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GOG-SOFT [email protected]

Tuyt i. (ca mt gi tr), thc v khng i. V d, absolute address (a ch tuyt i) l mt vtr trong b nh v an absolute cell reference (tham chiu tuyt i) l mt c nh n trongmt mn hnh bn tnh. Phn ngha ca absolute (tuyt i) l relative (lin quan).

Th tng tc. Kiu bn m rng lm cho mt my tnh chy nhanh hn. N thng cha mt nv x l trung ng b sung.

Thi gian truy cp. Hay reaction time (thi gian hot ng), thi gian cho my tnh sau mt lchc cho, c t b nh hay vit ln b nh.

Thanh ghi tm thi: mt b ng k c bit hay v tr b nh trong mt n v s hc v logictrong b x l my tnh. N c s dng gi kt qu ca mt s tnh ton tm thi hay lud liu ang c chuyn.

B ghp m thanh. Thit b cho php d liu my tnh c tuyn v nhn thng tin qua mt inthoi c nh (in thoi con) thng thng, my in thoi ny gn trn b ghp to s ni.Mt loa nh trong thit b c s dng chuyn d liu tn hiu dng k thut s ca my tnhthnh tn hiu m thanh m phng sau c in thoi con NHN. IN THOI NHN,MT B GHP M THANH TH hai hay mt mdem chuyn cc tn hiu m thanh tr li thnhd liu k thut s cho tn hiu vo my tnh. Khng ging nh mem, mt ghp m thanh khngyu cu s ni trc tip ti h thng in thoi.

H thng m do h Adoble pht trin cho cc ng dng in n (xut bn) in t. M Acrobat cth c pht ra trc tip t tp tin Post Script.

T vit tt t ch u, t c to ra t cc ch u v/hay vn ca cc t khc, c dng nhmt ch vit tt pht m c. V d, RAM (random access memory: b nh truy cp ngu nhin)v FORTRAN (formula translation: phin dch cng thc). Ngc li, cc ch u to thnh mtch vit tt c pht m tch ring mi ch, v d, ALU (arithmetic and logic unit: n v s hcv logic).

http://gog.soft.googlepages.com

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Ngn ng lp trnh my tnh mc cao, do US Department of Defense (B quc phng M) phttrin v gi bn quyn, c thit k s dng trong cc tnh hung m mt my tnh trc tipiu khin mt qu trnh hay my, nh mt my bay qun i. Phi mt hn 5 nm chuyn

mn ha ngn ng ny v n ch tr nn tin dng ph bin vo cui nhng nm 1980. N ct theo tn nh ton hc Anh Ada Augusta Byron.

Ch vit tt ca Analogue to digital converter: b chuyn i k thut m phng thnh k thut s.

B cng: mch in t trong mt my vi tnh hay my tnh ton thc hin qu trnh cng hai chs nh phn. Mt b cng ring cn thit cho vic cng mi cp bit nh phn. Cc mch nh th l

nhng thnh phn thit yu ca mt n v thut ton v logic ca my tnh (ALU).

A CH: S CH TH MT V TR C BIT CA B NH MY TNH. MI A CH, MTMU N CA D LIU C TH C LU. I VI MY VI tnh, a ch ny c tng lithnh 1 byte ( biu th mt k t n, nh l mt ch hay s).

THANH GP A CH: NG DN IN T HAY l thanh gp c dng chn hnh trnh

cho bt c d liu ring no nh khi n di chuyn t phn ny n phn khc ca my tnh.

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Ch vit tt artificial intelligence: tr thng minh nhn to.

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(t ch u ca algorithmic language: ngn ng thut ton) ngn ng lp trnh mc cao trcy, c pht trin vo nhng nm 50 v 60 cho cc ng dng khoahc. Mt ngn ng mcdch tng qut, ALGOL l thch hp nht i vi cng vic ton hc v c mt kiu i s. D

khng cn thng dng na nhng n nh hng ln n cc ngn ng ngy nay nh ADA vPASCAL.

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Thut ton: trnh t hay chui cc bc c dng gii quyt mt vn . Trong khoa hc mytnh, trnh t logic cc thao tc c thc hin bi mt chng trnh. Mt s dng l s biuth nhn thy c ca mt thut ton.

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C BIT DNH CANH PHI: NH HNG C nhn thy trn mn hnh hay tn hiu ra my


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in, khi cc ng cong mn xut hin cu thnh cc bc do phn gii khng cao.Chng bit hiu l mt k thut phn mm gim nh hng ny bng cch dng cc thang omu xm.

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Mt th mch RISC 64 bit c phng ra vo nm 1993 bi thit b k thut s (DEC). N cxem nh l mt cnh tranh vi th mchPentium ca Intel.

D liu ch s, d liu cu thnh cc ch ci v bt k ch s t 0 n 9. S phn loi ca dliu ty theo kiu k t c cha cho php h thng hiu lc my tnh kim tra chnh xc cad liu; mt my tnh c th c lp trnh loi b cc u vo cha cc k t sai. V d, tnca mt ngi c th c loi b nu n cha bt k d liu s v mt s ti khon ngn hngc loi b nu n cha bt k d liu ch ci. So vi s ng k xe th s cha d liu ch snhng khng c cc du chm cu.

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Ch vit tt ca arithmetic and logic unit (n v s hc v logic).

Vin tiu chun quc gia Hoa K. Vin t cc th tc chnh thc trong (gia cc lnh vc khc)my tnh v in t.

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Tng t, lin bin (ca mt s lng hay thit b) t l hay song song vi cc gi tr thay i lintc v so snh trc tip bng cch i chiu mt s lng m phng hay thit b thay i trong ccchui bc ring bit. V d, mt ng h m phng o thi gian bng cc phng tin ca mtchuyn ng lin tc bng tay xung quanh mt mt s ni mt ng h k thut s o thi gianvi mt hin th s thay i trong mt chui cc c ring bit.

My tnh m phng, my tnh tng t: my tnh c thc hin mch v x l d liu k thut(m phng) thay i lin tc. Cc my tnh k thut s m phng him hn nhiu so vi cc myk thut s v thng l cc my c mc ch c bit c xy dng vi mn hnh v iu khincc thit b khc.

B chuyn i k thut m phng thnh k thut s: mch in chuyn mt tn hiu k thut mphng thnh mt tn hiu k thut s. Mt mch nh th th chng trnh chuyn tn hiu tmt thit b k thut m phng thnh mt tn hiu k thut s cho vic nhp vo my tnh. V d,nhiu cm bin c thit k o cc gi tr vt l nh nhit v p sut, sinh ra mt tn hium phng di dng in th v c truyn qua mt ADC trc khi my tnh nhp v x l n.

Mt b chuyn i k thut s thnh k thut m phng (DAC) thc hin qu trnh ngc li.


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NG C PHN TCH. THIT B MY TNH C TH lp trnh c do nh ton hc ngi AnhCharles Baddage thit k nm 1833. N c da trn cc ng c khc nhau nhng chng ti t ng ha c qu trnh tnh ton. N gii thiu nhiu quan im v my tnh k thuts nhng do hn ch trong qu trnh sn xut, n khng c xy dng cho ti nm 1992 khi mtphin bn lm vic c gii thiu trong bo tng KHOA HC, LUN N.

Cng AND. Kiu cng logic.

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Vit tt ca American National Standards Institule. Vin Tiu Chun Quc gia Hoa K.

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Vit tt ca Applications Program Interface: Giao din Chng trnh ng dng.

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Cng ty my tnh Hoa K, nh sn xut loi my Macintosh.

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Chng trnh ng dng, chng trnh cng vic c thit k tin li cho ngi s dng nhmt h bng lng hay b x l t ng. Cch dng nhn bit cc chng trnh nh th, t iu khin my tnh hay gip tho chng vin mt b bin dch.

B chng trnh ng dng. B chng trnh v cc ti liu lin quan (nh s tay hng dn)c dng trong mt ng dng c bit.

Chng trnh ng dng. Chng trnh thnh lp thc hin mt cng tc cho s tin li cangi s dng my tnh - v d, tnh ton s tr lng hay x l t. Ngc li, mt chng trnhh thng thc hin nhiu cng tc lin quan ti hot ng v thc hin ca chnh my tnh.

Giao din chng trnh ng dng, trng tiu chun bao gm cc dng c, th tc v cc trnh tkhc trong cc chng trnh c th c vit. Mt API bo m rng tt c cc ng dng lph hp vi h iu hnh v c mt giao din s dng tng t.


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i s, gi tr trn mt hm s thc hin. V d, nu argument 16 c thc hin trn hm s''cn bc hai th a ra kt qu l 4.

N V THUT TON V LOGIC: PHN CA N V x l trung ng thc hin cc thao tcs hc c bn v logic trn d liu.

Chui: trong mt my tnh lp trnh, mt chui cc gi tr c th c tham kho ti bi mt tnbin i n. Cc gi tr ring c phn bin bng cch dng mt hay nhiu ch s di dngvi mi tn bin i. V d, xem danh sch v nhit cao nht mi ngy.

Ngy 1

22

Ngy 2

23

Ngy 3

19

Ngy 4

21

Chui ny c th c xem vi tn bin i n temp. Cc yu t ring ca chui sau s cxc nh vi cc ch s di dng. V d, phn t chui temp1 s lu gi tr 22, 'temp 3 s lu gitr 19.

Mt chui c th s dng nhiu hn mt ch s di dng. V d, xem danh sch sau y ch spanh sa (n v o lng bng 0,57 1 Anh v 0,47 1 M) c phn ra trong bn nh.

Nh 1

Nh 2

Nh 3

Nh 4

Ngy 1


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2

2

3

1

Ngy 2

2

1

2

1

Ngy 33

2

0

1

Ngy 4

2

1

2

1

Ngy 5

4

1

2

2

Ngy 6

4

5

4

4

Nu chui ny c cho tn bin i pint (panh) th cc yu t ca n s c xc nh vi hai ch

s: mt i vi nh v mt i vi ngy trong tun. Do , phn t chui pints (,2,6) s lu gi tr


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5, pints (3,3) lu gi tr 0.

