KIN TRC MY TNH

BI TP LN KIN TRC V NGUYN L LM VIC VI X L 32BIT INTEL LP CT 1 NHM 4 GIO VIN HNG DN: SINH VIN THC HIN : 1. VN SANG 2. NGUYN NGC QU 3. HONG VN QUYT 4. ON HI NAM 5. PHM CH THIN

MC LC Trang Chng 1. Tng quan v VXL Intel3 1.1 VXL Intel 32 bit 3 1.2 Lch s pht trin vi x l Intel3 Chng 2. Kin trc IA-32 (x86)132.1 Khi nim 132.2 Chc nng ca IA-3213 Chng 3. Kin trc v nguyn l lm vic ca VXL 80386143.1 c im chung ca vi x l 80386143.2 VXL 80386 c 20 chn tn hiu173.3 Cc tn hiu ngt173.3.1 Cc tn hiu xc nh chu k bus173.3.2 Cc tn hiu iu khin bus183.3.3 Cc tn hiu trng ti bus183.4 Cc thanh ghi a nng, thanh ghi tr, thanh ghi c193.4.1 Cc thanh ghi iu khin203.4.2 Cc thanh ghi on203.4.3 Cc thanh ghi kim tra v g ri213.5 T chc b nh ca 80386223.5.1 T chc phn on223.5.2 T chc phn trang223.6 Khng gian nh233.7 Ch thc ca 80386233.8 Ch bo v phn on243.8.1 Cc khi nim c bn243.8.2 Bng cc m t on263.8.3 Cc m t v b chn on nh293.8.3.1 Cc b m t on293.8.3.2 B chn on323.8.3.3 Bo v b nh323.8.3.4 Ch phn trang b nh333.8.3.4.1 Th mc trang, bng trang v trang333.8.3.4.2 Tnh a ch vt l trong ch trang343.8.3.4.3 Vai tr ca h iu hnh trong qun l trang363.9 Ch 8086 o373.10 Ch thc ca 80386393.11 Cc thay i chnh 80386393.12 Cc thanh ghi a nng lm con tr40 Chng 4. Kin trc Pentium43 4.1 Thanh ghi (registers)43 4.2 Truy nhp b nh (Accessing Memory)44 4.3 Kin trc pentum pro v sau 45Ti liu tham kho46Danh mc hnhHnh 1. VXL Intel 40048Hnh 2. VXL Intel 80089Hnh 3. VXL Intel 8028610Hnh 4. VXL 8038611Hnh 5. VXL 8048612Hnh 6. VXL Pentium13Hnh 7. VXL Pentium II14Hnh 8. VXL Pentium III15Hnh 9. VXL Pentium IV15Hnh 10. S khi 8038620Hnh 11. Cch t chc h phn cp c quyn29Hnh 12. Mi lin h gia cc thanh ghi v cc b m t on32Hnh 13. Tnh a ch vt l trong ch phn trang39

Chng 1. Tng quan v VXL Intel1.1 VXL Intel 32 bit.Kin trc VXL 32 bit Intel ph bin c 80386/80486, Pentium, Pentium Pro, Pentium II, Pentium III, Pentium IV, Pentium M, Core, Celeron M, Celeron D.

1.2 Lch s pht trin vi x l Intel.Khi cng ngh c ci thin trong nhng nm qua, pht trin mt cuc chy ua c c nhng b vi x l u tin (c th s dng c) trn mt mch tch hp duy nht.Khi c th t khong 10000 bng bn dn (transistors) trn mt vi mch duy nht (IC), sau chng ta phi c mch (circuitry) t mt b x l n gin (simple processor) trn mt IC n gin .Nm 1970, Intel cho ra i chip vi x l u tin 4004: di t x l 4 bit. Bus d liu 4 bit, bus a ch 12 bit (dng chung vi bus d liu). Kch thc 22mm2, 16 chn, cha 2250 transitors.Hinh 1 VXL intel 4004Nm 1972, Intel cho ra i chip vi x l 8008. di t x l: 8 bit. Bus d liu 8 bit, bus a ch 14 bit (dng chung vi bus d liu). Tn s lm vic 300Khz, 18 chn, cha 3300 transitors.

Hnh 2 VXL intel 8008Nm 1976, Zilog cho ra i chip vi x l Z80: di t x l: 8 bit. Bus d liu 8 bit, bus a ch 16 bit (dng chung vi bus d liu). Tn s lm vic 2.5, 4, 6, 8 v 10 Mhz; 40 chn.Nm 1982, Intel cho ra i chip vi x l 80286. di t x l: 16 bit. Bus d liu 16 bit, bus a ch 24 bit (dng chung vi bus d liu). B nh max: 16MB. Tn s lm vic 6-25Mhz.

Hnh 3 VXL intel 80286Nm 1985, Intel cho ra i chip vi x l 80386: di t x l: 32 bit. Bus d liu 32 bit, bus a ch 32 bit (dng chung vi bus d liu). B nh max: 4GB. Tn s lm vic: 16-33Mhz.

Hnh 4 VXL intel 80386Nm 1989, Intel cho ra i chip vi x l 80486: di t x l: 32 bit. Bus d liu 32 bit, bus a ch 32 bit (dng chung vi bus d liu). B nh max: 4GB. Tn s lm vic: 25-100Mhz. Tch hp cache L1 8K. Tch hp ng x l s thc 80487.

Hnh 5 VXL intel 80486Nm 1993, Intel cho ra i chip vi x l Pentium: di t x l: 32 bit. Bus d liu 32 bit, bus a ch 32 bit (dng chung vi bus d liu). B nh max: 4GB. Tn s lm vic 60, 75, 90, 120Mhz. Tch hp cache I-L1 8K v D-L1 8K. H tr tp lnh x l multimedia MMX.

Hnh 6 VXL intel pentium Nm 1997, Intel cho ra i chip vi x l Pentium II. Tn s lm vic 233-450 Mhz. Tch hp cache I-L1 16-32K v D-L1 16-32K. Tch hp cache L2 256-512K. S dng khe cm kiu slot I.

Hnh 7 VXL intel pentium IINm 1999, Intel cho ra l chip vi x l Pentium III. Tn s lm vic 450Mhz-1.4Ghz Tch hp cache L1, L2. Gii thiu tp lnh SSE (Streaming SIMD Extensions).

