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TNG QUAN V CNG NGH ZIGBEE
1 | P a g e
MC LC
CHNG I: TNG QUAN V CNG NGH ZIGBEE .............................................................. 3
I. Tng quan v mng Zigbee: ................................................................................................. 3
1. Lch s pht trin. ............................................................................................................ 3
2. Mng Zigbee ..................................................................................................................... 4
II. Chun Zigbee/IEEE 802.15.4 ........................................................................................... 5
1. Tng vt l : ...................................................................................................................... 5
2. Tng iu khin d liu MAC .........................................................................................10
3. Tng mng ca ZigBee/IEEE802.15.4: ...........................................................................19
4. Tng ng dng ca ZigBee/IEEE 802.15.4: ....................................................................21
III. ng dng: ........................................................................................................................21
CHNG II: TM HIU PHN CNG B KIT PHT TRIN CA ZIGBEE .......................23
I. S dng phn cng. .............................................................................................................23
1. S dng SmartRF Studio vi SmartRF05EB v CC2520EM. .......................................25
2. Chy V d phn mm ng dng. ...................................................................................27
II. th nghim RF .................................................................................................................28
1. Kim tra in u ra. ........................................................................................................29
2. T l li gi (PER) th nghim. ........................................................................................29
III. RF05EB thng minh. .......................................................................................................30
1. USB MCU. ........................................................................................................................31
2. La chn ch chuyn i. ............................................................................................33
3. Nng lng pin. ................................................................................................................34
4. DC Jack. ...........................................................................................................................34
5. in USB. .........................................................................................................................34
6. Cung cp in trong phng th nghim.............................................................................34
7. RS232 giao din UART. ....................................................................................................34
8. Phm iu khin. ...............................................................................................................35
9. Mn hnh LCD. ................................................................................................................36
10. Nt. ...............................................................................................................................36
11. n LED. ......................................................................................................................36
Cc LOW BATT LED c bt khi in p t pin gim xung di khong 1.56V. ..........36
Ni tip Flash. ..........................................................................................................................36
12. G li kt ni (P18 v P20). ..........................................................................................36
13. Kt ni EM. ...................................................................................................................37
14. Ph v ra tiu v nhy (P1 v P4). ...........................................................................37
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IV. CCMSP-EM430F2618. ....................................................................................................40
1. JTAG giao din v ngun in. ........................................................................................40
2. BSL hoc kt ni UART. ..................................................................................................41
3. ch SPI. ........................................................................................................................41
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M U
Tm tt s lc: Zigbee l mt giao thc c xy dng theo chun IEEE 802.15.4. Giao thc ny
c to ra nhm phc v cho nhng ng dng yu cu gi thnh v cng sut thp nhng phi c kh nng linh ng trong phm vi rng. Chun Zigbee c pht trin v xc tin bi hng Zigbee Alliance, vi s h tr t hn 200 cng ty trn th gii nh: SIEMENS, ATMEL, NI, NEC,TEXAS INSTRUMENTS, EPSON... v bn cht Zigbee cng l mt chun giao tip khng dy nh nhng chun giao tip khng dy khc: UWB, Wi-Fi, IrDA, 3G, Bluetooth...nhng n mang nhng c tnh k thut v nhng c tnh vt l ring v do ch ph hp vi mt mng ng dng nht nh.
L do tm hiu ti: Ngy nay c rt nhiu chun khng dy (wireless) truyn d liu vi tc cao
gia cc thit b vi nhau nh BlueTooth hay Wifi. Vi nhng u im vt tri ca mnh, truyn thng khng dy ang c la chn nh l mt phng php ti u trong cc vn v truyn ti d liu. Nhng i vi nhng mng qun l cc sensor trong cc ng dng iu khin - t ng ha ca cc thit b trong ta nh hay bnh vin th Wifi hay BlueTooth li khng th p ng c. Chng c nhiu khuyt im nh s dng bng thng rng lm tiu hao nhiu in nng khng cn thit, s dng cc ngun in trc tip, t s dng pin, phm vi kt ni nh hp, tr cao, c ch bo mt n gin (BlueTooth), yu cu v cc thit b phn cng cao, chi ph ln. V gii quyt nhng khuyt im , Zigbee ra i. i tng m Zigbee nhm vo l mng iu khin dnh cho nh thng minh (SmartHome), t ng ha qu trnh (Home Automation, Building Automation), trong cc hot ng theo di, tip nhn v x l thng tin trong lnh vc y t (Health Care), qun l nng lng sao cho hiu qu hn (Smart Energy) V khi c s dng trong cc h thng ny, Zigbee c pht huy tt c nhng im mnh ca n nh tr truyn tin thp, tiu hao t nng lng, gi thnh thp, t li, d m rng v thi gian s dng pin di.
CHNG I: TNG QUAN V CNG NGH ZIGBEE
I. Tng quan v mng Zigbee:
1. Lch s pht trin.
Mng c nhn khng dy c s dng vi mc ch truyn thng tin trong nhng
phm vi tng i ngn vi cc giao thc c bit ti nh WLAN, WPAN Khng
ging nh WLAN (mng cc b khng dy), WPAN c th hot ng hiu qu m
khng i hi nhiu v c s h tng. N cho php gii quyt nhng bi ton v tit
kim chi ph, nh gn m vn em li hiu sut s dng cao trong lin lc vi bng tn
eo hp.
Nhm chun IEEE 802.15 ra i phc v cho chun WPAN. IEEE 802.15 c
th phn ra lm 3 loi mng WPAN vi tc truyn, mc tiu hao nng lng v
cht lng dch v (QoS) khc nhau, c th:
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IEEE 802.15.3 l chun WPAN tc cao ph hp vi cc dch v a phng
tin yu cu cht lng dch v cao
IEEE 802.15.1 (Bluetooth) l chun c tc trung bnh c ng dng trong
cc mng in thoi t bo n my tnh c nhn b ti (PDA) v c QoS ph
hp cho thng tin thoi
IEEE 802.15.4 / LR-WPAN (Zigbee) l chun c tc thp dung trong cc
sn phm cng nghip, cc ng dng y hc ch i hi mc tiu hao nng
lng thp, khng yu cu cao v tc truyn tin v QoS. Chnh yu t
truyn d liu vi tc thp cho php LR-WPAN tiu hao t nng lng.
2. Mng Zigbee
Nguyn l v tn gi ca mng Zigbee bt ngun t vic ghp hai ch ci u
trong kiu lin lc Zig-Zag ca loi ong honeyBee. c im ca cng ngh Zigbee l
tc truyn tin thp, tiu hao t nng lng, chi ph thp, l giao thc mng khng
dy hng ti cc ng dng iu khin t xa v t ng ha. Mc tiu ca Zigbee l
hng ti vic truyn tin vi mc tiu hao nng lng nh v cng sut thp cho
nhng thit b ch c thi gian sng t vi thng n vi nm m khng yu cu cao v
tc truyn tin. Hin nay IEEE 802.15.4 tp trung vo cc chi tit k thut ca tng
vt l PHY v tng iu khin truy nhp MAC. Cc phng php nh tuyn c
thit k sao cho nng lng c bo ton v tr trong truyn tin mc thp nht
c th.
Tc truyn d liu ca mng Zigbee l 250kbps di tn 2.4GHz, 40kbps di
tn 915MHz v 20kbps di tn 868MHz. Phm vi hot ng ca Zigbee l 10-75m,
zigbee s dng cu hnh ch t c bn ph hp vi mng hnh sao tnh trong cc
thit b giao tip vi nhau thng qua cc gi tin nh (ti a 254 nt mng). Nt mng
s dng zigbee vn hnh tn t nng lng, n c th gi v nhn gi tin trong khong
15ms.
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Hnh 1 : Cu trc lin kt mng
Hnh 2 : M hnh giao thc ca Zigbee
Mt h thng Zigbee/ IEEE 802.15.4 gm nhiu thnh phn to nn. Phn c bn
nht to nn mt mng l thit b FFD, thit b ny m nhn tt c cc chc nng
trong mng v hot ng nh mt b iu phi mng PAN, ngoi ra cn c mt s
thit b m nhn mt s chc nng hn ch l RFD
Hin nay Zigbee v t chc chun IEEE a ra mt s cu trc lin kt mng cho
cng ngh Zigbee. Cc nt mng trong mt mng Zigbee c th lin kt vi nhau theo
cu trc mng hnh sao (star), cu trc mng hnh li (Mesh) v cu trc b cm hnh
cy.
