bÁo cÁo ĐỀ tÀi mẠch ĐÈn giao thÔng
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NHN XT CA GIO VIN HNG DN
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MC LCTrang LI M U CHNG I: GII THIU V TI I.1: C s lu chn CHNG II: TNG QUAN V H VI IU KHIN II.1: Gii thiu II.2: Lch s pht trin ca cc loi vi iu khin II.3: Kho st b vi iu khin AT89C51 t ATMEL CORPOCATION II.3.1: Cu trc bn trong ca AT89C51 II.3.2: Tm tt phn cng II.3.3: Mch c bn 89C51 lm vic CHNG III: THIT K V LP TRNH III.1: Kt cu ca chng trnh III.2: Kt ni ngoi vi gm c III.2.1 H IC 78xx v IC 7805 III.2.2: IC 74245 - B nh m cho u vo. III.2.3: LED 7 on III.2.4 : in tr treo III.3: Phn thi cng mch III.3.1: S nguyn l mch iu khin n giao thng 4 5 5 5 5 5 6 7 8 14 14 14 15 15 16 17 18 19 19 2
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III.3.2: S board ca mch iu khin n giao thng III.3.3: S mach hin th n v thoi gian III.3.4: S board mch hin th n v thi gian III.4 Nguyn l hot ng ca mch III.5:Lu thut ton III.6: Phn lp trnh III6.1: Phng php lp trnh III.6.2: Chng trnh KT LUN
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LI NI UTrong nhng nm gn y theo s tin b ca khoa hc k thut, cng cuc cng nghip ha hin i ha t nc ang pht trin mnh m. Trc tnh hnh c kh nhiu yu cu cp bch v cng l nhng thch thc c t ra cho gii tr thc. tip tc dn dt s pht trin ca t nc ngy cng giu mnh, th phi u t cho gio dc, o to th h tr c kin thc p ng nhu cu ngy cng cao ca x hi. i hi phi nng cao cht lng o to, th phi a cc phng tin dy hc hin i vo trong ging ng, trng hc c nh vy th trnh con ngi ngy cng cao p ng c yu cu ca x hi. lm quen vi cng vic thit k, ch to v tm hiu cc v cc loi linh kin in t, chng em c cc thy c trong khoa CNTT giao cho n mn hc Thit k mch iu khin n giao thng ti ng t nhm cng c v kin thc trong qu trnh thc t. Sau khi nhn c ti, vi s hng dn ca thy Phm Ngc Hng cng vi s n lc ca bn thn, s tm ti nghin cu ti liu n nay n ca chng em v mt c bn hon thnh. Trong qu trnh thc hin d c gng nhng do thi gian cng nh trnh vn cn hn ch nn khng th trnh khi sai st. Vy em knh mong s ch bo gip v ng gp kin ca cc thy c n ca em c hon thin hn . Chng em xin chn thnh cm n thy Phm Ngc Hng cng cc thy c trong khoa gip chng em hon thnh n. Gio Vin Hng Dn: Phm Ngc Hng Nhm sinh vin thc hin: Hong Ngc Sn Chu Minh V Nguyn Vn Vi
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CHNG I : GII THIU V TII.1: C s la chn ti. t Vn (ng dng): Vi mi mt dn tc, kinh t pht trin th s pht trin v khoa hoc, k thut l tht s cn thit v c bit quan trng. Vi s pht trin mnh m ca kinh t nh hin nay, giao thng ang l mt bi ton kh i hi nhiu ngnh, nhiu cp phi quan tm, v tm ra cc hng gii quyt. lm gim bt nhng kh khn cng nh lm cho vic lu thng trn cc tuyn ng c thng thong v gim thiu ti nn, th vic t cc ct n ti cc ng v thi gian quy nh cho php i v cm i ca cc tuyn l c bit quan trng. i vi mt ng t, ti mi thi im trong ngy th s lu thng mi ng t la rt quan trng. V th, mt chng trnh iu khin n giao thng ng t c lu thng mt cch tt nht l cn thit v ht sc quan trng Vi nhng nhn nh nh th, chng em quyt nh chn ti giao thng ti ng t ny. . c s ng ca khoa in - in t Trng i Hc S Phm K Thut Hng Yn Nhm chng em tin hnh thc hin ti ny: Mch n Giao Thng ti ng t ng ph
