Mch Kha SGVHD:V MINH THNG

NHN XT CA GIO VIN HNG DN. 000

Nng, ngy ...thng....nm 2014 Ch k ca GVHD

NHN XT CA GIO VIN PHN BIN. 000

Nng, ngy ...thng.... nm 2014 Ch k ca GVPB

LI CAM OAN

Ti xin cam oan nhng ni dung trong lun vn ny l do ti thc hin di s hngdn trc tip ca thy ThS. V Minh Thng. Mi tham kho dng trong n u c trch dn r rng tn tcgi, thi gian, a im cng b. Mi sao chp khng hp l, vi phm quy ch o to, hay gian tr, ti xin chu hon ton trch nhim.

Nhm Sinh Vin Thc Hin

LI NI U

K thut vi iu khin c pht trin v ng dng rng ri trn th gii trong rt nhiu lnh vc khc nhau, khc phc c nhng vn v c kh. ng dng k thut vi iu khin l s pht trin cn thit ca mt x hi hin i.Trong qu trnh hc tp chng em c c hi lm quen vi vi iu khin qua cc mn hc trn lp v tm hiu thm thng qua cc ti liu sch bo v internet, chng em nhn thy: ng dng vi iu khin vo cuc sng l mt iu th v v l c mt qu trnh sng toTrong n k thut vi iu khin v kt ni ngoi vi ny,chng em chn ti: Mch kha s Tuy chng em c gng thc hin n tt nht c th, nhng vn khng trnh c thiu st, mong qu Thy C gp v thng cm cho nhng thiu st ca chng em.

LI CM N

Sau mt thi gian nghin cu, tm ti, tnh ton di s ch dn tn tnh ca thy V Minh Thng cng cc thy c trong khoa in t - Vin thng em hon thnh ti n cdio : Thit k mch kha s.Trong qu trnh hon thnh n, chng ti hc hi c rt nhiu iu b ch:Chng ti ch ng hn trong hc tp, lm quen vi phng php hc tp, trao i trc tip vi ging vin v qua Mail.Gipchng ti c kh nng tm ti, sng to, t lp phng php tm kim ti liu t cc ngun khc nhauQua vic thc hin n ny, chng ti c thm nhiu kinh nghim trong vic lm mch v trong phng php trnh by tng ca mnh.Tuy nhin trong qu trnh thc hin cn gp rt nhiu kh khn, v vy n hon thnh vn cn nhiu thiu xt, khng c nh mong i. Mong qu thy c tip tc gip hn na chng ti c th hon thin hn k nng ca mnh v p dng vo cc ti sau ny.Mt ln na chng ti xin chn thnh cm n thy V Minh Thng tn tnh ch bo, gip chng ti c th hon thnh tt ti n cdio ln ny. Chng ti xin chn tnh cm n.

Chng 1TNG QUAN H THNG MCH KHO S

y l mt h thng ng m theo m s, cho php mt s t ngi c th ng m theo m s ca h. N c th c p dng lm kho ca ra vo cho cc h thng cn mang tnh bo mt, gii hn s ngi ra vo nh: ca ra vo c quan, nh ring, nh my, cc khu quan trng...Trn c s , h thng phi m bo c hai yu cu c bn sau: Tnh an ton: phi c chc nng bo mt. D s dng: c y hng dn ngi dng s dng.Do nhng nhm thc hin ti a ra yu cu mt h thng ng m c cc chc nng nh sau:1.1 Chc nng h thng:H thng qun l cc m s ng vi mt s ngi c cho php ra vo ca ny v hot ng trn c s cc m ny. M s dng cc ch s t 0 n 9. di ca m t 1 n10 ch s, mc nh l 8 k t. H thng giao tip vi ngi dng thng qua mt bn phm iu khin v hin th trn mn hnh LCD. Bn phm gm cc phm: Phm s: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 Phm Unlock: Dng m kha h thng Phm Lock: Dng kha h thng Phm Change: Dng thay i mt khu h thng Phm OK: Dng kt thc sau khi nhp m Phm Cancel: Dng hy khi nhp m hay thay i mt m Phm Clear: Dng xa v nhp li

1.2 Phn tch h thng:1.2.1 Kh nng p ng yu cu ca h thngH thng giao tip vi ngi s dng ch bng bn phm v hin th ra mn hnh LCD, do vy n hn ch c tc ng ca ngi s dng vo ni dung bn trong ca kho.Thm vo l kh nng bo ng khi nhp sai m s qu s ln cho php lin tip lm cho h thng c tnh an ton cao.Nu nghi ng b l mt m, ngi s dng c th thay i m s theo mong mun. Nh m kh nng bo mt ca h thng cng c tng ln.1.2.2 Phn tch h thngDo gii hn v thi gian v yu cu t ra nn nhm thc hin ti ch tp trung vo phn thit k mch in t iu khin h thng nyH thng gm 3 khi c bn: Khi bn phm: gm 16 phm s dng, gm: 10 phm nhp s t 0-9, 6 phm chc nng: Lock, Unlock, Chage, Cancel, Clear Khi x l: Lm cc nhim v t ra nh trong phn chc nng ca h thng. Khi hin th: Gip cho vic giao tip vi ngi s dng tr nn d dng hn, lm cho sn phm mang tnh thn thin, d tng tc, gip ngi s dng bit c mnh ang thc hin thao tc g vi kho.1.2.3 S khi tng qut

