TELKOM
NIKA Indonesia
n
Journal of
Electrical En
gineering
Vol.12, No.5, May 2014, pp
. 3805 ~ 38
1
0
DOI: http://dx.doi.org/10.11591/telkomni
ka.v12i5.5114
3805
Re
cei
v
ed
No
vem
ber 1
1
, 2013; Re
vi
sed
De
cem
ber 3
0
,
2013; Accep
t
ed Jan
uary 1
2
, 2014
Intelligent Network Temperature and Humidity
Measuring System Based on USB Interface
Huan
g Zhigu
o*
1
, Huang Zhixin
2
, Cui Xi
he
3
, Han She
ngli
4
1,3,
4
Center of Industria
l T
e
chnolo
g
y
, C
h
e
ngd
e Petrole
u
m C
o
lle
ge
High
e
r Educ
ati
on Meg
a
Ce
nter, Chen
gd
e Ci
t
y
, Heb
e
i Provi
n
ce, Chi
na, Ph
./F
ax: +
86031
4
-
237
464
7
2
Pera Corp
orat
ion Ltd.
Buil
din
g
Cn
08, No.1 Bal
i
zhu
a
n
gdo
ngl
i, Cha
o
y
ang D
i
strict, Beijin
g, Chi
na, Ph
./Fax: +
86010
5
216
76
80
*Corres
p
o
ndi
n
g
author, e-ma
i
l
: 2784
12
27@
q
q
.com
1
, cuixi
h
e
123
@16
3
.com
3
A
b
st
r
a
ct
Multi di
gital
output rel
a
tive
humidity an
d te
mp
eratur
e
sensors-SHT
71 w
e
re set netw
o
rk
m
o
nitoring points in the system
, which can m
eas
ure
at any m
o
ment, tim
i
ng, real-time tem
per
ature and
relativ
e
h
u
m
id
ity per
po
int
of the
envir
on
men
t
by-turn.
T
e
mperatur
e-hu
mid
i
ty val
ue, dew
-poi
nt
val
ue, da
t
e
and ti
me per p
o
int w
e
re displ
a
yed by lattic
e
grap
hi
cs LCM
(Liq
uid Crystal
Displ
ay Mod
u
l
e
) HY-128
64K.
At
the same time, they w
e
re saved in no
nvo
l
ati
l
e F
R
AM (F
erroel
ectric Ran
d
o
m Access Me
mory) F
M
31
25
6,
which can ass
u
re dat
a do
not lose after t
he power
of the system
fail.
Acqui
red data c
an be
uploaded
directly to PC i
n
the USB-HO
ST
mod
e
or be
copie
d
in
di
rect
ly to PC far aw
ay from testin
g
field by flas
h d
i
sk
in the
USB-DE
VICE mo
de. T
he a
ppl
icati
on
softw
are not o
n
ly ca
n draw
temper
ature, h
u
midity
and
de
w
-
poi
nt curve an
d calcul
ate
ma
ximu
m,
mi
ni
mum, aver
ag
e, but also ca
n ma
k
e
further statistical an
aly
s
is,
report forms
pri
n
ting a
nd set-u
p
basic
me
asur
e para
m
eters o
f
the system.
Ke
y
w
ords
:
te
mp
eratur
e-hu
mi
dity, USB int
e
rface, netw
o
rk, F
R
AM
Copy
right
©
2014 In
stitu
t
e o
f
Ad
van
ced
En
g
i
n
eerin
g and
Scien
ce. All
rig
h
t
s reser
ve
d
.
1. Introduc
tion
T
e
mp
er
a
t
ur
e
-
h
u
m
id
ity meas
u
r
e
m
en
t was
us
ed
e
x
ten
s
ively in in
du
strial
and
ag
ricultural
prod
uctio
n
, daily life and resea
r
ch-d
evelopme
n
t.