Cc chui th hu dng v chng ch cho php cc tho chng vit cc trnh t tng qut cth x l cc danh sch d liu di. V d, nu mi gi c lu trong mt chng trnh k tons dng mt tn bin i khc nhau th cc lnh chng trnh phn tch s c yu cu x l

mi gi. Tuy nhin, nu tt c cc gi c lu trong mt chui th mt trnh t tng qut c thc vit x l, ni nh gi (J) v bnh cch cho php J ly cc gi tr khc nhau, sau cth x l bt c cc d liu ring no.

Tr thng minh nhn to. Mt ngnh khoa hc lin quan ti vic to cc chng trnh my tnh cth thc hin cc hot ng so snh vi nhng hot ng ca mt con ngi thng minh. Nghincu AI hin thi bao trm cc lnh vc nh lp k hoch (cho cch x rb), hiu bit ngn ng,nhn bit mu, biu th kin thc.

Cc chng trnh AI trc kia c pht trin nm 1960 t c s m phng tr thng minh

con ngi hay c gip k thut gii quyt vn tng qut. By gi ngi ta ngh rngcch c x thng minh ty thuc nhiu vo kin thc mt h thng c c nh trn ngun l lca n. Do , s nhn mnh hin c trong cc h thng da trn kin thc.

(t ch u ca American Standard Code for Information Interchange) h lp m trong cc sc quy nh cho cc ch, ch s v cc biu tng chm cu. D cc my tnh lm vic trongm s nh phn, cc s ASCII thng c nh nh cc s thp phn hay thp lc phn, 32 mu c dng cho cc chc nng iu khin nh tr hp bng v xa ngc. Ni chnh xc,ASCII l mt m nh phn 7 bit cho php 128 k t khc nhau c biu th nhng mt bit th tm

th thng c dng cung cp tnh chn l hay cho php i vi cc k t ph. H thngny c dng rng ri i vi vic lu vn bn.

Ngn ng chng trnh hp ng, ngn ng lp trnh my tnh mc thp lin quan mt thit ticc m bn trong mt my tnh. N gm ch yu mt b cc chui ngn vi ch (thut nh) cb dch hp ng dch thnh m my cho n v x l trung ng ca my tnh lm theo mtcch trc tip. Trong ngn ng chng trnh hp ng, JMP c ngha l nhy (Jump) v LDA cngha l Load accumulation (b tr ti) m chng trnh hp ng c cc tho chng vin sdng vit cc chng trnh rt nhanh v hiu qu.

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Khng ng b (d b). Khng theo qui lut hay khng ng b. Thng c cung cp trong struyn thng truyn d liu khng qtho qui lut so vi mt dng n nh. S thng tin khngng b dng cc bit bt u v bit kt thc ch s bt u v s kt thc mi mu d liu.

Vt kim tra. bn ghi li cc hot ng my tnh ch nhng g c thc hin v ai thc hin n(nu thng tin ny c sn). Thut ng ny c ly trong k ton nhng cc vt kim tra (chuikim ton trong k ton ngy nay c dng rng ri kim tra nhiu kha cnh an ton my

tnh cng nh trong cc chng trnh k ton.


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File trong iu hnh MS-Dos bao gm cc lnh c thi hnh khi my tnh c khi ng, nc chy t ng vo lc ny.


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rng di tn. Trong my tnh v trong thng tin lin lc, khi nim ny xc nh tc chuynd liu, c o bng s bit mi giy.

Mc, chun

Php o hiu qu ca mt mu thit b hay phn mm, thng bao gm mt chng trnh tiuchun hay mt b chng trnh. Cc mc c th ch ra xem mt my tnh c mnh thc hinmt tc v c bit no hay khng v cho php so snh cc my vi nhau. Tuy nhin, chngch o cc thng s c bit v c th khng a ra mt hng dn chnh xc tng tc ccng dng thc t. Mc o bao gm Whetstones, Dhrystones, TPC v SPECmarks. SPECmarksda trn 10 chng trnh c chp nhn bi h thng thc hin nh ga kt hp cho cc trmlm vic chun. Mc TCP-B ca hi ng thc hin x l giao dch c s dng th c s dliu v h thng trc tuyn trong phm vi ngn hng.

Bn th nghim trc pht hnh

Phin bn trc khi tung ra chnh thc ca mt phn mm hay chng trnh ng dng, thngc phn phi ti mt s hn ch cc chuyn vin s dng (v thng l cc nh ph bnh). Sphn phi ca phin bn ny cho php ngi s dng kim tra v phn hi li ngi pht trin bt c bin i cn thit no cng c th c thc hin trc khi pht hnh.

S bit

L mng bit c s dng m t mt t chc d liu. Cc s bit c dng lu cc hnhnh ha bng cch dng gia tr 1 biu th en (hay mu) v gi tr 0 biu th trng. Tuynhin ha dng s bit khng c s dng cho cc hnh nh yu cu o c (trong trnghp ny ngi ta s dng ha vc t lu di dng cng thc hnh hc). Cc s bit c thc s dng lu tr kiu ch hay phng ch nhng mi c hay kiu ch i hi phi c mtbt s bit ring. Mt b phng kiu vc t c th c gi lm d liu mu v o c khi cnthit.

Cu ni

Thit b ni hai mng a phng tng t nhau. Cc cu ni l th tc c lp, chuyn d liutrong cc b gia hai mng m khng lm mt bt k thay i no.

Cu ch ng

Thit b kt ni cc mng t hp chc nng ca c hai thit b l cu ni v b ch ng. Cc cuch ng thng a ra hnh trnh c th theo v ni cu nhng th tc cn li.


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Thanh gp

NG DN IN T THNG QUA MT B VI X L my tnh lin lc vi cc thnhphn khc ca n hay vi cc thit b ngoi vi. V mt vt l, thanh gp l mt b cc ng songsong c th mang cc tn hiu k thut s . N c th c dng vt lt ng trn bng mch in mytnh (PCBs) hay ca mt cp bn ngoi hay s ni kt. Mt my tnh in hnh c ba thanh gpbn trong nm trn bn mch chnh ca n, mt thanh gp d liu (data bus) mang d liu giacc thnh phn my tnh, mt thanh gp a ch (address bus) chn cc th tc c lm theo bibt c mu d liu ring bit no i dc thanh gp d liu v mt thanh gp iu khin (controlbus) c dng quyt nh xem d liu c c hay ghi t thanh gp d liu. Mt thnh gpm rng (expansion bus) bn ngoi c dng cho vic ni b x l my tnh ti thit b ngoi vinh modem v my in.

B nh d liu, b nh bn ngoi n v x l trung ng dng lu cc chng trnh v olng khng c dng hin thi. B nh d tr phi khng d bay hi ngha l ni dung ca nphi khng c mt khi ngun cung cp ti my tnh khng c ni na.

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Sao chp d tr, cc file sao chp c chuyn ti cc phng tin khc, thng l ly ic, l a mm hay bng. Mc ch ca iu ny l c bn sao ca mt file m n c thc phc hi trong trng hp c d h hng trong h thng hay trn chnh file . cc file saochp cng c to bi nhiu ng dng (vi phn m rng l BAC hay BAK), do , mt phinbn l s c sn ca mt file gc trc khi n c bin i bi ng dng hin thi.

H thng sao chp: mt h thng my tnh sao chp m c th tip nhn hot ng ca my mytnh trong bin c ca s h hng thit b hay cho nhu cu bo tr. Cc h thng sao chp mrng sao chp d phng tng v h thng sao chp y .

M thanh: mu ca cc thanh v cc khong trng c th c c bng mt my tnh. Cc mthanh c s dng rng ri trong s bn l, phn phi cng nghip v cc th vin cng cng.Cc m ny c c bi mt thit b qut, my tnh xc nh m t cc rng ca cc thanh vkhong trng.

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( t vit tt ch u ca beginer's all purpose symbolic instruction code: m ch dn biu tng ttc mc ch ca ngi mi s dng), ngn ng lp trnh my tnh mc cao, c pht trinnm 1964, c thit k nguyn thy nhn s tin b ca cc h thng nhiu ngi s dng(c th c s dng bi nhiu ngi cng lc). Ngn ng ny d lin h hc v ph bin trongs nhng ngi s dng my vi tnh. N l phn c bn tip theo cho cc ngn ng mi nhVisual Basic.


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X l b, h thng x l d liu vi t hay khng c s can thip ca ngi vn hnh. Cc b dliu c chun b tin ti c x l trong qu trnh chy bnh thng (v d, mi ti). IUNY CHO PHP MY TNH S DNG C HIU QU V thch hp tt cho cc ng dng ca

mt kiu lp li nh mt bn lng cng ty.B x l tng phn vi my tnh tc ng xen k, trong d liu v cc lnh c nhp votrong khi chng trnh x l ang chy.

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N V O TC CHUYN D LIU. Nu mt tn hiu hiu th mt bit, sau mt baud biuth mt tc chuyn ca mt bit mi giy (bps).

M Baudot, m 5 bit c pht trin bi mt k s ngi Php Emil Baudot vo nhng nm 1870.N cn dng trong telex.

NG CONG BZIER, NG CONG NI MT CHUI im (hay nt) bng phng phpmn nht c th. Hnh dng ng cong MI NT C IU HNH BI BA IM IUKHIN. NG cong Bezier c s dng trong ha my tnh v CAD (computer aideddesign: my tnh gip thit k ).

