on bet
w
ee
n t
h
e
sl
ave devi
ces
and t
h
e m
a
st
er.It
co
nsi
s
t
s
o
f
nat
i
v
e
USB support. The m
a
ster de
vice
m
u
st also
be designe
d
to alert local user through
triggering a Buzzer about
the variations taking place with
t
h
e
tem
p
erature
gra
d
ie
nts.
The
m
a
ste
r
system
m
u
st also
be
desi
gned for
in
terfaci
n
g
with
a PC for co
mm
u
n
i
catin
g
with
it fo
r ob
ta
in
i
n
g
th
e
referen
c
e te
m
p
eratu
r
es
an
d
tran
sm
itt
in
g
th
e
pr
ocess
dat
a
t
o
be
st
ore
d
i
n
a
dat
a
base
.
4 sl
a
v
e m
i
croco
n
t
r
ol
l
e
r
ba
sed
de
vi
ces
whi
c
h i
n
cl
u
d
e
8
9
C
5
1,
A
T
89
S5
2,
P
I
C
1
8
F
4
5
5
0
an
d
ATm
e
ga32
8
h
a
ve
been
co
ns
i
d
ere
d
f
o
r
i
m
p
l
em
ent
i
ng va
ri
ous
f
u
nct
i
ons
t
h
at
are
pr
o
j
ec
t
e
d as re
q
u
i
r
e
m
ent
s
whi
c
h i
n
cl
ude
sensi
n
g t
e
m
p
erat
ure
-
1, se
ns
i
ng t
e
m
p
erat
ur
e-2
,
st
art
i
n
g a
nd
st
o
ppi
ng
p
u
m
p
-1, st
a
r
t
i
n
g an
d
st
op
pi
n
g
p
u
m
p
-
2
.
In t
hose
sl
ave sy
st
em
s 89C
5
1
a
n
d AT
8
9
S
52
do
n
’
t
hav
e
t
h
e USB
su
p
p
o
r
t
.
F
o
r
i
n
t
e
rco
n
n
ect
i
n
g t
h
ese sy
st
em
s, co
nve
rsi
o
n
m
echani
s
m
s
ar
e req
u
i
r
e
d
. 8
9
C
51 a
nd
AT
89
S5
2ha
ve
been
desi
g
n
e
d
with inbuilt RS232C c
o
mm
u
n
ication interfaces, A de
vi
ce
FT232R ha
s been
use
d
for
conve
r
ting RS232C
si
gnal
s
t
o
US
B
and Vi
ce
V
e
rsa. T
h
e de
vi
ces im
pl
em
ents bu
ffe
ri
n
g
t
echni
que
s f
o
r c
o
nve
rt
i
n
g a 1
9
.
2
K
b
ps
spee
d which is the m
a
xim
u
m
speed
achie
vable t
h
rough a RS232C se
rial
com
m
uni
cat
i
on sy
st
em
int
o
t
o
1.
5M
b
p
s spee
d
whi
c
h i
s
a l
o
w
speed s
u
p
p
o
rt
on t
h
e
USB
si
d
e
. Thi
s
co
nve
rs
i
on i
s
go
o
d
en
ou
g
h
as t
h
e am
ou
nt
o
f
d
a
ta t
o
b
e
tran
sm
it
ted
from
th
e salv
e
sid
e
is
no
t m
o
re th
at 18K
b
y
tes con
s
id
ering
t
h
at th
e t
h
rou
g
h
p
u
t
for
sen
s
ing
an
d
tran
sm
issio
n
is n
o
t
m
o
re th
an 9
K
tem
p
eratures/second
wh
ich
is m
o
re th
an
sufficien
t for th
e
appl
i
cat
i
o
n t
o
be i
m
pl
em
ent
e
d. T
h
e de
si
g
n
i
ng
of t
h
e U
S
B
net
w
o
r
k co
nsi
d
e
r
i
n
g t
h
e i
n
t
e
rfaci
ng i
s
s
u
es i
s
sho
w
n i
n
t
h
e
F
i
gu
re
2.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
ECE
I
S
SN
:
208
8-8
7
0
8
N
e
t
w
orki
ng
He
t
e
roge
ne
ous
M
i
croco
n
t
r
ol
l
e
r
bas
ed
Syst
e
m
s
t
h
ro
u
g
h
…
(Sastry KR Ja
mma
lam
ada
ka
)
99
8
Figure 2.