Hnh 8 VXL intel pentium IIINm 2000, Intel cho ra i chip vi x l Pentitum IV. Tn s lm vic 1.5-3.8 Ghz, cng ngh 180-130nm. H tr cc tp lnh tin tin SSE, SSE2, SSE3. Mt s phin bn mi nht h tr cng ngh siu phn lung v o ha.Hnh 9 VXL pentium IVNm 2003, Intel cho ra i chip vi x l Pentium M. Cng ngh 130-90nm. Tn s lm vic 900Mhz 2.26Ghz. Thit k dnh ring cho my xch tay. Cache L1 32K, L2 n 2MB. H tr cc tp lnh tin tin MMX, SSE, SSE2. Cng ngh qun l ngun tin tin Intel Speedstep.

Chng 2. Kin trc IA-32 (x86)2.1 Khi nim IA-32 (Intel Architecture, 32 bit) cn c gi l x86, x86-32 hay i386 l mtkin trctp lnh ca intel ng dng rt thnh cng trong mng vi x l.kin trcny xut hin u tin trong vi x l ni ting ca Intel, 80386, gi ykin trcny c thit lp cho hu ht cc h vi x l trn th gii.2.2 Chc nng ca IA-32IA-32 c kh nng tng thch ngc y v h tr (m rng) nhng x l 64 bit, c gi l Intel 64 ca Intel hay AMD64 ca AMD (cn c gi l x86-64 v khng lin quan g nkin trcIA-64 c p dng trong nhng dng Itanium ( vi x l cho my ch ca Intel)). Chnh do tnh tng thch ngc rt tt v s h tr m rng x l 64 bit mkin trcIA-32 vn c duy tr v s dng rng ri. Cc thanh ghi bn trong c rng 32 bit. X l cc php ton s nguyn vi 32 bit. C 3 c ch lm vic. Ch 8086 thc: lm vic nh mt b x l 8086 n nhim 16 bit. Ch o: lm vic nh nhiu b vi x l 8086 a nhim 16 bit. Ch bo v l vic a nhim 32 bit. X l cc php ton s du chm ng.

Chng 3. Kin trc v nguyn l lm vic ca VXL 803863.1 c im chung ca VXL 80386i386 l vit tt ca Intel 80386 hay thm ch cn vit tt l 386, l dng vi x l xut hin t nm 1986 ca Intel da trn kin trc vi x l 32bit.Cc i386 c a ra trong thng mi 1985, nhng y chc nng th c a ra u tin vo nm 1986.Thng 5 nm 2006 Intel cng b rng sn phm ca 386 s chm dt vo cui thng chn nm 2007. V n by gi chng ta thy cc CPU ca Intel v cc hng khc a s l dng 64bit. Tuy nhin do cc phn mm ng dng trn nn tng 32bit vn ang cn qu thnh hnh v phn mm vn cha khai thc ht c cc tnh nng ni tri ca 64bit.T vi x l 80386 l khi u ca cc vi x l 32 bt .Tc l chng c c cc b s liu v bus a ch u c rng 32 bt .cc vi x ly ny h tr rt mnh cho cc h iu hnh a nhim 80386 c dung cho cc my IBM PS/2 80 u tin v nhiu my nhi khc.chng ta c th lit k vi c im chnh ca vi x l 80386 nh sau: Bus d liu rng 32 bt nn c th truy xut 4 byte s liu mt lc Bus a ch rng 32 bt nn c th qun l c n 232=4 Gbyte nh vt l . Vi trn 275.000 transistor v tc xung ng h 33 MHz, 80386 c tc 11MIPS,tc l vi 11 triu lnh trong 1 giy (million instructions per second), cho php h tr cc chc nng c bn nh 80286 bao gm qun l b v bo v b nh nn dng tt cho cc h iu hnh a nhim .V c mch tnh s hc logic ALU 32 bt nn n c th lm vic trc tip vi t d liu di 32 bt .B nh ca 80386 c th ln ti 4 Gbyte v mt chng trnh c th c ti 16.384 on nn khng gian a ch o l 16.384 .4 Gbyte = 64 Tbyte nh .S cc nhm chn tn hiu v cc s khi hnh sau:

3.2 Vi x l 80386 c 20 chn tn hiu :D0-D31,A0-A31,A31-A3 80386 dng in th Vss V.cc=5.0v tiu th dng trung bnh 550mA-phin bn tn s 25 MHZ,500 mA-phin bn tn s 25MHZ,600Ma-phin bn 20MHZ -D0-D31 l 32 bt s liu .Ty theo mc tn hiu NA trn bus iu khin ,thng tin truyn qua bus s liu c th l 32 bt hay 16. -A0-A31 l 32 bt a ch .cc tin hiu BEO-BE3 cho bit byte s liu no c truyn . s liu di 32 bt th c 4 tn hiu ny phi mc tch cc thp. -CLK2 l li vo xung nhp cp cho vi x l , n c chia 2 bn trong thnh PCLK ng b qu trnh thc hin lnh .3.3 Cc tn hiu ngt :INTR v NMI. -RESET :a vi x l vo trng thi khi ng li .Chn ny phi mc tch cc t nht 15 chu k CLK2, n nhy vi mc xung v phi ng b vi CLK2.3.3.1Cc tn hiu xc nh chu k bus :y l tn hiu ra 3 trng thi ,xc nh cc loi chu k bus W/R phn bit gia chu k ghi v c .D/C phn bit gia chu k s liu va chu k iu khin .M/IO phn bit gia chu k nh v cng vo ra .Bng sau ch ra cc chu k bus tng ng vi cc tn hiu trng thi .M/IOD/CW/RChu k busLOCK?000Tr li ngt c011Khng xy ra-000c vo raKhng011Vit vo raKhng100c m lnhKhng101Dng Khng110c b nh C mt s chu k1 11Vit b nhC mt s chu k

