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2015 HIGHER SCHOOL CERTIFICATE EXAMINATION
1110
Software Design and Development
General Instructions
•Readingtime–5minutes
•Workingtime–3hours
•Writeusingblackpen
•Drawdiagramsusingpencil
•WriteyourCentreNumberandStudentNumberatthetopofeitherpages29and31orpages35and39
Total marks – 100
Section I Pages2–9
20 marks
•AttemptQuestions1–20
•Allowabout35minutesforthissection
Section II Pages13–28
60 marks
•AttemptQuestions21–32
•Allowabout1hourand50minutesforthissection
Section III Pages29–40
20 marks
•AttempteitherQuestion33orQuestion34
•Allowabout35minutesforthissection
–2–
Section I
20 marksAttempt Questions 1–20Allow about 35 minutes for this section
Usethemultiple-choiceanswersheetforQuestions1–20.
1 Ateamhasbeencontractedtocreateasoftwarepackage.
Whichofthefollowingistheteam’smostappropriatefirststep?
(A) UseaGanttcharttoplanthedevelopment
(B) Lookforusefulmodulesinasoftwarelibrary
(C) Interviewtheclientforthesystemrequirements
(D) Createaprototypetoshowdifferentinterfacestyles
2 Acouncilwebsiteisbeingdevelopedtoallowresidentstonominateonedayoftheweekforgarbagecollection,andtoselectabinfromoneofthreesizes.
Whichcombinationofscreenelementswouldbebestforcapturingtheresidents’choicesofcollectiondayandbinsize?
Collection day Bin size
(A) Drop-downlist Radiobuttons
(B) Drop-downlist Checkboxes
(C) Textbox Radiobuttons
(D) Textbox Checkboxes
3 Whichofthefollowingisrepresentedinadataflowdiagram?
(A) Theorderinwhichprocessesoccur
(B) Wheredataoriginatesandwhereitisstored
(C) Thesequenceoftasksinvolvedincompletingaproject
(D) Thedecisionsthataremadewhensub-modulesarecalled
–3–
4 Itislegaltocopysoftwareandsellthecopiesif
(A) copyrightisacknowledged.
(B) thesoftwareisopensource.
(C) thesoftwarehasbeenpaidfor.
(D) thelicencespecifiesthatthisisallowed.
5 Someofthevariablesinaprogramaretobegivennewnames.
Whichdocumentationmustalsobemodified?
(A) Storyboard
(B) Datadictionary
(C) Systemflowchart
(D) Requirementsdefinition
6 Considerthisalgorithm.
BEGIN
N = 20
CASEWHERE N is
less than 10 : N = N + 5
less than 30 : N = N + 10
less than 50 : N = N + 30
OTHERWISE : N = N + 50
ENDCASE
Display N
END
Whatistheoutputofthealgorithm?
(A) 70
(B) 60
(C) 30
(D) 25
–4–
7 Howcantheinclusivityofacomputerprogrambeenhanced?
(A) Byreplacingpasswordcharacterswithasterisks
(B) Byprovidingarangeofmethodsforinputtingdata
(C) ByprovidingallthenecessarylibraryroutinesinasingleDLL
(D) Byensuringthatallsourceshavebeenincludedintheacknowledgements
8 Whichofthefollowingisusuallyabenefitofusingthepilotmethodofinstallation?
(A) Thedevelopmenttimeisreduced.
(B) Abackupofdataiscreatedforeachnewtransaction.
(C) Thepersonnelinvolvedcanbeavailabletotrainothers.
(D) CASEtoolscanbemoreeffectivelyused.
9 Whichrowofthetablebestmatchesthedataitemwithasuitabledatatype?
Data Item Data Type
(A) Atelephonenumber Boolean
(B) Onestudent’spersonaldetails Real
(C) Thestatusofaradiobutton Boolean
(D) Alistofwinninglotterynumbers Real
10 Whichrowofthetablecorrectlymatchesdocumentationwithitspurpose?
Documentation Purpose
(A) Logbook Recordingprogressandproblemsencounteredduringsoftwaredevelopment
(B) Storyboard Showingthelinksbetweenhardwaredevicesandthedatabeingprocessed
(C) IPOchart Testingthesystemforlogicerrors
(D) Benchmarkreport Showingtheorderofexecutionofprogrammodules
–5–
UsethefollowingalgorithmtoanswerQuestions11and12.