For example, h
eavy humidity causes to
go
mouldy and
go bad in grain, medici
n
e
s, cig
a
rette
and tea wa
reho
use. If tempe
r
ature and
humidity in
cotton wa
re
ho
use
are un
sui
t
able, sp
onta
neou
s
com
b
u
s
tion
will ta
ke
place in it. T
he
perfo
rman
ce
of the preci
s
e in
strum
e
n
t
and semi
condu
cting d
e
vice is re
du
ced b
e
cau
s
e
of
sup
e
rh
eating.
So temperat
ure
-
humi
d
ity in much
e
n
vironmental fiel
ds ne
ed
s to be measured a
nd
controlled stri
ctly.
The tradition
al Tem
p
e
r
atu
r
e-humidity
meas
urement
ado
pted th
e
metho
d
of
measuri
n
g
the temp
erat
ure
and
h
u
m
i
dity sep
a
rat
e
ly, whi
c
h
can n
o
t well
get ri
d of th
e inte
rfere
n
ce of
temperature
whe
n
mea
s
u
r
ing humidity. In addition,
the intercha
n
geability of the sen
s
o
r
is b
ad,
the circuit is compli
cated,
and it need
s long
-t
ime
and compli
ca
ted calib
ratio
n
[1, 2]. At the
pre
s
ent time,
the dome
s
tic research in t
e
mpe
r
at
ure a
nd humi
d
ity measurement
is in focal ti
me,
su
ch as
Na
njing Unive
r
sity of Aeronautics
and
Astronauti
c
s, Beijing Intelligen
ce Tu
owei
Tech
nolo
g
ica
l
Re
sea
r
ch In
stitute, Heb
e
i
Normal
University of Sci
e
nce
and T
e
chnolo
g
y, Electric
and Inform
ation Engin
eeri
ng Institute o
f
Hunan
Univ
ersity, HL
J A
ugu
st First Land Recl
ama
t
ion
University et
c. But the
abo
ve-mentio
ned
mea
s
u
r
em
e
n
t wa
s finish
ed by
di
scret
e
sen
s
o
r
, whi
c
h
wa
s low
mea
s
ureme
n
t pre
c
isi
on, sin
g
le
-point me
a
s
u
r
i
ng not to be
suitabl
e to large green
hou
se
environ
ment and
ad
opts RS232 se
rial
comm
uni
cati
on what ha
s
low dat
a tran
smissio
n
ba
u
d
s
not to meet p
r
esent tren
d in developm
e
n
t of comput
e
r
interfa
c
e. In
foreign
cou
n
try, the research
in the field
is
more
matu
re
and h
a
s hig
h
degree
of a
c
cura
cy, su
ch
a
s
Ame
r
ican
DeltaTRAK a
n
d
QUAT
RO
NIX co
mpa
n
y, G
e
rma
n
y Te
sto
Co
mpa
n
y, Au
stria,
Finla
n
d
, Ja
pan,
etc.
But they
are
so
expen
sive that the majorit
y
users in ou
r country
can
not afford the
m
.
To the
ab
ove
dom
esti
c a
n
d
inte
rnatio
na
l cu
rrent
situa
t
ion, the
syst
em a
dopt
s lat
e
-mo
del
temperature
-
humidity integration di
gital
output
sen
s
or-S
HT1
1
to comp
ose net
work mea
s
u
r
i
n
g
points, whi
c
h has high
mea
s
ureme
n
t
accura
cy,
goo
d l
ong-te
rm
sta
b
ility and fa
st re
spo
n
se tim
e
.
Data a
c
q
u
ire
d
by multi SHT11
not onl
y can b
e
upl
oade
d directl
y
to PC throu
gh USB inte
rfa
c
e
but also can
be keep in
n
onvolatile F
R
AM-FM3
1256
, which can n
o
t lose
even
if the system
is
Evaluation Warning : The document was created with Spire.PDF for Python.