USB base
d Networki
ng for Nuclear
reactor
system
2
.
3 D
e
sig
n
i
n
g
Communicat
i
on
Sy
st
em
The net
w
o
r
ki
n
g
di
ag
ram
shown i
n
t
h
e Fi
g
u
r
e 2 sh
ow
s t
h
e
i
n
t
e
rfaci
n
g
of
t
h
e vari
ous
het
e
ro
ge
neo
u
s
m
i
croco
n
t
r
ol
l
e
rs ba
sed sy
st
e
m
s whi
c
h are
i
n
t
e
rco
n
n
ect
ed
t
h
r
o
u
g
h
a U
S
B
based
p
r
ot
o
c
ol
sy
st
em
. Howe
ve
r
com
m
uni
cat
i
on so
ft
ware re
si
dent
i
n
di
f
f
e
rent
m
i
crocont
r
o
l
l
e
r base
d
sy
st
em
i
s
requi
red f
o
r ac
hi
evi
n
g
appl
i
cat
i
o
n s
p
e
c
i
f
i
c
m
e
ssagi
ng re
q
u
i
r
em
ent
s
usi
n
g t
h
e
net
w
or
k
desi
g
n
e
d
f
o
r t
h
e
p
u
r
pos
e.
The
com
m
uni
cat
i
on
h
a
s to b
e
in
itiated
b
y
t
h
e m
a
st
er b
y
u
s
i
n
g RTR (Rem
o
t
e tran
sm
issio
n
req
u
est) fo
r wan
t
of Tem
p
eratu
r
e-1
an
d
Tem
p
er
atu
r
e-2 to
b
e
tr
an
sm
it
ted
b
y
89
c5
1
an
d AT89
s5
2 in
th
at
sequ
en
ce. Th
e thro
ughp
u
t
, seq
u
e
n
c
ing
an
d
t
i
m
i
ng o
f
re
ce
i
p
t
of t
h
e t
e
m
p
erat
ures a
r
e
desi
g
n
e
d
an
d
devel
ope
d i
n
t
o
m
a
st
er devi
ce
. The a
p
pl
i
cat
ions
o
n
89c
51 and AT
89s
52 will have softwa
re com
ponents to re
ceive the m
a
ster re
quests a
n
d transm
it the
data t
o
t
h
e m
a
st
er dev
i
ce. The
com
m
uni
cat
i
on co
m
ponent
s i
m
pl
em
ent
s
R
S
2
3
2
C
seri
al
com
m
uni
cat
i
o
n sy
st
e
m
for
transm
itting a
n
d
receiving t
h
e
te
m
p
erature
data.
The m
a
ster de
vice at the
start-up
receives
the refe
re
nce te
m
p
eratures from
PC which is
connecte
d
to
the m
a
ster through RS232C
serial
comm
unication system
.
The se
nse
d
te
m
p
eratures are
com
p
ared
with the
referen
c
e tem
p
eratu
r
es an
d in th
e ev
en
t th
at
th
e sen
s
ed
temperat
ures
are
m
o
re than the
refe
rence
tem
p
erature
a m
e
ssage i
s
sent
t
o
t
h
e M
i
cro
c
ont
rol
l
e
r
base
d sy
st
em
s t
h
at
ope
rat
e
s t
h
e
p
u
m
ps t
o
be
on
o
r
o
f
f
.
On t
h
e m
a
st
er
side, t
w
o individual s
o
ftware
com
pone
nt
s
for eac
h
of the
pum
p
controller syst
em
shall have t
o
be i
n
place
for
t
r
ansm
i
ssi
on o
f
t
h
e com
m
and
s
and
rece
pt
i
o
n
of ac
kn
o
w
l
e
d
g
em
ent
t
h
at
t
h
e i
n
t
e
nde
d
pu
m
p
operat
i
o
n h
a
s bee
n
achi
e
ve
d s
u
cc
essful
l
y
or
ot
her
w
i
s
e.