3.3.2 Cc tn hiu iu khin bus :+ ADS l tn hiu ra 3 trng thi , cho bit chu k bus bt u v cc tn hiu W/R, D/C, M/IO, BEO-BE3 ,A2-A31 c a ra cc chn x l + REALY l tn hiu vo , cho bit chu k bus kt thc . + NA (next address) l tn hiu vo dng cho phng php nh a ch ng ng .mc tch cc thp bo cho CPU bit l h thng sn sng , nhn gi tr mi ca cc tn hiu W/R, D/C, M/IO, BEO-BE3,A2-A31, mc d chu k bus hin hnh cha c tr li bng tn hiu REALY=0. +BS16 l tn hiu vo , cho php vi x l ni vi bus s liu 32 hoc 16 bt .Khi BS16=0, lm cho chu k hin hnh ch s dng 16 bt thp ca bus s liu D0-D15 (tng ng vi BEO-BE1) .Nu trong chu k hin ti BEO=0 v BE1=0 th a tn hiu BS16=0 khng nh hng .Nhng nu BE2=0 m a tn hiu BS16=0 th CPU s t ng thch nghi chuyn cc byte ny sang D0-D15.Tn hiu BS16 khng c mc tch cc trong chu k lm vic vi b ng x l .3.3.3 Cc tin hiu trng ti bus : + HOLD l tn hiu vo do mt thit b ch khc a n yu cu lm ch bus .Nu ng thi c c tn hiu RESET th tn hiu s c u tin ln hn . + HLDA 80386 a ra tn hiu ny tr li tn hiu HOLD v chuyn v trng thi tr li HOLD . trng thi ny vi x l ch iu khin tn hiu HLDA cn tt c cc tn hiu ra 2 chiu khc u trng thi tr khng cao.80386 cng c 2 ch hot ng ,ch thc v ch bo v .Ngoi ra cn c mt ch hot ng 8086 o cho phep d dng chuyn qua li gia cc nhim v trong ch bo v v ch thc .Cc thanh ghi trong 80386 v di 32 bt nn c k hiu them ch E (extended) u , v d EAX, EBX Mt c im mi l 80386 c cc thanh ghi g ri .Mt b phn g ri mm c th np cc a ch im dng trong chng h tr cho vic g ri .80386 c th c ra lnh dng khi n v a ch trong b x l tnh ton mt a ch tuyn tnh trng hp vi mt trong cc a ch cc thanh ghi g ri.3.4 Cc thanh ghi a nng, thanh ghi tr, thanh ghi c. -Cc thanh ghi nay rng 32 bt , phn 16 bt thp cung cc byte cao v thp trong cc thanh ghi m rng vn gi nh c l AH v AL s bt c trong thanh ghi c cng nhiu hn.EAXAHALEBXBHBLECXCHCLEDXDHDLESISIEDIDIEBPBPESPSPEIPIPEFLAGSFLAG VM:Ch o TF:C by RF:C hi phc SF:C du NT:C lng nhim v ZF:C zero I/O PL:Mc c quyn AF:C nh ph OF:C trn PF:C chn l DF:C hng CF:C nh IF:C ngt 3.4.1 Cc thanh ghi iu khin l thanh ghi iu khin 32 bt nh cc thanh ghi khc ca vi x l 32 bt ny .Gm cc b phn :CR0, CR1, CR2 , CR3 .Trong + CR0 :TS .EM , MP ,PE + CR1: c nhim v d tr + CR2: a ch tuyn tnh trang nh c li + CR3 : 20 bt a ch c s th mc trang nh v 11 bt d tr3.4.2 Cc thanh ghi on Phn h 16 bt Phn kn(c np bi chng trnh) (c vi x l np t ng) B chn quyn truy nhp a ch c s di on 16 bt 12 bt 32 bt 28 bt CS DS SS ES FS GS3.4.3 Cc thanh ghi kim tra v g ri DR0 a ch tuyn tnh ca im dng 0 DR1 a ch tuyn tnh ca im dng 1Cc thanh ghi g ri DR2 a ch tuyn tnh ca im dng 2 DR3 a ch tuyn tnh ca im dng 3 DR4 D tr DR5 D tr TR6 T iu khin kim tra Thanh ghi kim tra TR7 T trng thi kim tra16 bt thp ca thanh ghi iu khin CR0 l t trang thi my MSW .Vi x l 80386 cng chuyn sang ch bo v bng vic t bt LSB ca thanh ghi ny ti 1 .Thanh ghi CR1 c d tr v thanh ghi CR2 v CR3 c dng cho ch bo v trang.-Thanh ghi qun l b nh : gm c cc thanh ghi GDTR, LDTR, IDTR, TR, c chc nng ging nh b vi x l 80286 ch khc ch :i ch c s 32 bt v gi tri gii hn l 20 bt-Thanh ghi trng thi SR v thanh ghi im chng trnh :cng c nng ln 32 bt gm 16 bt thp nh trong VXL 80286 v 16 bt cao.3.5 T chc b nh ca 80386.-B nh ca 80386 c t chc theo byte (8 bit) v ( 16 bit) hay t kp (32 bt). Ngoi ch thc , cng c nhng ch bo v nh sau :3.5.1 T chc phn on , chia b nh thnh tng on ring bit dnh cho m lnh , s liu v ngn xp .iu ny cho php nhiu chng trnh chy cng lc m khng nh hng ln nhau . T chc phn on rt tin li cho vic lp trnh m-dun , l cng c hu dng cho ngi lp trnh ng dng.3.5.2 T chc phn trang , s dng b nh o gm nhiu trang c kch thc nh v c nh .Do ch mt phn chng trnh ang chy c t vo b nh khi cn thit.iu ny cho php tch bit cc nhim v ang cng chy mt lc .T chc theo trang th thun li cho vic lp trnh h thng khi cn qun l b nh vt l.-Qun l b nh trong 80386 cn cho php to mt ch 8086 o l mt nhim v c bit chy trong ch bo v .Lc ny b VXL m phng hon ton vi x l 8086 v nh vy cho php nhiu chng trnh 8086 o c th chy song song ng thi .Do cc th h vi x l 486 v pentium tip theo cng lm vic trn nguyn tc ny nn ch bo v v qun l b nh ca VXL 80386 c tm hiu chi tit l mt vic lm cn thit. 3.6 Khng gian nh :80386 c 3 loi a ch : + a ch lgic hay cn c gi l a ch o :a ch logic co 2 phn l b chn v lch offset.B chn l ni dung ca cc thanh ghi on .Offset c to nn t tng th ca 3 thnh phn : a ch c s , chi s v dch chuyn (base , index v displasement).Mi nhim v c nhiu nht 214=16 k b chn .Offset l mt s 32 bt c th ln n 232 =4 Gbyte .Nh vy ,mt nhim v c cc i 214 x 232 =246 = 64 Gbyte.Trong khi khng gian a ch vt l ca 80386 l 4Gbyte th khng gian a ch logic l 64Gbyte. + n v qun l on chuyn a ch logic thnh 32 bt a ch tuyn tnh .Nu n v qun l trang khng c php th 32 bt a ch tuyn tnh ny tng ng vi cc a ch vt l xut hin cc chn a ch ca 80386 .Nu n v qun l trang c php th n s chuyn 32 bt a ch tuyn tnh thnh cc a ch trang.3.7 Ch thc ca 80386 Sau khi khi ng my tnh , 80386 cng nhy ngay vo ch thc .Ti y n c cu trc nh 8086 nhng c th xm nhp vo thanh ghi 32 bt .C ch nh a ch cung nh kch thc b nh cng nh ch thc trong 80266 .Kich thc cc i ca b nh l 1 Mbyte ,v vy ch c cc dy a ch t A2 n A 19 v BEO n BE3 l tch cc .a ch vt l c tnh bng cch dch tri ni dung thanh ghi on 4 bit ri cng vi a ch hiu dng.Nh vy ch thc ,b nh c a ch t 0000 0000 n 0010 FFFFh .Vic dich tri thanh ghi on thanh 4 bt ngm nh rng cc on nh bt u cc a ch khc nhau 16 byte . di ca mt on ch thc l 64 kbyte .Cc on c th gi ln nhau cho php ngi lp trnh ti thiu ha dung lng b nh cn cho chng