CHNG II:TNG QUAN V H VI IU KHINII.1: Gi i thi u B vi iu khin vit tt l Micro-controller, l mch tch hp trn mt chip c th lp trnh c, dng iu khin hot ng ca mt h thng. Theo cc tp lnh ca ngi lp trnh, b vi iu khin tin hnh c, lu tr thng tin, x l thng tin, o thi gian v tin hnh ng m mt c cu no . Trong cc thit b in, in v in t dn dng, cc b vi iu khin, iu khin hot ng ca TV, my git, u c laser, in thai, l vi-ba Trong h thng sn xut t ng, b vi iu khin c s dng trong Robot, dy chuyn t ng. Cc h thng cng thng minh th vai tr ca h vi iu khin cng quan trng. II.2: L ch s ph t t in c a c c loi v iu hin. B vi iu khin thc ra, l mt loi vi x l trong tp hp cc b vi x l ni chung. B vi iu khin c pht trin t b vi x l, t nhng nm 70 do s 5
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pht trin v hon thin v cng ngh vi in t da trn k thut MOS (MetalOxide-Semiconductor) , mc tch hp ca cc linh kin bn dn trong mt chip ngy cng cao. Nm 1971 xut hin b vi x l 4 bit loi TMS1000 do cng ty texas Instruments va l ni pht minh va l nh sn xut. Nhn tng th th b vi x l ch c cha trn mt chip nhng chc nng cn thit x l chng trnh theo mt trnh t, cn tt c b phn ph tr khc cn thit nh : b nh d liu , b nh chng trnh , b chun i AID, khi iu khin, khi hin th, iu khin my in, hi ng h v lch l nhng linh kin nm bn ngoi c ni vo b vi x l. Mi n nm 1976 cng ty INTEL (Interlligen-Elictronics). Mi cho ra i b vi iu khin n chip u tin trn th gii vi tn gi 8048. Bn cnh b x l trung tm 8048 cn cha b nh d liu, b nh chng trnh, b m v pht thi gian cc cng vo v ra Digital trn mt chip. Cc cng ty khc cng ln lc cho ra i cc b vi iu khin 8bit tng t nh 8048 v hnh thnh h vi iu khin MCS-48 (Microcontroller-sustem-48). n nm 1980 cng ty INTEL cho ra i th h th hai ca b vi iu khin n chip vi tn gi 8051. V sau hng lot cc vi iu khin cng loi vi 8051 ra i v hnh thnh h vi iu khin MCS-51 . n nay h vi iu khin 8 bit MCS51 c n 250 thnh vin v hu ht cc cng ty hng dn hng u th gii ch to. ng u l cng ty INTEL v rt nhiu cng ty khc nh : AMD, SIEMENS, PHILIPS, DALLAS, OKI Ngoi ra cn c cc cng ty khc cng c nhng h vi iu khin ring nh: H 68HCOS ca cng ty Motorola H ST62 ca cng ty SGS-THOMSON H H8 ca cng ty Hitachi H pic cu cng ty Microchip II.3: Kh o s t vi iu hin AT C5 t ATMEL CORPOCATION
c im v chc nng hot ng ca cc IC h MSC-51 hon ton tng t nh nhau. y gii thiu IC 8951 l mt h IC vi iu khin do hng Intel ca M sn xut. Chng c cc c im chung nh sau: Cc c im ca 89C51 c tm tt nh sau: 4 KB ROM 4 KB EPROM bn trong. 128 Byte RAM ni. 4 Port xut nhp I/O 8 bit. 2 b nh thi 16 bit 6