Hnh 1.1: S khi ca h thng

1.3 La chn phn cngTrn c s cc yu cu t ra cho ti v qua cc phn tch s b, Nhm chn phn cng nh sau1.3.1 Khi bn phmBn phm gm 16 nt nhn ln. Mi nt l mt b phn ng m bng c kh. 16 Nt nhn c mc thnh ma trn phm 4x4. S dng phng php qut hng v ct nhn bit cc phm bm. Yu cu 8 ng tn hiu a vo VK1.3.2 Khi vi x lDng vi iu khinu im: Vi iu khin c kh nng iu khin linh hot theo mong mun ca ngi s dng da vo phn mm c vit. Kh nng thay i m c th thc hin c. H thng n gin hn nhiu, kch thc nh. Hn na s gim c km n nh do nhiu linh kin gy ra. C th thay i, thm chc nng bng cch thay i phn mm.Nhc im: Cht lng ca h thng ph thuc vo cht lng chng trnh c np cho vi iu khin.T yu cu ca bi ta d kin dng cc chip vi iu khin thuc h MCS-51 ca Intel, m c th y l dng chip 8051 v nhng l do sau: Th nht 8051 thuc h MCS-51, l chip vi iu khin. c im ca cc chip vi iu khin ni chung l n c tch hp vi y chc nng ca mt h VXL nh, rt thch hp vi nhng thit k hng iu khin. Tc l trong n bao gm: mch vi x l, b nh chng trnh v d liu, b m, b to xung, cc cng vo/ra ni tip v song song, mch iu khin ngt Th hai l, vi iu khin 8051 cng vi cc h vi iu khin khc ni chung trong nhng nm gn y c pht trin theo cc hng sau:

Gim nh dng tiu th. Tng tc lm vic hay tn s xung nhp ca CPU. Gim in p ngun nui. C th m rng nhiu chc nng trn chip, m rng cho cc thit k ln.Nhng c im dn n t c hai tnh nng quan trng l: gim cng sut tiu th v cho php iu khin thi gian thc nn v mt ng dng n rt thch hp vi cc thit k hng iu khin. Th ba l, vi iu khin thuc h MCS-51 c h tr mt tp lnh phong ph nn cho php nhiu kh nng mm do trong vn vit chng trnh phn mm iu khin. Cui cng l, cc chip thuc h MCS-51 hin c s dng ph bin v c coi l chun cng nghip cho cc thit k kh dng. Vi sinh vin mi lm quen vi VK th 8051 c nhiu ti liu tham kho, ng thi cng s dng n gin nht. Mt khc, qua vic kho st th trng linh kin vic c c chip 8051 l d dng nn m ra kh nng thit k thc t.1.3.3 Khi hin thYu cu t ra i vi khi hin th l thn thin vi ngi s dng gip ngi dng d dng thao tc vi kho. Nhm quyt nh s dng LCD 16x2

u im: Hin th r rng c km theo ch dn. Thay i ni dung linh hot. X l lp trnh n gin hn Led 7 on v Led ma trn.Nhc im: Gi thnh t.1.3.4 Kt lunSau khi cn nhc cc phng n a ra, v kh nng phi hp gia cc khi, nhm thc hin ti a ra phng n la chn phn cng nh sau: S dng bn phm ma trn 4x4. Khi hin th dng LCD 16x2. Khi vi x l dng vi iu khin AT89C51.Chng 2KHO ST KHI VI X L

Nhim v ca khi vi x l trung tm c m phm t bn phm kim tra xem phm no c n v thc hin chc nng ca phm . Lu gi tr ca cc m s m kha. Lu cc chng trnh x l phm n: m kha, i m, bo ng Lu chng trnh iu khin LCD.2.1 S lc vi iu khin h MSC-51Vi iu khin 8051 l mt trong nhng vi iu khin 8 bit thng dng nht hin nay. Bt u xut hin vo nm 1980, tri qua gn 30 nm, hin c ti hng trm bin th c sn xut bi hn 20 hng khc nhau, trong phi k n cc i gia trong lng bn dn nh ATMEL, Texas Instrument, Philips, Analog Devices Ti Vit Nam, cc bin th ca hng ATMEL l AT89C51, AT89C52, AT89S51, AT89S52 c thi gian xut hin trn th trng kh lu v c th ni l c s dng rng ri nht trong cc loi vi iu khin 8 bit. Chng ny s tp trung m t tng i chi tit cu trc bn trong ca vi x l AT89C52 ca hng ATMEL.Cc vi iu khin h MCS-51 c cc c im chung nh sau: C 4 Kb b nh FLASH ROM bn trong dng lu chng trnh iu khin. C 128 Byte RAM ni. 4 Port xut/nhp (Input/Output) 8 bit. C kh nng giao tip truyn d liu ni tip. C th giao tip vi 64Kb b nh bn ngoi lu chng trnh iu khin. C th giao tip vi 64 Kb b nh bn ngoi dng lu d liu. C 210 bit c th truy xut tng bit. C cc lnh x l bit.Tt c cc vi iu khin cng h MCS-51 hoc MCS-52 u c cc c tnh c bn ging nhau nh phn mm, cn phn cng th khc nhau, cc vi iu khin sau ny s c nhiu tnh nng hay hn cc vi iu khin th h trc. V d vi iu khin 89C51 s tin cho vic s dng hn vi iu khin 80C51 hay 87C51. Vi iu khin 89S51 s hay hn 89C51 v c nhiu thanh ghi hn, c thm ch np ni tip rt tin li. Nhng th h i sau s k tha tt c nhng g ca th h i trc. Trong phn ny ch cp n vi iu khin 89C51.2.2 Kho st s chn 89C512.2.1 S chnVi iu khin 89C51 c tt c 40 chn. Trong c 24 chn c tc dng kp (c ngha l 1 chn c 2 chc nng), mi ng c th hot ng nh ng xut nhp iu khin IO (Input/Output) hoc l thnh phn ca cc bus d liu v bus a ch ti a ch v d liu khi giao tipvi b nh ngoi.