II. Chun Zigbee/IEEE 802.15.4
M hnh giao thc
Cng ngh Zigbee xy dng v pht trin cc tng ng dng v tng mng trn nn
tng l hai tng PHY v MAC theo chun IEEE 802.15.4 c trnh by trong hnh 2
1. Tng vt l :
Tng vt l cung cp 2 dch v l dch v d liu PHY v dch v qun l PHY. Dch
v d liu PHY qun l iu khin vic thu v pht ca khi d liu thng qua knh
sng v tuyn vt l
Cc tnh nng ca tng vt l l lm tng hoc gim s kch hot ca b phn nhn
sng, pht hin nng lng, chn knh, ch s ng truyn, gii phng knh truyn,
thu v pht cc gi d liu qua mi trng truyn.
.
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Hnh 3: Bng tn v tc d liu.
Hnh 4 : Bng tn h thng ca Zigbee
Hnh 4. M t 3 di tn s khc nhau theo khuyn ngh ca Chu u, Nht Bn v M.
1.1. M hnh iu ch tn hiu ca tng vt l:
+ iu ch tn hiu ti di tn 2.4GHz
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Hnh 5 : S iu ch tng PHY ti di tn 2.4GHz.
Vic iu ch t bit d liu nh phn sang dng tn hiu trong di tn 2.4GHz c
m t trong hnh 5. Mt chui s nh phn 0000b c bin i sang chui di tn
c s vi nh dng xung. S iu ch bao gm 3 b chuyn i : b chuyn i bit
thnh k t, b chuyn i k t thnh chip, v b iu ch O-QPSK
B chuyn i bit thnh k t l bc u tin m ha tt c cc d liu c
trong PPDU t m nh phn sang dng k t. Mi byte c chia thnh cc k t v
k t no c ngha nh nht c pht u tin.
B chuyn i k t thnh chip l bc th hai trong qu trnh m ha. Mi k t
d liu c sp xp trong mt chui gi ngu nhin 32-chip. Chui bit ny c
truyn i vi tc 2Mchip/s, vi chip c ngha nh nht c truyn trc mi k t.
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Hnh 6: S bin i symbol to chip
Phng php iu ch c dng y l phng php iu ch kha dch pha
gc c chn gc dch pha ban u O-QPSK tng ng vi phng php iu ch
kha dch pha ti thiu MSK. QPSK l phng php hiu qu vi di tn hn ch,
trong mi phn t tn hiu biu din cho 2 bit. Bng vic s dng dch offset
trong O-QPSK, thay i pha trong tn hiu tng hp ti a l 900, cng trong trng
hp ny m dng QPSK th lch pha ti a l 1800.
Hnh 7: Pha ca sng mang.
Biu thc sau ch ra cch m O-QPSK c th din t:
1 1( ) ( )cos 2 ( )sin 2
2 2c c cs t I t f t Q t T f t
fc : l tn s trung tm
Tc l thi gian m Q tr t ti thay i pha 900
Q: Sng mang vung pha
I : sng mang cng pha
+ iu ch tn hiu ti di tn 868/915 MHz
Hnh 8 : S iu ch tng PHY ti di tn 868/915MHz.
Tc truyn ti ca Zigbee ti bng tn 868MHz c th t ti 20kb/s, v c th
t ti 40kb/s bng tn 915MHz. S iu ch bao gm 3 b : b m ha nh phn,
b nh x bit thnh chip v b iu ch kha dch pha nh phn BPSK.
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B m ha vi phn hay cn gi l m ha trc. Khi cho tn hiu nh phn vo b
m ha ny th bit c gi tr 0 s c chuyn tip, c ngha l s c tch l s 1 nu
s lin trc n l s 0 v ngc li.
Nu mt s c tch xung sai, li ny s c xu hng lan truyn i, v loi tr
vic ny th Lender ngh vic m ha trc s cc d liu. C ngha l nu chui
s d liu th l Rn th ta s pht i chui s En theo quy tc 1n n nE R E .
Trong :
1 1 0 0 0
0 1 1 0 1
En l chui bit sau khi m ha
Rn l chui bit th
En-1 l chui bit m ha lin trc
B nh x bit thnh chip dng nh x mi bit u vo sang chui gi ngu nhin
(PN). Trong khong thi gian mi symbol th k t c0 c truyn u tin, k t c14
c truyn cui cng.
Hnh 9: B bin i bit to chip.
Chui chip c iu ch trn sng mang s dng phng php iu ch BPSK c
dng xung l xung cosin nng (raised cosine). Tc chip l 300kchip/s trong di tn
868MHz v t c 600 kchip/s trong di tn 915MHz. Dng xung ny c m t
theo cng thc
2 2
sin( ).cos( )
( )/ .(1 (4 / ))
c c
c c
t t
T Tp t
t T t T
1.2. Cc thng s k thut trng tng vt l ca IEEE 802.15.4 :
1.2.1. Ch s ED (energy detection):
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Ch s ED o c c bi b thu ED. Ch s ny s c tng mng s dng nh l mt bc trong thut ton chn knh. ED l kt qu ca s c lng cng sut nng lng ca tn hiu nhn c trong bng thng ca knh trong IEEE 802.15.4. N khng c vai tr trong vic gii m hay nhn dng tn hiu truyn trong knh ny. Thi gian pht hin v x l ED tng ng khong thi gian 8 symbol. Kt qu pht hin nng lng s c thng bo bng 8 bit s nguyn trong khong t 0x00 ti 0xff. Gi tr nh nht ca ED (=0) khi m cng sut nhn c t hn mc +10dB so vi l thuyt. ln ca khong cng sut nhn c hin th ch s ED ti thiu l 40dB v sai s l 6dB .
1.2.2. Ch s cht lng ng truyn (LQI) :
Ch s cht lng ng truyn LQI l c trng cht lng gi tin nhn c. S o ny c th b sung vo ED thu c, nh gi t s tn trn tp SNR, hoc mt s kt hp ca nhng phng php ny. Gi tr kt qu LQI c giao cho tng mng v tng ng dng x l.
1.2.3. Ch s nh gi knh truyn (CCA):
CCA c s dng xem xem khi no mt knh truyn c coi l ri hay bn. C ba phng php thc hin vic kim tra ny:
CCA 1 : Nng lng vt ngng. CCA s thng bo knh truyn bn trong khi d ra bt k nng lng no vt ngng ED.
CCA 2 : Cm bin sng mang. CCA thng bo knh truyn bn ch khi nhn ra tn hiu c c tnh tri ph v iu ch ca IEEE802.15.4. Tn hiu ny c th thp hoc cao hn ngng ED.
CCA 3 : Cm bin sng mang kt hp vi nng lng vt ngng. CCA s bo knh truyn bn ch khi d ra tn hiu c c tnh tri ph v iu ch ca IEEE 802.15.4 vi nng lng vt ngng ED.
2. Tng iu khin d liu MAC
Tng iu khin mi trng truy nhp MAC cung cp 2 dch v l dch v d liu
MAC v qun l MAC. Nhim v ca tng MAC l qun l vic pht thng tin bo
hiu beacon, nh dng khung tin truyn i trong mng, iu khin truy nhp knh,
qun l khe thi gian GTS, iu khin kt ni v gii phng kt ni, pht khung Ack
2.1. Cu trc siu khung :
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Hnh 10: Cu trc siu khung.
LR-WPAN cho php s dng theo nhu cu cu trc siu khung. nh dng ca siu khung c nh r bi PAN coordinator. Mi siu khung c gii hn bi tng mng v c chia thnh 16 khe nh nhau. Ct mc bo hiu d ng beacon c gi i trong khe u tin ca mi siu khung. Nu mt PAN coordinator khng mun s dng siu khung th n phi dng vic pht mc beacon. Mc ny c nhim ng b cc thit b nh km, nhn dng PAN v cha ni dung m t cu trc ca siu khung.
Siu khung c 2 phn hot ng v ngh. Trong trng thi ngh th PAN coordinator khng giao tip vi cc thit b trong mng PAN, v lm vic mode cng sut thp. Phn hot ng gm hai giai on : giao on tranh chp truy cp (CAP) v giai on tranh chp t do (CFP), giai on tranh chp trong mng chnh l khong thi gian tranh chp gia cc trm c c hi dng mt knh truyn hoc ti nguyn trn mng. Khong thi gian tn ti ca cc phn khc nhau ca siu khung c nh ngha bi gi tr ca macBeaconOrder v macSuperFrameOrder. Trong macBeaconOrder m t khong thi gian m b iu phi coordinator truyn khung bo hiu tm ng. Khong thi gian gia hai mc beacon c quan h ti macBeaconOrder theo biu thc sau:
BI = aBaseSuperFrameDuration*2BO
symbol (vi 0 BO14)
Gi tr ca macSuperFrameOrder cho bit di ca phn tch cc ca siu
khung. Khong thi gian siu khung c quan h macSuperFrameOrder theo biu thc
sau:
SD = aBaseSuperFrameDuration*2SO
symbol
Phn tch cc ca mi siu khung c chia thnh 3 phn CAP,CFP v beacon.