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Mch giao tip ni tip. 64 KB vng nh m ngoi 64 KB vng nh d liu ngoi X l Boolean (hot ng trn bit n). 210 v tr nh c th nh v bit. 4s cho hot ng nhn hoc chia. II.3.1.Cu t c n t ong c a AT89C51. Phn chnh ca vi iu khin 8051 / 8031 l b x l trung tm (CPU: central processing unit ) bao gm : - Thanh ghi tch ly A - Thanh ghi tch ly ph B, dng cho php nhn v php chia - n v logic hc (ALU : Arithmetic Logical Unit ) - T trng thi chng trnh (PSW : Prorgam Status Word) - Bn bng thanh ghi - Con tr ngn xp Ngoi ra cn c b nh chng trnh, b gii m lnh, b iu khin thi gian v logic.c c ng ngoi t c c li vo b m 4 Kb ROM u khi ng i n t 128 byte RAM timer1 Timer 2
CPU
OSC
u khi i n BUS
4 c vo/ra ng
C ni ti ng p
TxD P0 P2 P1 P3
RxD
a chd li / u
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H nh II. : Cu t c II.3.2:Tm tt phn cng:U2 39 38 37 36 35 34 33 32 1 2 3 4 5 6 7 8 19 18 9 31 P0.0/AD0 P0.1/AD1 P0.2/AD2 P0.3/AD3 P0.4/AD4 P0.5/AD5 P0.6/AD6 P0.7/AD7 P1.0 P1.1 P1.2 P1.3 P1.4 P1.5 P1.6 P1.7 XTAL1 XTAL2 RST EA/VPP AT89C51
n t ong c a AT89C51
P2.0/A8 P2.1/A9 P2.2/A10 P2.3/A11 P2.4/A12 P2.5/A13 P2.6/A14 P2.7/A15 P3.0/RXD P3.1/TXD P3.2/INTO P3.3/INT1 P3.4/TO P3.5/T1 P3.6/WR P3.7/RD PSEN ALE/PROG
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Hnh II.2 : S chn c a IC89C51 AT89C51 c tt c 40 chn c chc nng nh cc ng xut nhp . Trong c 24 chn c tc dng kp (c ngha l mt chn c hai chc nng), mi ng c th hot ng nh ng xut nhp hoc nh ng iu khin hoc l thnh phn ca cc bus d liu v bus a ch. + Cc cng vo ra - Port 0 (Chn 32-39):l cng hai chiu dng 8 bit m, nh l cng ra, Port 0 c nhng cu hnh cng ng dn a ch, d liu truy xut ti chng trnh goi v b nh d liu. yu cu bn ngoi dng li trong lc kim tra chng trnh. - Port 1 (Chn 1-8): c cng hai chiu 8bit, trong php cng P1.0 v P1.1 c th thc hin i ti b nh thi/b m bn trong m ng vo(P1.0/T2) v hai b nh thi/b m truy xut ng vo(P1.1/T2EX). - Port 2 (Chn 21-28): c cng hai chiu 8bit, pht ra nhng a ch byte cao khc trong lc tm v t b nh chng trnh bn ngoi v truy xut t b nh d liu bn ngoi vic s dng 8bit a ch. Port 2 pht ra nhng ni dung ca thanh ghi c chc nng c bit P2 8
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- Port 3 (Chn 10-17): P3.0 RxD Chn pht d liu ca Port ni tip P3.1 TxD Chn thu d liu ca Port ni tip P3.2 INT0 Ng vo ngt ngoi 0 P3.3 INT1 Ng vo ngt ngoi 1 P3.4 T0 Ng vo b nh thi m 0 P3.5 T1 Ng vo b nh thi m 1 P3.6 WR iu khin ghi d liu vo RAM ngoi P3.7 RD iu khin c d liu t RAM ngoi + Reset (Chn 9): Chn reset c tc dng reset cho chp, mc tch cc ca chn ny l mc 1 , reset ta phi a mc 1 (5v) n chn ny vi thi gian ti thiu 2 chu k my ( tng ng 2s tng ng vi thch anh 12Mhz ). Sau y l mch reset. - RxD :nhn tn hiu kiu ni tip. - TxD :truyn tn hiu kiu ni tip. - /INT0: ngt ngoi 0. - /INT1: ngt ngoi 1. - T0: chn vo 0 ca b timer/counter 0. - T1: chn vo 0 ca b timer/counter 1. - /WR: ghi gi liu vo b nh ngoi. - /Rd: c gi liu t b nh ngoi. - XTAL1: chn vo mch khuch i dao ng. - XTAL2: chn ra t mch khuch i dao ng. - /PSEN: chn cho php c chng trnh ngoi (Rom ngoi).