Hnh 2.1: S chn ca 89C512.2.2 Chc nng cc chnCc Port Port 0:Port 0 l port c 2 chc nng vi s th t chn 3239.Trong cc h thng iu khin n gin s dng b nh bn trong khng dng b nh m rng bn ngoi th Port 0 c dng lm cc ng iu khin IO (Input - Output).Trong cc h thng iu khin ln s dng b nh m rng bn ngoi th Port 0 c chc nng l bus a ch v bus d liu AD7 AD0 (Address: a ch, Data: d liu). Port 1:Port 1 vi s th t chn 18. Port 1 ch c 1 chc nng dng lm cc ng iu khin xut nhp IO, Port 1 khng c chc nng khc. Port 2:Port 2 l Port c 2 chc nng vi s th t chn 2128.Trong cc h thng iu khin n gin s dng b nh bn trong khng dng b nh m rng bn ngoi th Port 2 c dng lm cc ng iu khin IO.Trong cc h thng iu khin ln s dng b nh m rng bn ngoi th Port 2 c chc nng l bus a ch cao A8A15. Port 3:Port 3 l port c 2 chc nng vi s th t chn 1017.Cc chn ca Port ny c nhiu chc nng, cc cng dng chuyn i c lin h vi cc c tnh c bit ca 89C51 nh bng: Bng 2.1: Chc nng cc chn ca Port 3BitTnChc nng chuyn i

P3.0RxDNg vo nhn d liu ni tip.

P3.1TxDNg vo xut d liu ni tip.

P3.2

Ng vo ngt cng th 0.

P3.3

Ng vo ngt cng th 1.

P3.4T0Ng vo ca timer/counter th 0.

P3.5T1Ng vo ca timer/counter th 1.

P3.6

Tn hiu iu khin ghi d liu ln b nh ngoi.

P3.7

Tn hiu iu khin c d liu t b nh ngoi.

Cc tn hiu iu khin Tn hiu (Program Store Enable):

l tn hiu ng ra chn 29 c tc dng cho php c b nh chng trnh m rng hng ni n chn (Output Enable hoc ) ca EPROM cho php c cc byte m lnh.

Khi c giao tip vi b nh chng trnh bn ngoi th mi dng n , nu khng c giao tip th chn b trng.

mc thp trong thi gian vi iu khin 89C51 ly lnh. Cc m lnh ca chng trnh c t EPROM qua bus d liu v c cht vo thanh ghi lnh bn trong 89C51 gii m lnh. Khi 89C51 thi hnh chng trnh trong EPROM ni th mc logic 1. Tn hiu iu khin ALE (Address Latch Enable) :Khi vi iu khin 89C51 truy xut b nh bn ngoi, Port 0 c chc nng l bus ti a ch v bus d liu [AD7 AD0] do phi tch cc ng d liu v a ch. Tn hiu ra ALE chn th 30 dng lm tn hiu iu khin gii a hp cc ng a ch v d liu khi kt ni chng vi IC cht.Tn hiu ra chn ALE l mt xung trong khong thi gian Port 0 ng vai tr l a ch thp nn vic cht a ch c thc hin 1 cch hon ton t ng.Cc xung tn hiu ALE c tn s bng 1/6 tn s dao ng thch anh gn vo vi iu khin v c th dng tn hiu xung ng ra ALE lm xung clock cung cp cho cc phn khc ca h thng.Trong ch lp trnh cho b nh ni ca vi iu khin th chn ALE c dng lm ng vo nhn xung lp trnh t bn ngoi lp trnh cho b nh Flash Rom trong 89C51. Tn hiu (External Access):

Tn hiu vo chn 31 thng ni ln mc 1 hoc mc 0.

Nu ni ln mc logic 1 (+5v) th vi iu khin s thi hnh chng trnh t b nh ni.