Mc beacon c pht vo u khe s 0 m khng cn s dng CSMA.
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2.1.1. Khung CAP :
CAP c pht ngay sau mc beacon v kt thc trc khi pht CFP. Nu di
ca phn CFP = 0 th CAP s kt thc ti cui ca siu khung. CAP s c ti thiu
aMinCAPLength symbols tr trng hp phn khng gian thm vo c dng
iu chnh vic tng di ca khung beacon vn c th duy tr c GTS v iu
chnh linh ng tng hay gim kch thc ca CFP.
Tt c cc khung tin ngoi tr khung Ack v cc khung d liu pht ngay sau
khung Ack trong lnh yu cu, m chng c pht trong CAP s s dng thut ton
CSMA-CA truy nhp knh. Mt thit b pht trong khong thi gian phn CAP kt
thc s khong thi gian IFS trc khi ht phn CAP. Nu khng th kt thc c th
thit b ny s tr hon vic pht cho n khi CAP ca khung tip theo c pht.
Khung cha lnh iu khin MAC s c pht trong phn CAP.
2.1.2. Khong cch gia hai khung (IFS):
Khong thi gian IFS l thi gian cn thit tng PHY x l mt gi tin nhn c. Khung tin c truyn theo ch k IFS, trong di ca chu k IFS ph thuc vo kch thc ca khung va c truyn i. Khung c di ph thuc vo aMaxSIFSFrameSize s tun theo chu k SIFS (l khong thi gian ti thiu aMinSIFSPeriod symbols), v cc khung c di ln hn aMaxSIFSFrameSize s tun theo chu k LIFS(l khong thi gian ti thiu aMinLIFSPeriod symbols).
Hnh 11.
2.2. Thut ton a truy nhp s dng cm bin sng mang CSMA-CA:
y l phng php truy nhp mng dng cho chun mng khng dy IEEE
802.15.4.Cc thit b trong mng s lin tc lng nghe thng bo trc khi truyn, tt
c cc thit b u c quyn truy cp nh nhau khi ng truyn ri. Trn cc mng
ln, thi gian truyn t u cp ny n u kia l mt trm c th truy cp n
cp ngay c khi c mt trm khc va truy cp ti.
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Hnh 12: Lu thut ton.
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Thut ton truy nhp knh CSMA-CA c s dng trc khi pht d liu hoc
trc khi pht khung tin MAC trong phn CAP. Nu bn tin bo hiu c s dng
trong mng PAN th thut ton CSMA-CA gn khe thi gian c dng, ngc li
thut ton CSMA-CA khng gn khe thi gian s c s dng. Trong c hai trng
hp thut ton u c b xung bng cch s dng khi thi gian backoff bng vi
thi gian ca tham s aUnitBackoffPeriod. Trong thut ton truy nhp knh CSMA-
CA gn khe thi gian, bin ca khong thi gian backoff ca mi thit b trong mng
PAN c sp xp thng hng vi bin ca khe siu khung trong thit b iu phi
mng PAN.
Mi thit b cha 3 bin s :NB, BW v BE. Trong NB l s ln m thut ton
ny b yu cu rt li trong khi ang c gng truyn, gi tr ban u ca n l 0. Bin
CW l di ca ca s tranh chp, n cho bit khong thi gian cn thit lm sch
knh truyn trc khi pht, gi tr ban u ca n l 2 trc khi c gng pht v quay
tr li 2 khi knh truy nhp b bn. Bin s BE cho bit mt thit b phi ch bao lu
c th truy nhp vo mt knh
Trong thut ton CSMA-CA gn khe thi gian, NB, CW, BE c thit lp trc,
bin ca khong thi gian backoff k tip cng c xc nh trc. Tng MAC s tr
ngu nhin trong phm vi 0 n 2*BE-1 sau yu cu tng PHY thc hin nh gi
knh truy nhp xem l ri hay bn. Nu knh truyn bn, tng MAC s tng NB v BE
ln 1, nhng cng lun m bo gi tr ny nh hn aMaxBE. Nu gi tr ca NB nh
hn hoc bng gi tr tham s macMaxCSMABackoffs th s thng bo li truy nhp
knh.
2.3. Cc m hnh truyn d liu:
Da trn cu trc mng WPAN th ta c th phn ra lm ba kiu, ba m hnh
truyn d liu: t thit b iu phi mng PAN coordinator ti thit b thng, t thit
b thng ti thit b iu phi mng PAN coordinator, v gia cc thit b cng loi.
Nhng nhn chung th mi c ch truyn u ph thuc vo vic l kiu mng c
h tr vic pht thng tin thng bo beacon hay khng.
Khi mt thit b mun truyn d liu trong mt mng khng h tr vic pht beacon, khi th n ch n gin l truyn khung d liu ti thit b iu phi bng cch s dng thut ton khng gn khe thi gian. Thit b iu phi Coordinator tr li bng khung Ack nh hnh13
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Hnh 13. Lin lc trong mng khng h tr beacon
Khi mt thit b mun truyn d liu ti thit b iu phi trong mng c h tr beacon. Lc u n s ch bo hiu beacon ca mng. Khi thit b nhn c bo hiu beacon, n s s dng tn hiu ny ng b cc siu khung. ng thi, n cng pht d liu s dng phng php CSMA-CA gn khe thi gian v kt thc qu trnh truyn tin bng khung tin xc nhn Ack.
Hnh 14. lin lc trong mng c h tr beacon.
Cc ng dng truyn d liu c iu khin hon ton bi cc thit b trong mng PAN hn l c iu khin bi thit b iu phi mng. Chnh kh nng ny cung cp tnh nng bo ton nng lng trong mng ZigBee. Khi thit b iu phi mun truyn d liu n mt thit b khc trong loi mng c h tr pht beacon, khi n s ch th trong thng tin bo hiu beacon l ang truyn d liu. Cc thit b trong mng lun lun lng nghe cc thng tin bo hiu beacon mt cch nh k, khi pht hin ra c d liu lin quan ti n ang c truyn, n s pht lnh yu cu d liu ny, cng vic ny s dng slotted CSMA-CA. Cng vic ny c m t bng hnh14 , trong hnh ny th khung tin Ack ca thit b iu phi cho bit rng gi tin c truyn thnh cng, vic truyn gi tin s dng k thut gn khe thi gian CSMA-CA, khung Ack thit b thng tr li l nhn gi tin thnh cng. Vo lc nhn khung
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tin Ack t thit b thng th bn tin s c xa khi danh sch bn tin trong thng tin bo hiu beacon.
Hnh15. Kt ni trong mng h tr beacon
Trong trng hp mng khng h tr pht beacon thit b iu phi mun truyn d liu ti cc thit b khc, n s phi lu tr d liu cho thit b lin quan c th yu cu v tip xc vi d liu . Thit b c th tip xc c vi d liu lin quan n n bng cch pht i lnh yu cu d liu ti thit b iu phi, s dng thut ton khng gn khe thi CSMA-CA. Nu d liu ang c truyn, th thit b iu phi s pht khung tin bng cch s dng thut ton khng gn khe thi gian CSMA-CA, nu d liu khng c truyn th thit b iu phi s pht i khung tin khng c ni dung ch ra rng d liu khng c pht.
Hnh 16. kt ni trong mng khng h tr pht beacon.
Ni chung trong mng mt li, tt c cc thit b u bnh ng v c kh nng kt ni n bt k thit b no trong mng min l thit b nm trong bn knh ph sng ca n. C hai cch thc hin vic kt ni. Cch th nht l nt trong mng lin tc lng nghe v pht d liu ca n i bng cch s dng thut tan khng gn khe thi gian CSMA-CA. Cch th hai l cc nt t ng b vi cc nt khc c th tit kim c nng lng.
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TNG QUAN V CNG NGH ZIGBEE
17 | P a g e
2.4. Pht thng tin bo hiu beacon:
Mt thit b FFD hot ng trong ch khng pht thng tin bo hiu hoc c th
pht thng tin bo hiu ging nh l thit b iu phi mng. Mt thit b FFD khng
phi l thit b iu phi mng PAN c th bt u pht thng tin bo hiu beacon ch
khi n kt ni vi thit b iu phi PAN. Cc tham s macBeaconOrder v
macSuperFrameOrder cho bit khong thi gian gia hai thng tin bo hiu v
khong thi gian ca phn hot ng v phn ngh. Thi gian pht bo hiu lin trc
c ghi li trong tham s macBeaconTxTime v c tnh ton gi tr ca tham s
ny ging nh gi tr trong khung thng tin bo hiu beacon.