M s nh phn, m s da trn h thng s nh phn, c dng biu th cc lnh ch dn vd liu trong tt c cc my tnh k thut s iu s dng trong hu ht cc my vi tnh, ch hoaA u th bi s nh phn 01000001

Do cc s nh phn ch dng cc ch s 0 v 1 nn chng c th c biu th bi bt c thit bno c th tn ti trong hai trng thi khc nhau. Trong mt my tnh k thut s, nhiu thit b haitrng thi khc nhau c dng lu hay chuyn cc m s nh phn v d nh - cc mch, cth hay khng th mang in th, a hay bng m cc phn ca n c th khng th c t hav cng tc (chuyn mch) c th m hay ng.

Cc my tnh k thut s c thit k theo cch ny bi hai l do. Th nht, to thit b haitrng thi th d v r hn nhiu so vi thit b tn ti nhiu hn hai trng thi. Th hai s truynthng gia cc thit b hai trng thi th rt ng tin cy v ch c hai tn hiu khc nhau, 0 hay 1(m hay tt cn c nhn bit.

H thng s nh phn, h thng s c s hai c dng trong my tnh v in t. Tt c cc snh phn c vit bng cch dng s kt hp ca cc ch s 0 hay 1.

S thp phn thng thng hay c s 10, cc s c th c xem nh c vit dc cc uct da trn s 10. V d, s thp phn 2,567 vit tt ca:

1.000 s

100s


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10s

1s

(103)(102)

(101)

(10)

2

5

6

7

Nh phn, hay c s 2, c s c vit di cc u ct da tn s 2. V d, s nh phn ca1101.

8s

4s

2s

1s

(23)

(22)

(21)

(20)

S nh phn 1101 do tng ng vi s thp phn 13 v (1x8) + (1x4) + (1x1) = 13

Tm h nh phn, k thut nhanh c dng tm bt c bn ghi no trong mt danh sch ccbn ghi c gi trong th t sp xp. My tnh c lp trnh so sch bn ghi c tm thyvi bn ghi gia trong DANH SCH TH T. IU NY ANG C THC HIN, my tnhloi b na danh sch trong bn ghi khng xut hin do gim s bn ghi tm kim xongti phn na, qu trnh ny c lp li cho ti khi bn yu cu c tm thy.

My tnh sinh hc, xut k thut i vi cc thit b my tnh da trn d tng trng ccphn t hu c phc tp ( phn t sinh hc) nh l cc cu t, c s l thuyt ca n l cc ,khi xy dng ca tt c vt th sng c cc h thng ha hc c th lu v trao i cc in t

v do hot ng nh cc cu t c in. N l ti hin thi c nghin cu lu di.


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(t ch u ca basic input/output system: h nhp xut c bn) phn ca h iu hnh iukhin nhp v xut. Thut ng ny cng c dng m t cc chng trnh c lu trongROM (v c gi l ROM Bios), m n chy t ng khi mt my tnh c bt ln cho php n

khi ng. BIOS khng b nh hng bi s nng cp ln h iu hnh c lu trn a.

Mch lt, hay mch in n gin bp bnh cn tn ti trong mt hay hai trng thi n nh cho tikhi n nhn mt xung (tn hiu logic 1) thng qua mt trong nhng u vo ca n, trong nchuyn hay ''flip trn trng thi khc. Do n l thit b hai trng thi nn n c th c s dng lu cc ch s nh phn v c s dng rng ri trong mch t hp.

Ch s nh phn, ch s nh phn n, hoc l 0 hoc l 1. Mt bit l n v nh nht ca d liuc lu trong my tnh, tt c cc d liu khc phi c m ha thnh mt mng ring bit.Mt byte biu th b nh my tnh y lu mt k t d liu n v thng cha 8 bit. Vd, trong h m ASCII c dng trong hu ht cc myvi tnh, th ch hoa A c lu trong mtbyte n ca b nh nh mt mng bit 01000001.

S bit ti a m mt my tnh c th x l thng thng vo mt lc c gi l mt t.

Phng c lp s bit, phng c gi trong b nh my tnh nh mt b s bit.

M BIT: THIT B NHP CA MY TNH, XEM BNG ha.

Khi; nhm h s c x l nh mt n v hon chnh cho vic chuyn i hay chuyn li bnh d tr. V d, nhiu a chuyn d liu trong khi 512 byte.

I S BOOLEAN, B QUI TC I S, C T TN THEO NH TON HC GEORGE

BOOLE, TRONG TRUE (NG) v False gm mt chui ton t AND (v), OR (hoc), Not(khng), NAND (NOTAND: khng, v), NOR (hoc khng) v XOR (exclusive OR: hoc loi tr)m n c th C DNG NH TN HIU NG (TRUE) V SAI (False) (xem bng tht)v l c s ca logic my tnh v gi tr tht c th c nhn bit trc tip bng cc bit.

I S BOOLEAN: CC TON T

Ton t

Ngha


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x AND y

Kt qu ng nu c hai x & y u ng, ngc li kt qu sai.

x OR y

Kt qu ng nu x hoc y ng, ngc li kt qu sai

x XOR y

Kt qu ng ch nu x v y khc bit, ngc li kt qu sai

NOT x

Kt qu ng nu x sai, kt qu sai nu x ng.

Khi ng (mi) hay qui trnh mi bt u my tnh. Hu ht cc my tnh c mt chng trnhmi nh, gn lin (BIOS) bt u t ng khi my tnh c bt ln - nhng cng tc ca n l

ch ti chng trnh ln hn mt cch nh nhng, thng t mt a m ngc li np v biu hnh. Trong my vi tnh, BIOS thng c gi trong b nh ROM thng tr v chngtrnh mi khi ng hot ng ca n mt cch n gin.

(vit tc ca bits per second: s bit mi giy) mt php o c dng xc nh tc truyn dliu.

My in phun bt kh, my in phun mc trong c nung nng ti im si n to mt bt kh u mt bec phun. Khi bt kh n, mc c chuyn ti giy.

B nh bot, thit b b nh da trn to ra cc bt nh trn mt b mt t tnh. Cc b nh?Bubble in hnh lu ti 4 megabit (4 triu bit) thng tin. Chng khng nhy v va p v s rungng, khng ging nh thit b b nh khc nh a nhng ging nh a t tnh, chng khngd bay hi v khng lm mt thng tin khi tt my tnh.


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Sp xp bot, k thut sp xp d liu. Nhng mc k cn c trao i lin tc cho ti khi d liuthnh mt trnh t.

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B m. Phn ca b nh c dng lu d liu mt cch tm thi. V d, mt chng trnhc th lu d liu trong mt b m my in cho ti khi my in sn sng in chng.

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Li trong mt chng trnh. N c th l li trong mt cu trc logic ca chng trnh hay mt lic php nh li chnh t. Mt vi bug lm cho mt chng trnh hng ngay tc khc, mt s khccn khng l ra, gy ra cc vn ch khi mt s kt hp ring bit ca cc chng c xy ra. Qutrnh tm v tr li i t mt chng trnh c gi l debugging.

Bng thng bo, trung tm lu tr ca cc tn hiu, thng c truy cp trn mng in thoithng qua th tn mt mem. Cc bng thng bo thng c chuyn dng cc nhm c bitv c th mang tn hiu, lu , v chng trnh.

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T chc a ra mt chui dch v my tnh nh x l bng lng, chuyn mn ha vic in hay cit kiu.

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B nh my tnh y lu mt k t d liu n. K t c lu trong mt byte ca b nhnh mt mng bit (ch s nh phn), dng mt m nh ASCII. Mt byte thng cha 8 bit v d,ch hoa F c th c lu nh mng bit 01000110. Kch c b nh my tnh c o bngkilobyte (1.024 byte) hay megabyte (1.024 kilobyte).


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B nh m

Khu vc dnh ring cho vic nhp d kin tc th, c s dng tng tc hot ng cachng trnh my tnh.

B nh m c th c xy dng t SRAM, n nhanh hn nhng cng t hn DRAM bnhthng. Hu ht cc chng trnh nhp vo vi cng mt ch dn v d liu ging nhau. Nuthng xuyn s dng cc ch dn v d liu c tr sn trong b nh m SDRAM th chngtrnh s hot ng nhanh hn. Trong trng hp khc, b nh m l DRAM nhng c sdng lu tr thng xuyn s dng cc ch dn v d liu th s c lu tr tr li mt cchn gin. Nhp d liu vo DRAM nhanh hn lu tr tr li v li mt ln na chng trnh chynhanh hn. Kiu b nh m ny thng c gi l m a.

Thit k vi s tr gip ca my tnh

My tnh s dng trong to dng v thit lp cc bn v thit k. CAD cng cho php ngi sdng thc hin nhng tc v nh kim sot nhng thit k phc tp mt cch t ng hay lmlinh hot thm khng gian ba chiu ca thit k. H thng CAD c s dng rng ri trong kintrc, in t v k thut (th d trong cng nghip sn xut xe hi, ni m gi y cc thit k muxe c s tr gip ca nhng chic my tnh). Mi quan h pht trin ny c gi l CAM

Sn xut vi s tr gip ca my tnh

My tnh c s dng kim sot qu trnh sn xut, c bit l kim sot my cng c v cc

ngi my trong cc x nghip. Trong mt s nh my, ton b h thng thit k v sn xut ckt ni vi nhau mt cch t ng t CAD n CAM. Mng linh hot CAD v CAM trong sn xutn cc my bn hng v phn phi vi phng php ny c th cho php sn xut mt s lnghng ha tiu dng vi gi thp hn.

Bng ghi tm

Tp tin tm thi hay vng nh ti d liu c th c lu tr trc khi c sao chp vo mttp tin ng dng. V d nh c dng trong cc thao tc ct v dn tp tin.

Ngt tn hiu

C PHT SINH BI NG H IN T BN TRONG MY tnh.

Tn s ng h

Tn s ca ng h in t bn trong my tnh. N sinh ra mt dy xung in c b phn iukhin s dng ng b ha cc b phn ca my tnh v iu ho chu trnh thc hin - tr v

theo cc ch dn ca chng trnh c x l. Mt s c nh ca cc xung thi gian c i


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hi thc hin tng lnh ring. Vn tc ti my vi tnh c th x l cc lnh s ph thuc votn s ng h ny. Tn s ng h c o bng megahertz (Mhz) hay triu xung ng trong 1giy. My vi tnh thng c tn s ng h 8 - 50 MHz.