Nu ni vi mc logic 0 (0V) th vi iu khin s thi hnh chng trnh t b nh ngoi. Tn hiu RST (Reset):Ng vo RST chn 9 l ng vo Reset ca 89C51. S kt ni mch reset nh sau:

Hnh 2.2: S kt ni mch Reset cho vi iu khin 8051Khi cp in cho h thng (hnh b t reset khi cp in) hoc khi nhn nt reset (hnh a) th mch s reset vi iu khin. Khi reset th tn hiu reset phi mc cao t nht l 2 chu k my, khi cc thanh ghi bn trong c np nhng gi tr thch hp khi ng h thng.Thanh ghi quan trng nht l thanh ghi b m chng trnh PC = 0000H. Sau khi reset, vi iu khin lun bt u thc hin chng trnh ti a ch 0000H ca b nh chng trnh nn cc chng trnh vit cho vi iu khin lun bt u vit ti a ch 0000H.Ni dung ca RAM trong vi iu khin khng b thay i bi tc ng ca ng vo reset (c ngha l vi iu khin ang s dng cc thanh ghi lu tr d liu nhng nu vi iu khin b reset th d liu trong cc thanh ghi vn khng i).Trng thi ca tt c cc thanh ghi sau khi reset h thng c tm tt nh bng:Bng 2.2: Trng thi cc thanh ghi sau khi reset vi iu khinThanh ghiNi dung

B m chng trnh PC0000H

Thanh ghi tch lu A00H

Thanh ghi B00H

Thanh ghi trng thi PSW00H

Thanh ghi con tr SP07H

DPTR0000H

Port 0 n Port 3FFH (1111 1111)

IPXXX0 0000B

IE0X0X 0000B

Cc thanh ghi nh thi00H

SCON SBUF00H

PCON (HMOS)00H

PCON (CMOS)0XXX XXXXH0XXX 0000B

Cc ng vo b dao ng XTAL1, XTAL2:B dao ng c tch hp bn trong 89C51, khi s dng 89C51 ngi thit k ch cn kt ni thm t thch anh v cc t nh trong hnh di.Tn s t thch anh thng s dng cho 89C51 l 12Mhz 24Mhz.

Hnh 2.3: S kt ni mch dao ng dng thch anh cho vi iu khin 8051T C1 v C2 dng trong mch ny l cc t in khng phn cc c gi tr 30pF10pF. Chn 40 (VCC) c ni ln ngun 5V, chn 20 (GND) ni mass.2.3 T chc b nhVi iu khin 89C51 c b nh ni bn trong v c thm kh nng giao tip vi b nh bn ngoi nu b nh bn trong khng kh nng lu tr chng trnh.B nh ni bn trong gm c 2 loi b nh: b nh d liu v b chng trnh. B nh d liu c 256 byte, b nh chng trnh c dung lng 4Kb (89C52 c 8Kb).B nh m rng bn ngoi cng c chia ra lm 2 loi b nh: b nh d liu v b nh chng trnh. Kh nng giao tip l 64Kb cho mi loi.B nh m rng bn ngoi v b nh chng trnh bn trong khng c g c bit, ch c chc nng lu tr d liu v m chng trnh nn khng cn phi kho st.B nh chng trnh bn trong ca vi iu khin thuc loi b nh Flash Rom cho php xa bng xung in v lp trnh li.B nh ram ni bn trong l mt b nh c bit ngi s dng vi iu khin cn phi nm r cc t chc v cc chc nng c bit ca b nh ny.

Hnh 2.4: Cc vng nh ca 89C51RAM bn trong 89C51 c phn chia nh sau: Cc bank thanh ghi c a ch t 00H n 1FH. RAM truy xut tng bit c a ch t 20H n 2FH. RAM a dng t 30H n 7FH. Cc thanh ghi chc nng c bit t 80H n FFH. Cc bank thanh ghi :32 byte thp ca b nh ni c dnh cho 4 bank thanh ghi.B lnh 89C51 h tr thm 8 thanh ghi c tn l R0 n R7 v theo mc nh sau khi reset h thng th cc thanh ghi R0 n R7 c gn cho 8 nh c a ch t 00H n 07H, khi bank 0 c 2 cch truy xut bng a ch trc tip v bng thanh ghi R.

Hnh 2.5: Cu trc b nh RAM bn trong vi iu khin.