reset bng tay
reset khi cp ngun
- Nt n: - Trng thi ca cc thanh ghi khi reset, khi reset th trng thi ca RAM ni khng b thay i 9
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+ Chn cho php cht a ch (ALE/PROG) Chn ALE c xung ng ra cht a ch Byet thp trong thi gian truy xut b nh ngoi. Chn ny c chng trnh xung ng vo trong khi tn hiu in ang chy. Trong iu khin bnh thng, chn ALE c xut ra vi mt gi tr bng 1/6 tn s ca mch dao ng v c th c s dng cho vic quy nh thi gian bn ngoi hoc mc ch m thi gian. Ghi nh, mt xung ALE c ngt qung trong khi mi truy xut t d liu b nh ngoi. Nu ra lnh, bnh thng ALE c th b hy bi vic ci dt bit 0 ca SFR c nh v tr 8EH + Chn cho php b nh chng trnh (PSEN:Program store Enable) PSEN c c xung nhn ti b nh chng trnh ngoi. Khi AT89C51RC ang thc hin m t b nh chng trnh ngoi, PSEN c thc hin vi chu k my tng gp i, tr phi hai hot ng PSEN c ngt qung trong thi gian truy xut ti b nh d liu bn ngoi. + Chn truy xut ngoi (EA/VPP) Kch hot truy xut ngoi, chn EA phi c ni vi GND khi s dng cc thit b t m truy cp t b nh chng trnh ngoi c nh v tr t 0000H ti FFFFH. + Chn tinh th thch anh XTAL XTAL1: ng vo ti mch dao ng khuch i ngc v ti mch in kha diu khin bn trong. XTAL2: ng ra t mch dao ng khuch i ngc. Thanh ghi cc chc nng c bit (SFR) Mt nh x trn b mt din tch ca b nh chip c gi l thanh ghi cc chc nng c bit. Ghi ch, khng phi l tt c cc a ch c s dng, v nhng a ch khng c s dng c th khng c b sung vo chip. c truy xut ti cc a ch s c tng hp y vo d liu ngu nhin, v truy xut c ghi s c hiu ng l m. + Thanh ghi b nh thi 2: iu khin v trng thi cc bit c cha ng vo thanh ghi T2CON v T2MOD. Thanh ghi ngt: khi ng nhng bit ngt ring bit c thc hin bi thanh ghi IE. TF2: Du hiu c trn 2 b nh thi t bi 2 b dnh thi c trn v phi c xa bi phn mm. TF2 s khng c dt khi RCLK = 1 hoc TCLK = 1 EXF2: 2 B nh thi du hiu ngoi khi mt ci c gi li hoc chy li bi mt t chi chuyn tip trn T2EX v EXEN2 = 1. khi 2 b nh thi trong 10
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c kch hot, EXF2 = 1 s l nguyn nhn CPU ti vector ti th tc 2 b nh thi trong. EXEN2 phi c xa bi phn mm. EXF2 khng phi nguyn nhn gy ngt trong b m ln/xung (DCEN = 1). RCLK Kch hot xung nhn, khi iu chnh, nguyn nhn cng ni tip c s dng 2 b nh thi c trn to xung cho xung nhn trong cng ni tip cho dng 1 v 3. RCLK = 0 l nguyn nhn c trn mt b nh thi c s dng cho vic nhn xung TCLK Kch hot truyn xung, khi iu chnh, nguyn nhn cng ni tip c dng c trn xung b nh thi 2 cho vic pht xung trong cng ni tip cho dng 1 v 3. TCLK = 0 nguyn nhn c trn b dnh thi 1 d c dng pht xung. -EXEN2 Kch hot b nh thi ngoi 2, mt ci c gi li hoc chy li xut nh l mt kt qu ca mt t chi chuyn tip trn T2EX neu1 b nh thi 2 khng c s dng to xung cho cng ni tip. EXEN2 = 0 l nguyn nhn b nh thi 2 l i kh nng c th xy ra ca T2EX TR2 iu khin bt u/dng li cho b nh thi 2. TR2 = 1 b nh thi bt u. C/T2 B nh thi hoc b m cho b nh thi 2. C/T2 = 0 cho chc nng b nh thi. C/T2 = 1 cho my m s kin ngoi. CP/RL2 Chn gi/chy li. CP/RL2 = 1 l do gi li cho xut hin trn t chi chuyn tip vo T2EX nu EXEN2 = 1. CP/RL2 = 0 nguyn nhn t ng chy li xut hin khi c trn b nh thi 2 hoc xut hin t chi chuyn tip vo T2EX khi EXEN2 = 1. khi RCLK hoc TCLK = 1, bit ny c l i v b nh thi b p t ng