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Ngn ng chng trnh my tnh cao cp vi nhiu chc nng a dng c pht trin vo uthp nin 70 v trc c gi tt l BCPL. C c s dng trc tin nh l ngn ng hotng h thng Unix, thng qua n v t tr nn rng ri b xa Unix. N hu ch trong vic sontho nhanh v cc chng trnh hon thin, c hai h thng cng hot ng (iu hnh hot ngca my) v gn lin vi nhau.

Chng trnh ngn ng cao cp s dng gn vi nh hng mc tiu.

- Cal - Vit tt ca s c mt ca my tnh trong hc tp) my tnh s dng trong gio dc v oto. My tnh trnh by cc ti liu hng dn sinh vin v hi v thng tin c a ra, nhngcu tr li ca sinh vin v bi hc c xc nh r rng v lin tc.

Chuyn tr v, mt m s c bit (ASCII gi tr 13) l chuyn con tr mn hnh my in v imbt u ca dng hin ti. Hu ht cc t hin th v h MS-DOS hot ng s dng s kt hpca CR v dng cung cp (LF-ASCII gi tr 10) th hin cho s chuyn v kh khn. D sao hUnix ch s dng LF v do cc tp tin chuyn i gia MS-Dos v Unix cn mt chng trnhchuyn i.

Vit tt ca: Comite Consultatif International Telephonique et. Telegraphique.

Tng tc a compact: (Vit tc cho tc ng qua li ca a Compact) kh a Compact phttrin bi Philips vi s sung cp kt hp ca truyn hnh, m thanh, ch u v hnh nh. Vi nh ch yu cho th trng tiu dng c s dng trong h thng kt hp ca my tnh v vtuyn truyn hnh. S chn la kh a l s tng giao ngi - my ca truyn hnh (DVI).

(S thu a Compact) kiu a Compact c th ghi li d liu trn (SO SNH VI CD-ROM) .A L S KT HP CA CNG ngh t tnh v quang hc. Trong khi thu a, tia

lade chiu trn b mt a c sp xp theo quy nh.

B nh ch c dung lng. (Vit tc cho a Compact b nh ch c). My vi tnh lu tr sngch pht trin ca cng ngh m thanh l a compact. N gm c mt a nha cng trng a

Compact. N gm c mt a nha cng trng kim loi, trn s thng tin nh phn c khc


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axt theo trt t ca lm rt nh. Ri n c th c c bng cch cho MT CHM TIA SNG IQUA TRN MT A. A CD-ROM IN HNH CHA KHONG 550 MT A. A CD-ROMin hnh cha khong 550 magebyte d liu, v c s dng xy dng s lng ln nhngvn bn v th nh nhng b sch bch khoa, catalog v s sch k thut. Thu a CD-R cngc pht trin. Xem nh a CD-I.

Mt trong hai h thng teletext ca Anh (ci kia l Teletext) hoc nhng tp ch hng khng phttrin bi BBC v pht ln u tin nm 1973.

B x l trung tm, b phn cu thnh chnh ca my tnh, phn cu to th hin chng trnhring v iu khin hot ng ca cc phn khc. N thng c gi l trung tm iu hnh haykhi bao gm t hp mch in ring, mt d kin cha trong mch vi tnh.

CPU c ba b phn cu thnh chnh: b phn s hc v l-gic (ALU), ni thc hin mi tnh tonv l-gic hc; b phn iu khin; gii m, ng b ha v th hin ch dn chng trnh; v bnh nhp d liu tc th: n lu tr cc d liu v chng trnh trn my tnh hin ti lm vic.Tt c cc cu hnh thnh ny gm nhng ghi nhn ni v tr b nh lu tr cho nhng mc chc bit. Nhng ghi nhn bao gm s tch ly, ghi nhn ch dn v ghi nhn s iu khin lintip.

Giao din centronics, tn ring cho mt tip gip song song (Centronics l nh sn xut my inquan trng trong bnh minh ca my tnh hin i).

Thit b tng hp ha mu (Vit tc cho s iu hp mu sc v th) h thng biu dinmu u tin cho my tnh c nhn (IBMPC) v cc my tng hp. N c thay th bi EGA,VGA, SVGA v XGA.

K t: Mt trong nhng k t c th c hiu din trong my tnh. N bao gm cc ch ci, s,khong trng, du chm v cc k hiu c bit khc.

My in k t. My in vi tnh in mt du hiu ti mt thi im.

Tp hp k t. Tp hp y cc k t c dng trong 1 chng trnh c nhn ra bi myvi tnh. N bao gm cc cha ci, ch s, khong trng du chm v cc k hiu c bit khc.


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Kim tra dng l t. S kim tra c hiu lc chc chn rng mt chi tit d kin c a vokhng cha cc du hiu khng c gi tr. V d nh 1 tn c a vo c th c kim tra chc chn rng n ch cha cc ch trong bng ch ci hoc ngy thng c 6 ch s a vo c

th c kim tra chc rng n ch cha cc s.

Ch s kim tra. Ch s c gn vi mt m s quan trng nh kim tra ph chun.

Tng kim tra. Tng s kim tra cc chi tit c bit ca d kin m khng c ngha khc. Tngny c dng nh mt du hiu nhn din rng d liu c a vo hoc chuyn i 1 cchchnh xc. N c dng trong vic chuyn i 1 cch chnh xc. N c dng trong vic trao i

thng tin v v d nh trong chng trnh tng thut. Xem validation.

Vi mch in t, tn gi khc ca integrated circuit, l 1 mch in t y trn mt tm silic(hay mt cht bn dn khc), tinh th ch vi milimt vung.

My tnh c tp lnh phc tp. (Vit tt cc ch u c complex instruction set computer). Thit bvi x l (b x l trn mt vi mch in t n) c th thc hin c mt s ln cc lnh ca mtm my - v d Intel 80486. Thut ng ny c a vo phn bit nhng vi mch in tny vi thit b vi x l RISC (Reduced

Inatruction Set Computer) iu khin mt tp hp cc lnh nh hn.

Cu trc khch - ch. H thng mng li trong vn hnh theo di cc d liu c tch rakhi chng trnh s dng d liu . Mi my vi tnh hoc l ngi ch, cha cc d liu hociu khin cc hng ca h thng - v d nh my in hoc mng li, hoc khch hng trn qun l cc chng trnh ng dng.

Bn dn b oxit - kim loi: (Vit tt ca Comlementary metal - oxide Semiconductor). H cc b vimch in t c s dng rng ri trong vic thit lp cc h thng in t.

(Vit tc ca Cyan - Magenta - Yellow - black: xanh l cy - ti - vng en). S phn ly 4 muc dng trong hu ht cc qu trnh in mu. C TRNG TRN MY TNH L MN HNH,TUY NHIN THNG s dng phng php RGB b sung thm v v th s chuyn i thngl cn thit b phn cho ra kt qu in hoc trn my in mu hoc phn tch.


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Vit tc ca Computer numerical control

Cp truyn ng trc, cp truyn in gm dy dn in rn c cch in v bao quanh bngng hay bao bo v rn. N c th truyn nhng tn hiu tn s cao c s dng trong tivi, inthoi cc phng tin truyn thng khc. N ang c thay th bi si cp quang hoc cp cpxon trn.

(Vit tc ca Commnon Business Oriented language). Ngn ng chng trnh my tnh cao cp,c son tho vo cui nhng nm 1950 dnh cho cc vn x l d liu thng mi, n tr thnh ngn ng chnh trong lnh vc ny. Cc a im ca

COBOL rt thun tin cho cc tp tin s hc iu khin v kinh doanh. Nhng lnh ca chngtrnh c vit bng ngn ng ny m rng vic s dng cc t v trng rt ging vi cu vnbng TING ANH. IU NY LM CHO COBOL TR THNH MT TRONG nhng ngnh dhc v d hiu nht.

Vit tt ca Computer output on micro - film/microfiche.

Y BAN T VN V IN THOI V IN BO quc t. T chc quc t xc nh cc tiuchun v vn bn truyn thng quc t cho cc d liu truyn thng, bao hm c fax.

Ngn ng mnh lnh. Tp hp cc lnh v quy tc iu khin cch s dng ca chng m theo ngi s dng iu khin 1 chng trnh. V d nh h thng thao tc hoc c cc lnh nhSave v delete, hay 2 chng trnh v danh sch tr lng cho nhn vin c th c cc lnh thm v sa i cc h s nhn vin.

GIAO DIN DNG LNH. NG PHN GII DA trn cc k t trong li nhc nh cbiu din trn mn hnh m ti ngi s dng gi mt lnh bng b phn chuyn i nhngphn xc nh, y nu mt im ca mnh lnh c gi tr th n s c thc hin.

A COM-PACT. A quang hc, khong 12 cm chiu ngang, c dng lu tr cc thng tinbng K THUT S. A C LM BNG NHM C PH 1 lp nha trong sut. Cc vt lmrt nh c khc bng lade trn b mt kim loi c dng lu tr d liu trong m nh phn.

Trong lc pht li, chm lade s c m hiu v to ra cc tnh hiu l bn sao gn nh hon ho


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ca bn gc. Xem CD-ROM, CD-I v CD-R.

Chng trnh bin sonChng trnh my tnh dch cc chng trnh c vit bng ngn ng mc cao sang mt mmy. Chng trnh ny dch mi lnh bng ngn ng mc cao sang mt s lnh mt m mytrong 1 qu trnh c gi l s bin son v to ra mt chng trnh hon ton c lp c thqun l c bng my tnh m khng cn s c mt ca chng trnh gc.