BEGIN
low = 1
END
high = n
n = number of elements in the array list
list(low) = list(high)
list(high) = list(low)
low = low + 1
high = high – 1
islow < n?
No
Yes
11 Whichofthefollowingcontrolstructuresisusedintheflowchart?
(A) Binaryselection
(B) Pre-testrepetition
(C) Post-testrepetition
(D) Multiwayselection
12 Originallythearraycalledlistcontainsfivenumbers.
1 3 5 7 9
Whatwilllistcontainafterthealgorithmisexecuted?
(A) 1 3 5 3 1
(B) 1 3 5 7 9
(C) 9 7 5 3 1
(D) 9 7 5 7 9
–6–
13 Whatistheroleoftheprogramcounter?
(A) Itstorestheaddressofthenextinstruction.
(B) Itcountsthenumberoftimesaloopisexecutedinaprogram.
(C) Itkeepstrackofthelinenumberinthesourcecodeasitisbeingtranslated.
(D) Itstoresthenumberofuserspermittedtosimultaneouslyaccessaprogram.
14 MoveMeisdefinedbythefollowingrailroaddiagram.
MoveMe
AngleLength
Move
WhichofthefollowingEBNFstatementsisacorrectrepresentationofMoveMe?
(A) MoveMe = Move { <Angle> <Length> }
(B) MoveMe = Move [ <Angle> <Length> ]
(C) MoveMe = Move { <Length> <Angle> }
(D) MoveMe = Move [ <Length> <Angle> ]
15 Adeveloperappliesreverseengineeringtoapieceofsoftware.
Whatisthedevelopertryingtoachieve?
(A) Toreverttoapreviousversion
(B) Toretrievetheoriginalsourcecode
(C) Tounderstandhowthesoftwareworks
(D) Toensurecompatibilitywitholderversions
–7–
16 The following algorithm is designed to allow theuser up to three attempts to enter acorrectpassword.
1 BEGIN
2 Count = 1
3 Flag = False
4 WHILE . . . . . . . . . . . . . . . . . .
5 GetPassword(PasswordAttempt)
6 IF PasswordAttempt is correct THEN
7 Flag = True
8 Display “Enter”
9 ELSE
10 Display “Incorrect”
11 Count = Count + 1
12 ENDIF
13 ENDWHILE
14 END
Whichofthefollowingcorrectlycompletesline4?
(A) Count < 3 OR Flag = True
(B) Count < 4 OR Flag = True
(C) Count < 3 AND Flag = False
(D) Count < 4 AND Flag = False
17 Anarraywasoriginally
4 5 10 7 7 .
Afteronepassofasort,thearraybecame
4 5 7 7 10 .
InwhichofthefollowingareALLthesortingmethodslistedcapableofproducingthisresult?
(A) Bubble,insertion
(B) Bubble,selection
(C) Insertion,selection
(D) Bubble,insertion,selection
–8–
18 Considerthefollowingalgorithm.
BEGIN
number = 5
WHILE number < 200
Display number
Increment number by 2
ENDWHILE
END
Whichofthefollowingalgorithmswillproducethesameoutput?
(A) BEGIN
REPEAT
Display number
number = number + 2
UNTIL number > 200
END
(B) BEGIN
FOR number = 2 to 100
Display number * 2 + 1
NEXT number
END
(C) BEGIN
number = 5
REPEAT
Display number
Increment number by 2
UNTIL number = 200
END
(D) BEGIN
FOR number = 5 TO 200 STEP 2
Display number
NEXT number
END
19 Afteranarrayissorted,itselementsappearinthefollowingorder.
–10 100.78 7.8 71
Whattype(s)ofdatadoesthearraycontain?