Ch bo v Khi mun chuyn sang ch bo v phi t bit thp nht PE trong thanh ghi iu khin CR0 ln 1 .Ch bo v trong 386 c 2 loi : bo v phn on v bo v phn trang .S khc nhau gia ch thc v ch bo v l cch tnh a c s . ch bo v ,vi x l dng b chn xc nh a ch s nhm tm ti b m t on .Trong b m t on cha 32 bt a ch c s .Sau a ch tuyn tnh , chnh l a ch vt l ,cng c tnh bng a ch c s v ofset .Phn chia thnh trang l mt c ch ch chi php trong ch bo v .n v qun l theo trang s bin i 32 bt tuyn tnh tm c nh m t on thnh cc a ch trang vt l.3.8 Ch bo v phn on trong 803863.8.1 Cc khi nim c bn -on nh v cc mc c quyn: ch bo v phn on trong 80386 cng ging nh trong 80286. Mt trong nhng xut pht im ca vic phn on b nh l do yu cu bo v cc nhim v khc nhau trong cc chng trnh. Gii php tng qut cho b nh lc ny l nh ngha nhiu khng gian a ch hon thnh c lp gi l cc on nh cho mi nhim v. mi giai on gm cc a ch tuyn tnh k tip nhau t 0 n gi tr ti a. Nh vy mi on c di xc nh, chiu di ny c th thay i trong thi gian thc thi chng trnh.

Hnh 11 Cch t chc h phn cp c quyn

Ging nh trong 80286, mi on nh cng c gn cho mt trong bn mc c quyn c nh s t 0-3 vi mc c quyn gim dn nh ch ra trn hnh 2.23.mc c quyn gn cho mt chng trnh cho bit mt chng trnh c thm quyn l nhng g khi n c thc hin mt nhim v. Mc 0 l mc c quyn cao nht gm cc chng trnh qun l ti nguyn h thng v b nh.Li phi gn, c kh nng vn hnh tt, khng b hng do phn mm khc. Cc chng trnh con trong BIOS thuc loi ny.Mc mt gm cc phn mm lin quan n cc phn mm h thng qun l thit b v cc cng vo ra, thit lp mc u tin gia cc nhim v, lm thun ton tro i (swapping) v cc trnh iu khin thit b. Mc 2 bao gm cc chng trnh qun l tp tin, cc th vin. cc chng trnh h iu hnh thuc mc ny. Mc 3 dn cho cc chng trnh ng dng l mc thp nht.H phn cp ny quy nh chng trnh c th thm nhp vo bt c nhim v no c mc c quyn thp hn nhng nhy vo mt nhim v c mc c quyn cao hn th chng trnh phi qua b m t ca nu khng s xy ra ngoi l.H thng phn bit trng thy cc mc c quyn nh sau:Mc c quyn yu cn RPL l gi tr cc bt RPL c lu gi ti thanh ghi on (bt chn)Mc c quyn hin ti CPL ca mt nhim v ang thc hin, c gi tr bng mc c quyn ca on lnh ang chy.n chnh l cc bt RPL ca b chn on ang chy. B s l c th thay i CPL nu iu khin chng trnh c chuyn cho mt on m lnh c mc c quyn khc.Mc c quyn b m t DPL l mc c quyn thp nht, cn c nhim v c th thm nhp vo b m t.l gi tr lu gi ti trng DPL trong b m t on. l mc c quyn ca on nh cn thm nhp.Mc c quyn hiu dng EPL l mc c quyn thp nht trong thng s RPL v DPL.3.8.2 Bng cc b m t on: ging nh trong 80286, bng cc b m t cha tt c thng tin v cc on nh bng cc b m t on. c 3 loi bng: bng cc b m t ton c GDT, bng cc b m t c b LDT v bng cc b m t ngt IDT. Tt c cc bng c di t 8 byte n 64 kbyte.- Bng GDT di 64 kbyte (8byte x 213=216 byte) c th qun l c 213 on nh trong khng gian nh ton cc.khng gian ny lu tr cc m lnh h iu hnh v d lieuj h iu hnh, tr b m t ngt, bng ny cha tt c cc b m t m tt c nhim v ca h thng u thm thp c. GDT l mt bng duy nht, a ch c s v di GDT c cha trong thanh ghi h thng GDTR ( thanh ghi bng cc b m t ton cc). - Bng LDT c dnh ring cho cc m lnh, d liu, ngn xp,ca tng nhim v, chng trnh ng dng. Mi nhim v c mt bng b m t LDT ring ca n v do chng khng th truy nhp c vng nh ca nhau. Nh vy c nhiu bng LDT v mi bng LDT c xc nh bng mt b m t on LDT trong bng GDT.B m t on LDT cha a ch c s v di on LDT.Thng tin ny ca nhim v ang thc hin cng c cha trong thanh ghi h thng LDTR (thanh ghi bng cc b m t cc b).mi LDT c th cha cc b m t on lnh, on s liu, on ngn xp v cc ca giao dch kiu CALL. Mt nhim v ch c th thm nhp vo on m b m t ca n c cha trong bng LDT ang dng hay GDT. Nh vy, cc bng GDT v LDT cho php cch ly gia cc on nh thuc tng nhim v, nhng ng thi cng c th phn chia nhim v cho tng d liu chung cho tng nhim v.Bng IDT c dng m t a ch ca 256 ngt trong ch bo v ca b s l thay cho bng vcto ngt trong ch d thc thng thng.a ch c s v di on c cha trong thanh ghi h thng IDTR ( thanh ghi bng m t ngt).