Cc chng trnh bin son khc nhau cn cc ngn ng cao cp khc nhau v cho cc my tnhkhc nhau. Tri vi vic s dng chng trnh dch, vic s dng chng trnh bin son cnthm 1 cht thi gian a ra 1 chng trnh bng mt m my phi c bin son tr li saumi thay i hoc hiu chnh. Tuy nhin vi 1 ln c bin son, chng trnh mt m my schy nhanh hn chng trnh c dch nhiu.

My tnh. Thit b in t c th lp chng trnh x l v thc hin cc php tnh v ccnhim v thao tc bng k hiu khc. C 3 dng chnh: my tnh k thut s, hot ng vi ccthng tin c m ha nh cc s h nh phn; my tnh tng t: lm vic vi cc i lngbin i lin tc; v my tnh lai: c cc c tnh ca c 2 loi trn.

C 4 cch phn loi my tnh k thut s, tng ng vi kch thc v mc ch s dng ca n:my vi tnh (k c my tnh xch tay) l loi nh nht v thng dng nht, c dng trong cc cs kinh doanh nh, ti nh v ti cc trng ph thng; my tnh mini c dng trong cc c skinh doanh c trung v cc khoa ca trng i hc (mc d s khc bit gia my tnh v mytnh mini ang bin mt); v dn my tnh thng c th phc v cho vi trm ngi s dng

ng thi, thng c s dng trong cc t chc ln nh cc cng ty quc t; v sin my tnh,c s dng ch yu cho cc nhim v khoa hc ht sc phc tp nh phn tch kt qu ca dbo thi tit.

Tr chi trn my tnh. Tr chi c iu khin bng my tnh trong my tnh i chi vingi chi. Tr chi my tnh s dng nhng hnh nh nhanh v sng ng trn mn hnh, v cm thanh tng hp.

Th h my tnh. Mt trong 5 nhm tng qut trong cc my tnh c th c phn loi th hth nht l nhng my tnh sm nht ra i vo nhng nm 1940 v 1950, c ch to t ccmch in t dy v n in t; Th h th hai c t nhng nm 1960, da trn cc transistorv mch in; Th h th ba c t nhng nm cui ca thp k 1960, s dng cc mch vi in tv thng c bn nh h ca cc my tnh, v d nh loi IBM 360; th h th t s dng cc

b vi mch x l, cc t hp vi in t ln (LSI) v cc ngn ng lp trnh tinh vi, n vn cn c


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dng trong nhng nm 1990; v th h th 5 da trn vic x l song song v cc t hp vi int rt ln (VLSI), hin ang c pht trin.

HA MY TNH. S DNG MY TNH BIU din v lm vic vi cc thng tin dnghnh v. Cc hnh v c lu li trong my tnh nh cc ha bng mnh hay ha vect.Cc hnh trn my tnh c s dng ngnh cng tng trong CAD (computer-aided design), v to ra cc m hnh v s m phng trong k thut, kh tng, y t v phu thut, v cc lnh vckhoa hc khc, cng nh trong vic xut bn.

IU KHIN K THUT S MY TNH. IU KHIN CC MY CNG C, THNG L CCMY THAY bng my tnh. Mu thit k cng vic cho my lm theo, thng l lin quan n victhc hin cc hnh ng c lp li nhiu ln, c m t bng cch s dng ngn ng lptrnh mc ch c bit.

Micro fiche (COM): Vi phim xut t my tnh. K thut to kt qu u ra ca my trong dngrt c ng v rt gn.

Chng trnh my tnh cc lnh c m ha cho mt my tnh.

S m phng trn my tnh. S biu din 1 tnh hung c thc ca i sng trong 1 chng trnhmy tnh. Vi d nh chng trnh c th m phng s lu thng ca cc khch hng n 1 ngnhng.

Ngi s dng c th thay cc bin s, nh s ngi thu ngn ang lm vic, v xem xt hiuqu.

S m phng phc tp hn c th to c cch thc xy ra ca mt phn ng ha hc haythm ch mt v n ht nhn. My tnh cng iu khin hot ng ca my mc. V d nh vt mphng chuyn bay to nn hot ng ca mt my bay thc v cho php hun luyn trong iu

kin an ton. S m phng bng my tnh c ch khi n qu nguy him, tiu dng nhiu thi gian,hay n gin l khng th thc hin c mt thc nghim hay kim tra tht s.

Trm nhp, nhn tin t my tnh. Cng c m nh n ngi vn hnh my chuyn tin c vimy tnh.

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S phc v d liu cho cng chng rng ri. N c s dng cho th in t v ba tp san.


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H thng sp xp. Cch thc m mt h thng, a cng hay/v a mm c b tr. S sp xpti thiu thng c gn cho 1 s ng dng c bit, v n thng bao gm bn k chi tit cab x l, a v kch thc b nh, v thit b ngoi vi c yu cu.

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T hp ca bn phm v mn hnh ( cng c m t nh 1 trm nhp V NHN TIN). I VIH THNG NH UNIX TH CH C 1 h thng bng iu khin m t h thng c th cthc hin, trong khi c th c nhiu trm nhn v nhp tin c s dng.

BUS IU KHIN. NG I BNG IN C s dng truyn cc tn hiu iu khin.

K t iu khin. K t bt k c to ra khi n phm iu khin (Ctrl) cng lc vi 1 phm khc(thng l phm ch ci). Cc k t iu khin to thnh 32 k t ASCII u tin v hu ht uc ngha xc nh i vi h iu hnh c s dng. Chng cng cn c dng trong t hp to ra s kim sot khun kh kch thc trong nhiu thit b x l t, mc d ngi s dngc th khng a chng vo mt cch r rng.

Tng iu khin. S kim tra ph chun trong tng s hc ca 1 vng xc nh t 1 nhm

thng tin ghi li c tnh ton. Tng ny c a vo cng vi d liu m n lin quan n.Chng trnh tnh ton li tng ny v so snh n vi 1 tng khc c a vo chc chnrng khng mt sai st no c thc hin.

N V IU KHIN. MT THNH PHN CA KHI x l trung tm, n gii m, lm ng b viu hnh s ch dn chng trnh.

B ng x l: B x l b sung, chc nng ca n l cng hp vi khi x l trung tm cungcp 1 chc nng xc nh. Hai b phn x l ph ph bin nht l b x l ph ton hc, cdng tng tc tnh ton v b x l ph th, c dng hon thin vic x l cc th.

Chng sao chp. K thut c dng ngn chn s sao chp bt hp php mt chng trnh.S bo v trong sao chp khng cn c c s dng thng xuyn nh trc y v n cngngn chn s sao chp hp php ( vi cc mc ch d tr). K thut thay th n ngn chns sao chp bt hp php l s dng cc mt lnh.


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S h hng d liu. S c mt ca cc h hng trong d liu. Hu ht cc my vi tnh u sdng vng cc l trnh thm tra v ph chun ngn chn d liu b h hng i vo h thngmy tnh hoc pht hin cc d liu h hng tht s c mt trong my.

Vit tt ca control program/monitor hay control program for microcomputers). Chng trnh iukhin mn hnh gim st. Chng trnh iu khin mn hnh hay chng trnh iu khin dnhcho my vi tnh.

Mt trong nhng h thng iu khin hot ng s khi nht dnh cho my vi tnh. Chng trnhny do Gary Kidall vit ra, ng l ngi t nn mng cho vic nghin cu k thut s, v n trthnh tiu chun i vi cc my vi tnh da trn cc b mch vi x l Intel 8080 v Zilog Z80 8bit. Trong nhng nm 1980 chng trnh ny c thay th bng chng trnh MS-DOS caMicrosoft, c vit cho cc b mch vi x l 16 bit. N cn c s dng trong phm vi ca th

gii my vi tnh c nhn h Amstrad.

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VIT TT CA CENTRAL PROCESSING UINT: N V X l trung tm.

S phn tch ng ti hn. Qui trnh c dng trong vic qun l cc n phc tp lmgim ti a thi gian cn thit. S phn tch ch cho thy nhng n con no phi c honthnh trc khi bt u 1 n con khc. Bng cch xc nh thi gian cn thit cho mi n

con ring bit v mi quan h gia chng, ta c th lp bng k hoch ch r rng lc no th 1 n con ny cn c bt u v kt thc hon thnh c ton b n 1 cch hiu qu nht.Cc n phc tp c th lin quan n hng trm n con, v vic ng dng my tnh phntch ng ti hn c s dng rng ri nhm lm gim thi gian v cng sc trong vic phntch chng.

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Con tr, im nhy trn mn hnh ch v tr. Trn mn hnh my tnh, k hiu m ch v tr vohin hnh (v tr m k t k tip s xut hin). Trong cc ng dng da trn k t, nthng l mt khi ch nht hoc k t c gch di, v n nhp nhy. Trong cc mt phn giic hnh nh, n c th thay i hnh dng da trn ng cnh.

NG TR: T HP CC RNH TRN TT C CC a to nn 1 a c nh m c th thuc khng cn s chuyn ng ca u c/vit


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B chuyn i t k thut s sang k thut tng t.

U IN TRONG MY IN T MY TNH HAY MY nh ch cha mt a trn nh bng kim loihoc nha tng hp, gm nhiu nan hoa (nh cc cnh ca hoa cc), mi nan hoa mang mt kt c chm ni trn b mt. Bnh xe hnh hoa cc c quay cho n khi nan hoa mang k tcn thit i din vi ruy bng tm mc; Lc mt ci ba s g nan hoa vo dy ruy bng, li du n ca k t trn giy bn di.

U IN HNH HOA CC C TH C THAY I TO ra cc kiu ch khc nhau. Tuynhin my in vi u in hnh hoa cc khng th in c th v ch c th in nhiu hn mt kiuch trong cng mt ti liu nu u in c thay i, mt s phn mm cho php thc hin iuny.

D liu

Cc s kin, hnh nh v k hiu, c bit khi c lu tr trong my tnh, thut ng ny thngc s dng ch cc s kin th cha c x l, khc vi thng tin ch mt ngha hay sdin gii c p dng.