2.5. Qun l v phn phi khe thi gian m bo GTS:
Khe thi gian m bo GTS cho php mt thit b c th hot ng trong mt knh
truyn bn trong mt phn ca siu khung dnh ring cho thit b . Mt thit b ch
c th chim v s dng mt khe thi gian khi m thit b lin quan n thng tin
bo hiu beacon hin thi lc . Thit b iu phi mng PAN c th chim hu khe
thi gian GTS v s dng khe thi gian ny lin lc vi cc thit b khc trong
mng. Mt khe thi gian n c th ko di hn thi gian ca siu khung. Thit b
iu phi mng PAN c th chim hu ti by khe thi gian GTS cng mt lc min
l n c thm quyn trong siu khung.
Mt khe thi gian c th c chim hu trc khi s dng nu c s yu cu ca
thit b iu phi mng PAN. Tt c cc khe thi gian GTS u c t lin nhau
cui ca siu khung sau phn CAP, v hot ng theo c ch FCFS (first-come-first-
serve) n trc dng trc. Mi khe thi gian GTS c th c gii phng nu khng
c yu cu no, v mt khe thi gian GTS c th c gii phng vo bt k lc no
khi thit b chim hu n khng dng na.
Ch duy nht thit b iu phi PAN mi c quyn qun l khe thi gian. qun
l mi khe thi gian m bo, thit b iu phi c th lu tr khe bt u, di,
phng hng (thu hay pht) v a ch thit b kt ni.
Mi thit b trong mng c th yu cu mt khe thi gian pht hay mt khe thi
gian thu. chim hu c mt khe thi gian th thit b phi lu tr thng tin
khe bt u, di v phng hng. Nu mt thit b c cp pht mt khe thi
gian GTS thu, n s c ton quyn s dng trn vn khe thi gian nhn d liu.
Tng t nh vy thit b iu phi mng PAN cng c th c ton quyn s dng
trn vn khe thi gian nhn liu khi c mt thit b khc chim khe thi gian
pht.
Mt thit b yu cu chim hu khe thi gian mi thng qua lnh yu cu GTS vi
cc tnh cht ( di, thu hay pht?,) thit lp theo yu cu ng dng. xc nhn
lnh ny th thit b iu phi s gi mt khung tin Ack. Sau khi pht khung tin Ack
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TNG QUAN V CNG NGH ZIGBEE
18 | P a g e
th thit b iu phi s kim tra kh nng hin thi ca siu khung da trn di ca
phn CAP v di khe thi gian GTS c yu cu. Siu khung s sn sng nu
di khe thi gian GTS khng lm gim di ca phn CAP i qu di nh nht
ca CAP c qui inh trong tham s aMinCAPLength. Thit b iu phi mng PAN
thc hin quyt nh ca n bn trong siu khung aGTSDescPersistenceTime. Trong
khi xc nhn gi tin Ack t thit b iu phi th thit b ny vn tip tc theo di
thng tin bo hiu v ch siu khung aGTSDescPersistenceTime. Khi thit b iu
phi quyt nh xem xem n c sn sng cho yu cu GTS khng, n s pht i m t
v GTS vi chi tit yu cu v on ngn a ch ca thit b yu cu. N s ch ra
di v khe GTS u tin trong siu khung ri thng bo cho tng trn v vic cp pht
khe GTS mi ny. Nu sau khi kim tra m thy kh nng ca siu khung l khng
cp pht theo yu cu v GTS, th khe u tin s c nh s 0 ti di khe
GTS ln nht c th cung cp c hin thi. Nhng m t v GTS s c gi trong
khung tin bo hiu beacon cho aGTSPersistenceTime. Trong khi xc nhn khung tin
bo hiu beacon, thit b s x ly v thng bo ln tng trn.
Tng t nh khi yu cu cp pht GTS, mt thit b cho bit n yu cu c gii phng s chim hu GTS thng qua lnh yu cu gii phng vi cc thng s ca GTS ang tn ti. Sau th khe thi gian ny s c t do. Thit b iu phi PAN phi m bo rng khng c khong trng no xut hin trong CFP khi gii phng khe thi gian GTS, di maximum CAP nh th m c tng ln ( tng ng bng di ca khe thi gian oc gii phng).
Thc th qun l tng MAC (MLME) ca thit b iu phi mng PAN c nhim v pht hin khi mt thit b dng s dng khe thi gian GTS. Cng vic thc hin bng nguyn tc sau. i vi khe GTS pht, MLME s cng nhn mt khe thi gian GTS c gii phng nu khung d liu khng c nhn trong ti thiu 2*n siu khung. i vi khe GTS thu, MLME s cng nhn thit b khng cn s dng GTS na nu khung tin xc nhn Ack khng c nhn trong ti thiu 2*n siu khung.
82 , if 0 8;
1 , if 9 14;
macBeaconOrdern macBeaconOrder
n macBeaconOrder
2.6. nh dng khung tin MAC.
Mi khung bao gm cc thnh phn sau:
u khung MHR(MAC header): gm cc trng thng tin v iu khin khung
tin, s chui, v trng a ch
Ti trng khung (MAC payload) : cha cc thng tin chi tit v kiu khung.
Khung tin ca bn tin xc nhn Ack khng c phn ny.
Cui khung MFR(MAC footer) cha chui kim tra khung FCS (frame check
sequence)
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TNG QUAN V CNG NGH ZIGBEE
19 | P a g e
Hnh 17. nh dng khung MAC
3. Tng mng ca ZigBee/IEEE802.15.4:
3.1. Dch v mng:
Tng vt l trong m hnh ca giao thc ZigBee c xy dng trn nn ca tng
iu khin d liu, nh nhng c im ca tng MAC m tng vt l c th ko di
vic a tin, c th m rng c qui m mng d dng, mt mng c th hot ng
cng cc mng khc hoc ring bit. Tng vt l phi m nhn cc chc nng nh l:
Thit lp mt mng mi.
Tham gia lm thnh vin ca mt mng ang hot hoc l tch ra khi mng
khi ang l thnh vin ca mt mng no .
Cu hnh thit b mi nh h thng yu cu, gn a ch cho thit b mi tham
gia vo mng.
ng b ha cc thit b trong mng c th truyn tin m khng b tranh
chp, n thc hin ng b ha ny bng gi tin thng bo beacon.
Bo mt: gn cc thng tin bo mt vo gi tin v gi xung tng di
nh tuyn, gip gi tin c th n c ng ch mong mun. C th ni
rng thut ton ca ZigBee l thut ton nh tuyn phn cp s dng bng
nh tuyn phn cp ti u c p dng tng trng hp thch hp.
3.2. Dch v bo mt:
Khi khung tin tng MAC cn c bo mt, th ZigBee s dng dch v bo mt
ca tng MAC bo v cc khung lnh MAC, cc thng tin bo hiu beacon, v cc
khung tin xc nhn Ack. i vi cc bn tin ch phi chuyn qua mt bc nhy n,
tc l truyn trc tip t nt mng ny n nt mng ln cn ca n, th ZigBee ch
cn s dng khung tin bo mt MAC m ha bo v thng tin. Nhng i vi cc
bn tin phi chuyn gin tip qua nhiu nt mng mi ti c ch th n cn phi
nh vo tng mng lm cng vic bo mt ny. Tng iu khin d liu MAC s
dng thut tan AES (chun m ha cao cp). Ni chung th tng MAC l mt qu
trnh m ha, nhng cng vic thit lp cc kha key, ch ra mc bo mt, v iu
khin qu trnh m ha th li thuc v cc tng trn. Khi tng MAC pht hoc nhn
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TNG QUAN V CNG NGH ZIGBEE
20 | P a g e
mt khung tin no c bo mt, u tin n s kim tra a ch ch hoc ngun
ca khung tin , tm ra ci kha kt hp vi a ch ch hoc a ch ngun, sau
s dng ci kha ny x l khung tin theo qui trnh bo mt m ci kha qui
nh. Mi kha key c kt hp vi mt qui trnh bo mt n l. u mi khung
tin ca MAC lun c 1 bit ch r khung tin ny c c bo mt hay khng.
Khi pht mt khung tin, m khung tin ny yu cu cn c bo ton nguyn vn.