ISSN: 23
02-4
046
TELKOM
NI
KA
Vol. 12, No. 5, May 2014: 3805 – 38
10
3806
power-fail. M
o
re i
m
po
rtan
t, commu
nication b
e
twe
e
n
the
micro
c
omp
u
ter an
d the P
C
h
a
s
repla
c
e
d
trad
itional
RS23
2 serial
inte
rface
by do
u
b
le-m
ode
US
B interfa
c
e
(USB-HOST
and
USB-DEVICE
), which ca
n be implem
ent
ed not only dire
ctly but also indire
ct
ly throug
h flash di
sk.
So the syste
m
has
small i
n
terface, plug
and play and
better universal pe
rform
a
n
c
e.
2. The Gross
Structu
r
e of the Sy
stem
The
system i
s
ma
de
up of
the PC
and
the mi
cro
c
o
m
puter. T
he mi
cro
c
o
m
pute
r
rega
rd
s
AT89C52 as t
he co
re, whi
c
h is made up
of data acqui
sition network, LCD mod
u
le
, data memory
module
and
USB com
m
u
n
icatio
n mod
u
le to finish
acq
u
isitio
n, d
i
splay, mem
o
ry and u
p
loa
d
ing
temperature
and h
u
midity
data. It not o
n
ly can
a
c
qui
re
d
a
ta o
r
sto
p
at any time
by the
key,
but
also
can
do t
h
rou
gh
whi
c
h
the co
rre
sp
o
nding a
ppl
i
c
a
t
ion software
of the system
set acqui
sition
initial time, st
op time
and
time interval.
In ad
dition,
it has a
c
ou
st
o-opti
c
al
arm
functio
n
wh
en
temperature
and humi
d
ity of the enviro
n
ment is ov
e
r
pre
-
setting range. The P
C
is mad
e
u
p
o
f
data processing an
d pa
ra
meter
setting
, which c
an
dra
w
curve,
list displayin
g
, mathemati
c
analysi
s
, statistical an
alysi
s
rep
o
rt printi
ng and
set up paramete
r
s of the micro
c
ompute
r
su
ch
as
start
and
stop
time, time int
e
rval, up
pe
r a
nd lo
we
r
limit value
to alarm
etc.
T
he gross stru
cture of
the system i
s
as sho
w
n in
Figure 1.
2.1. Data
Ac
quisition Ne
tw
o
r
k
The sy
stem u
s
e
s
multi temperatu
r
e
-
hu
m
i
dity
integration digital out
put sen
s
o
r-S
HT11 to
do multiple
-p
oint mea
s
u
r
e
m
ent by-tu
r
n,
whi
c
h i
n
tegrate tempe
r
at
ure
and
hum
idity respon
se
element, sig
nal amplifie
r, A/D convert
e
r,
OTP RO
M (One Ti
m
e
Prog
ramm
able Read
Only
Memory
), I2C bus et
c. peri
pheral ci
rcuit. It outputs
directly digital si
gnal of the re
lative humidity
and te
mpe
r
at
ure
after calibration.
It strengthe
ns si
g
nal inte
nsity
and
anti-inte
rferen
ce
and
l
ong-
time stability,
whi
c
h re
solve
s
availably de
ficien
cy of traditional temp
eratu
r
e an
d humidity sen
s
o
r
.
In additio
n
, it
can
al
so
mea
s
ure
de
w-p
o
i
n
t accu
ra
tely,
whi
c
h
will n
o
t
introd
uce e
r
ror be
ca
use
of
the temperature differen
c
e
of temperatu
r
e and h
u
midi
ty [3, 4].
From Figu
re
2 (relative humidity digital
output pe
rforma
nce cu
rve), we can
see it
appe
ars n
o
n
-
linea
rity. Th
e sy
stem
ad
opted m
e
tho
d
of
softwa
r
e to
com
p
e
n
sate
it to
gain
accurate data
.