NG D LIU

NG IN, C DNG VN CHUYN D LIU gia cc thnh phn ca my tnh.

Thu nhp d liu

S thu nhp thng tin cho vic phn tch v x l bng my tnh. Cc d liu c thu thp tng - v d nh, bng mt b cm bin lin tc theo di cc iu kin vt l nh nhit ; hocc thu thp bng tay - v d bng cch c dng c o in.

S truyn d liuVic gi v nhn d liu thng qua mt mi trng trao i bt k, nh ng in thoi. Thutng ny thng ng ch d liu l cc s (nh d liu my tnh) hn l cc kiu khc (nh ccthng ip bng ging ni). Tuy nhin trong h thng ISDN (Intergrated Ser Vies

mng li phc v t hp s), tt c cc d liu bao gm c ging ni v hnhnh video, u c truyn bng k thut s.

S nn d liu.


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K thut lm gim ni lu tr cn thit cho mt s lng d liu xc nh. chng bao hm vick hiu ha cc t (trong cc t thng s dng c lu tr dng mt m ngn gn hn),thay i di ca n v thng tin (bit) (trong cc k t ph bin c biu din bng t n vthng tin hn vi k t thng) v m ha chiu di (trong mt ngha lp li c lu tr mtln).

T in d liu

Tp tin c dng trong s qun l c s d liu, n mang d liu v cc d liu, v d nh danhsch cc tp tin, s cc s kin trong mi tp tin, v cc dng ca mc tin. Cc t in d liuc phn mm ca c s d liu s dng c th thu nhn cc d liu.

Biu d liuBiu minh ha cc l trnh c th m d liu c th ly qua mt h thng hay chng trnh.

A D LIU VO

Vic a d liu vo mt h thng my tnh

Nhp d liuQu trnh thu nhp v ghi, thng l t ng, mt dy cc gi tr cho vic x l v phn tch bngmy tnh sau ny.

S chun b d liu

S chun b d liu cho u vo ca my tnh bng cch chuyn n sang mi trng my c thc c. Qu trnh ny thng lin quan n vic nh my d liu bn phm cho n cth c chuyn trc tip vo bng hay a.

Cc phng php thu nhp d liu trc tip khc nhau nh mt m thanh, s nhn bit du hiubng th gic, v s nhn bit k t bng th gic c a ra gim hoc loi tr vic chun bd liu di dng trc khi a vo my tnh.

S x l d liu

Vic s dng cc my tnh thc hin cc cng vic Vn phng nh kim sot kho hng, lpdanh sch tr lng cho nhn vin, v gii quyt cc n t hng. H thng x l d liu l mth thng nhm tiu biu, chy trn cc my tnh ln. S x l d liu i lc cn c gi l sx l d liu in t (EDP).


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S bo v d liu

S bo v an ton cho cc thng tin v cc c th c lu tr trn cc MY TNH. IU NYI HI CC C S D LIU ca my tnh cha cc thng tin ring v c nhn phi c ghili, v nhng ngi s dng ch x l nhng thng tin chnh xc v vn gi nguyn cc thng tinch cho mt giai on cn thit v cho nhng mc ch xc nh.

S an ton d liu

S phng ngn chn s mt hay dng sai d liu, hoc tnh c hoc c . Chng bao gmcc phng thc m bo m rng ch nhng ngi c cng nhn mi c th vo c hthng my tnh hay cc tp tin, v cc quy trnh thng xuyn dnh cho vic lu li v d tr ccd liu. C th cung cp cc tp tin c tm li hoc thit lp li trong trng hp mt hoc lmh hi d liu. Mt s cc k thut kim tra v gim st cng c dng ngn nga cc dliu b mt i hoc b lm hng.

Gi tr d liu cui

Gi tr c bit c dng nh du s kt thc mt danh sch cc chi tit d liu c avo. My tnh c th pht hin rng d liu khc vi cc d liu a vo theo nhiu cch. V dnh mt s m c th c dng lm tn hiu ch s kt thc ca mt danh sch gm cc sdng.

chng trnh base

Hc cc chng trnh ca my vi tnh c dng lm vic trn mt s lng d liu ln; ncng l ngn ng th h th 4. Trong phin bn th nht. dBase II - xut hin vo nm 1981, ntr thnh nn tng cho tiu chun ca cc ng dng ca c s d liu, c gi l Xbse.

S sa cha li

Tm v loi b cc li t mt chng trnh hay h thng my tnh.

H s thp phn

H thng s c s dng ph bin nht, vi c s 10. Cc h thng khc ch yu c s dngtrong tnh ton v bao gm h nh phn, h thng tam s v h thng mt s.

Bng quyt nh

Phng php m t mt quy trnh dnh cho mt chng trnh i theo. Da trn vic so snh cc


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kt lun c th v kt qu ca n. N thng c s dng nh mt phng tin tr gip trongvic thit k cc h thng.

Phn trn ca bng cha cc iu kin rt ra kt lun (v d mt s m hoc dng v nhhn mt), v phn di m t cc kt lun khi gp nhng iu kin ny. Chng trnh ny hoc

kt thc hoc lp li qu trnh hot ng.

S lp trnh khai bo

S lp trnh m khng m t cch gii quyt vn , nhng li m t cu trc hp l ca vn .N c s dng trong ngn ng lp trnh Prolog. N c s dng trong ngn ng lp trnhProlog. Vic chy mt chng trnh nh vy ging nh l s chng t mt li tuyn b hn lchy theo mt quy trnh.

B phn gii m

Mch in t c dng chn mt trong mt s ng d liu c th. V d nh cc b giim thng quen vi cc d liu trc tip vi cc vng nh ring bit trong b nh tc thi camy tnh.

My tnh chuyn bit

My tnh c ch to nm trong mt cng c khc cho mc ch iu khin hoc cung cp thng

tin cho cng c . Cng dng ca n c tng nhanh nh s ra i ca cc b vi mch x l:my git, ng h in s, xe hi, my ghi hnh video..., ngy nay tt c chng u c cc bmch x l ring.

Chp lin

Qu trnh sp xp li cc d liu trn a sao cho cc tp tin khng b lu tr trong cc vng nh.

Xa i, gch iS xa b mt k t khi mt tp tin. S xa b mt tp tin thng c ngha l xa mc t trongth mc ca n hn l thc s xa b n khi a. Ngy nay nhiu h thng c phng tinkhng xa b cho php lu tr li cc mc t th mc. Trong khi cc tp tin b xa b khng th bxa i khi a, chng c th c vit chng ln.

Trnh lm vic Dekstop

S biu din cc h thng tp tin bng biu th, trong cc ng dng v cc tp tin c biu

din bng cc hnh v (cc biu tng m c th c gi ra bng cch nhp n hoc p conchut).


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In bng my vi tnh

Vic s dng my vi tnh xp ch vi cp bc nh v sp xp trang. Cc h thng ny c khnng to ra cc trang trong khoan chun b (cc trang chun b sao chp v in) cha cc biu v vn bn, vi b vn bn c cc kiu c v kch thc khc nhau. Cc trang ny c thc xem li ton b trn mn hnh trc khi c in trn my in lade.

(Vit tt ca direct information access network for Europe)

S THU THP THNG TIN CUNG CP CHO MNG MY TNH CA CHU U.

My tnhMy tnh c hc c thit k (v c ch to mt phn nm 1822) bi nh ton hc ngi Anh,Charles Barrles, to ra cc bng tnh tui th ng tin cy. Tin thn ca my phn tch, n tnhc cc hm s ton hc bng cch gii. S khc nhau gia cc gi tr c cho trc ca ccbin s trong cc chng trnh.

Ch s

S bt k t 0 n 9 trong h thp phn. Cc c s khc nhau c phm vi cc ch s khc nhau.V d nh h 16 s c cc ch s t 0 n 9 v t A ti F, trong khi h nh phn ch c 2 ch s l

0 v 1.

K thut s

Thut ng c ngha l m ha bng s. H thng k thut s s dng 2 trng thi, hoc cc xungin th m/tt hoc cao/thp gii m, nhn v truyn thng tin. S biu din k thut s ch racc gi tr ring bit nh cc s (khc vi cc k hiu tng t, nh cc on lin tc ca kim chtrn bng s).

Bng ghi m bng k thut s

Bng tn cha n vi nige byte thng tin, c dng d tr. Cc d liu c truyn i vimc vi megabyte trong mt pht.

My tnh hin s

Cng c tnh ton hot ng trn h thng 2 trng thi, s dng cc k hiu c m ha bngch s dng h nh phn (cc s c cu thnh t cc t hp ca cc ch s 0 v 1).


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Truyn d liu bng k thut s

Cch thc truyn d liu bng cch bin i tt c cc du hiu (hnh nh, m thanh hoc t)thnh cc m s (thng l h nh phn) trc khi truyn i, ri li bin i tr li nh ban u ni nhn d liu. Phng php ny loi tr c s mo m hay thoi ha cc tn hiu trong qutrnh truyn, lu tr v x l.

B bin i - tng t

Mnh in t bin i cc tn hiu s thnh tn hiu tng ng. Mch in t ny c dng bin i u ra bng s t mt my tnh thnh in th tng ng cn thit sinh ra mtm thanh t b khuych i quy c.

S tng tc video - s

K thut c s dng lu tr cc hnh nh ca ti vi trn my tnh. N s dng k thut nn dliu v cc b mch x l c bit.

B s ha

Cng c bin cc tn hiu hnh nh video thnh dng s sao cho cc nh video c th c avo, lu tr biu din v thao tc bi mt my tnh. Thut ng ny i lc cng c dng ch

mt khi th.

K t c bit

K t phi l s v ch ci, nh du sao, du n hay mi tn. Cc k t ny c t hp thnhcc phng ch Ti bt v dng thng s dng vi cc b x l v cc chng trnh v th.