The
com
m
uni
cat
i
on i
n
t
h
i
s
case
i
s
achi
e
ved
t
h
r
o
ug
h
use
of
USB
i
n
t
e
rface
. The
soft
ware c
o
m
pone
nt
s t
h
at
are
desi
g
n
ed f
o
r effect
i
n
g t
h
e c
o
m
m
uni
cat
i
on bet
w
ee
n t
h
e m
a
st
er
and t
h
e
pum
p cont
rol
sl
ave d
e
vi
ces i
s
achi
e
ved t
h
ro
u
gh i
m
pl
em
ent
a
t
i
on of t
h
e USB
p
r
ot
oc
ol
.T
he m
a
st
er al
so
i
s
pr
ovi
de
d wi
t
h
a c
o
m
pone
nt
t
h
at
com
put
es
t
h
e t
e
m
p
erat
ur
e gra
d
i
e
nt
a
n
d
assert
s a
buzze
r o
r
ot
he
rwi
s
e
i
f
t
h
e
te
m
p
erature gradient is beyond the
p
r
escrib
ed
li
m
i
ts. Th
is fu
n
c
tion
as
suc
h
req
u
i
r
es
no c
o
m
m
uni
cat
i
on as t
h
e
en
tire fun
c
tion
i
n
g
is im
p
l
e
m
e
n
ted
with
in th
e m
a
ster d
e
v
i
ce.
Two comm
unication com
p
onents that can c
o
mm
unicat
e using
USB with the m
a
ster a
r
e provide
d
wi
t
h
i
n
t
h
e ap
pl
i
cat
i
ons resi
de
nt
o
n
P
I
C
1
8F
4
5
5
0
a
n
d ATm
e
ga3
2
8
t
h
at
c
o
n
t
rol
s
t
h
e
r
u
n
n
i
ng
o
f
t
h
e
p
u
m
p
s f
o
r
regu
latin
g
t
h
e
flow of coo
l
ants in
to
th
e
reacto
r tub
e
s.
The soft
ware
a
r
chit
ecture
th
at
depicts the applic
ation
speci
fi
c c
o
m
m
uni
cat
i
o
n i
s
s
h
ow
n i
n
t
h
e
Fi
g
u
re
3
.
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
088
-87
08
I
J
ECE Vo
l. 5
,
N
o
. 5
,
O
c
tob
e
r
20
15
:
992
–
1
002
99
9
Fi
gu
re
3.
Sy
st
em
Archi
t
ect
ure
f
o
r e
ffect
i
n
g
c
o
m
m
uni
cat
i
on
am
ong
di
st
ri
bu
t
e
d em
bedde
d
sy
st
em
s
2
.
4
A
N
ov
el Address A
llo
cat
i
o
n
A
l
go
rit
h
m
In
USB
b
a
sed co
mm
u
n
i
catio
n
,
on
e of th
e
co
nn
ected d
e
vices will b
e
the m
a
s
t
er and
th
e
o
t
h
e
rs as
slav
es.
Ev
ery
co
mm
u
n
i
catio
n
is in
itiated
fro
m
th
e m
a
ste
r
. Ev
ery slav
e is assign
ed with
an
add
r
ess b
y
th
e
master at enumeration sta
g
e
at the tim
e when a
n
y devi
ce i
s
interfaced wi
th the
bus.Whe
n
a
de
vice is
pl
ugge
d
in
to
a USB
b
u
s, it b
eco
m
e
s
k
nown
to
t
h
e h
o
s
t thro
ugh
a process called Enum
eration.
After t
h
e proc
ess
of
enum
erat
i
on, t
h
e h
o
st
sen
d
s
a reset
si
gnal
t
o
t
h
e de
vi
ce t
h
ro
u
gh a
d
d
r
ess
0
f
o
r pl
aci
ng t
h
e de
vi
ce i
n
a kn
o
w
n
state. Th
e d
e
v
i
ce will sen
d
its d
e
tails to
th
e h
o
s
t thr
oug
h
ad
dress0
. Th
e
h
o
s
t assi
g
n
s
a
u
n
i
q
u
e
add
r
ess to
th
e
device and se
nds a reset address request to the de
vice.