The formula
to amend hu
midity value is as follo
ws:
In the above formul
a,
RH
SO
is rel
a
tive humidity measu
r
in
g value of the se
nso
r
, whi
c
h is
as follows (th
e
humidity ca
n sele
ct from
14 or
12 bit, the temperat
ure can sel
e
ct from 12 or
8
bit):
12 bit
RH
SO
：
1
C
= -4
2
C
= 0.0405
3
C
= -2.
8
×1
0-6
8 bit
RH
SO
：
1
C
= -
4
2
C
= 0.6480
3
C
= -7.
2
×10
-
4
Figure 1. The
Gro
ss Stru
ct
ure
Blo
ck
Dia
g
ram of the S
y
stem
AT89C52
USB
FRAM
LCD
PC
Parameters
i
R
e
po
r
t
p
r
in
ting
Data an
alysi
s
C
u
r
v
e
dr
aw
ing
…
Se
n
s
or
n
Se
n
s
or
3
Se
n
s
or
2
Se
n
s
or
1
…
RH
RH
RH
linear
SO
SO
C
SO
C
C
RH
3
2
1
Evaluation Warning : The document was created with Spire.PDF for Python.
TELKOM
NIKA
ISSN:
2302-4
046
Intelligent Net
w
ork Tem
p
e
r
ature an
d Hu
m
i
dity Measu
r
ing System
Based o
n
… (Hua
ng Zhig
u
o
)
3807
The
above
fo
rmula
is u
s
e
d
to
cal
c
ulate
humidity valu
e in
the
ca
se
of
25
Ԩ
, but
the real
measuri
ng te
mperature i
s
cha
nge
d with
in the spe
c
ific ran
ge, so t
e
mpe
r
at
ure coefficient of the
humidity sen
s
or
sho
u
ld b
e
con
s
ide
r
e
d
, which
can b
e
comp
en
sat
ed acco
rdin
g
to the following
formula:
In the above formul
a,
T
is an
actual temp
erature value.
Its
c
o
effic
i
ent is
as
follows
:
12 bit
RH
SO
：
1
t
= 0.
0
1
2
t
= 0.000
08
8 bit
RH
SO
：
1
t
= 0.01
2
t
= 0.0012
8
The tempe
r
at
ure line
a
rity of the SHT71 is very good, so tempe
r
atu
r
e digital outp
u
t can
be co
nversed
actual value
by the followi
ng formul
a:
In the ab
ove
formula, S
O
T is tem
p
e
r
a
t
ure o
u
tput v
a
lue of th
e
sen
s
o
r
. The
sup
p
ly
voltage of the system is 5V
.
Whe
n
the re
solution of the temperature
sen
s
o
r
is 14
bit,
01
.
0
,
40
2
1
d
d
.
Whe
n
the re
solution of the temperature
sen
s
o
r
is 12
bit,
04
.
0
,
40
2
1
d
d
.
The
de
w-p
o
in
t value of
the
environ
ment
can
be
calcul
ated a
c
co
rdin
g to
relative
h
u
midity
and tempe
r
at
ure by the followin
g
formul
a:
2.2. LCM (Li
quid Cr
y
s
tal Displa
y
Mod
u
le)
LCM a
dopts l
o
w con
s
ume
d
power
HY-1286
4K mod
u
le, whi
c
h ca
n displ
a
y temperatu
r
e,
humidity, de
w point, no
w
time and dat
e of every m
onitorin
g
poi
n
t
together, so
that it can m
a
ke
use
r
s m
onitor more conven
iently the environm
en
t. The
LCM ado
pts
LED blue b
a
ck lighting
wha
t
is
controlled
by key, which can m
a
ke
use
r
s
read te
mperature
an
d humi
d
ity value u
nde
r di
m-
beam o
c
casi
on.
0 500 1000 1500 2000 2500 3000
100%
80%
60%
40%
20%
0%
Relati
ve humi
d
ity
Digital outp
u
t
Figure 2. The
Relative Hu
midity Digital
Output Perfo
r
mance Cu
rve
of the SHT71
linear
RH
true
RH
SO
t
t
T
RH
)
(
)
25
(
2
1
T
SO
d
d
TC
2
1
2
10
log
3
.