Cc lnh dng cc thanh ghi R0 n R7 s c s lng byte m lnh t hn v thi gian thc hin lnh nhanh hn so vi cc lnh c chc nng tng ng nu dng kiu a ch trc tip.Cc d liu dng thng xuyn nn lu tr mt trong cc thanh ghi ny.Do c 4 bank thanh ghi nn ti mt thi im ch c mt bank thanh ghi c truy xut bi cc thanh ghi R0 n R7, chuyn i vic truy xut cc bank thanh ghi ta phi thay i cc bit chn bank trong thanh ghi trng thi.Ngi lp trnh dng vng nh 4 bank thanh ghi lu tr d liu phc v cho vic x l d liu khi vit chng trnh.Chc nng chnh ca 4 bank thanh ghi ny l nu trong h thng c s dng nhiu chng trnh th chng trnh th nht bn c th s dng ht cc thanh ghi R0 n R7 ca bank0, khi chuyn sang chng trnh th 2 x l mt cng vic g v vn s dng cc thanh ghi R0 n R7 lu tr cho vic x l d liu m khng lm nh hng n cc d liu R0 n R7 trc y v khng cn phi thc hin cng vic ct d liu th cch nhanh nht l gn nhm thanh ghi R0 n R7 cho bank 1 l xong. Tng t c th m thm hai chng trnh na v gn cho cc bank 3 v 4. RAM c th truy xut tng bit:Vi iu khin 89C51 c 210 nh bit c th truy xut tng bit, trong c 128 bit nm cc nh byte c a ch t 20H n 2FH v cc bit cn li cha trong nhm thanh ghi c chc nng c bit.Cc nh cho php truy xut tng bit v cc lnh x l bit l mt th mnh ca vi iu khin. Cc bit c th c t, xa, AND, OR bng 1 lnh duy nht, trong khi x l cc bit th vi x l vn c th x l c nhng phi s dng rt nhiu lnh t c cng mt kt qu v vi x l thng x l byte.Cc Port cng c th truy xut c tng bit.128 nh bit cho php truy xut tng bit v cng c th truy xut byte ph thuc vo lnh c dng l lnh x l bit hay lnh x l byte. Ch a ch ca nh byte v bit trng nhau.Ngi lp trnh dng vng nh ny lu tr d liu phc v cho vic x l d liu byte hoc bit. Cc d liu x l bit nn lu vo vng nh ny.Ch : cc nh no m chia ra lm 8 v c cc con s bn trong l cc nh va cho truy xut byte v c truy xut bit. Nhng nh cn li th khng th truy xut bit. Cc s nm bn trong tng bit l a ch ca tng bit. RAM a dng :Vng nh ram a dng gm c 80 byte c a ch t 30H n 7FH vng nh ny khng c g c bit so vi 2 vng nh trn. Vng nh bank thanh ghi 32 byte t 00H n 1FH cng c th dng lm vng nh ram a dng mc d cc nh ny c chc nng nh trnh by.Mi a ch trong vng RAM a dng u c th truy xut t do dng kiu nh a ch trc tip hoc gin tip.B nh ngn xp ca vi iu khin dng Ram ni nn dung lng b nh ngn xp nh, trong khi cc vi x l dng b nh bn ngoi lm b nh ngn xp nn dung lng ty m rng.2.4 Cc thanh ghi c chc nng c bitVi iu khin 89C51 c 21 thanh ghi c chc nng c bit nm vng trn ca RAM ni c a ch t 80H n FFH: Cc nh c a ch 80H, 90H, A0H, B0H:L cc Port ca 89C51 bao gm Port 0 c a ch 80H, Port 1 c a ch 90H, Port 2 c a ch A0H v Port 3 c a ch B0H. Tt c cc Port ny u c th truy xut tng bit nn rt thun tin trong iu khin. a ch ca cc bit c t tn vi bt u chnh l a ch ca Port tng ng v d nh bit u tin ca Port 0 l 80h cng chnh l a ch bt u ca Port 0. Ngi lp trnh khng cn nh a ch cc bit trong cc Port v phn mm lp trnh cho php truy xut bng tn tng bit d nh nh sau: P0.0 chnh l bit c a ch 80h ca Port 0.Ngoi tr thanh ghi A c th c truy xut ngm, a s cc thanh ghi c chc nng c bit SFR c th a ch ha tng bit hoc byte. nh c a ch 81H:L thanh ghi con tr ngn xp SP (Stack Pointer) c chc nng qun l a ch ca b nh ngn xp. B nh ngn xp dng lu tr tm thi cc d liu trong qu trnh thc hin chng trnh ca vi iu khin.Cc lnh lin quan n ngn xp bao gm cc lnh ct d liu vo ngn xp (lnh Push) v ly d liu ra khi ngn xp (lnh Pop).Lnh ct d liu vo ngn xp s lm tng SP trc khi ghi d liu vo.Sau lnh ly d liu ra khi ngn xp s lm gim SP.Khi Reset 89C51 th thanh ghi SP s mang gi tr mc nh l 07H v d liu u tin s c ct vo nh ngn xp c a ch 08H. nh c a ch 82H v 83H:L 2 thanh ghi DPL (byte thp) c a ch l 82H v DPH (byte cao) c a ch 83H. Hai thanh ghi ny c th s dng c lp lu tr d liu v c th kt hp li to thnh 1 thanh ghi 16 bit c tn l DPTR v gi l con tr d liu - c dng lu a ch 16 bit khi truy xut d liu ca b nh d liu bn ngoi. Cc vi iu khin sau ny c thm thanh ghi DPTR 1. nh c a ch 87H:L thanh ghi PCON (Power Control) c chc nng iu khin cng xut khi vi iu khin lm vic hay ch ch. Khi vi iu khin khng cn s l g na th ngi lp trnh c th lp trnh cho vi iu khin chuyn sang ch ch gim bt cng sut tiu th nht l khi ngun cung cp cho vi iu khin l pin. Cc nh c a ch t 88H n 8DH:L cc thanh ghi phc v cho 2 timer/counter T1, T0.Thanh ghi TCON (Timer Control): thanh ghi iu khin timer/counter.Thanh ghi TMOD (Timer Mode): thanh ghi la chn mode hot ng cho timer/counter.Thanh ghi TH0 v TL0 kt hp li to thnh 1 thanh ghi 16 bit c chc nng lu tr xung m cho timer/counter T0. Tng t cho 2 thanh ghi TH1 v TL1 kt hp li lu tr xung m cho timer/counter T1. Kh nng lu tr s lng xung m c l 65536 xung. Cc nh c a ch 98H v 99H:L 2 thanh ghi SCON v SBUF. SCON (Series Control): thanh ghi iu khin truyn d liu ni tip. SBUF (Series Buffer ): thanh ghi m d liu truyn ni tip. D liu mun truyn i th phi lu vo thanh ghi SBUF v d liu nhn v ni tip cng lu thanh ghi ny. Khi c s dng truyn d liu th phi s dng 2 thanh ghi ny. Cc nh c a ch A8H v B8H:L 2 thanh ghi IE v IP. Thanh ghi IE (Interrupt Enable): thanh ghi iu khin cho php/khng cho php ngt. Thanh ghi IP (Interrupt Priority): thanh ghi iu khin u tin ngt. Khi c s dng n ngt th phi dng n 2 thanh ghi ny. Mc nhin cc thanh ghi ny c khi to ch cm ngt. Thanh ghi trng thi chng trnh (PSW: Program Status Word):Chc nng tng bit trng thi: C Carry C (Carry Flag):C nh c tc dng kp. C C c s dng cho cc lnh ton hc:C = 1 nu php ton cng c trn hoc php tr c mn.C = 0 nu php ton cng khng trn v php tr khng c mn. C Carry ph AC (Auxiliary Carry Flag):Khi cng nhng gi tr BCD (Binary Code Decimal), c nh ph AC c set [AC=1] nu kt qu 4 bit ln hn 09H, ngc li AC= 0. C AC c dng chnh s BCD khi thc hin lnh cng 2 s BCD. C 0 (Flag 0):C 0 (F0) cn gi l c Z, c Z =1 khi kt qu x l bng 0 v c Z = 0 khi kt qu khc 0. Cc bit chn bank thanh ghi truy xut:Hai bit RS1 v RS0 dng thay i cch gn 8 thanh ghi R7 R0 cho 1 trong 4 bank thanh ghi. Hai bit ny s b xa sau khi reset vi iu khin v c thay i bi chng trnh ca ngi lp trnh. Bng 2.3: Cc bit la chn bank thanh ghi.RS1RS0Bank thanh ghi c chn