chy li trn c trn b nh thi 2. + Con tr ghi hai d liu: thun tin truy xut c hai b nh d liu bn trong v bn ngoi, 2 b ca 16bit con tr ghi d liu c cung cp: DP0 ca a ch thanh ghi cc chc nng c bit nh v tr 82H-83H v DP1 84H-85H. bit DPS = 0 trong cc thanh ghi ph cc chc nng c bit chon5DP0 v DP1 = 1 chn DP1. ngi s dng nn khi ng bit DPS tch hp gi tr trc khi truy xut tng ng vi con tr ghi d liu. C tt ngun(POF): c nh 4bit (PCON.4) vo PCON SFR. POF c iu chnh ti 1 trong khi bt ngun. n c th b iu chnh v v ng yn di phn mm iu khin v khng c gi to bi qu trnh khi ng li Thit b MCS_51 c mt khong a ch ring cho chng trnh v b nh d liu. + B nh chng trnh: - Nu chn EA c ni vi GND tt c chng trnh i v c hng v ti 11
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b nh ngoi. - Trong AT89C51RC, nu chn EA c ni vi Vcc th chng trnh v ti khong a ch 0000H-7FFFH i ti b nh chng trnh bn trong v i v ti a ch 8000H-FFFFH i ti b nh chuong trnh bn ngoi. B nh d liu: - AT89C51RC c b nh d liu bn trong vi 4 phn ring: + Thp hn 128 byte ca RAM (c a ch t 00H-7FH) c gn gi tr ngay lp tc hoc gin tip + Cao hn 128 byte RAM ( c a ch 80H-FFH) ch gn a ch bng cch gin tip + Cc thanh ghi c chc nng c bit (c a ch t 80H-FFH) ch c gn a ch bng cch trc tip + 256 byte RAM m rng (00H-FFH) c truy cut gin tip bi lnh MOVX, v vi bit EXTRAM c xa. + Phn cng b nh thi gim st: c d nh nh l phng php khi phc trong v tr ni m CPU c th b xo trn bi ch phn mm, n ph hp vi b m 13bit. Cch s dng b nh thi gim st: cho php n, ngi s dng phi vit 01EH v 0E1H trong dy ti thanh ghi WDTRST. Khi n c cho php, ngi s dng cn ti dch v ca n bi 01EH v 0E1H ti WDTRST ph hy c trn ca n. B m c trn 13bit khi n t ti 8191(1FFFH), v thit lp li cc thit b. khi n c cho php, n s gia tng chu k my trong khi mch dao ng ang chy. chy li n ngi dng phi vit 01EH v 0E1H ti WDTRST. WDTRST l thanh ghi ch vit. b m WDT khng th b c hay vit. B nh thi 0 v 1: B nh thi 0 v 1 trong AT89C51RC hot ng ging nh l b nh thi 0 v 1 trong AT89C51 v AT89C52. B nh thi 2: B nh thi 2 l b nh thi/b m 16bit n c th hot ng nh cc b nh thi khc hoc mt bin c m. b nh thi 2 gm 2 thanh ghi 8bit,TH2 v TL2. Xung nhp ra c th lp trnh c: Chu k hot ng l 50% c th c lp li chng trnh i ra bng chn P1.0. n c th l chng trnh vo xung bn ngoi cho b nh thi/b m 2 hoc cho ng ra vi 50% ch lm vic bin xung t 61Hz ti 4MHz vi mt tn s hot ng 16MHz.Cu hnh ca b nh thi/b m 2 nh l mt hm sin, bit C/T2 (T2CON.1) phi c xa v bit T2OE (T2MOD.1) phi 12
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c iu chnh. Bit TR2 (T2CON.2) bt u v dng b nh thi. Tn s xung ra ph thuc vo tn s dao ng v gi tr np li ca thanh ghi b nh thi 2 (RCAP2H,RCAP2L). ta c Tn s xung ra = ( tn s dao ng) /(4*[65536-(RCAP2H,RACP2L)]) Trong ch xung ra, bn quay b nh thi 2 s khng c pht ng ngt. + Ch ngt: AT89C51RC c tng cng 6 vector ngt: 2 ngt ngoi (INT0 v INT1), 3 b nh thi ngt (b nh thi 0,1 v 2) v cng ngt ni tip. Mi ngun ngt c th cho php ring l hoc ngn chn bi qu trnh ci t hoc xa b 1 bit trong thanh ghi cc chc nng c bit (SFR) IE. B nh thi ngt 2 c khi ng bi ton t logic OR ca cc bit TF2 v EXF2 trong thanh ghi T2CON. Nhng ci c khng nhng c xa bi phn cng khi th tc ca dch v c hng ti. thc ra, th tc dch v c th c nh r l TF2 hay