237
/
5
.
7
66077
.
0
RH
T
T
LogEW
16077
.
8
/
3
.
237
66077
.
0
LogEW
LogEW
D
P
Evaluation Warning : The document was created with Spire.PDF for Python.
ISSN: 23
02-4
046
TELKOM
NI
KA
Vol. 12, No. 5, May 2014: 3805 – 38
10
3808
2.3. Data M
e
mor
y
Module
Und
e
r a
lot of occa
sion
s (su
c
h
as
high
ri
sk o
c
ca
sion,
seal
ed environm
ent etc.),
comm
uni
cati
on b
e
twe
en t
he PC an
d th
e micro
c
om
p
u
ter
can
not
be exe
c
ute
d
dire
ctly and
real-
time, so hist
orical tempe
r
ature an
d hu
midi
ty data need re
co
rdin
g, and then they will be d
one
cure-dra
win
g
, analysi
s
pro
c
e
ssi
ng, repo
rt-p
rint
ing, et
c. The
system
adopt
s adva
n
c
ed
nonvol
atile
FRAM-FM31
256, which
has
10 yea
r
s rete
ntion
t
i
me after p
o
w
er-fail, unli
m
ited re
ad/write
endu
ran
c
e. So it assu
re
s histori
c
al d
a
ta memory
rel
i
ability. In ad
dition, the memory integ
r
ate
s
RTC (real
-time cl
ock), low-V
D
D reset circuit
(in
s
tead
of sep
a
rate
clo
c
k
chip
-DS
1302
) an
d
watchdo
g
tim
e
r circuit (in
s
tead of
X504
5
chi
p
),
whi
c
h
make
s th
e
system h
a
s hig
her i
n
tegratio
n
and better
reli
ability [5, 6].
2.4. USB Co
mmunicatio
n Module
USB interfa
c
e ha
s g
o
t ex
tensive
popul
arizat
ion and
appli
c
ation
with
a
great deal of
cha
r
a
c
teri
stics such a
s
its plu
g
and
play, c
onve
n
ience, apt ex
pandi
ng, hig
h
sp
eed. But
,
to
develop
ers, rese
archin
g USB inte
rface
is not a easy
thing, becau
se it requi
re
s develope
rs t
o
comp
re
hen
d deeply USB stand
ard, firmwa
re progr
amme and d
r
iver com
p
ilin
g, which re
strain
s
gene
ral
hard
w
are e
ngine
er'
s
devel
op
ment to US
B
interfa
c
e p
r
odu
cts [4]. B
u
t, in the sy
stem,
universal
US
B interfa
c
e
chip
CH375
is
use
d
. It only
need
s
develo
pers to
p
r
og
ram
sigle
c
hip
and
PC ap
plicatio
n software, so it ha
s ma
n
y
cha
r
a
c
teri
stics
su
ch
a
s
a
p
t usin
g, sho
r
t develo
p
me
nt
perio
ds. Mo
re
important, it sup
port
s
US
B-HOST m
o
d
e
and USB-DEVICE mode.
The system has bro
k
e
n
t
h
rou
gh
traditi
onal singl
e USB
extern
a
l
device and
adopt
s
doubl
e USB plug seat mo
de, whi
c
h en
able it not
onl
y can wo
rk in
USB-DEVICE mode but a
l
so
be u
s
ed i
n
USB-HOST m
o
de, so it
provi
des
more
con
v
enien
ce to d
i
fferent u
s
ers
and o
c
ca
sion
s.
The interfa
c
e
circuit of the CH375 a
nd SCM is a
s
sho
w
n in Figu
re
3 [7-10].