Hnh m t mi lin h gia cc thanh ghi GDTR, LDTR v cc bng GDT, LDT.Cc lnh LGDT, LLDT v LIDT np a ch c s v di ca cc bng GDT, LDT v IDT vo cc thanh ghi tng ng.cc lnh SGDT v SIDT cp gi cc gi tr ca a ch c s v di ca cc thanh ghi vo b nh. Ch c h iu hnh thao tc vi cc thanh ghi trn, v vy cc lnh np v ct gi cc thanh ghi cn gi l cc lnh c quyn.cc lnh LMSW (np t trng thi my), LTR (np phn chn ca thanh ghi TR), CLTS ( xa bt chuyn nhim v TS), HALT ( dng hot ng ca b vi s l) cng thc v lnh c quyn.Ring lnh LLDT c dng np thanh ghi LDTRR c th c chy ch bi cc chng trnh ang chy mc c quyn cao nht.do tr khi mt nhim v ang hot ng mc c quyn cao nht, cn th n khng th thm nhp bng b m t cc b ca nhim v khc c. s chuyn nhim v thng c iu khin bi phn li ca h iu hnh, phn ny hot ng mc u tin cao nht.3.8.3 Cc b m t v b chn on nh3.8.3.1 Cc b m t on: mi on nh c cc thng s c chng cho n c lu tr trong mt vng nh 8 byte gi l b m t on c dng tng qut gm cc trng 32 bt a ch c s, 20 bt di on v trng thuc tnh ca cc loi nh sau: di on: gm 20 bt biu th cho di theo 2 cch ty thuc vo gi tr ca bt G. Nu G=0, di on nm gia 1 byte v 220 = 1 Mbyte tnh theo n v byte. Nu G=1, di on ngm gia 4 byte ti 232= 4 Gbyte tnh theo n v 4 Kbyte = 1 trang. Nu chng trnh c nh thm nhp vng nh ngoi gi hn di ny th s xy ra ngoi l. a ch c s on: gm 32 bt xc nh a ch thp nht ca byte nh trong on nm trong khng gian a ch tuyn tnh 4 Gbyte. Cc mc c quyn DPL: c dng kim tra quyn thm nhp tng ng vi mc c quyn ca nhim v y. nh vy trng di 2 bt ny c 4 gi tr t 002 n 112. TYPE: xc nh dng ca on hoc ca giao dch, xc nh kiu truy nhp v hng dng n ca on. D: xc nh chiu di ca ton hng. nu DB=1, a ch ton hng s di 32 bt. Nu DB=0, i ch ton hng di 16 bt. P: cho php xc nh on c tn ti trong b nh thc hay khng. Nu P =1, on c trong b nh vt l. Nu P = 0, on khng tn ti v mt ngoi l s xy ra. S: cc nh loi m t. nu DT=1, l loi b m t on gi liu, nu DT=0 l b m t on h thng. Cc bt cn li r, vs l d tr cho ngi dng hoc cho h iu hnh. Ging 80286, vi x l 80386 cng c 4 loi b m t on: B m t on s liu: tng t nh dng tng qut, ch c byte quyn thm nhp c gi tr ring nh sau: Bit S=1 phn bit vi on h thng. Bit E=1 phn bit vi on lnh, ED ch chiu pht trin ca s liu. nu ED=1, thng ch on ngn xp. nu ED=0, ch on s liu thng thng. W=0, on s liu ch c c. W=1, c th c c v vit. B m t on lnh: so vi on tng qut c mt s im khc sau: S=1. E=1. C=1, ch bng chng trnh c mc c quyn(PL>=DPL) th c th gi on lnh c b m t ny. R=0, on lnh khng c php c, R=1, on lnh c th c. B m t on h thng: m t cc thng tin v cc bng ca h iu hnh, v cc nhim v v v cc ca giao dch. Trng bit TYPE trong dng tng qut c xc nh nh sau:Kiunh nghaKiunh ngha