(A) Real
(B) String
(C) Realandinteger
(D) Stringandinteger
–9–
20 Diff(a, b, result)isasubroutinethatacceptstwonumbersasinput.Itreturns“yes”inresultifthedifferencebetweenthenumbersislessthan10.Otherwiseitreturns“no”.
Whichofthefollowingcodefragmentswouldbemostusefulfortestingthesubroutinewitharangeofvalues?
(A)
REPEAT
input a
input b
Diff(a, b, result)
UNTIL result = “yes”
(B)
result = “no”
input a
input b
IF b – a < 10 OR a – b < 10 THEN
result = “yes”
ENDIF
Display result
(C)
FOR x = 1 TO 100
input a
input b
Diff(a, b, result)
NEXT x
Display result
(D)
input again
WHILE again ≠ “no”
input a
input b
Diff(a, b, result)
Display result
input again
ENDWHILE
BLANK PAGE
–10–
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–11–
BLANK PAGE
© 2015 Board of Studies, Teaching and Educational Standards NSW©2015BoardofStudies,TeachingandEducationalStandardsNSW
–12–
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Centre Number
Student Number
–13–
43933103511111 15360
2015 HIGHER SCHOOL CERTIFICATE EXAMINATION
Software Design and Development
Section II
60 marksAttempt Questions 21–32Allow about 1 hour and 50 minutes for this section
Answer the questions in the spacesprovided. These spaces provideguidance for the expected length ofresponse.
If you include diagrams in youranswer, ensure that they are clearlylabelled.
Extra writing space is provided onpages27and28.Ifyouusethisspace,clearly indicate which question youareanswering.
Write your Centre Number andStudent Number at the top of thispage.
Please turn over
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2381310356
Question 21 (2marks)
OutlineTWOreasonsformaintainingsoftware. 2
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Question 22(4marks)
Describehowacompletedprogramcouldbetestedbeforeitisreleased. 4
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Question 23(7marks)
(a) Whatinformationaboutalibraryroutineshouldbedocumentedtoenableitsusebyotherprogrammers?
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(b) The subroutine CharTally(String, Char, Count) counts the number of times acharacter(Char)appearsinStringandreturnstheresultinCount.
Aone-dimensionalarraycalledStudentscontains20names.
Writeanalgorithmtocountthetotalnumberoftimesthatthelower-caseletter‘ f ’appearsinthearrayStudents.UsethesubroutineCharTallyinyouralgorithm.
4
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4873310354
Question 24(3marks)
Usingexamples,distinguishbetweentheeffectsofruntimeerrorsandlogicerrors. 3
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Question 25(3marks)
Explainwhysoftwaredevelopersmayprovidefreeupdatesforpurchasedsoftware. 3
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Question 26(4marks)
Aclubhas200members.
Each member’s information is contained in an unsorted array of records calledMembers.TheIDforeachmemberisunique.
The following algorithm displays the name of a member after the member’s ID isentered.
BEGIN
Get MemberID
FOR Counter = 1 to 200
IF MemberID = Members(Counter).ID THEN
Display Members(Counter).Name
ENDIF
NEXT Counter
END
Rewritethealgorithmsothat:
• itdisplays‘Invalid ID’iftheIDenteredisnotfound
• thelinearsearchterminatesassoonasamember’snamehasbeendisplayed.
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9964310350
Question 27(3marks)
Softwareapplicationsarenowcreatedtorunonarangeofportabledevices,suchas 3smartphonesandtablets,aswellasarangeofdesktopcomputers.
Outlinehowthisaffectssoftwaredevelopment.
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Question 28(7marks)
AchainofvideostoresisintroducinganATM-stylekioskthatwillenablecustomerstocopymoviestotheirownUSBdevices.
Thekioskwillprovidemovieinformation,enablepaymentandallowdownloadtoaUSBdevice.
(a) Discussthesuitabilityofboththeprototypingandrapidapplicationdevelopmentapproachesfordevelopingthissystem.