Khi phn u khung v phn ti trng khung MAC s tnh tan cn nhc to ra
mt trng m ha tin nguyn vn (MIC- Message Integrity) ph hp, MIC gm
khong 4,8 hoc 16 octets. MIC s c gn thm vo bn phi phn ti trng ca
MAC.
Hnh18. Khung tin m ha tng MAC.
Khi khung tin pht i i hi phi c tin cy cao, th bin php c s dng
m ha thng tin l s chui v s khung s c gn thm vo bn tri phn ti trng
khung tin MAC. Trong khi nhn gi tin, nu pht hin thy MIC th lp tc n s kim
tra xem khung tin no b m ha gii m. C mi khi c mt bn tin gi i th thit
b pht s tng s m khung ln v thit b nhn s theo di cn c vo s ny. Nh
vy nu nh c mt bn tin no c s m khung tin b nhn dng mt ln th thit
b nhn s bt c bo li bo mt. B m ha ca tng MAC da trn ba trng thi ca
h thng.
bo m tnh nguyn vn: M ha s dng AES vi b m CTR
bo m tnh tinh cy : M ha s dng AES vi chui khi m CBC-MAC
m bo tnh tin cy cng nh nguyn vn ca bn tin th kt hp c hai trng
thi CTR v CBC-MAC trn thnh trng thi CCM.
Tng mng cng s dng chun m ha AES. Tuy nhin khc vi tng iu khin
d liu MAC, b m ha ca tng mng lm vic da trn trng thi CCM* ca h
thng. Trng thi ny thc cht l s ci bin t CCM ca tng MAC, n thm vo
chun m ha ny cc chc nng l ch m ha tnh tin cy v ch m ha tnh nguyn
vn. S dng CCM* gip lm n gin ha qu trnh m ha d liu ca tng mng,
cc chui m ha ny c th dng li kha key ca chui m ha khc. Nh vy th
kha key ny khng hon ton cn l ranh gii ca cc chui m ha na. Khi tng
mng pht hoc nhn mt gi tin c m ha theo qui c bi nh cung cp dch v,
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TNG QUAN V CNG NGH ZIGBEE
21 | P a g e
n s kim tra a ch ngun hoc ch ca khung tin tm ra kha key lin quan ti
a ch , sau s p dng b m ha ny gii m hoc m ha cho khung tin.
Tng t nh qu trnh m ha tng MAC, vic iu khin qu trnh m ha ny c
thc hin bi cc tng cao hn, cc s m khung v MIC cng c thm vo m
ha khung tin.
Hnh 19. Khung tin m ha tng mng.
4. Tng ng dng ca ZigBee/IEEE 802.15.4:
Lp ng dng ca ZigBee/IEEE 802.15.4 thc cht gm cc ba tng nh hnh v trn,
cc tng ny tng ng vi cc tng phin, trnh din v ng dng trong m hnh 2.1
OSI 7 tng.
Trong ZigBee/IEEE 802.15.4 th chc nng ca tng Application Framework l:
D tm ra xem cc nt hoc thit b no khc ang hot ng trong vng ph
sng ca thit b ang hot ng hay khng.
Duy tr kt ni, chuyn tip thng tin gia cc nt mng.
Chc nng ca tng Application Profiles l:
Xc nh vai tr ca cc thit b trong mng. (thit b iu phi mng, hay thit
b u cui, FFD hay RFD)
Thit lp hoc tr li yu cu kt ni.
Thnh lp cc mi quan h gia cc thit b mng.
Chc nng ca tng Application l thc hin cc chc nng do nh sn xut qui nh
(giao din...) b sung thm vo cc chc nng do ZigBee quy nh.
III. ng dng:
Mt vi nm gn y Vit Nam ang bt u a cng ngh ZigBee vo cc h thng o lng hin i, to ra cc mng iu khin khng dy th h mi. C th nu mt vi v d minh ha cho vic ng dng cng ngh ny trong mc ch thu thp v truyn s liu:
H thng o lng, iu khin cp nhin liu:
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TNG QUAN V CNG NGH ZIGBEE
22 | P a g e
H thng bao gm module thu/pht Zigbee XBee-PRO ZB lp trnh c, Gateway v PC gim st vic cung cp nhin liu, sn lng bm ra ca cc ct bm v p lun gi thnh quy nh trnh tht thot, m bo chnh xc, cht lng dch v.
Mng truyn thng khng dy s dng cc thit b ca hng DIGI/M hat ng trn di tn 2.4GHz, khong cch t 30 n 100m, u vo ADC 10bit. H thng gm cc chc nng: o lng mc xng du trong cc b cha, gi s liu o qua module ZigBee v trung tm. Thu thp s liu lng nhin liu bm ra t cc ct bm, truyn d liu theo mng khng dy v trung tm. Phn mm trn my tnh ti trung tm s tnh ton lng nhin liu tiu th, gi thnh sn phm, thng k, bo co s lng nhin liu trong b cha. Khi cc ct bm c tch hp thm u c th, cc tn hiu iu khin t trung tm s gi ti cc ct bm kim tra ti khon ca khch hng ng thi cho php s lng nhin liu cung cp.
Hnh 20: M hnh mng o lng iu khin khng dy ng dng cng ngh ZigBee trong h thng trm bm nhin liu
H thng o lng mi trng:
H thng o nhit , m s dng trong vic kim tra mi trng i vi cc bung, phng c yu cu cn phi bo qun cc thit b chu nh hng bi thng s nhit / m nh: bo qun dc liu, kho tng, phng th nghim,....Vi mi thit b o gm 2 sensor o nhit v m, s c chip Zigbee v PIC m nhn vic thu d liu, Chip ny s truyn d liu v 1 chip Zigbee khc trn board trung tm. Board ny l Zigbee Coordinator c kt ni USB vi my tnh. My tnh s hin th s liu
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TNG QUAN V CNG NGH ZIGBEE
23 | P a g e
bng 1 phn mm, ng thi truyn lnh iu khin, cnh bo ti cc thit b khc trong h thng qua cc b thu/pht khng dy. C th s dng cc module Wireless 2.4Ghz h tr Zigbee chun IEEE 802.15.4 do hng Microchip sn xut l MRF24J40MA, MRF24J40MB v chip RF MRF24J40.
Vic s dng mng truyn thng khng dy ZigBee trong cc h thng o lng iu khin nhm thay th cc mng c dy trc y tit kim c ng k s lng dy dn, cng vic thi cng, bo tr, bo dng, cng nh nng cp, m rng cc nt mng.
CHNG II: TM HIU PHN CNG B KIT PHT TRIN CA ZIGBEE
I. S dng phn cng.
Cc phn cng trong cc b c th c s dng trong hai ch khc nhau. C th
kt ni trc tip n CC2520EM SmartRF05EB (hnh 7) hoc kt ni EM n
CCMSP-EM v sau kt ni lp rp ny cho EB (hnh 8).
Ty chn u tin (Hnh 7) nn c s dng khi RF Module c iu khin bi
SmartRF Studio thng qua b iu khin USB trn SmartRF05EB. N cng c th
thc hin phn mm chy trn vi iu khin (CC2511) trn SmartRF05EB kim
sot EM trc tip.
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TNG QUAN V CNG NGH ZIGBEE
24 | P a g e
Trng hp th hai (hnh 8) c th c s dng khi cc m-un RF s c iu
khin bi MSP430 trn bng CCMSP-EM430F2618.
Lu rng n c th vn hnh CC2520EM + CCMSP-EM c lp (tc l khng EB),
nhng iu ny i hi mt s loi in bn ngoi. Hnh 9 cho thy CC2520EM kt
ni vi hi ng qun tr MCU nh mt n v c lp. Hi ng qun tr c th c
h tr thng qua cc MSPFET430UIF bng cch thit lp chuyn i thch hp trn
din n. Xem chng 8 bit chi tit. Cc b pht trin i km vi hai CCMSP
EM430F2618 cho php hai nt hon chnh th nghim peer-to-peer lin kt v th
nghim giao thc n gin. Phn cng b sung (SmartRF05EB + CC2520EM) c th
c s dng cho mc ch g li, v d nh gi sniffing hoc chp v / hoc chn cc
gi tin s dng SmartRF Studio.
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TNG QUAN V CNG NGH ZIGBEE
25 | P a g e
1. S dng SmartRF Studio vi SmartRF05EB v CC2520EM.
s dng cc SmartRF Studio cc CC2520EM c kt ni trc tip n
SmartRF05EB, nh th hin trong hnh di y.