00Bank 0

01Bank 1

10Bank 2

11Bank 3

C trn OV (Over Flag):Khi cc s c du c cng hoc tr vi nhau, phn mm c th kim tra bit ny xc nh xem kt qu c nm trong vng gi tr xc nh hay khng. Vi s nh phn 8 bit c du th s dng t 0 n +127, s m t -128 n -1. Nu kt qu cng 2 s dng ln hn +127 hoc cng 2 s m kt qu nh hn -128 th kt qu vt ra ngoi vng gi tr cho php th khi ALU trong vi iu khin s lm bit OV = 1.Khi cng cc s nh phn khng du th khng cn quan tm n bit OV. Bit Parity (P):Bit P t ng c Set hay Clear mi chu k my lp Parity chn vi thanh ghi A. m cc bit 1 trong thanh ghi A cng vi bit Parity lun lun l s chn. V d thanh ghi A cha nh phn 10101101B th bit P set ln mt cho bit tng s bit 1 trong thanh ghi A v c bit P to thnh s chn.Bit Parity thng c dng kt hp vi nhng th tc truyn d liu ni tip to ra bit Parity cho d liu trc khi truyn i hoc kim tra bit Parity sau khi nhn d liu. Thanh ghi B :Thanh ghi B a ch F0H c dng cng vi thanh ghi A thc hin cc php ton nhn chia.Thanh ghi B c th c dng nh mt thanh ghi m trung gian nhiu chc nng.2.5 Chi tit v khi Vi iu khin trong mch

Hnh 2.6 Mch nguyn l khi Vi x l

Hnh 2.7 Khi Vi iu khin Port 3 ni vi 4 ng d liu ca LCD Port 2 Ni vi ma trn phm 4x4 m bo mc logic dng in tr thanh 1K2 ni vi Port0, Port1 v Port2 Dng thch anh 12Mhz cp xung Clock Cc chn P3.5 v P3.7 dng iu khin LCD Chn P1.0,P1.1,P1.2,P1.3 v p1.4 iu khin n bo ng. Mch RESET khi cp ngun hoc nhn nt RESET Ngun nui 5V DC

Chng 3KHO ST KHI HIN TH

Khi ny s dng mt LCD 16x2 hin th cc thng tin khi s dng kha v c iu khin bi khi vi x l trung tm.3.1 Gii thiu chungVi cc u im nh: tiu th dng thp, hin th c hnh nh/k t linh hot tt hn nhiu so vi LED, mn hnh tinh th lng LCD (Liquid Crystal Display) c s dng trong hu ht cc thit b iu khin trong cng nghip hin th trng thi ca my mc. Ngy nay, vi cng ngh pht trin gi thnh ca LCD cng gim nhiu.Do c rt nhiu chng loi khc nhau nn LCD c s dng rt rng ri. Tt c cc LCD u c sn xut theo cc chun chung, tch hp lun cc module iu khin (cho LCD) nn vic s dng n khng my phc tp. B iu khin LCD cung cp mt tp lnh dng diu khin LCD.Trong ng dng c th ny, do khng yu cu hin th phc tp nn em chn loi LCD kiu k t, vi 16 k t, 2 hng (16characters x 2lines). Tn ca LCD ny l DM1602A.