After th
e requ
est is co
m
p
leted
,
th
e d
e
v
i
ce assu
m
e
s th
e
n
e
w addr
ess.
In
t
h
e case
o
f
U
S
B co
mm
u
n
icatio
n
on
ly o
n
e
slav
e
d
e
v
i
ce w
ill respond
wh
en
requ
ested
b
y
t
h
e
m
a
st
er. The
re
spo
n
se
f
r
om
t
h
e sal
v
e c
o
ul
d
be a
n
ac
k
n
o
w
l
e
dgm
ent
f
o
l
l
o
wed
by
t
h
e act
ual
dat
a
re
que
s
t
ed by
t
h
e m
a
st
er t
h
ro
ug
h a
dat
a
pac
k
et
w
h
i
c
h c
ont
ai
ns t
h
e
det
a
ils of th
e d
a
ta th
e m
a
ster
i
s
expe
ct
i
ng.
The
a
d
d
r
esses
al
l
o
t
t
e
d t
o
t
h
e devi
ces
by
t
h
e m
a
st
er coul
d
b
e
ran
dom
a
nd the addres
s as such
doe
s no
t dictate th
e p
r
io
rity o
f
th
e salv
es to
resp
ond
.
However th
e m
a
ster s
h
ou
ld
h
a
v
e
a
mech
an
ism
u
s
i
n
g
wh
ich
it can
prio
ritise th
e
requ
ests
to the salves a
s
per t
h
e m
e
ss
age fl
ow
requi
r
ed
by th
e di
st
ri
b
u
t
e
d em
bed
d
ed sy
st
em
.Th
e
appl
i
cat
i
on
r
u
n
n
i
n
g
on
t
h
e m
a
st
er can
be
dy
nam
i
cal
l
y
fed t
h
e
a
d
d
r
esses
and t
h
e se
quence
in which t
h
e m
e
ssages
should
flow
u
s
ing
th
e ad
dresses th
at were allo
cated
to
th
e d
e
v
i
ce b
y
usin
g
an
app
licatio
n
on
th
e PC wh
ich
is in
t
e
rfaced
with the m
a
ste
r
de
vice. T
h
e addresses t
o
the
slave de
vices
can be allocate
d
as pe
r the pri
o
rity of the m
e
ssage
flow.
A typ
i
cal
add
r
ess allo
catio
n
sch
e
m
e
th
at can
b
e
i
n
itiat
e
d
fro
m
PC is sh
own
in th
e Tab
l
e 2.
Tab
l
e 2
.
Ad
dress
allo
cation
al
g
o
rith
m
Serial
Nu
m
b
e
r
of
device
T
y
pe of
device
Device M
odel
Nu
m
b
e
r
Allocated
addr
ess
Trans
m
ission
reception
priority
Reason for
assigni
ng the pr
ior
ity
1.
M
a
ster
L
P
C2148
70
1
M
a
ster has the pr
ior
ity
over
the salves
2.
Slave-
1
89C51
60
2
T
e
m
p
-
1
flow befor
e
other
m
e
ssages
3.
Slave-
-
2
AT
89S52
50
3
T
e
m
p
-
2
m
u
st follow tem
p
-
1
in a f
r
action of
10µsec
4.
Slave-
3
PI
C18F4550
40
4
M
e
ssage to pu
m
p
-1
m
u
st follow tem
p
-
2
within
20µsec
5.
Slave-
4
ATm
e
ga328
30
5
M
e
ssage to pu
m
p
-2
m
u
st follow the
m
e
ssage to
pu
m
p
-1 within 10µsec
Evaluation Warning : The document was created with Spire.PDF for Python.