EXF2 d khi ng ngt, v bit s c xa trong phn mm. C b nh thi 0 v 1, TF0 v TF1, c iu chnh S5P2 ca chu k trong b nh thi c trn. c im dao ng: XTAL1 v XTAL2 l ng ra v ng vo, theo th t c nh sn, iu khin thit b t mt ngun xung ngoi. XTAL2 s khng c lien kt bn tri trong khi XTAL1 c iu khin Ch ngh: Trong ch ngh, CPU ngh trong khi tt c cc chip ngoi vi u hot ng. ch ny c gi ra bng phn mm. Dung lng trn chip RAM v tt c SFR c thay i, ch ngh c th bn trong cho php ngt hoc ch lp li ca phn cng. Ch khi ch ngh c kt thc bi ch lp li ca phn cng, cc thit b thong thng c chy lai chng trnh t phn tt bn tri.
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II.3.3: Mch c
n
C5 lm vi c:
Hnh II.3 : Mch c
n c a IC
C51
CHNG III: THIT K V LP TRNHIII.1: Kt cu c a chng t nh Chng trnh gm hai chng trnh con - chng trnh 1 chng trnh ban ngy - chng trnh 2 chng trnh ban m t 23h n 5h sng + chng trnh 1 l chng trnh c thi gian n 25s, n xanh 30s n vng 5s 14
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+ chng trnh 2 l chng trnh ch c n vng nhp nhy - chn chng trnh ta phi thit lp chng trnh v reset h thng qua nt nhn reset III.2: Kt ni ngoi vi gm c: III.2.1-H IC 78xx v IC 7805 Vi nhng mch in khng i hi n nh ca in p qu cao, s dng IC n p thng c ngi thit k s dng v mch in kh n gin. Cc loi n p thng c s dng l IC 78xx, vi xx l in p cn n p. V d 7805 n p 5V, 7812 n p 12V. Vic dng cc loi IC n p 78xx tng t nhau.
* Nhng dng se i c a 7 XX: - LA7805 IC n p 5V - LA7806 IC n p 6V - LA7808 IC n p 8V y l dng cho in p ra tng ng vi dng l 1A. Hnh nh mt IC 7805 c 3 chn:
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S khi ca IC 7805. III.2.2: IC 74245 - B nh m cho u vo.
Chc nng: - y l mt loi IC s kh ph bin, tn gi chung l 74245, ty thuc vo tn s p ng v cng ty sn xut s c cc tn hi khc nhau nh 74HC245, 74HCT245... nhng khi loi b cc k t gia, vn chung l 74245. - Bi ton: Khi ta cn kim sot mt s lng trng thi, cm bin tip im m s u cn kim sot ln ti > 10 im, c khi ti 40 im, bn khng th ni tt c cc cm bin ny vi vi x l v khng th Port. V vy, chng 16
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ta phi s dng c d liu theo kiu BUS v dng 74245 nh l b nh m u vo cho vi x l. C c thc hot ng: - S nguyn l: Nh s trn, trong A ( u vo Vi x l), B ( u vo ly tn hiu t sensor), Chn AB/BA ni Gnd v quan trng nht l chn CE (Chip enable). - Vi s trn, ti gii thiu cc bn s dng 2 IC 74HCT235 c d liu trng thi on/off t 16 cm bin sensor khc nhau
PORT A : u ra ca 74245 v c u vo u vo ca vi x l, tt c cc PORT A ca cc IC 74245 c u chung to thnh ng d liu BUS 8bit. PORT B : u vo ca 74245 , c u vo cc trang thi on/off ca sensror, mi mt PIN c u vi mt sensor khc nhau, v lu , nu sensor cha c in tr Pullup th phi thm mt dy din tr Pullup vo PORT B lun m bo trng thi logic cho PORTB. CE : Chn chn chp, trng thi tch cc thp, khi mun PORT A = PORT B th CE=0 (c c IC 74245 h c t u c CE= ngn hng cho PORTA=PORTB, nu qun iu ny, d liu s lung tung, khng kim sot c nh " C mt li ra, ch va mt ngi i m ta m n 4 ca, 4 ngi chen chc nhau i
III.2.3: LED 7 on Hin th dng led 7 on loi anode chung ng vi IC gii m 74245 c mc tch cc l mc 0 ( mc thp). loi anode chung ( anode ca n c ni ln +5V, on no sng ta ni u cathode a on xung mc thp thng qua in tr hn dng. Hin th dng led 7 on loi katot chung ng vi IC gii m 7448 c mc tch cc l mc 1 ( mc cao). loi katot chung ( katot ca n c ni ln GND)