Sau khi ci t ca SmartRF Studio v cm EB vi my tnh qua cng USB, ngi li
xe c th c ci t nh m t trong chng 5.2. Khi bt u SmartRF Studio, ca
s sau s xut hin:
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TNG QUAN V CNG NGH ZIGBEE
26 | P a g e
Hy chc chn rng bn chn tab gi l SmartRF 05 DK. Hi ng qun tr nh gi
kt ni s c lit k, cho thy mt CC2520 c sn. Nhp p chut vo mc, v mt
ca s mi s xut hin.
y l bng iu khin chnh cho CC2520 t SmartRF Studio. N cho php bn thc
hin mt nNumber iu:
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TNG QUAN V CNG NGH ZIGBEE
27 | P a g e
Chy ch th nghim TX th nghim ca RF sn lng in v quang
ph. Kt ni mt my phn tch ph hoc mt ng h in kt ni
CC2520EM SMA thc hin cc php o RF.
Chy gi TX v RX kim tra. i vi th nghim ny, bn nn c hai EBS vi
CC2520EMs kt ni vi my tnh.
o Kch p vo c hai thit b trong danh sch, m hai ca s, cho kim
sot ca hai radio cng mt lc.
o Chn mt l ngi nhn v ngi kia l my pht.
o Trn ngi nhn, chn "gi RX" tab.
o Thit lp cc thng s th nghim c bn v bm nt "Bt u gi RX".
o Trn my pht, chn "gi TX" tab.
o Bt u truyn bng cch nhn nt "Bt u gi TX".
o Ca s trng thi s hin th s lng cc gi tin gi / nhn v cng
tn hiu hin ti.
Ngoi ra, bn c th c ng dng ca bn v kim tra thng xuyn RX ca
bn bng cch nhn c mt gi tin c gi bi mt i pht thanh iu
khin bi SmartRF Studio - hoc kim tra TX thi quen ca bn bng cch s
dng SmartRF Studio nhn cc gi tin c gi bi ng dng ca bn.
c v / hoc sa i ng k v ci t thng thng, chng hn nh RF tn
s (hoc knh) v sn lng in.
Hng dn s dng SmartRF Studio c thm chi tit.
2. Chy V d phn mm ng dng.
Ban CCMSP-EM n lp trnh trc vi mt gi gi Li (PER) ng dng th nghim,
lm cho n c th v d nh thc hin kim tra phm vi n gin ra khi hp.
Chy ng dng th nghim PER:
1. Lp rp phn cng nh c m t trong hnh 8 trn. Nh kt ni cc
ng-ten.
2. Chn mt ngun nng lng thch hp. Ban c th ly ngun thng qua cp
USB, bng cch s dng mt ngun DC hoc bng cch s dng pin 2xAA.
Hy chc chn rng la chn in nhy P11 chn ngun nng lng thch
hp (ng v tr cho pin, li cho in USB hoc ngun DC). Xem chi tit
trong phn 7.3.
3. in c bt bng cch chuyn v tr ca cng tc ngun chnh t OFF
sang ON.
4. Thc hin theo cc hng dn trn mn hnh LCD bng cch s dng phm
iu khin chn ch v thit lp mt nt nh my pht v mt l nhn.
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TNG QUAN V CNG NGH ZIGBEE
28 | P a g e
5. Khi th nghim bt u, n s hin th mt gi tr PER v mt gi tr RSSI
trn mn hnh LCD vo nt nhn.
chng trnh MSP430 MCU trn bng CCMSP-EM430F2618 cc
MSPFET430UIF (FET) l cn thit. Kt ni cc FET JTAG ni P12 trn
CCMSPEM430F2618 v mt my tnh bng cp USB. S dng IAR Embedded
Workbench cho MSP430 ti v v g li.
Hng dn ngi s dng CC2520 phn mm c chi tit v cc v d phn mm c
sn.
M ngun y cho cc v d phn mm c th c ti v t trang web CC2520DK
(www.ti.com/cc2520dk).
Cng vui lng truy cp trang web Timac (www.ti.com / Timac) cho mt hon 802.15.4
ph lp MAC cho MSP430F2618 v nn tng CC2520.
II. th nghim RF
Kim tra RF c thc hin tt nht bng cch s dng SmartRF Studio cng vi Kit
pht trin. Kt ni vi mt my tnh SmartRF05EB s dng giao din USB. Bt u
SmartRF Studio v chn tab SmartRF05DK. Chn hi ng qun tr nh gi vi
CC2520EM (mt s hi ng c th c kt ni vi mt my tnh cng mt lc) - n
s c lit k l "CC2520 - thit b mi" - v nhp vo nt bt u. Trong ci t ca
s SmartRF Studio chnh c th c thay i, kim tra thc hin v ng k iu
chnh. Thit b o lng RF c th c kt ni vi u ni SMA trn EM.
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TNG QUAN V CNG NGH ZIGBEE
29 | P a g e
Xin vui lng xem ti liu SmartRF Studio bit thm thng tin v cch s dng cng
c ny.
1. Kim tra in u ra.
Thay v kt ni mt ng-ten kt ni SMA trn EM nh, kt ni cp ng trc 50
Ohm trc tip n mt my phn tch ph. S dng "TX Ch kim tra"1 chc nng
trong SmartRF Studio thit lp cc chip pht ra mt tn hiu tn s mong
mun.
Bng cch s dng RF cp cht lng tt, s mt mt trong cc h thng cp nn
khng ng k. Tuy nhin chc chn rng my phn tch ph c hiu chnh. Nu c
th, hy kim tra n chng li mt cng c hiu chnh nh mt my pht tn hiu RF.
Phn tch quang ph cha c hiu chnh c th hin th cc li ca mt s DBS.
2. T l li gi (PER) th nghim.
S PER l t l gia s lng cc gi tin b mt v tng s cc gi tin c gi i.
PER lin quan n truyn thng Li Bit Rate (BER) thng qua cc cng thc
Ngng nhy cm ca cc i pht thanh l cng tn hiu u vo thp nht m ti
ngi nhn c th gii m cc tn hiu vi mt mc hp l ca tnh ng n .
Thng thng, mt PER 1 % c s dng nh l gii hn xc nh ngng nhy
cm.
N c th thc hin th nghim thc t vi phm vi ng dng th nghim PER c
lp trnh trc trn bng CCMSP - EM430F2618 . t my pht ti mt a im c
nh v t cc my thu mt khong cch nht nh t my pht . Sau chy th
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TNG QUAN V CNG NGH ZIGBEE
30 | P a g e
nghim PER o lng li gi v c th l cng tn hiu . Lp li nhng
khong cch khc nhau c c mt tng v phm vi c th t c .
Bng cch thm mt gy nhiu ( mt nt th ba m to ra ting n hoc trn cng mt
knh hoc mt tn hiu mnh m trn mt knh ln cn ) n cng c th o t chi
ng knh v chn lc / chn hiu sut.
Cng ng dng th nghim PER c th c s dng o nhy n gin vi
CC2520EM v / hoc vi phn cng nguyn mu ca ring bn. Trong trng hp ny
, kt ni cc n v bn mun th nghim vi mt my pht tt c bit n vi cc
loi cp ng trc v suy hao . Thm suy hao cho n khi gi tr PER l 1%. Cng
tn hiu pha ngi nhn l sau gii hn nhy ca h thng.
bit thm chi tit v th nghim nhy cm , vui lng tham kho " DN002 -
Kim tra nhy thc t " ( www.ti.com/lit/swra097 ) .
III. RF05EB thng minh.
SmartRF05EB l bo mch ch trong h thng, lu tr tt c cc giao din v kt ni
ngi s dng giao din bn ngoi.
Hnh sau cho thy cc thnh phn chnh ca hi ng qun tr v phc tho cc bus
thng tin lin lc chnh.
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TNG QUAN V CNG NGH ZIGBEE
31 | P a g e
Cc thnh phn chnh trn tu l b iu khin USB. N giao tip vi my tnh qua
cng USB v chuyn cc yu cu t cc cng c my tnh khc nhau (v d nh
SmartRF Studio, SmartRF flash trnh) hnh ng trn din n.
B iu khin USB giao tip vi cc m-un nh gi s dng SPI hoc UART.
Lu rng khng phi tt c cc thit b ngoi vi trn bng c th truy cp t b iu
khin USB. N c quyn truy cp vo giao din RS232 UART, LCD, LED mt (D6),
phm iu khin v mt nt (nt USB). Ngha l n khng c quyn truy cp vo n
flash ni tip trn din n.
Cc m-un kt ni vi cng EM c kh nng truy cp vo tt c cc thit b ngoi
vi EB. N c th truy cp vo mn hnh LCD, n flash ni tip, bn n LED, 2 nt,
phm iu khin v giao din UART RS232.