I
J
ECE
I
S
SN
:
208
8-8
7
0
8
N
e
t
w
orki
ng
He
t
e
roge
ne
ous
M
i
croco
n
t
r
ol
l
e
r
bas
ed
Syst
e
m
s
t
h
ro
u
g
h
…
(Sastry KR Ja
mma
lam
ada
ka
)
1
000
Ho
we
ver t
h
e
m
e
ssages f
r
om
t
h
e sl
aves ca
n
be o
f
di
ffe
re
nt
pat
t
e
rns
an
d t
h
e sam
e
are t
o
b
e
han
d
l
e
d as
p
e
r th
e
p
r
iorities attach
ed
to
th
o
s
e m
e
ssag
e
s. Th
e co
mm
u
n
i
catio
n
software run
n
i
n
g
o
n
t
h
e m
a
ster, will
p
o
s
t a
messag
e
alo
ng with
its p
r
iority to
a q
u
e
u
e
an
d
a qu
eu
e
h
a
nd
ler
will d
e
sp
atch
th
e m
e
ssag
e
s as
p
e
r th
e
p
r
i
o
rities attach
ed
to
t
h
e m
e
s
s
ag
es. Th
e work
i
n
g
o
f
th
e
p
r
io
rity b
a
sed
d
i
sp
atch
i
n
g
syst
e
m
fo
r effectin
g
th
e
fl
o
w
of c
o
nt
r
o
l
o
f
m
e
ssages a
s
re
qui
red
by
t
h
e
di
st
ri
b
u
t
e
d
em
bedde
d a
p
pl
i
cat
i
on i
s
s
h
o
w
n i
n
t
h
e
Fi
g
u
re
4.
Fi
gu
re
4.
Pri
o
ri
t
y
based
m
e
ssage
di
spat
c
h
i
n
g
m
e
t
hod
2.
5.
Desi
gni
n
g
Des
cri
ptors
f
o
r
C
o
nfi
g
uri
n
g
the
Sl
a
v
es
The sal
v
e ba
se
d sy
st
em
s t
h
at
are i
n
t
e
r
f
ace
d t
h
r
o
ug
h
USB
c
a
n
be co
n
f
i
g
ur
ed t
h
ro
u
g
h
di
f
f
e
rent
t
y
pe
s
of
desc
ri
pt
ors
.
Di
f
f
ere
n
t
det
a
i
l
s
of
t
h
e
sal
v
e
s
can
be
m
a
de avai
l
a
bl
e t
o
t
h
e m
a
st
er t
h
r
o
ug
h
desc
ri
pt
or
s. T
h
e
descri
pt
o
r
s
des
c
ri
bes
m
a
nufa
c
t
u
rer
I
D
,
t
h
e
versi
o
n
of t
h
e
devi
ce,
t
h
e
ve
r
s
i
o
n
o
f
USB
i
t
su
p
p
o
r
t
s
,
w
h
a
t
t
h
e
device is, its powe
r re
quirements and t
h
e num
ber of e
n
d
p
o
i
n
t
s
et
c. T
h
e m
o
st
com
m
onl
y
used
USB
descr
i
pt
or
s
i
n
cl
ude
De
vi
ce
desc
ri
pt
o
r
,
C
o
nfi
g
u
r
at
i
o
n
d
e
s
c
ri
pt
o
r
,
I
n
t
e
rfa
ce desc
ri
pt
o
r
a
n
d
E
n
d
p
o
i
n
t
de
scri
pt
o
r
Device
descri
ptor re
prese
n
t
s
the entire
device.
It provides t
h
e ge
neral inform
ation s
u
c
h
as
m
a
nufact
ure
r
I
D
, seri
al
n
u
m
b
er, p
r
o
d
u
ct
n
u
m
ber, t
h
e cl
ass of t
h
e
devi
ce
and t
h
e
num
ber of c
o
n
f
i
g
u
r
a
t
i
ons.
C
o
n
f
i
g
urat
i
o
n
descri
pt
o
r
pr
o
v
i
des t
h
e i
n
f
o
rm
at
i
on ab
out
t
h
e
po
wer re
q
u
i
r
e
m
ent
s
of t
h
e d
e
vi
ce and
ho
w
m
a
n
y
diffe
re
nt interfaces it supports. The
r
e m
a
y be m
o
re
tha
n
one c
o
nfiguration
for a
device. T
h
e int
e
rface
descri
ptor spec
ifies the class
of the
interfac
e and the number of endpoi
nt
s i
t
uses. The
r
e
m
a
y be
m
o
re t
h
an
one i
n
t
e
rface
.