Vit tt ca documen imgge processing: x l ti liu nh

S truy cp trc tip

Mt dng truy cp tp tin. tp tin truy cp trc tip c cha cc ghi chp c th c truy cp trctip nh my tnh v mi ghi chp c a ch ring ca n trn a lu.

Truy cp b nh trc tip

K thut c dng chuyn d liu n v i khi cc thit b bn ngoi m khng cn i qua


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khi x l trung tm v v th tng tc truyn. S truy cp b nh trc tip c dng cho cccng c nh b qut hnh.

Th mc

S xp nhm ca tn cc tp tin di tn th mc, cng vi cc thng tin cung cp cho my tnhc th tm li c nhng tp tin ny t vng lu tr m.

A

Mi trng ph bin lu tr d liu (mt loi thay th l bng t). A T C QUAY VIMT TC CAO TRONG A KHI u c/ghi (m my xem hoc ghi a) i qua trn bmt ca n s c hay ghi li cc bin i t gii m d liu. Gn y, cc a quang hc nhCD-ROM; CD-R v WOEN c dng lu tr d liu bng my tnh.

CC A T C MT S DNG. A CNG C NH c to bn trong khoang a, thngtrc xp chng ln nhau. Cc a cng c th ly i c thng c trong cc h thng my tnh.Cc a c cha hoc ring bit hoc nh mt khi xp chng trong mt hp bo v bngnha tng hp, v c th c ly ra khi khoan a v gi S DNG SAU NY. A MML DNG PH BIN nht ca s lu tr dng cho my vi tnh. N c kch thc v dung tch nhhn a cng nhiu v c gi nh vy v n c sn xut t mng nha tng hp mng cph mt lp vt liu t tnh.

A

Dng c c hc c d liu t a v ghi d liu vo a. Trong trng hp a cng, a baohm c chnh a cng.

S nh dng a

S chun b mt a t trng cc d liu c th lu tr c trn n, cc d liu c ghi trnb mt a trn nhng ng trn, mi ng c phn chia thnh mt s cung. Trong vic nhdng mt a, h thng hot ng ca my tnh s gip iu khin cc thng tin nh s ng v

s cung gip cho cc d liu c lu tr c th c truy cp trc tip bi b phn trong a.Mt s h thng x l t c hn dng cc a mm c cung ng, trong vic nh dng ac xc nh bi cc l trong a. Ngy nay, tt c cc h thng my tnh u s dng cc acung mm n hoc c nh dng trc lc bn hoc c nh dng bng cch s dngchng trnh tn dng c cung cp vi mi h thng my vi tnh hot ng.

Nhn hiu my nghe a la de

Nhn hiu thng mi ca hng Sony dng cho my nghe a lade xch tay, tng ng vinhn hiu Walkman, n cng l nhn hiu ca kiu my c mng tinh th lng cho cc a d liu.


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Chng trnh nhm cc on nh li

S x l phn tn

S x l bng my tnh m s dng hn mt my tnh tin hnh mt s ng dng. N baogm vic x l bng cch s dng mng li vng, kin trc khch/ch v x l song song.

To lay ng, lm lung linh

K thut dng cho cc mu chm gch khc nhau trn th, biu to n tng ca cc

vng b che khut. Mi du chm u c cng kch thc v cng m.

Ti liu, chng t

D liu lin quan n mt ng dng ring. V d, nh ti liu vn bn c th c sinh ra bi bmch x l v ti liu biu c th c sinh ra vi khi CAD. Ti liu OMR hay OCR l ti liutrn giy cha cc d liu c th c a trc tip vo my tnh nh s dng mt b phn cti liu.

Cung cp d liu, su liu

Thng tin vit lin quan n mt chng trnh my tnh hay mt khi ng dng, su liu thngc chia thnh phm tr: su liu chng trnh v su liu s dng.

Su liu chng trnh l s m t hon chnh k thut ca mt chng TRNH. C SONTHO NH MT PHN MM C vit v d nh gip s duy tr hoc pht trin sau nyca chng trnh . Su liu s dng gii thch cch thc vn hnh phn mm .

S x l ti liuS phn tch cc ti liu v lu tr trn CD-ROM. Cc nh phn tch c xp theo mc lc, m bo s truy cp nhanh hn, kh nng trn giy HOC DNG CC NH. IU NYTNG T NH S LU tr ti liu c nhiu cng ty iu chnh phc v khch hng tthn v gim khong khng lu tr cn thit.

B phn c ti liu

Thit b u vo c cc du hiu hay k t, thng dng c chun b trc v cc ti

liu. Cc thit b nh vy c dng nhn d liu bng s nhn bit cc du hiu quang hc,s nhn bit cc k t quang hc v vic d du hiu.


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Thit b bo m vic s dng hp php ca mt chng trnh ng dng. N thng gn vob phn in ca my vi tnh v chng trnh s khng chy c nu khng c mt n. Thngcng cn thit phi bt my in.

H iu hnh Dos. H thng iu hnh my tnh c thit k c bit cho vic s dng vi alu tr; n cng c dng ch h thng iu hnh ring MS-DOS.

My in kim

My in ca my tnh sinh ra mi l t ring bit bng cch in mt hnh hay MT KHUN MUGM RT NHIU CHM NH. U IN L mt ng thng ng hay mt khi gm 9 hoc 24kim in. Khi u in c chuyn ng t bn ny sang bn kia trang giy, cc kim in c y vpha trc mt cch chn lc, nh vo ruy bng tm mc v to nn cc hnh mu gm ccchm cho mi l t trn t giy nm bn.

My in kim linh ng hn my in c u in hnh hoa cc v n c th in c th, hnh v v vnbn trong nhiu dng ch khc nhau. My in ny c mua v bo tr r hn my in lade, v vcc kim ca n g ln giy bng phng php vt l nn c th to ra cc bn sao bng giy than.Tuy nhin n gy n o khi hot ng v khng th to bn in cht lng cao nh cc my inkhng c s va chm trc tip.

N I

NHN (N V TH NT NHN TRN CON CHUT) 2 LN LIN TIP. N i trn mt biutng c bin din trn mn hnh nn c s dng khi u mt ng dng.

S chnh xc gp i

Dng k hiu im ni c chnh xc cao, c nhiu ch s thp phn c ngha. Thut ng gpi ch s chnh xc khng cht ch, c ngun gc t nhng s s dng hn 1 bit lm k hiuim ni tiu chun.

S chm trong mt inch

N V O NH C SINH RA TRN MN HNH MY tnh v my in.

DRAM (vit tt ca dynamic random - access memory)

B nh truy cp ngu nhin ng

Thit b ca b nh my tnh trong dng mch Silicon, thng c s dng bo m s truycp tc th trong b nh ca my vi tnh. B nh ny xa ni dung ca n nu chng khng cc v vit li sau mi 2 mili giy. Qu trnh ny c gi l s lm ti mi b nh. B nh truy

cp ngu nhin ny chm hn nhng r hn SRAM - l b nh mch silicon.


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Trnh iu khin

Chng trnh iu khin thit b ngoi bin ca my vi tnh. Mi thit b c ni vi my tnh cnmt chng trnh iu khin ring. Chng trnh iu khin ring bo m s lin lc gia mytnh v thit b. V d nh n thng c th ni nhiu dng my in khc nhau, mi my in c mtmt m hot ng ring ca n, vi loi my tnh ging nhau. IU NY THC HIN C VNH CHNG TRNH DN c cung cp dch cc lnh in tiu chun ca my tnh thnhcc lnh c bit cn thit cho mi my.

S kim tra bng tay

S kim tra s tin trin ca cc d liu, bng tay (vi v d nh giy v bt ch) mt chng trnhmy tnh trc khi chng trnh c chy trn my tnh.

In bng my tnh

Thit b u cui khng thng minh

B phn khng c kh nng x l ca ring n. N lm vic nh mt phng tin tip cn vi khix l trung tm chnh.

Kt sut

Qu trnh truyn d liu nhanh chng n b nh ngoi hoc n my in. N thng c thchin gip iu chnh cc sai st hay nh mt phn ca quy trnh khm ph h hng c thitk bo m s an ton cho d liu.

Bn phm dvorak

BN PHM NM NGOI CA MT MY NH CH BNH THNG ( Anh l Qwerty). Trongbn phm Dvorak cc phm thng c s dng nht c xp trung tm vic n phmc nhanh. Bn phm QWERTY nguyn c thit k cho nhng ngi nh my ch chm h khng gy ra s mc kt trn my nh ch c hc.

S trao i d liu ng. Mt dng giao tip x l qua li c s dng trong ca s Microsoft, nbo m s trao i cc lnh v d liu gia 2 chng trnh ng dng. S trao i ny c sdng ch yu cho cc d liu trc tip t ng dng ny sang ng dng khc, v d nh d liutri rng trong bng bo co c x l t. Trong ca s 3.1 s trao i ny c nng cao bngcc vt b sung c ni v gn vo.


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Th vin ni lin kt ng

Cc tp tin c chc nng thc hin m c th c np vo nhu cu ca ca s Microsoft v nikt ti thi im thc hin. Ca s Microsoft t n s dng cc tp tin ny iu khin bn phm, vd nh chng trnh x l ca ca s s dng cc tp tin ny cho cc chc nng nh sa lichnh t v kim tra du.


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Vit tt ca extended binary coded decimak interchange code.

M chuyn i thp phn m ha nh phn m rng. Mt m do hng IBM ngh ra, c dng lu tr v chuyn giao cc k t s v ch ci. N l mt mt m gm 8 n v thng tin (8 bit), ckh nng cha 256 k t khc nhau, mc d trong ch c 85 k t c xc nh trong trongphin bn tiu chun. N vn cn c dng trong nhiu my tnh hn, nhng ngy nay hu htcc my tnh nh v my vi tnh s dng mt m ASCII.

Phn chuyn tip in c to thnh bng cch ni mt s vng kim loi trn mt bn mch invi cnh ca bn v s dng chng cn trc tip vo cm in.