V nhiu thit b ngoi vi c th c truy cp t c hai b iu khin USB v cc
MCU EM, mt s chn I / O c kh nng c th c iu khin bi hai ngun khc
nhau. Phn vng tiu chun chy trn b iu khin USB x l ny bng cch thit lp
tt c cc chia s I / O trong ba trng thi (tr khng cao) v do trnh c xung
t.
1. USB MCU.
MCU USB l CC2511F32 ca Texas Instruments. N thc s l mt Low Power
Wireless System-on-chip bao gm mt nh nc-of-the-art 2.4 GHz, 32 MB trong h
thng lp trnh flash, 4 MB RAM, 12 bit ADC, tnh gi v mt b iu khin USB.
Xin vui lng xem www.ti.com/cc2511 thng tin chi tit v b iu khin ny.
1.1. B np khi ng v phn mm tiu chun.
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TNG QUAN V CNG NGH ZIGBEE
32 | P a g e
B iu khin USB c lp trnh vi mt b np khi ng khi n c vn chuyn
t nh my. B np khi ng cho php lp trnh m mi vo MCU USB thng qua
cp USB (tc l khng c lp trnh thm hay phn cng cn thit). B np khi ng
giao tip vi SmartRF Studio hoc SmartRF flash Lp trnh.
Khi b iu khin USB bt u chy, n s kim tra cho mt phin bn ca phn mm
hp l trong flash. Nu pht hin mt ng dng hp l, b np khi ng khi ng
phn mm v cedes kim sot ca b iu khin.
Phn vng tiu chun c s dng kim sot RF EM v giao tip vi cc ng
dng chy trn my tnh thng qua cng USB.
Cp nht firmware c thc hin t ng bi SmartRF Studio nu pht hin mt
phin bn phn mm c v / hoc khng tng thch trn b iu khin. SmartRF
Studio v SmartRF flash trnh cng cho php lp trnh hng ca phn mm. Vui lng
tham kho hng dn ca ngi dng tng ng c hng dn chi tit.
N cng c th cp nht firmware v b np khi ng trn bng bng cch s dng
giao din g li ca b iu khin USB. V y l mt CC2511 , s dng mt
SmartRF04EB2 chng trnh iu khin . Kt ni mt cp phng 10-pin cho "Ext
SoC Debug" cm (P3) trn SmartRF04EB v "USB Debug" cm (P2) trn
SmartRF05EB . S dng SmartRF flash lp trnh lm chng trnh thc t .
Lu rng c mt cch buc cc b np khi ng khng bt u phn vng . t
cng tc la chn ch EB v tr CC2511JOYSTICK v di chuyn phm iu khin
trong bt k hng no (tr v tr trung tm ) . Khi hi ng qun tr c bt, cc
phn mm khng c bt u v b np khi ng s c quyn kim sot ca hi
ng qun tr . LED D6 s c nhp nhy vi mt khong thi gian 1 giy , ch ra
rng b np khi ng ang chy. S dng phng php ny kim tra xem bn c
mt b np khi ng lm vic hay khng.
Nu D6 LED nhp nhy vi tn s nhanh hn ( 10 ln mi giy ) b np khi ng
khng th tm thy mt ng dng hp l khi ng.
LED cng s c khi firmware ang chy (ch OK) .
Khi b np khi ng ang chy, cc chc nng ch c cung cp t SmartRF Studio
v SmartRF flash Lp trnh l ti mt phin bn mi ca phn mm tiu chun.
1.2. USB MCU pin ra.
Bng sau y cho thy vic s dng I / O pins trn MCU USB.
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TNG QUAN V CNG NGH ZIGBEE
33 | P a g e
Nh cp trong bng, sn lng phm iu khin c m ho nh l mt in p
tng t. iu ny c thc hin tit kim s lng chn yu cu trn MCU
giao din vi cc phm iu khin.
2. La chn ch chuyn i.
C bn gii php c th p dng in cho SmartRF05EB. Cc ngun nng lng c
th c la chn bng cch s dng la chn ngun nng lng nhy vo tiu
P11.
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TNG QUAN V CNG NGH ZIGBEE
34 | P a g e
Chuyn i ngun cung cp in chnh (P8) s tt tt c cc ngun nng lng, tr khi
mt ngun cung cp in bn ngoi c kt ni vi hi ng qun tr, trng cc iu
chnh in p trn tu.
3. Nng lng pin.
Hi ng qun tr nh gi bao gm mt pin cho hai pin AA 1.5V mt sau ca
PCB: pin AA bnh thng c th c s dng v ngun cung cp trn iu chnh
bng 3.25 V hi ng qun tr. Vic la chn o ngun in nn ngn mch pin 1
v 2 ca tiu P11. Mt LOW BATT LED trn bng s c thp sng khi in p
trn bng xung di 1,56 V. Lu rng chc nng ny ch hot ng khi to nng
lng cho hi ng qun tr s dng pin.
4. DC Jack.
SmartRF05EB c mt kt ni vi chun kt ni in DC jack vi mt pin 2.5mm
trung tm. Pin trung tm c s dng cho in p tch cc. Mt 4-10 V DC cung cp
in nn c s dng. Cc ngun cung cp iu chnh in p trn tu khong 3,05 V
hi ng qun tr. Vic la chn o ngun in nn ngn mch pin 2 v 3 ca tiu
P11.
5. in USB.
Khi SmartRF05EB c kt ni vi mt my tnh thng qua cp USB, n c th rt ra
nng lng t bus USB. Cc ngun cung cp iu chnh in p trn tu khong 3,05
V hi ng qun tr. Vic la chn o ngun in nn ngn mch pin 2 v 3 ca
tiu P11.
6. Cung cp in trong phng th nghim.
Khi kt ni mt ngun cung cp nng lng trong phng th nghim, mt t nn c
kt ni vi bt k ca cc tm lt GND trn din n. Loi b cc jumper la chn
ngun nng lng v p dng mt in p trong khong t 2.7V n 3.6V pin 2 vo
tiu P11. Chuyn i quyn lc chnh s khng c hiu lc trong trng hp ny.
Ch ! Lu rng iu ny s b qua tt c iu chnh in p trn bng c th c
nguy c gy thit hi cho cc thnh phn trn bng nu in p trn pin 2 vo tiu
P11 thp hn-0.3V hoc cao hn 3.9V (xp hng ti a cho CC2511) .
7. RS232 giao din UART.
Giao din UART c th c s dng bi cc ng dng ty chnh giao tip vi cc
thit b khc. Giao din s dng mt thit b dch in p cc cng tng thch vi
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TNG QUAN V CNG NGH ZIGBEE
35 | P a g e
tn hiu RS232. B chuyn i in p RS232 c th c v hiu ha bi shorting
pin 1 v 2 trn P10 vi mt jumper.
Hnh di y cho mt tng quan chi tit ca cc tn hiu UART v cch chng c
kt ni vi cc thit b khc nhau trn EB.
Nh hnh v, tn hiu c vt trn EB gia EM v CC2511 v gia EM v cc kt
ni mc RS232 converter/DE9. iu ny c ngha rng nu hi ng qun tr kt ni
vi giao din EM giao tip vi mt my tnh s dng UART, s dng mt cp ni tip
thng. giao tip vi CC2511 t mt my tnh, mt cp null-modem (vt qua)
c s dng. Giao tip UART gia CC2511 v b iu khin trn EM hot ng m
khng qua bt k tn hiu (RX kt ni vi TX v ngc li).
Cng lu rng nt USB v USB LED chia s RTS v CTS tn hiu i n CC2511.
trnh bt k xung t khi cc tn hiu iu khin lung RTS / CTS UART c s
dng, ngt kt ni nhy 1-2 v 3-4 trn P1. H ang b ngt kt ni theo mc nh.
8. Phm iu khin.
Phm iu khin pht hin nm v tr (trung tm, ln, xung, tri, phi) v mt s kin
(y). Trong trng hp di chuyn phm iu khin t v tr trung tm ca n hoc y
n, 5 tn hiu ri rc c th c s dng phn bit nhng g xy ra. Cc tn hiu
ri rc ch c sn cho cc vi iu khin trn EM. Ngoi ra, hai tn hiu tng hp c th
c s dng pht hin mt s kin iu khin. Mt tn hiu, JOY_MOVE, c
t cao trong trng hp bt k chuyn ng i t v tr trung tm, bao gm y. Cc
tn hiu khc, JOY_LEVEL, l mt tn hiu mc in p cung cp cho cc gi tr khc
nhau ty thuc vo v tr hin ti ca cc phm iu khin.