T
he En
d
poi
nt
descri
pt
o
r
spec
i
f
i
e
s t
h
e t
r
ansf
er t
y
pe, di
rect
i
o
n
,
p
o
l
l
i
ng i
n
t
e
rval
, a
nd m
a
xim
u
m
packet
size for each
endpoi
nt. E
n
dpoint0
is
the de
fa
ult endpoi
nt, is al
ways assum
e
d to be a control e
n
dpoi
nt
and
ne
ve
r has a
desc
ri
pt
o
r
.
In
ad
d
ition
to ab
ov
e m
e
n
t
i
o
n
e
d
d
e
scri
p
t
o
r
s t
h
e USB p
r
o
t
o
c
o
l
suppo
rt th
e i
n
clu
s
i
o
n
o
f
m
o
re
appl
i
cat
i
o
n s
p
e
c
i
f
i
c
desc
ri
pt
o
r
s. A
ne
w
descr
i
pt
or i
s
desi
gn
ed f
o
r m
a
ki
ng
avai
l
a
bl
e t
h
e
p
r
i
o
ri
t
y
o
f
t
h
e
d
e
vi
ce
to
th
e sal
v
e so th
at th
e sam
e
can
b
e
stored with
in
it
whic
h ca
n be
use
d
by the sla
v
e to chec
k whethe
r the
r
e
qu
ir
ed
me
s
s
a
g
e
f
l
ow
is b
e
in
g a
f
f
e
c
t
e
d
an
d r
e
po
r
t
th
e
ir
r
e
g
u
l
ar
s
e
qu
en
c
e
to
th
e ma
s
t
e
r
wh
en
su
ch
ev
en
t
hap
p
e
n
s.
2.
6.
Desi
gni
n
g
D
a
t
a
P
a
cke
t
s
In USB
,
th
e d
a
ta is tran
sferred
in th
e
fo
rm
o
f
packets. Normally it cons
ist
s
of three
pac
k
ets.
1.
To
ken
packet
i
s
t
h
e hea
d
er
d
e
fi
ni
n
g
t
h
e t
r
a
n
sact
i
o
n t
y
pe and
di
rect
i
o
n,
t
h
e de
vi
ce ad
d
r
ess, a
nd t
h
e
en
dpo
in
t.
2.
Data is tran
sferred in
a Data
pack
et.
3.
The status
of t
h
e tra
n
saction i
s
sent
by
th
e ack
now
ledg
em
en
t th
ro
ugh
H
a
ndsh
a
k
e
p
ack
et.
In a tran
saction
,
d
a
ta is transferred eith
er fro
m
the USB
host to an
USB
Device
or
vice
-ve
r
sa. T
h
e
trans
f
er
direction is s
p
ecified in th
e token
packet that is sent from
the USB Host. The
n
, the source se
nds
a
Evaluation Warning : The document was created with Spire.PDF for Python.
I
S
SN
:
2
088
-87
08
I
J
ECE Vo
l. 5
,
N
o
. 5
,
O
c
tob
e
r
20
15
:
992
–
1
002
1
001
d
a
ta p
a
ck
et
o
r
in
d
i
cates it
has no
d
a
ta to
tran
sfer.
In
g
e
n
e
ral,
th
e d
e
st
in
atio
n
resp
ond
s with
a h
a
nd
shak
e
packet i
ndicati
n
g whethe
r the
trans
f
er
was
s
u
ccess
f
ul.Packets coul
d
be thought of as t
h
e
sm
a
llest ele
m
ent of
d
a
ta tran
sm
issi
o
n
. Each
p
a
ck
et tran
sm
i
t
s an
in
tegral
num
ber
of
by
t
e
s at
t
h
e cur
r
ent
t
r
a
n
sm
i
ssi
on rat
e
.