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–19–
5638310354
Question28(continued)
(b) Thekioskinterfacewillincludethefollowingfeatures:
• asearchoption
• alistofmoviesresultingfromasearch
• abilitytochoosetoseedetailsofaselectedmovie
• paymentanddownloadinstructions.
Astoryboardisbeingproducedtorepresenthowthekioskinterfacewilloperate.Thefirstscreenofthestoryboardisshownbelow.
Completethestoryboard.Notethatwithineachscreenthereneedonlybeatitleandnecessarybuttons.
Search movies
SEARCH screen
End of Question 28
3
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–20–
9657310359
Question 29(9marks)
A program is required to operate an online shopping service. The following algorithm waswrittenbyadeveloperatanearlystageofdevelopment.
BEGIN Main VegPrice = 0 MeatPrice = 0 Display menu Input MenuChoice WHILE MenuChoice is not “Finish” CASEWHERE MenuChoice is “Vegies” : Veg (VegPrice) “Meat” : Meat (MeatPrice) ENDCASE Display menu Input MenuChoice ENDWHILE ShowTotal (VegPrice, MeatPrice, Total)END Main
BEGIN Veg (VegPrice) Display “Veg module called” VegPrice = 10END
BEGIN Meat (MeatPrice) Display “Meat module called” MeatPrice = 20END
BEGIN ShowTotal (VegPrice, MeatPrice, Total) Total = VegPrice + MeatPrice Display VegPrice, MeatPrice, Total get confirmation IF confirmation = True THEN Pay (Total) ELSE Clear ENDIFEND
BEGIN Pay (Total) Display “Pay module called” Display TotalEND
BEGIN Clear Display “Clear module called”END
Question 29 continues on page 21
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6157310351
Question29(continued)
(a) WhatpurposedoestheMainmodulehavefortheuser?
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2
(b) ThealgorithmcontainsthestubsVeg,Meat,PayandClear.
Explainthepurposeofthesestubsindevelopingthisprogram.
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(c) Drawastructurechartcorrespondingtothealgorithmshown. 4
End of Question 29
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1086310357
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6784310357
Question 30(5marks)
A car dealership maintains information about all the cars that it has for sale. Theinformationabouteachcarincludes:
• ID
• Make
• Model
• Manual/Auto
• Price
• Yearofmanufacture.
Adeveloperisrequiredtowriteaprogramwhich:
• maintainsrecordsofcarsboughtandsold
• enablesdealerstosearchforcarsthatmeetdifferentspecifications.
(a) Whyisanarrayofrecordsappropriateformanipulatingthisdata?
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(b) Discusswhetherthedatainthearrayofrecordsshouldbesorted. 3
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7927310357
Question 31(9marks)
Validserialnumbersforadevicemustbe:
• 5charactersinlength
• startwitha#symbol
• contain3digits
• endwitha#symbol.
Forexample,#123#isavalidserialnumber.
Thefollowingalgorithmwasdesignedtocheckifagivenserialnumberisvalid.
1 BEGIN
2 Input SerialNumber and store the characters in the array of characters called Serial
3 Valid = False
4 IF (Length of SerialNumber = 5) AND (Serial(1) is “#”) THEN
5 FOR Counter = 2 to 5
6 IF Serial(Counter) is a digit THEN
7 Valid = True
8 ELSE
9 Valid = False
10 ENDIF
11 NEXT Counter
12 ENDIF
13 IF Serial(5) is not “#” THEN
14 Valid = False
15 ENDIF
16 Display Valid
17 END
(a) Deskcheckthealgorithmusingtheserialnumber#1k3#asinput. 3
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–25–
9403310358
Question31(continued)
(b) Thealgorithmcontainserrors.Showhowthealgorithmshouldbemodifiedtocorrecttheerrors.
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(c) List testdatanecessarytotest thelogicof thealgorithm.Justifyeachiteminyourlist.
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8246310352
Question 32(4marks)
A computer game based on cards numbered from 1 to 28 is to be developed. The28cardsarestoredrandomlyinanarraycalledCards.Anexampleisshown.