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III.2.4 : i n tr treo - Vi cc chn vi chn 1 ni ngun 5vdc 8 chn cn li dng ni vo 8 chn ra ca vi iukhin 89c51 c tc dng lm tng dng in lm cho dng in khe hn mch ny chng ta dng in tr 10k
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III.3: Phn thi cng mch III.3.1: S nguyn l mch iu khin n giao thng
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III.3.2: S board c a mach iu khin n giao thng
III.3.3: S mch hin th n v thi gian
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III.3.4: S board mch hin th n v thi gian
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III.4 Nguy n l hot ng c a mch Nguyn l hot ng ca mch iu khin n giao thng ti ng t: T mch ngun dng IC7805 cung cp ngun n nh +5V cho mch, sau khi IC89C51 c cp ngun +5V th t cng P0 ca IC89C51 s xut d liu ra IC74AC245 sau t IC74AC245 s xut d liu ra led 7 thanh hin th thi gian m. T cng P2 v P3 ca 89C51 d liu c xut vo IC3, IC4 ca 74245 xut tn hiu ra led n hin th n bo giao thng, xanh, vng, . Ty theo ch ban ngy hay ban m( chn ch ban ngy hay ban m bng cch tc ng vo nt nhn S2). III.5:Lu thut ton
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Lu chng t nh
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Lu chng t nh 2
III.6: Phn lp trnh III.6. : Phng ph p lp trnh Phng php lp trnh: S dng IC AT89C51 lp trnh C rt nhiu phn mm h tr son tho vi nhiu ngn nh khc nhau v bin dch, nap... Nh phn mm Ride, Raisonance, Prog-studio-setup, KeilC,... Vi ngn ng Assembly, C, C++... Trong n ny chng em s dng phn mm Keilc vi ngn ng son tho C son tho. 25
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III.6.2: Chng t nh #include #define dc P2_0 #define vc P2_1 #define xc P2_2 #define l1c P2_3 #define l2c P2_4
#define dp P3_0 #define vp P3_1 #define xp P3_2 #define l1p P3_3 #define l2p P3_4
#define b P1_0 #define led1 P1_2 #define led2 P1_3 bit n=0; char M[]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90}; unsigned char a1,a2,a3,a4,sl; char p; unsigned char tdc,tvc,txc,tdp,tvp,txp,temp1c,temp2c,temp1p,temp2p; 26
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void delay(unsigned int x); void dislay(); void init(); void ngat(); ////////////////////////////////////////// void pwm() interrupt 1 { //chuong trinh viet o day ngat(); } /////////////////// void main(){ init(); //temp1=2;temp2=9; while(1){ if(b==0){ delay(1000); if (b==0){ p=60; txc=31;tdp=26;tvp=6; tdc=26;tvc=6;txp=31; while(b==0); 27
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n=~n; } }
if(n==0){ led1=0;led2=1; dislay(); } } }
///////////////////////////////////////////////////////////////////////// void init(){led1=0; led2=1; l1c=l2c=l1p=l2p=1; dc=vc=xc=dp=vp=xp=0; P0=0xff; //kahi bao timer 0 che do 1 16bit TMOD=0x01; TH0=0x3c; TL0=0xb0; 28
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TF0=0; ET0=1; //cho phep ngat timer0 EA=1; //ngat toan cuc TR0=1; //cho phep chay timer p=60; txc=31;tdp=26;tvp=6; tdc=26;tvc=6;txp=31; } void delay(unsigned int x){ unsigned int i; for(i=0;i