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TNG QUAN V CNG NGH ZIGBEE
36 | P a g e
9. Mn hnh LCD.
Mn hnh LCD trn SmartRF05EB l mt k t hin th 3x16 t Hitech Hin th
(HMC16311). S dng xe but SPI v tn hiu iu khin b sung (LCD CS, ch
mn hnh LCD v mn hnh LCD t li) kim sot mn hnh LCD.
10. Nt.
C nm nt trn bng nh gi.
Nt 1 v nt 2 ch kt ni vi EM, trong khi nt USB c kt ni vi b iu khin
USB. Khng c b lc RC trn cc nt.
Nt reset USB Thit lp li b iu khin USB. Lu rng b iu khin USB s ln
lt thit lp li EM, do nhn nt reset USB cng t li b iu khin trn EM.
Nt reset EM s ch dn n t li b iu khin trn EM (v d nh MSP430F2618
trn CCMSP EM).
11. n LED.
C 6 n LED trn din n.
Bn n LED D1, D2, D3 v D4 ch c th c iu khin thng qua EM.
LED D6 c th c iu khin bi b iu khin USB.
Cc LOW BATT LED c bt khi in p t pin gim xung di khong 1.56V. Ni tip Flash. SmartRF05EB c n flash thit b M25PE10 - 1 Mbit (128 Kb 8 bit) ni tip phn
trang b nh flash t STMicroelectronics. N c th c truy cp qua cc xe but SPI
t EM, nhng khng phi t b iu khin USB, v sau khng truy cp vo cc
tn hiu chn chip flash.
12. G li kt ni (P18 v P20).
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TNG QUAN V CNG NGH ZIGBEE
37 | P a g e
Cc kt ni debug a ra tt c cc tn hiu t cc kt ni EM. Cc kt ni tng thch
vi thit b thm d Agilent phn tch logic. Cc kt ni cho php d dng truy cp vo
I / O kt ni tn hiu v bng mu.
13. Kt ni EM.
Cc kt ni EM c s dng kt ni EM cho 05EB SmartRF. Cc kt ni P5 v
P6 c s dng nh giao din chnh.
14. Ph v ra tiu v nhy (P1 v P4).
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TNG QUAN V CNG NGH ZIGBEE
38 | P a g e
Cc tn hiu t cc kt ni EM c kt ni vi giao din ngi dng hoc CC2511
trn EB, nhng tt c cc tn hiu c gated thng qua mt trong hai phn u hoc
P1 P4. Jumper trn cc tiu cho php iu chnh tt kim sot cc tn hiu c
chuyn n thit b g v cho php d dng chia ra cc tn hiu g li v pht trin
bng cch s dng thit b ngoi vi c quyn.
Tt c cc thit b ngoi vi trn bng v b iu khin USB c th c c lp hon
ton t EM, to iu kin cho cc php o in nng tiu th chnh xc.
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TNG QUAN V CNG NGH ZIGBEE
39 | P a g e
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TNG QUAN V CNG NGH ZIGBEE
40 | P a g e
IV. CCMSP-EM430F2618.
Cc CCMSP-EM430F2618 l mt hi ng qun tr MCU chung chung m c th
c cm vo mt SmartRF05EB, cho php truy cp vo tt c cc giao din ngi
dng ca hi ng qun tr. Bt k TI LPW thu pht EM, hoc thm ch mt h thng
EM-on-chip, c th c cm vo hi ng qun tr MCU, cho php mt nn tng
pht trin linh hot kim tra RF v thit k phn mm.
1. JTAG giao din v ngun in.
Kt ni JTAG, nm pha bn phi ca hi ng qun tr, c s dng lp trnh
v g li phn mm chy trn MSP430F2618. Vui lng tham kho hng dn phn
mm CC2520DK ca ngi s dng bit thm chi tit v cch g ri c th c
s dng.
Tiu la chn ngun nng lng (P14) cho php la chn nhng g ngun in
s dng cho b iu khin MSP430. Nu nhy la chn v tr FET (ngn mch pin 2
v 3) hi ng qun tr c th c h tr t cc cng c FET. Lu rng nu hi
ng qun tr c cung cp t mt ngun th hai (v d nh SmartRF05EB), bn
s c hai ngun in ring bit. trnh thit hi ca hi ng qun tr, ch s dng
FET in nu hi ng qun tr cha c h tr.
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TNG QUAN V CNG NGH ZIGBEE
41 | P a g e
Nu cc jumper v tr LCL (ngn mch pin 1 v 2), hi ng qun tr c cung cp
t mt ngun khc nhau, v FET s dng m l u vo cho chnh xc chuyn i cp
in p ca cc tn hiu JTAG.
Cc thit lp mc nh l nhy LCL.
2. BSL hoc kt ni UART.
Tiu BSL / UART cho php h tr cho vic truy cp v s dng cc tnh nng Boot
Strap Loader ca MSP430.
V tr mc nh l UART, nh tuyn tn hiu UART (RX, TX, CTS v RTS) kt
ni RS232 UART trn EB.
Nu BSL c chn, cc tn hiu cn thit (BSL RX, TX BSL, RST v TST) c th
c truy cp t CC2511. Phn mm ty chnh c th c thc hin s dng cc
tnh nng. N cng c th kt ni mt cp bn ngoi truy cp vo BSL.
Vui lng tham kho cc bo co ng dng www.ti.com/lit/slaa089 v
www.ti.com/lit/slaa096 bit thm chi tit.
3. ch SPI.
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TNG QUAN V CNG NGH ZIGBEE
42 | P a g e
Hi ng qun tr CCMSP-EM430F2618 h tr hai ch SPI ln v mt ch th
ba cho php mt "b qua" ch c bit. Ch SPI c chn vi jumper trn tiu
P9.
3.1. SPI Ch 1 (SPI_M1).
y l ch mc nh SPI v s dng hai bus SPI ring bit. Mt l dnh ring
giao tip vi cc m-un EM v cc khc l dnh ring cho tt c cc thit b SPI trn
EB. MSP430 s dng USCIB1 giao din ni tip ni b cho cc EM v USCIB0 cho
EB. Con s di y bit chi tit se.
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TNG QUAN V CNG NGH ZIGBEE
43 | P a g e
Ch ny cho php s dng lin tc ca xe but thng tin lin lc vi EM trong khi
s dng thit b ngoi vi trn EB (thng cp nht cc mn hnh LCD hoc truy cp
vo n flash ni tip) ti cc chi ph cn hai cng ni tip trn vi iu khin.
3.2. SPI Ch 2 (SPI_M2).
Mt ch thay th l s dng ch c mt SPI xe but cho tt c cc thit b. iu ny
t c bng cch s dng SPI ch 2.
Trong trng hp ny, USCIB0 c s dng truy cp vo c hai thit b SPI trn
EB v EM. Trong mt s trng hp, iu ny c th lm phc tp cc phn mm, v
n cn m bo giao dch SPI lin tc khng b gin on sm (v d nh gin on
t i pht thanh gy nn c t thu pht bng cch s dng xe but SPI trong khi
MCU l gia vn bn cho mn hnh LCD).
3.3. SPI ch 3 (ch Bypass).
SPI ch 3 l mt ch c bit cho php b iu khin USB trn EB truy cp
vo EM, v do b qua MSP430. Lu rng mt trong hai SPI_M1 hoc SPI_M2
phi c la chn cng mt lc cho cc ch b qua lm vic.
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TNG QUAN V CNG NGH ZIGBEE
44 | P a g e
Cng lu rng trong ch ny , c hai MSP430 v CC2511 ang hot ng nh
SPI thc s. MSP430 c thit lp ch a ch (cho php 4 dy SPI giao din )
cc ch hot ng ng .
Ch b qua ch c hiu lc khi CC2511 khng nh tn hiu chn chip. Vo lc ny,
MSP430 s pht hin rng cc tn hiu CS i thp, do gii phng cc xe but , hot
ng nh mt n l th ng. Tn hiu chn chip ny c chuyn n cc tn hiu
chn con chip EM , cho php giao din SPI ca n . By gi CC2511 c th hot ng
nh SPI ch v giao tip vi EM nh MSP430 khng c mt trn xe but . Chip
EM chn tn hiu t MSP tm thi s b ngt kt ni .
Mt khi CC2511 de- khng nh tn hiu chn chip, hi ng qun tr MCU quay tr
li vi mt trong nhng
chn ch SPI ( SPI_M1 hoc SPI_M2 ) .
Ch ny c th c bit hu ch cho cc mc ch g li. Trong khi g li phn
mm trn MSP430 v s dng RF EM , c th ngn chn cc ng dng MSP430 (v
d nh mt breakpoint ) v s dng SmartRF Studio c s ng k t cc i
pht thanh - m khng can thip vi cc ng dng .
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