Hnh 3.1: Hnh dng LCD DM1602A trong thc t

3.2 S chn v chc nng3.2.1 S chn

Hnh 3.2: S chn LCD DM1602A3.2.2 Chc nngBng 3.1: Chc nng chi tit cc chn ca LCD DM1602ASchnTnChc nngMc logicI/OM t

1VssNgun cp cho LCD--GND

2VddNgun cp cho LCD--+5V

3VeeChnh tng phn--0 n +5V

4RSiu khin hot ng ca LCD0ID0 - D7 ng vai tr l ng vo lnh

1ID0 - D7 ng vai tr l ng vo d liu

5R/W0IGhi thng tin (t b iu khin n LCD)

1Ic thng tin (t LCD n b iu khin)

6E0ICm truy xut LCD

1ILCD hot ng bnh thng

T 1xung0ICc d liu/ Lnh c truyn ti LCD

7D0D liu / Lnh0/1I/OBit 0 (LSB)

8D10/1I/OBit 1

9D20/1I/OBit 2

10D30/1I/OBit 3

11D40/1I/OBit 4

12D50/1I/OBit 5

13D60/1I/OBit 6

14D70/1I/OBit 7 (MSB)

15ANgun cung cp cho LED nn--V (+)

16KNgun cung cp cho LED nn--0 V

3.3 Cc thanh ghi v b nh ca LCD3.3.1 Cc thanh ghiThanh ghi IR: Mi lnh ca LCD c nh sn xut nh a ch r rng. Ngi dng ch vic cung cp a ch lnh bng cch np vo thanh ghi IR.V d: Lnh hin th mn hnh v con tr c m lnh l 00001110Thanh ghi DR: Dng cha d liu 8 bit ghi vo vng nh DDRAM hoc CGRAM ( ch ghi), hoc dng cha d liu t hai vng ram ny gi ra cho MCU ( ch c).C bo bn BF (Busy Flag): Khi ang thc thi cc hot ng bn trong, LCD b qua mi giao tip vi bn ngoi v bt c BF (thng qua chn DB7 khi c thit lp RS=0, R/W=1) ln cho bit n ang bn.B m a ch AC (Address Counter): Khi mt a ch lnh c np vo thanh ghi IR, thng tin c ni trc tip cho hai vng RAM (vic chn la vng RAM tng tc bao hm bn trong m lnh). Sau khi ghi vo (hoc c ra) t RAM, b m AC t ng tng ln (hoc gim xung) mt n v.3.3.2 B nhVng RAM hin th DDRAM (Display Data Ram)

Hnh 3.3: DDRAM ca LCDVng CGROM (Character Generator Rom): Cha cc mu k t loi 5x7 hoc 5x10 im nh/ k t v nh a ch bng 8 bitBng 3.2: Cc mu k t ca LCD

Tnh theo cc ct l 4 bit cao, tnh theo cc hng l 4 bit thp trong 8 bit d liu. Cch tra bng l ging theo hng v theo ct c m hex ca tng k t.Vng CGRAM (Character Generator Ram)3.4 iu khin hot ng ca LCDHot ng ca LCD c iu khin thng qua 3 tn hiu E, RS, RW: Tn hiu E l tn hiu cho php gi d liu. gi d liu n LCD, chng trnh phi thit lp E=1, sau t cc trng thi iu khin thch hp ln RS, RW v bus d liu, cui cng l a E v 0. Hot ng chuyn i t cao xung thp cho php LCD nhn d liu hin thi trn cc ng iu khin cng nh trn bus d liu v xem nh l mt lnh. Tn hiu RS l tn hiu cho php chn thanh ghi (Register Select ). Khi RS=0, d liu c coi nh l mt lnh hay mt ch th c bit (nh l xa mn hnh, t v tr con tr). Khi RS=1, d liu c coi l d liu dng vn bn v s c hin th trn mn hnh. Tn hiu RW l tn hiu c/Ghi. Khi RW=1, thng tin trn bus d liu c ghi vo LCD. Khi RW=0, chng trnh s c LCD.Bus d liu gm 4 hoc 8 ng ty thuc vo ch hot ng m ngi s dng la chn ( y chng trnh s dng bus d liu 4 bit).3.5 Kt ni LCD 16x2 vi vi iu khin AT89C51Cn c vo cc chc nng ca kho st, kt ni LCD 16x2 vi vi iu khin AT89C51 nh sau: Chn 1 v chn 16 ni GND. Chn 2 v chn 15 ni +5V. Chn 3 ni vi 1 bin tr 10K iu chnh tng phn. Chn RS, R/W, EN ni vi 3 chn ca vi iu khin. 8 chn d liu kt ni 1 Port ca vi iu khin (nu truyn ch 8 bit).Chng 4KHO ST KHI BN PHM