SCM ju
dge
s
whi
c
h
USB pl
ug
seat i
s
wo
rkin
g by
high
or lo
w level o
f
the STAT
US sig
nal,
and the
n
ma
kes
su
re
whi
c
h co
mmuni
ca
tion mod
e
the
system i
s
wo
rkin
g in. If the
port P5
2 join
ts
PC, the CH3
75 wo
rks i
n
d
e
vice mo
de. If the port P5
1
joints USB d
e
vice (su
c
h
a
s
flash disk), the
CH375
wo
rks in h
o
st m
o
de. The
both
can
'
t wo
rk
a
t
the sam
e
time. Un
der th
e idle
situati
on,
STATUS si
g
nal is l
o
w l
e
vel, SCM m
a
ke
s
the CH375 works
in
the
ho
st m
ode. When
USB
appa
ratu
s in
sert
s P5
1, th
e CH37
5
will
inform
aut
o
m
atically SCM to de
al wi
th co
rrespon
ding
work.
Whe
n
the P52 j
o
ints with
USB po
rt of the PC,
5V voltage of
the PC m
a
kes the
STAT
US
become lo
w level, and the
n
SCM monit
o
rs th
e STATUS sign
al to swit
ch the CH37
5 to device
mode [11, 12]
.
The dou
ble mode USB interface ma
kes the sy
ste
m
more univ
e
rsal, more
convenie
n
t
and meetin
g much o
c
ca
sio
n
.
Y5
12
M
H
z
C5
2
15
P
C5
1
15
P
C5
5
0.
4
7
u
F
C5
4
0.
1u
F
C5
3
10
0
u
F
VC
C
VC
C
1
1
2
2
3
3
4
4
P5
1
HO
S
T
1
1
2
2
3
3
4
4
P5
2
DEV
I
C
E
D-
D+
R5
1
1K
R5
2
1K
ST
A
T
U
S
R5
3
3.
3K
C5
6
10
0uF
L5
V
CC
1:
D
E
V
I
C
E
0:
H
O
S
T
D0
D1
D2
D3
D4
D5
D6
D7
A8
A1
5
RD
WR
IN
T
0
R5
4
1K
D5
VC
C
RS
T
D0
15
D1
16
D2
17
D3
18
D4
19
D5
20
D6
21
D7
22
A0
8
RD
#
4
WR
#
3
CS
#
27
IN
T
#
1
RS
T
25
RST
#
26
VC
C
28
V3
9
TXD
5
GN
D
12
GN
D
23
UD
-
11
UD
+
10
RST
I
2
XI
13
XO
14
AC
T#
24
RX
D
6
U5
CH
3
7
5
S
Figure 3
．
Th
e Interface Ci
rcuit Di
ag
ram
betwee
n
CH375 an
d SCM
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TELKOM
NIKA
ISSN:
2302-4
046
Intelligent Net
w
ork Tem
p
e
r
ature an
d Hu
m
i
dity Measu
r
ing System
Based o
n
… (Hua
ng Zhig
u
o
)
3809
2.5. The App
lication Softw
a
r
e
an
d Dri
v
er
in the PC
The PC appli
c
ation softwa
r
e and d
r
iver adopt visual
programmin
g
langua
ge - Visual
Basic to p
r
o
g
ram. T
he d
r
iver fini
she
s
USB comm
unication Pro
t
ocol inte
rfa
c
e program
with
system software.
The appl
ication softwa
r
e
is
m
ade u
p
of data pro
c
essing a
nd p
a
ram
e
ter
setting
module,
whi
c
h can
reali
z
e
the follo
wing
functio
n
s: te
mperature,
h
u
midity and
dew-poi
nt curve
dra
w
ing,
sho
w
ing m
a
ximu
m, minimum
and me
an i
n
any time i
n
terval, to transfe
r Mi
cro
s
oft
Office Excel
to display
data in list, statistica
l an
alysis a
nd report p
r
inting
. In addition, the
softwa
r
e
ca
n
set m
any p
a
ram
e
ters of
the
system
(su
c
h
a
s
start and
stop
time, time inte
rval,
startup
mod
e
,
memory mo
de, wa
rnin
g thre
shol
d
of t
e
mpe
r
ature a
nd humi
d
ity value et
c.). Th
e
gro
ss
stru
ctu
r
e of the software in
te
rface is as
sho
w
n Fi
gure 4.