4
Cards
8 1 7 5 11 … … … 12 26 13 19 14 22
Therearefourplayersandeachplayerisdealtsevencards.Anarrayisassignedtoeachplayerforstoringtheircards.TheplayersaregivencardsfromthearrayCardsonecardatatimestartingwithPlayer 1,thenPlayer 2,Player 3,Player 4,andthenbacktoPlayer 1,Player 2,Player 3,Player 4andsoon.
Examplesoftheplayers’arraysareshown.
Player 1
8 11 4 3 17 27 13
Player 2
1 9 2 10 20 28 19
Player 3
7 21 16 15 25 12 14
Player 4
5 18 23 6 24 26 22
WriteasubroutinecalledDealCardstodistributethecardsfromthearrayCardstoeachofthefourplayers.Inyouralgorithm,includeappropriatecontrolanddatastructures.
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9248310355
Section II extra writing space
If you use this space, clearly indicate which question you are answering.
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–28–
8455310354
Section II extra writing space
If you use this space, clearly indicate which question you are answering.
©2015BoardofStudies,TeachingandEducationalStandardsNSW
–29–
Centre Number
Student Number
83293100401112 15360
2015 HIGHER SCHOOL CERTIFICATE EXAMINATION
Software Design and Development
Section III
20 marksAttempt either Question 33 or Question 34Allow about 35 minutes for this section
Answerthequestioninthespacesprovided.Thesespacesprovideguidancefortheexpectedlengthofresponse.
Ifyouincludediagramsinyouranswer,ensurethattheyareclearlylabelled.
Question 33 — Programming Paradigms (20marks)
(a) An e-learning application, composed of various types of activities, is to bedeveloped.
Eachtypeofactivitywillhave:
• auserinterfacespecification
• prerequisiteconditionsthatstudentsmustmeetbeforetheycanuseit.
Whenanactivityiscompleted,theapplicationsuggestsfurtheractivitiesbasedonthestudent’sinterestsandhowwellthestudentcompletedtheactivity.
Discussthesuitabilityofthelogicparadigmandtheobjectorientedparadigmfordevelopingthisapplication.
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–30–
3146310042
Question33(continued)
(b) Usinganexample,outlinewhyheuristicsareusedinsomesoftwaresolutions.
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(c) Thisisafragmentoflogicparadigmcode,with
• salary(P,S) definedas‘thesalaryofpersonPisamountS’
• employer(P,E) definedas‘theemployerofpersonPisemployerE’.
salary(kim,56000).
salary(chris,23000).
salary(jay,46000).
salary(al,51000).
salary(jo,61000).
employer(chris,kim).
employer(kim,jay).
employer(al,jay).
employer(sam,jay).
valuable_employee(X):- employer(X,_) , salary(X,S) , S > 50000.
(i) Extendthefragmentofcode,usingfactsonly,sothatLingisavaluableemployee.
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(ii) Evaluatevaluable_employee(E)?.Showreasoning.
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Question 33 continues on page 31
©2015BoardofStudies,TeachingandEducationalStandardsNSW
–31–
CentreNumber
StudentNumber
2015 HIGHER SCHOOL CERTIFICATE EXAMINATION
Software Design and Development
Section III (continued)
5499310056153601113
Question33(continued)
Please turn over
–32–
Question33(continued)
(d) Acustomcarmanufacturermakescarstoorderbasedoncustomers’selectionsofcomponents.Eachcomponentmaybestandardorspecialised.
The cost of a car is calculated by totalling the costs of all components. Thecostofeachstandardcomponentisfixed.Thecostofaspecialisedcomponentiscalculatedbyaddingthecostofthespecialisationtothecostofthestandardcomponent.
Thesoftwaretomanagecustomers’selectionsisbeingdeveloped.Thisfragmentofcodehasbeendesignedtobepartofthesoftware.
class Car {
private –
components: array of Component
public –
cost():
sum = 0
FOR i = 1 TO number of components
sum = sum + components[i].cost()
NEXT i
return sum
}
class Component {
public –
cost(): REM returns the cost of the component
}
(i) Explain how polymorphism AND inheritance can be used in thedevelopmentofthissoftware.