B ni ra thng c s dng ni bn mch chnh ca my tnh vi cc bn m rng cungcp cho my tnh b nh ph hoc cc phng tin khc.

(Vit tt electronic dissemination of information or electronic data interchange): s ph bin thngtin bng in t hay s trao i d liu bng in t.

S truyn thng tin c t chc trong dng in t gia cc h thng my tnh trong cc t chckhc nhau. EDI ch yu c dng trao i thng tin c lin h ti hot ng kinh doanh v trao i qu tin bng in t.

(Vit tt ca electrically erasable programmable read memory). B nh ch c lp trnh xa cbng in.

B nh ca my tnh c th ghi cc d liu v gi n li mt cch khng r rng. Cc d liu cth b xa i bi s tch in v d liu mi c ghi li. Mt s b nh loi ny phi c loi bkhi my tnh, b xa v c lp trnh li bng cch s dng mt thit b c bit. Mt s khc,c gi l b nh chp nhong, c th b xa b v lp trnh li m khng cn loi b n khimy tnh. Xem EPROM

(vit tt ca electronic funds transfer at proint of sale):

S chuyn qu tin bng in t ti im bn.

Vic chuyn qu tin t mt ti khon ca ngn hng ny sang ngn hng khc, bng cc phngtin in t. V d nh mt khch hng gi mt tm th plastic vo b phn my tnh ti im bnhng trong mt siu th, v cc ng in thoi c s dng t ng ghi n t ti khon ngn hng ca khch hng vo ha n.

(Vit tt ca enhanced graphics array):

B sp xp ha nng cao. H thng biu din bng mu, tt hn CGA, n cung cp 16 mu

trn mn hnh v mt s gii quyt vn 640 x 350, nhng khng tt nh VGA.


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(Vit tt ca executiveinformation systems):

H thng thng tin iu hnh.

S ng dng ca phn mm m tch thng tin t cc ng dng my tnh ca mt t chc, cc tptin d liu v a d liu vo dng m vic qun l i hi.

Bu in in t.

S ng dng cho php ngi s dng trn cng mt ch, hoc cc vng khc nhau trn thgii lin lc vi nhau bng cch gi cc thng ip thng qua hp th c t trong my tnhtrong vng hay xa. Cc thng ip thng c t trong vng nhn ca b nh m trongmy tnh trung tm cho n khi chng c ngi nhn thu ly. Cc mt m thng c sdng ngn chn s truy cp khng hp php ti cc thng ip c lu tr. Tn ti c h

thng chuyn th in t ring v th x hi. H thng cng cng thng c cung cp bicng ty truyn thng cng cng hoc trong hip hi vi cc tp san. Mng li cng cng baogm Internet compuserve, ARPAnet v

S giao tip gia cc mng li c thc hin qua cc cng vo.

Ch bn in t.

S xut bn thng tin thng c xem xt trn mn hnh hn l trn trang in. Cc thng tinc thu thp hoc t CD-ROM, hoc t mng li vng rng ln, t mt c s d liu tch bit.Cc thng tin nh vy phi c nh xut bn t chc v nh dng nh s dng cc h thngnh Acrobat v SGML.

IN T HC

Mt nhnh ca Khoa hc lin quan n s pht ra cc in t t cc cht dn c v cht bndn, n s hot ng tip theo sau ca cc in t ny v n vic ch to cc thit b in t.Thit b in t u tin l n in t hay ng chn khng, trong cc in t chuyn ngtrong chn khng, v dn n cc pht minh nh radio, tivi, radar v my tnh k thut s. S thayth ca cc n in t bng cc transistor kh nh v ng tin cy vo nm 1948 m ra cuccch mng trong s pht trin ngnh in t. Cc thit b in t hin i trn cc mch in, cclt tinh th rt mng c hng chc ngn hp phn in t.

Bng cch s dng cc thit b trng thi rn nh mch in, cc mch in t ht sc phctp c th c ch to ra, dn n s pht minh ra ng h hin s, my tnh b ti, my vi tnhhng mnh v b x l t.

(Vit tt ca electronic mail). Bu in in t.


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(Vit tt ca expanded memory specification). B nh m rng.

B nh phng

Chi tit ca phn mm hoc phn do cho php mt thit b bt chc chc nng ca thit bkhc. Phn mm m phng thng c dng cho php mt my tnh thc hin nhngchng trnh c vit cho my khc.

Dng tp tin bng hnh v c dng bi Post Script. N l mt tp tin PostScript vi cu trc cbit c thit k s dng bi cc ng dng khc.

S mt ha

Vic bo m s an ton ca d liu bng cch m ha d liu sao cho n v ngha vi nhngngi khng c quyn s dng m khng c phn mm gii m cn thit. Hai k thut c sdng rng ri nht l DES (data Encryption Standart: tiu chun m ha d liu) v RSA (s vittt da trn tn ca ngi pht minh).

Ngi, b phn s dng cui chng trnh my tnhC BIT N CH MT NGI NO S DNG mt chng trnh thc hin mt cngvic (nh tnh ton hay chi tr chi trn my tnh) hn l ch ngi vit ra chng trnh.

(Vit tt ca erasable progammable read - only memory). B nh ROM xa c v lp trnhc. Thit b nh ca my tnh trong dng vi mch in t m c th ghi cc d liu v gi n limt cch khng r rng. Cc d liu c th b xa b. Khi phi n ra nh sng cc tm, v d liumi li c ghi. Cc dng khc ca vi mch in t ca b nh my tnh l ROM (b nh ch cth c c) PROM (b nh ch c c, c th lp trnh c) v RAM (b nh truy cp ngu

nhin). Xem EEPROM.

(Vit tt ca electronic randomnumber indicator equipment)

Thit b biu th s ngu nhin bng in t. My c trm nghin cu thuc Tng cc Bu inAnh thit k v ch to chn mt dy s 9 ch s ngu nhin xc nh ngi thng giitrong x s quc gia.

Li hoc s h hng


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Sai st hoc s h hng trong phn mm hoc trong phn ca ngi s dng m lm chochng trnh ngng thc hin hoc sinh ra cc kt qu khng mong i. Cc li ca chng trnhc loi tr, trong mt chui cc quy trnh kim tra ban u ca ngi lp trnh, nhng mt s livn cn li trong hu ht cc chng trnh. Tt c cc h iu hnh ca my tnh c thit k sinh ra cc thng ip bo li (trn mn biu din, hoc trong mt tp tin hng) vo bt c lc nom mt li c pht hin, n bo rng li xy ra v cc kh nng d on nguyn nhn gyli.

Cc li c th c nhm thnh vi dng. Li v c php gy ra do vic s dng dng ngn nglp trnh khng chnh xc. Li v s hp l l sai st trong khi lp trnh. Li do thc hin gy ra dos kt hp ca cc d liu m ngi lp trnh khng liu trc. Mt li do vn hnh tiu biu gyra do vic c gng chia mt s cho s 0. Cc my tnh c thit k lm vic vi mt tp hp,cc s trong mt mc chnh xc c cho trc. Nhiu li b gy ra do s gii hn ny. Mt livt gii hn xut hin khi s qu ln my tnh x l vi n; St li do lm trn s b gy ra dos cn thit phi lm trn s mt s thp phn.

S khm ph li

K thut cung cp mt chng trnh pht hin cc d liu khng ng. Phng php thnggp l thm mt ch s kim tra vo mt m quan trng, nh cc s m v cc mt m tothnh. Ch s c chn sao cho mt m ph hp vi quy tt rng chng trnh c th thay i.Mt k thut khc lin quan n vic tnh tng ca mi trng hp ca chi tit ring ca d liu,v lu tr n to ni kt thc ca d liu. S pht trin li cng c dng trong vic truyn dliu bng cch dng cc modem.

Thng bo li

Thng bo c my tnh to ra bo cho ngi s dng bit rng c mt li xut hin.

Tp tin kh thi

Tp tin, lun l mt chng trnh ca mt s dng, n c th c thc hin trc tip bi mt mytnh. Tp tin s c sinh ra t chng trnh ngun bi mt b phn lp rp hay thu thp tin. Vth n s khng c m ha trong ASCII v s khng th c c nh mt vn bn trn hMS-DOS cc tp tin thc hin c c phn m rng .EXE hay .COM

Li thc hin

Li b gy ra do s kt hp ca cc d liu m ngi lp trnh khng d on trc.

B nh m rng

B nh ph trong my tnh da trn MS-DOS, thng c lp trn mt bn b nh m rng. B

nh m rng i hi mt b phn qun l n nhm to s tip cn ti s b nh gii hn ti mt


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thi im bt k, v n chm hn b nh ph. Phn mm c th chy c MS-DOS v Windows m phng b nh m rng cho nhng ng dng i hi n.

Bn m rng

Bn mch in m c th c gi vo my tnh tng cng cc kh nng ca chng (v d nhtng b nh ca chng) hoc thm cc phng tin (v d nh hnh nh)

H thng chuyn gia

Chng trnh my tnh a ra li khuyn (nh cc d on s suy yu hay gii thch cc lut)m kt hp kin thc t nhng tinh hoa ca con ngi. N l mt dng ca h thng da trn cs kin thc cha cc quy lut m c th c p dng tm li gii cho mt vn . N l mtdng ca tr thng minh nhn to.

Xut

U RA CA MT TP TIN TRONG DNG KHC M T n c s dng bi cc ngdng hin hnh. V d nh chng trnh x l t chy trn my tnh kiu Apple Macintosh c thc phng tin lu tr mt tp tin trn a mm trong dng c th c c bi chng trnhx l t chy trn my tnh c nhn IBM.

B nh m rng

B nh trong h da trn MS-DOS trn mt byte m DOS tr gip. B nh m rng khng thhiu c h iu hnh v n i hi b phn qun l b nh m rng. Windows v cc ng dngca Windows i hi c b nh ph

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