3. The Exper
i
mental Res
u
lt and Its Analy
s
is
Thro
ugh te
sted in green
h
ouse, the system is co
nfirmed that it has very hig
h
accuracy
and mea
s
u
r
in
g effect. Temperatu
r
e an
d humidity curv
es in the Fig
u
re 5 were d
r
awn a
c
cordin
g
to actual a
c
q
u
iring d
a
ta in
the green
ho
use. Mea
s
u
r
i
ng time interval of these data is 5 second.
Tempe
r
atu
r
e
error d
oes
n
o
t exceed
± 0.4 and hu
mi
dity erro
r doe
s not exce
ed
±3.0% throu
gh
comp
ari
ng
a
nd a
nalyzi
n
g
with
the
sta
ndard tem
p
e
r
ature
sy
stem
and
hyg
r
om
eter.
Nonvol
a
t
ile
memory
ca
n
store mo
re
than 1
600
0
gro
up
dat
a.
Wh
en the
system i
s
u
s
ed
und
er the
environ
ment whi
c
h
tem
perature and hu
midity
cha
n
g
e
slo
w
ly, it ca
n mea
s
u
r
e fo
r ab
out 22
0 d
a
ys
contin
uou
sly by gatherin
g once at in
tervals of every 2
0
minutes.
4. Conclusio
n
The sy
stem
use
s
adva
n
ced sin
g
le bu
s sen
s
o
r
,
whi
c
h is reli
able,
stable, fully calibrate
d
and fully interch
ang
eabl
e. It not only can acquire
a
nd memo
ry tempe
r
ature a
nd humidity data
automatically long-time
bu
t also c
an do
write-protect
to these dat
a
that is a
c
q
u
ired. In ad
di
tion,
Figure 4. The
Interface Structure and F
unctio
n
Block Diagram of P
C
A
p
p
l
i
c
a
t
i
o
n
S
o
f
t
w
a
r
e
D
a
ta pro
cessing
D
r
aw
ing
cu
rv
e
Statistical analysis
I
nqu
ir
y pro
cessin
g
C
r
eat
i
ng re
po
rt
s
Prin
ting
report
Main
in
terface
C
o
m
m
uni
cat
i
o
n c
h
eck
Param
e
ters settin
g
War
n
i
n
g t
h
res
hol
d
N
ow time and
d
a
te
Time in
terv
al
Stat and stop ti
me
Mem
o
r
y
mo
de
Figure 5. The
Interface of
Cu
rve
Drawi
n
g and Data Analysi
s
Evaluation Warning : The document was created with Spire.PDF for Python.
ISSN: 23
02-4
046
TELKOM
NI
KA
Vol. 12, No. 5, May 2014: 3805 – 38
10
3810
these d
a
ta can not lo
se a
fter power-fail
beca
u
se
of the nonvol
atile FRAM. Mo
re importa
nt, the
s
y
s
t
e
m
n
o
t
on
ly c
a
n
ac
quir
e
da
ta
au
toma
tic
a
lly
according to
s
t
art time
, s
t
op
time and time
interval set b
y
users, which need not m
onitorin
g
artificially and is
suitabl
e for many dang
erous
occa
sion, bu
t also ca
n cast off the PC to r
eali
z
e
start and
sto
p
as a po
rta
b
le mea
s
u
r
in
g
instru
ment at any time,
whi
c
h ca
n make
u
s
e
r
s
more conven
ient. The double mod
e
USB
interface m
a
kes
data tran
smissi
on
more
co
nvenient
a
nd fa
st. It can
co
py data
to
lab PC by fla
s
h
disk un
der th
e locale
with
out PC. Th
e
system
ha
s
many charact
e
risti
c
s such
as hi
gh p
r
e
c
i
s
ion,
good
stability, high dep
end
ability and uni
versality etc.