00000Khng dng81000Khng dng

10001on TSS ca 286 sn sng91001on TSS 386 sn sng

20010LDT101010D tr

30011on TSS ca 286 bn111011on TSS 386 bn

40100Ca giao dch CALL ca 286121100Ca giao dch CALL 386

50101Ca giao dch nhim v131101D tr

60110Ca giao dch ngt 286141110Ca giao dch ngt 386

70111Ca giao dch by 286151111Ca giao dch by 386

- B m t bng LDT(s=0, TYPE=2) cha cc thng tin v bng cc b m t cc b LDT. Mi nhim v c mt bng LDT. V lnh np thanh ghi LDTR ch c php mc c quyn 0 nn cc bt DPL ca b m t ca LDT khng c tc dng. b m t ca LDT ch c cha trong bng cc b m t ton cc GDT.- B m t TSS(S=0, TYPE =1, 3, 9, B): on trng thi nhim v ca TSS cha cc trng thi ca mt nhim v. b m t TSS cho thng tin v v tr, di v mc c quyn ca TSS. Cc bit TYPE cho bit TSS sn sng hay bn v TSS thuc 80286 hay 80386. Thanh ghi TR cha b chn tr ti TSS ang chy.-Cc ca giao dch(S=0, TYPE=4 n 7, C, F): cc ca giao dch dng diu khin vic thm nhp ti cc im vo ca mt on lnh. C 4 loi ca giao dch: ca giao dch kiu CALL, ca giao dch kiu ngt, ca giao dch kiu by v ca giao dch nhim v. cc ca giao dch cung cp phng tin cho vic chuyn giao iu khin mt cch gin tip gia chng trnh ngun v chng trnh ch. S chuyn giao ny cho php vi x l thc hin kim tra vic bo v mt cch t ng. n cng cho php ngi thit k h thng kim sot cc im vo ca h iu hnh. Dng tng qut ca b giao dch nh sau:+Ca giao dch kiu CALL thng dng chuyn iu khin chng trnh ti mc c quyn cao hn.B m t ca CALL c 3 trng thm nhp on ,b chn tr ti b m t on lnh ch v offset xc nh v tr trong on nh . Trong b m t cng cha 5 bit b m t cho bit s thng s cn sao t ngn xp ca chng trnh gi sang chng trnh c gi. ch c b m t CALL mi c b m t.+ Ca giao dch kiu ngt v kiu by cung cp b chn tr ti b m t lnh x l ngt v offset xc nh v tr bn trong ca on lnh . S khc nhau gia ca giao dch kiu ngt v kiu by l ch: ca kiu ngt cho php xa bit cho kiu ngt IF trong thanh ghi CF cn kiu by th khng.+ Ca giao dch nhimv c s dng khi c thay i nhim v. v ca giao dch nhim v ch quy chiu dn bng TSS nn ch c b chn tc dng, cn offset khng dng. B chn tr ti b m t TSS.Byte quyn thm nhp ca c 4 loi ca giao dch l ging nhau.3.8.3.2 B chn on l ni dung cha trong phn h 16 bit ca thanh ghi on c np bi chng trnh. Phn kn 64 bit c ni dung c vi x l t ng sao chp t b m t on sang gm 32 bit a ch c s, 20 bit di on v 12 bit quyn thm nhp.Ging nh trong 80286, 16 bit ca b chn c chia thnh 3 trng nh sau:Trng mc c quyn: gm 2 bit RPL vi 4 mc c quyn t 0 n 3 ca on nh.Trng chn bng cc b m t TI, nu TI=0 b m t nm trong bng GDT, nu TI=1 b m t nm bng LDT.Trng ch s(INDEX) gm 13 bit tr ti mt b m t on trong GDT hoc LDT. Tc l cng c th c ti chng y cc on nh vi cc a ch c s on 32 bit khc nhau. a hcir mt nh trong on s l tng ca a ch c s 32 bit ny v a ch lch offset 32 bit do chng trnh cung cp. do mc d khng gian nh vt l ca 80386 ch c 232=4 Gbyte nhng khng gian nh o c th ln ti 214x232=64 tetrabyte. T hp ca cc a ch c s on v lch bn trong cc on to nn thang a ch tuyn tnh trong on, c ngha rng ta c th tm thy cc a ch ln hn trong cc vng cao hn ca b nh.3.8.3.3 Bo v b nh -Cc quy tc v mc c quyn: nu chng trnh ang chy tm cch truy nhp mt on hay ca, b x l s so snh DPL vi CPL kim tra quyn truy nhp vo mt on. thng gi tr ca CPL bng gi tr mc c quyn ca on m lnh lu tr chng trnh ang chy. chng trnh ang chy c th thm nhp t do vo cc on lnh v on d liu c cng mc c quyn vi chng trnh. Khi iu khin vt ra khi mc c quyn ca chng trnh th phi tun theo cc quy tc v cc mc c quyn nh sau:- s liu lu tr trong on nh vi mc c quyn P no ch c th c thm nhp bng cc lnh c th thm nhp mc c quyn, t nht cng phi bng P. nu CPL l mc c quyn ca on lnh ang chy cn DPL l mc c quyn ca on lnh ang chy cn DPL l mc c quyn ca on d liu th iu kin thm nhp l:CPL=DPL

3.8.4 Ch bo v phn trang b nh3.8.4.1 Th mc trang, bng trang v trangTrong phng php ny, khng gian a ch o c tch ra thnh nhiu trang c kch thc bng nhau.Thng kch thc trang bng ly tha ca 2.VD 212= 4KB. Khng gian a ch vt l c tch thnh nhiu mng theo cch tng t, mi mnh c kch thc bng kch thc trang sao cho mi mng ca b nh chnh c kh nng lu gi ng mt trang. Khi mt nhim v yu cu truy cp mt a ch logic, b x l chuyn a ch logic ny thnh a ch tuyn tnh v trong ch phn on a ch ny cng chnh l a ch vt l.Nu trang cha a ch tuyn tnh khng tn ti trong b nh vt l th mt ngoi l s xy ra. Nu ch trang c php, b x l s chuyn dn a ch tuyn tnh sang a ch vt l tng ng vi cc trang. Thng tin m b x l dng nh x a ch tuyn tnh vo khng gian a ch vt l c lu tr vo cc vng nh gi l th mc trang v bng cc trang.Th mc trang (page directory) c 210= 1024 im vo 32-bit (4 bytes).Mi im vo tr ti mt trong 1024 bng trang. Nh vy th mc trang di 4KB. C mt thanh ghi iu khin c bit 32-bit CR3 cha a ch c s ca th mc trang. Ch c 20 bit cao ca a ch c s c ghi trong CR3 cn 12 bit thp c mc nh bng khng v a ch th mc trang phi c phn theo n v nh nht ca trang l 4KB.Ni dung ca mi im vo th mc trang nh sau.31 1211 10 9876543210

20bit a ch c s bng trangOSGPS0APCDPWTU/SR/WP

Bng cc trang (page table) cng c 210=1024 im vo 32-bit (4 byte).Mi im vo tr ti mt trong 1024 trang (cn gi l khung trang).Nh vy bng cc trang cng di 4KB. Ni dung ca mi im vo bng trang nh sau.31 1211 10 9876543210

20 bit a ch c s trangOSG0DAPCDPWTU/SR/WP

3.8.4.2 Tnh a ch vt l trong ch trangNu ch trang c php th 32 bit a ch tuyn tnh nhn c khi phn on s c dng xc nh a ch vt l ca cc byte nh trong cc trang.Nh trn ni, a ch c s ca th mc trang ny c gi trong thanh ghi iu khin CR3. Thanh ghi ny c gi l thanh ghi c s th mc trang PDBR (page directory base register) v cn c np khi khi ng my tnh. Ni dung ca n c th c thay i t ng khi thay i nhim v hay bng lnh MOV 32 bit a ch tuyn tnh lc ny c phn thnh 3 phn.

