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5.4 DATA BUSES

1

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BITS, BYTES,WORD

T! tra"#t#o$al "ata #!rarc% ar!& B#t ' !#t!r ( or 1

B%t!s ' a coll!ct#o$ o) b#ts to ma*! acaract!r

Wor" ' a coll!ct#o$ o) b%t!s to a+! am!a$#$g)l wor".

-#!l" ' a coll!ct#o$ o) wor"s

A r!cor" ' a coll!ct#o$s o) !l" o$ ar!lat!" sb/!ct.

0

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Tra"#t#o$al Eampl! ' STUDE2TS

-I3E

St"!$ts -#l! ' co$s#st o) 1(( r!cor"s o)st"!$t.

A r!cor" ' )or !ampl! ' #$)ormat#o$ o$ a

st"!$t. -#!l"s ' !ampl! st"!$ts $am! or a""r!ss

or t!l!po$! $mb!r !.g Abraam aslow

Wor" ' t! $am! o) a st"!$t !.g Abraam B%t!s ' !.g A #s r!pr!s!$t!" b% 1((((((1

B#t ' !#t!r ( or 1

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ARI27 408 DATA WORD

I$ compt#$g, word#s t! $atral $#t o)"ata s!" b% apart#clar proc!ssor "!s#g$.

It #s bas#call% a !" s#:!" gropo) b#ts tat ar! a$"l!" as a $#t b%t! #$strct#o$

T! $mb!r o) b#ts #$ a wor" ;t! wordsize, word width, or word length< #s"!t!rm#$!" b% t! compt!r arc#t!ctr!.

4

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I2TRODU7TIO2 TO DATABUSES

Data bs!s ar! s!" to tra$sm#t "ata)rom o$! compo$!$t to a$ot!r.

T! bs!s ca$ b! !l!ctr#cal or br!opt#c.

T! sp!c#cat#o$ )or "atatra$sm#ss#o$ #s "raw$ b% ARI27.

T! sta$"ar" s!" #$ a#rcra)ts #s t!ARI27 408.

5

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ABOUT ARI27 408

It "!$!s ow a+#o$#cs !=#pm!$t sol" tal*w#t !ac ot!r.

D!$!s t! !l!ctr#cal a$" "ata caract!r#st#csa$" protocol.

A 0 b#ts s!r#al bs w#t "ata >ow #$ o$!"#r!ct#o$. I) two "#r!ct#o$s ar! r!=#r!", t!$ twos!ts o) bs!s ar! r!=#r!". ;ma 0( r!c!#+!rsow

a 1((*b

R!c!#+!r ma 0(

Sar!" bs!s ' ma 10(

Two wa%s

a 0 m!ga

R!c!#+!r ' ma 10(

00

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ARI27 608 ESSAHESTRU7TURE

0

!ssag!

a 1 wor"str#$g

gap 4 b#ts

Eac lab!l0(b#tslab!l?10!t?4 s%$cro1

par#t%

Eac "ata wor"0(b#ts 16 "ata s%$ 1

par#t%

Eac wor" str#$g3ab!l @ 056 "atawor"s

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ESSAHE STRU7TURE

04