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Question33(continued)
(ii) Astandardenginecosts$2000,butaV8enginecostsanextra$800.
Writethecost()methodtocalculatethecostofinstancesofthefollowingsubclassesofComponent.
class Engine {
is a Component
}
class V8Engine {
is a Engine
}
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Question 33 continues on page 34
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Question33(continued)
(e) The following fragment of code from the object oriented paradigm wasdeveloped to declare an array that alwayskeeps all its items in sortedorder,whennumbersareaddedorremoved.
Themethodsadd()andremove()alwayscallthemethodsort().Themethodsort()callsthemethodswap().
class SortedArray {
private –
items: array of integer
size: integer
public –
sort():
swap(index1, index2):
tmp = items(index1)
items(index1) = items(index2)
items(index2) = tmp
add(number):
remove(index):
}
Thecodecontainsanerror.
Explaintheconsequencesoftheerrorandshowhowitcanbecorrected.
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End of Question 33
©2015BoardofStudies,TeachingandEducationalStandardsNSW
–35–
CentreNumber
StudentNumber
85433101161114 15360
2015 HIGHER SCHOOL CERTIFICATE EXAMINATION
Software Design and Development
Section III (continued)
Do NOT attempt Question 34 if you have already attempted Question 33.
Question 34 — The Interrelationship between Software and Hardware (20marks)
(a) Perform the calculation of 10111 × 111 using binary arithmetic, showing allnecessaryworking.
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(b) What are the benefits of using 2’s complement to represent integers incomputers?
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Question 34 continues on page 36
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Question34(continued)
(c) Acomputer-controlledcuttingtoolcutsstraightlines.
Datastreamssentfromthecomputertothetoolaremadeupof16-bitpacketswiththefollowingstructure.
1
A BT X
1 0
Y
A: start bits, always 1 1
T: tool setting bit
0 = Tool up (not cutting)
1 = Tool down (cutting)
X: 6 bits specifying the X-coordinate to which the cutter moves
Y: 6 bits specifying the Y-coordinate to which the cutter moves
B: stop bit, always 0
(i) Thefollowingdatastream, inhexadecimalform, issent to thecuttingtool
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D 6 A 0.
Eachhexadecimaldigitrepresents4bitsofthedatastream.
Describewhatthisdatastreamachieves.
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Question 34 continues on page 37
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5123310117
Question34(continued)
(ii) ThecuttingtooliscurrentlyatX = 0, Y = 0.
Writethedatastreamneededtocutthepatternshownbelow.
3
0 15 30 450
15
Y
X
30
45
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Question 34 continues on page 39
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© 2015 Board of Studies, Teaching and Educational Standards NSW
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Centre Number
Student Number
2015 HIGHER SCHOOL CERTIFICATE EXAMINATION
Software Design and Development
Section III (continued)
Question34(continued)
(d) Inbinary,thedecimalfraction7.5is111.1.
InIEEE754singleprecisionfloatingpointrepresentation,thedecimalfraction–7.5is:
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1 10000001 11100000000000000000000
Identify the THREE components of the single precision floating pointrepresentationandoutlinehowtorepresent–7.5inthisnotation.
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Question 34 continues on page 40
8432310089153601115
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Question34(continued)
(e) Acarhasanalarmsystemwhichworksasfollows:
• Analarmwillsoundifthekeyisintheignitionandthedriver’sdoorisopen.
• The alarmwill also sound if thekey is not in the ignitionwhile the lights areon.
Inyouranswerstothequestionsbelow,usethefollowing:
Component 1 0
Key In ignition Not in ignition
Door Open Closed
Lights On Off
Alarm On Off
(i) Drawatruthtableforthisalarmsystem. 3
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(ii) Drawalogiccircuittorepresentthissystem. 3
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©2015BoardofStudies,TeachingandEducationalStandardsNSW