10 bit cao nht trong trng DIR l mt trong 1024 im vo ca th mc trang, mi im vo ny cho php tr ti mt trong 1024 bng trang.10 bit tip theo trong trng TABLE l mt trong 1024 im vo, mi im vo tr ti a ch ca mt trong 1024 trang thuc bng.12 bit cn li trong trng OFFSET cha a ch lnh ca nh cn truy nhp trong s 4KB ca mt trang. Cc bit ny cng vi a ch c s t mt im vo bng trang to ra a ch vt l cn truy xut b nh.Nh vy dung lng cc i ca b nh trong cu trc ny l:1024 bng trang x 1024 trang/mt bng trang x 4KB/trang= 4GB.3.8.4.3 Vai tr ca h iu hnh trong qun l trang.B x l thc hin qu trnh chuyn ha a ch trang gim bt gnh nng cho h iu hnh.H iu hnh (HH) c trch nhim np cc gi tr khi u vo bng cc trang v x l li ca trang.H iu hnh cng lm cho TBL mt hiu lc, khi c bt c s thay i no xy ra bt c im vo no ca bng cc trang.HH phi np li thanh ghi CR3 lm c TBL c sp xp li.Thit lp cc a ch trong trang c khi u bng vic np thanh ghi CR3 a ch ca th mc trang v cp pht khng gian nh cho cc th mc v bng cc trang. Trch nhim chnh ca h iu hnh l thc hin cc thut ton hon i gia b nh v a t v x l cc li v trang.H iu hnh m bo thng tin trong b m chuyn ha ring (TBL) trng hp vi thng tin trong bng cc trang. Bt c khi no nu h iu hnh xa bit P trong im vo ca bng cc trang (P=0) u phi sp xp li TBL. H iu hnh cng c th lu tr trong CR3 mt phn ca TSS cung cp cho mt nhim v hay mt nhm nhim v mt tp bng cc trang ring.Cui cng, c th so snh 2 cch phn on v phn trang nh bng di.

So snh s phn on v phn trang.Phn onPhn trang

Ngi lp trnh c cn bit k thut ny ang c s dng hay khng?CKhng

C bao nhiu khng gian a ch tuyn tnh?Nhiu 1

Khng gian a ch tng cng c th vt qu kch thc b nh vt l?CC

Cc th tc v d liu c th c phn bit v c bo v ring r?CKhng

Ti sao k thut ny c pht trin? cho php cc d liu c chia ra thnh nhiu khng gian a ch logic c lp v c th bo v c. c mt khng gian a ch tuyn tnh ln m khng cn phi mua nhiu b nh vt l.

3.9 Ch 8086 oMt kh khn chnh l khi thit k 386 l lm th no va nng cao kh nng ca 386 li va tng thch vi cc phn mn 8088/86 xy dng trn c s MS DOS ch bo v. gii quyt vn ny ,ngi ta b cho 80386 . ch o 8086 ,386 phn chia b nh thnh tng phn 1Mb ,mi phn c gn vi nhim v .Tng nhim v c chy nu l mt chng trnh 8086 ca b vi x l 386 cho php bt c chng trnh no c vit cho DOS u chy c khng phi thay i ca tng nhim v m nhim v c ring 1 Mb b nh .iu c ngha l ch o 8086 ,386 s dng khi nim SEG:OFFSET b vi x l 8086/386. C hai h iu hnh , MS WINDOWS 3x v IBM OS /2 2.0 u s dng ch o 8086 ca 80386 .Cc h iu hnh s dng ch o 8086 ca 386 chy nhiu chng trnh c vit cho 8088/86 .im khc nhau gia chng l vi MS WINDOWS ,ti mt thi im ch c mt nhim v c kch hot v tt c cc nhim v khc ngh ,cn OS /2 2.0 mi nhim v u chim mt phn thi gian ca CPU v nhiu nhim v c th c kch hot ng thi .V d , trong khi ang thc hin x l vn bn th FAX/Modem vn nhn v gi d liu , mt chng trnh bng tnh nh LOTUS 123 vn tin hnh mt s php ton ,ng thi a mn cng ang c nh dng .Tt nhin, do ch c mt b vi x l nn cng vic ca h iu hnh OS /2 2.0 ly mt phn thi gian ca CPU cho tng nhin v theo phng thc quay vng .Nu c qu nhiu nhim v v tt c u cng c kch hot th s lm cc chng trnh chy chm li bi v mi nhim v c c t thi gian ca CPU hn .Tt nhin c gii php khc phc vic chng trnh b chy chm l s dng cc CPU hn .Tt nhin c gii php khc phc chng trnh b chy chm l s dng cc CPU c tc cao 60 80 MHz nh Pentium chng hn . Ch rng ,trong khi OS/2 2.0 s dng kh nng a nhim c lp th Windows 3.x li s dng kh nng a nhim phi hp , hai hoc nhiu ng dng phi hp vi tng ng dng khc ng chy tn dng CPU xen k . Nu c mt ng dng b b qua th c th gy ra ton h thng b xung t. ch a nhim ring r ,mi nhim v c th c chng trnh khc ngt ring tai mt im bt k .Nu mt nhim v b mt chng trnh khc ngt th trang thai hin hnh s c h iu hnh lu li v n li tip tc c phc v sau khi nhim v mi c trao quyn s dng cho CPU.