Pac
k
et
s
st
art
wi
t
h
a synch
r
oni
zat
i
o
n pat
t
e
rn
, fol
l
o
w
e
d by
t
h
e dat
a
by
t
e
s of t
h
e pa
cket
, an
d co
ncl
ude
d wi
t
h
a
n
End
-
o
f
-
Packet (EOP)
signal.
All USB packet
p
a
ttern
s are tran
sm
i
tted
least sig
n
i
fican
t b
it fi
rst. Before and
after th
e
packet, the
bus
is in i
d
le state.
The
dat
a
packe
t
desi
g
n
of
t
e
m
p
1
p
r
ocessi
n
g
sy
st
em
i
s
sho
w
n i
n
t
h
e
Tabl
e
3.
Tabl
e 3. Dat
a
packet
desi
gn
of
t
e
m
p1
pr
oce
ssi
ng
sy
st
em
Tok
e
n Pac
k
et
Sync
IN
ADDR
ENDP
CRC
0000 0
001
0110 1
001
0111
100
0 5
bits
Data Pac
k
et
Sync
Data0
Data
CRC
0000 0
001
1100 0
011
2 by
tes
16 bits
Handsha
k
e
Pac
k
e
t
Sync
ACK
0000 0
001
1101 0
010
The
dat
a
packe
t
desi
g
n
of
t
e
m
p
2
p
r
ocessi
n
g
sy
st
em
i
s
sho
w
n i
n
t
h
e
Tabl
e
4.
Tabl
e 4. Dat
a
g
r
am
desi
gn o
f
t
e
m
p2 pr
ocessi
ng
sy
st
em
Tok
e
n Pac
k
et
Sync
IN
ADDR
ENDP
CRC
0000 0
001
0110 1
001
0110
010
0 5
bits
Data Pac
k
et
Sync
Data0
Data
CRC
0000 0
001
1100 0
011
2 by
tes
16 bits
Handsha
k
e
Packet
Sync ACK
0000 0
001
1101 0
010
The
dat
a
packe
t
desi
g
n
of
p
u
m
p1 pr
ocessi
n
g
sy
st
em
i
s
sho
w
n
i
n
t
h
e Ta
bl
e 5.
Tabl
e 5. Dat
a
packet
desi
gn
of
p
u
m
p1 pr
oc
essi
ng
sy
st
em
Tok
e
n Pac
k
et
Sync
OUT
ADDR
ENDP
CRC
0000 0
001
1110 0
001
0101
000
0 5
bits
Data Pac
k
et
Sync
Data0
Data
CRC
0000 0
001
1100 0
011
2 by
tes
16 bits
Handsha
k
e
Pac
k
e
t
Sync
ACK
0000 0
001
1101 0
010
The
dat
a
packe
t
desi
g
n
of
p
u
m
p2 pr
ocessi
n
g
sy
st
em
i
s
sho
w
n
i
n
t
h
e Ta
bl
e 6.
Tabl
e 6. dat
a
p
acket
de
si
g
n
of
p
u
m
p2
p
r
oces
si
ng
sy
st
em
Tok
e
n Pac
k
et
Sync
OUT
ADDR
ENDP
CRC
0000 0
001
1110 0
001
0011
110
0 5
bits
Data Pac
k
et
Sync
Data0
Data
CRC
0000 0
001
1100 0
011
2 by
tes
16 bits
Handsha
k
e
Pac
k
e
t
Sync
ACK
00
1
1101
0
3.
RESULTS
A
N
D
DI
SC
US
S
I
ON
Ex
peri
m
e
nt
s have bee
n
c
o
n
d
u
ct
ed
usi
n
g t
h
e USB
net
w
o
r
k desi
gne
d a
n
d t
h
e
di
st
ri
b
u
t
e
d em
bedde
d
appl
i
cat
i
o
n sy
st
em
& t
h
e com
m
uni
cat
i
on sy
st
em
im
pl
ement
e
d. C
o
m
m
u
n
i
cat
i
on i
s
eff
ect
ed by
m
a
king t
h
e
Evaluation Warning : The document was created with Spire.PDF for Python.