Referen
ces
[1]
Xu P
i
n
g
, T
i
an Yu, et al. Researc
h
of
un
iversal tem
per
ature a
nd h
u
m
idit
y meas
ur
ement.
Chi
n
a
Instrume
ntatio
n
. 2004; (1): 35
-37.
[2]
Z
hang Z
hon
g
p
in
g. T
he research
of h
u
midit
y
me
asuri
n
g instrum
ent
base
d
o
n
ME
MS. Senso
r
T
e
chnolog
y. 2
003; (2): 11
3-1
16.
[3]
Meng
Ch
en,
Li
Min, et
al.
Dig
i
t
al T
e
mperatur
e
a
nd
Humi
dit
y
Sens
or SHT
11 Bas
ed
on
I2
C Bus
an
d Its
Appl
icatio
n i
n
t
he S
i
ng
le-ch
i
p
Microcomp
u
ter
S
y
stem.
In
te
rna
t
i
o
na
l
El
e
c
tron
i
c
Elem
en
ts
. 200
4; (2): 5
0
-
52.
[4
]
H
e
Li
mi
n
.
T
h
e d
e
s
ig
n o
f
app
l
i
c
a
t
io
n sy
stem o
f
MCS-5
1
series
SCM.
Beiji
ng: B
e
iH
a
ng U
n
iv
ersit
y
Press. 2005.
[5]
Du Z
h
o
ngl
ian
g
,
Z
hang
Xuhu
i. Appl
icatio
n of
F
M
3125
6 in M
u
lti-us
er Multi-r
a
te W
a
tt-hour
Meter.
Power
Syste
m
Eng
i
nee
ri
ng
. 200
5; 21
(4).
[6]
Z
hao
Xia
o
sh
u
n
, Yu Hual
i, et al. Desig
n
of
doub
le-mo
d
e
USB interfa
c
e of tempera
t
ure humi
d
it
y
measuri
ng a
p
p
a
ratus.
Journ
a
l
of Agricultura
l
Mecha
n
i
z
a
t
i
on
Rese
arch
. 20
0
7
; (10): 171-1
7
3
.
[7]
Che
n
Limi
ng,
T
i
an Xue
l
o
ng,
et al. USB in
terf
ace sol
u
tio
n
for the athl
e
t
e'
s heart sou
nd telem
e
tr
y
sy
s
t
e
m
.
Chi
n
e
s
e Medic
a
l Eq
uip
m
ent Journ
a
l
. 200
4; (2): 14-15.
[8]
F
eng Yu
an, Z
h
enli
a
n
g
Di
ng, h
ong C
h
e
n
. Res
earch
o
n
the i
n
flue
nce of e
n
v
ironme
n
t temperatur
e an
d
its compens
ati
on in
precis
io
n tem
per
ature me
asurem
ent
w
i
th
plat
in
um resist
ance. 20
03; 82
~
8
6
．
[9]
Nanj
in
g Qin
H
eng E
l
ectro
n
i
cs Co.Ltd.
USB bus
int
e
rface ch
ip
CH37
5
C
h
i
n
e
s
e man
ual.
http://
w
c
h.cn/d
o
w
nl
oa
d/Defa
u
l
t.asp?cl
a
ssid=
6. 2005.
[10]
LLi
Xin
l
o
ng, Z
hai Ho
ngfa
n
, et al. USB chip
CH37
5
’s a
p
p
licati
on i
n
a po
w
e
r measur
ement s
y
st
em
Contro
l & Automation. 20
06;
22(9): 31
0-3
1
2
.
[11]
Xu
Ju
n, Li
Xi
n
,
Ai H
ong,
et
al. A
Nove
l W
i
reless T
e
mper
ature M
e
ter B
a
sed
on
Quart
z
T
uning-fork
T
e
mperatureS
ensor
．
ISTM.
200
5; 374
9~
37
52
．
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