80386 chuyn ti ch 8086 o chy trong mt khong thi gian dnh cho chng trnh loi 8086 v ri d dng quay v ch bo v chy trong khong thi gian dnh cho nhim v hot ng trong ch bo v. iu ny c ngha rng mt vi ngi dng trong h thng a ngi dng c th chy cc chng trnh trong ch bo v trng khi cc ngi dng khc c th ang chy cc chng trnh DOS trong ch thc. Khi 386 ang chy trong ch bo v thc hin chuyn nhim v, n kim tra bit VM trong thanh ghi c. Nu bit ny c t ln 1, 386 s nhy vo ch 8086 o thc thi nhim v mi.Di y tm tt tin trnh chuyn sang ch 8086 o trong cc trng hp: Chuyn nhim v v t c VM= 1 cu EFLAGS c lu tr trong TSS. Chuyn nhim v c thc hin theo 2 cch: dng lnh CALL hay JMP, dng lnh IRET khi c NT ca EFLAGS lu tr trong TSS bng 1. Quay li t mt chng trnh x l ngt hay ngoi l v t c VM= 13.10 Ch thc ca 80386 (real mode)Trc ht chng ta s xem xt b vi x l Inteln 80186 v cc c im ca chng theo kha cnh lp trnh ch thc.3.11 Cc thay i chnh 80386.B vi x l 80386 khi u cho mt khuynh hng mi c h 80x86. B vi x l ny tng thch vi 8088/86 v 286, song cu trc bn trong c nhiu thay i. Di y s nu mt s nt chnh ca 80386.1. Bus d liu tang t 16 bit ln 32 bit c bn trong v bn ngoi.2. Tt c cc thanh ghi u m rng ti 32 bit v th 80386 l b vi x l 32 bit.3. Bus a ch c tng ln 32 bit do c kh nng nng b nh vt l nn 4GB.4. B sung c ch b nh o phn trang. Nh vy 386 va c ch phn trang va c ch phn on.5. B sung thm ch a ch mi gi l ch s t l (scale index).6. Nhiu lnh thao tc bit mi c b sung. Cc lnh ny lm vic c c ch thc v ch bo v.7. 386 c th chuyn t ch bo v sang ch thc bng phn mm. y l mt pht trin so vi 286 (286 phi thc hin bng phn cng dng RESET). gim gi thnh thit k board mch, hng Intel sn xut b vi x l 80386SX c bus d liu ngoi 16 bit, bus ni b 32 bit v tng thch 100% vi 80386. V tc 386SX chm hn so vi 386 bi v n cn n 2 chu trnh nh (mi chu trnh cn 2 nhp ng h) nh a ch 32 bit ch khng phi l mt chu trnh nh nh trong trng hp 80386. ch thc, 80386 s dng cc chn a ch A19-A0 v c th truy nhp ti a 1MB. Tuy nhin, trong ch bo v 386 c th truy nhp ti 4GB b nh thng qua bus a ch 32bit.3.12 Cc thanh ghi a nng lm con tr.Mt thay i khc 80386 l s dng cc thanh ghi a nng nh EAX, ECX, EDX lm con tr. 8088/86/286 ch s dng cc thanh ghi BX, SI v DI lm con tr ch cc on d liu. Nhng bt u t 386, tt c cc thanh ghi a nng 32 bit u c th s dng lm con tr tr n on d liu. Ta xem cc lnh hp l v khng hp l sau.MOV BX, WORD PTR[EAX];ngMOV BX, WORD PTR[AX];sai, AX khng lm con tr cMOV EAX, DWORD PTR[ECX];ngMOV EBX, DWORD PTR[CX];sai, CX khng lm con tr c.386 cng cho php cng thm di vo cc thanh ghi 32 bit lm con tr.MOV AL, [ECX+100];ng.Tt nhin 386 c th s dng tt c cc ch a ch ca 8086/286.Bng di y gii thiu mt s ch a ch c th p dng c 386.Bng: Cc ch a ch ca 80386.Ch a chTon hngon ngm nh

Thanh ghi (Register)Thanh ghi (Register)None

Tc th (Immediate)D liu (Data)None

Trc tip (Direct) di ([OFFSET])DS

Thanh ghi gin tip (Register indirect)[BX][SI][DI][EAX][EBX][ECX][EDX][ESI][EDI]DSDSDSDSDSDSDSDSDS

Quan h c s(Based relative)[BX]+disp[BP]+disp[EAX]+disp[EBX]+disp[ECX]+disp[EDX]+disp[EBP]+dispDSSSDSDSDSDSSS

Quan h ch s (Indexed relative)[DI]+disp[SI]+disp[EDI]+disp[ESI]+dispDSDSDSDS

Quan h ch s c s (Based indexed relative)[R1][R2]+disp[R1] v [R2] l bt c ton hng no nu trnNu s dng BP th on l SS, vi cc thanh ghi khc th s dng on DS.

Chng 4. Kin trc Pentium4.1 Thanh ghi (registers)Cc kin trc Intel ch nh mt tp hp khng c cc thanh ghi p ng hu ht cc lp trnh vin assembly. Tuy nhin, cc b vi x l c s lng cc thanh ghi lm bt c iu g l cn thit.p ng hu ht mc ch s dng, chng ta dng32-bit 16-bit 8-bit 8-bit(high part of 16) (low part of 16)

EAX AX AH AL EBX BX BH BL ECX CX CH CL EDX DX DH DL

v

EBP BP ESI SI EDI DI ESP SPS dng cc thanh ghi: Nh l cc ton hng, ch cn dng tn ca thanh ghi.EBP l mt con tr khung hnh, ESP l mt con tr ngn xp.Cc thanh ghi khc.Nhiu bit(s) c s dng kim sot hnh ng ca b vi x l v thit lp trng thi ca cc thanh ghi gi l EFLAGS. Thanh ghi ny cha cc m iu kin.OF C chnSF C du.ZF Zero flagPF C chn lCF C nhCc thit lp c c kim tra trong nhng cu trc iu khin c iu kin. Nhiu ch th thit lp 1 hoc nhiu c (flags).Vic s dng thanh ghi EFLAGS c ng (ch khng phi r rang) trong ch th lnh.4.2 Truy nhp b nh (Accessing Memory)Hin c 2 m hnh b nh trong kin trc Pentium.(Trn thc t n l 486 v nhiu m hnh gn y h tr 2 m hnh).Trong c 2 m hnh, b nh c truy cp bng cch s dng mt a ch. l cch m cc a ch c hnh thnh (trong cc b vi x l) khc nhau trong 2 m hnh.M hnh b nh flat.M hnh b nh m tt c mi ngi u s dng.M hnh phn on nh (segmented memory model). Cc phn khc nhau ca mt chng trnh c gi nh l ca chnh n, ci t sang cc phn ca b nh. Mt a ch c hnh thnh t 2 phn: 1 v tr phn on v 1 offset trong phn on (segment).Lu mi thnh phn ny c th l ngn hn (c cha cc bits t hn) so vi mt a ch ton b. V iu ny Intel chn hnh thc m hnh b nh u tin cho cc b vi x l chip n. C cc phn on (segments) cho:+ code+ data+ stack+ nhng th khc4.3 Kin trc Pentium Pro v sau Ch th gii m (instruction decode) dch m my (machine code) vo RISC OPS (ging nh ch th gii m MIPS).Mt n v thc thi (execution unit) chy RISC OPS:+ Kh nng tng thch ngc (Backward compatiblity).-Complex gii m (Complex decoding).

Ti liu tham kho1. Intel 80386 Programmers Reference Manual.2. Introduction to 80386 assembly language.3. Principles of Computer Hardware - Alan Clements4. Computer Organization and Assembly Programming for IBM PC and compatibles Michael Thorne5. Computer architecture: a quantitative approach John L. Hennessy, David A. Patterson, Andrea C. Arpaci-Dusseau.6. Computer architecture and implementation Harvey G. Cragon7. Computer Architecture & Organization D.A.Godse8. Fundamentals of digital logic and microcomputer design Mohamed Rafiquzzaman.9. http://pages.cs.wisc.edu/~cs354-1/karen.notes/Pentium.html

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