4.1 Gii thiu chungH thng s dng mt bn phm ma trn gm c 4 ct (H1 n H4) v 4 ct (C1 n C4) c giao din nh sau:

Hnh 4.1: Giao din bn phm ma trn 4x4Trong : Cc phm s t 0 n 9: dng nhp s Phm OK: sau khi nhp m s kt thc bng phm ny, Phm Change : dng thay i m s Phm Unlock: dng m kha Phm Lock: Dng kha Phm Clear: Dng xa v nhp li4.2 Phng php qut phm iu khin bn phm ma trn ta s dng phng php qut phm. iu khin qut phm th phi xut d d liu 4 bit (trong c 1 bit mc logic thp v 3 bit cn li mc logic cao) ra cc ct ca ma trn phm kim tra xem c phm no c nhn hay khng. Nu c phm nhn th trong 4 bt c vo s c 1 bit mc logic thp v da trn c s thit lp ma trn phm. Nu khng c phm nhn th 4 bit c vo u mc cao, khi ta chuyn mc logic thp sang ct k tip d tm phm khc.4.3 Kt ni bn phm vi vi iu khin AT89C51Dng 1 dy bus 4 si kt ni ng ra ca bn phm vi 1 Port ca vi iu khin 89C51 kt ni vi Port 3: Port 3.0 kt ni ct 1 Port 3.1 kt ni ct 2 Port 3.2 kt ni ct 3 Port 3.3 kt ni ct 44.4 Chi tit khi bn phm trong mch

Hnh 4.2 S nguyn l ma trn phm

Hnh 4.3 Khi ma trn phm

Chng 5KHO ST KHI BO NG V KHI NG/M CA

5.1 Khi bo ng:Dng led thay th hin th thng qua chn p1.0 ,p1.1 v p1.2.5.2 khi m/ng ca:Dung led thay th hin th thng qua chn p1.3 v p1.5.

Chng 6KT QU THC HIN

6.1 Kt qu thc hin6.1.1 S nguyn l

6.1.2 Kt qu thi cng

6.1.3 Hot ng

6.1.4 Khuyt im ca mchMch cn c 1 s khuyt im nh:Khi RESET li th m s lu khng cn na, sau khi RESET phi ci li m mi, khi mt ngun cung cp th mch cng b RESET. Do tnh bo mt khng cao.Hng gii quyt: s dng vi iu khin AT89C2051 c sn 2KB EPROM bn trong hoc kt ni vi EEPROM ngoi lu m s ca ngi s dng trnh tnh trng mt m s khi mt in.Do ch bo ng bng tn hiu n hoc chung nn khi ngi dng cch xa ni bo ng th khng hay bit g v vic c ngi d mt khu hay khng. V vy hng pht trin ca n l thng bo cho ch nhn khi c ngi nhp m sai qu s ln qui nhn kp thi x l hoc thay i mt m. Vic thng bo t xa c th s dng sng radio hay thng bo qua in thoi, c th gi tin nhn chng hn...H thng kha s s dng LCD vi hng dn bng ting Anh, khng thn thin vi ngi dng lm. Ta c th s dng CGRAM v cc k t ting Vit c du gip ngi Vit d s dng hn.Mt khc vi 10 ch s t 0 n 9 th mc bo mt cha cao lm. Ta c th s dng cc k t nh a, b, c tng tnh bo mt cho h thng.Do l thit k u tin nn khng th trnh khi nhng li nht nh. Nhm thc hin ti xin chn thnh cm n s gip v hng dn ca cc thy gio v cc bn trong thi gian va qua. Mong rng s nhn c nhiu ng gp kin bn thit k ny v nhng bn thit k sau ngy cng c hon thin hn.

6.2 Hng pht trinTrn c s l thuyt hc, nhm thc hin ti thit k h thng kha vi tin cy c th chp nhn c da vo chc nng qun l chng trnh bng mt m trong my tnh vi quy m n gin hn. ng dng vo thc t, h thng ny cn cn c chnh sa tng tnh n nh v kt ni vi b phn c kh ng m ca. Hin nay, nhng h thng kim sot ra vo theo m s dng nhng hnh thc qun l tin tin hn nh: th t, vn tay,giao tip vi my tnh, iu khin t xa bng thit b thng minh smartphone... tuy nhin chi ph cn rt cao. Mt h thng qun l nh nhm thit k vn cn c nhng ng dng nht nh.

TI LIU THAM KHO

[1] Tng Vn On v Hong c Hi, H vi iu khin 8051, Nh xut bn Lao ng- X Hi, nm 2001.[2] Phm Minh H, K thut mch in t, Nh xut bn Khoa Hc- K Thut, nm 1997. [3] Ti liu v l thuyt, bi tp visual basic, l thuyt v vi iu khin AT89C51 v cc n tham kho t gio vin hng dn ThS. V Minh Thng.[4] Gio trnh mn mch v linh kin in t ca thy V Tun .[5] Tp thc hnh v slide bi ging mn k thut s ca thy Dng Tn Quc[6] Trang web: http://vidieukhien.net.[7] Trang web: http://tailieu.vn.[8] Trang web: http://www.dientuvietnam.net.[9] Trang web: http://www.Alldatasheet.com

Page 16 | 36

Khi vi x l

Khi bn phm

Khi hin th

Khi bo ng