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Preparing the NXT Brick

Nowthatafunctionalprogramhasbeencreated,itmustbetransferredtotheNXTBrickandthenrun.ThisisaperfecttimetotakealookattheNXTBrickindetail.

The NXT Brick

TheNXTBrickisthebrainofaLEGO®MINDSTORMS®robot.Itboastsapowerful32-bitmicroprocessorandflashmemory.

TheNXTcanreceiveinputfromuptofoursensorsandcontroluptothreeNXTorseveralTETRIX®DCandservomotors,allviaitssevenports.ItalsohasanLCDdisplayandfourbuttons.ThebuttonsareusedtonavigatethroughtheNXTmenus.TheNXTispoweredbysixAAbatteriesorarechargeablebatterypack.

ThetwograyarrowbuttonsareusedtonavigatethroughtheNXT’smenus.Theorangebuttonisusedtoselectobjectsfromthemenu,andthedarkgrayrectanglebuttonisusedtoendaprogramornavigatetothemainmenuontheNXT.

ProgramscanbetransferredfromacomputertotheNXTusingUSBorBluetooth®.

Using a USB Cable:

IfaUSBcableisbeingusedtoconnect:

1.ConnectoneendoftheUSBcabletotheNXTBrick.

2.ConnecttheotherendoftheUSBcabletothecomputer’sUSBport.

Note: ItisimportanttobepatientastheoperatingsystemcantakeafewminutestoinstallthedriversthefirsttimeanNXTisconnectedtothecomputer,

Using Bluetooth:

IfBluetoothisbeingusedtoconnect:

1.EnsurethatBluetoothisenabledontheNXT.Todothis,turnontheNXTandselectBluetoothfromthemainmenu.

2.EnsurethatBluetoothisturnedonbyselectingtheOn/OfficonandselectingOn.OnceBluetoothisturnedon,theNXTwillreturntothemainmenuwhereBluetoothmustbeselectedagain.

3.EnsurethattheNXT’svisibilityisenabledsothatthecomputerisabletoseeit.Todothis,gointotheBluetoothmenuagain,selectVisibility,andthenselectVisible.

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Connecting to the NXT using ROBOTC®

GotoLink SetupunderNXT BrickintheRobottab.Thiswillopenawindowsimilartotheoneshownbelow.

a.UsingUSBwithROBOTC

1.IftheNXTisalreadyconnectedviaUSB,itwillbelistedunderNXT Bricks Currently Connected via USB.

2.ClickitoncetohighlightitandclicktheSelectbuttontolinkittoROBOTC.

3.ClickClosetoclosethewindow.

b.UsingBluetooth®withROBOTC

1.IfBluetoothisbeingusedandtheNXTdoesnotshowupintheboxbelowNXTBricksReachableviaBluetoothWireless,selectInclude Bluetooth intheBrick SearchoptionandclicktheRefresh Listsbutton.

2.OncetheNXTisvisible,clickitoncetohighlightitandclicktheSelect via BTbuttontolinkittoROBOTC.ApromptwillappeartoenterapasskeyintotheNXTBrick.Thedefaultshouldbe1234.Ifitisnot,usethegreyarrowkeysandtheorangeselectbuttonontheNXTBricktoenterit.Selectthecheckmarktoselectthepasskey.

3.NowclicktheClosebuttononthecomputertoclosethewindow.

OncetheNXTisconnected,programscanbedownloadedbyselectingCompile and Download ProgramundertheRobottaborbypressingF5.

Toruntheprogram,selectStartintheProgram DebugwindowthatappearsinROBOTCorfindthefileontheNXTandselectRun.

TheNXThasnowbeensuccessfullyconnectedtothecomputerandprogramshavebeendownloadedandrun.

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Connecting to the NXT using LabVIEW™ for LEGO® MINDSTORMS®

TellLabVIEWforLEGOMINDSTORMShowtofindtheNXT.

Using a USB with LabVIEW

1.IfaUSBcableisbeingused,clicktheConnect to an NXTdrop-downmenuontheRobot Project CenterwindowandclickFind NXT.

Note:BecausetheNXTisalreadyconnectedviaUSB,itwillbelisted.ClickitoncetohighlightitandclickConnecttolinkittoLabVIEW.

2.Thewindowisupdatedtoshowthename,batterylevel,andotherinformationaboutthebrickthatisconnected.

Using Bluetooth® with LabVIEW for LEGO MINDSTORMS

Note: ToconnecttotheNXTviaBluetooth,ensurethateitherthecomputerhasbuilt-inBluetoothcapabilitiesorthataUSBBluetoothadapterhasbeeninstalled.EnableBluetoothfromacomputeroraBluetoothadapter.

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NowthatBluetooth®isactiveonthecomputerandtheNXT,connecttotheNXTviaBluetooth®.

1.ToconnecttotheNXT,clicktheConnect to an NXTdrop-downmenuontheRobot Project CenterwindowandclickFind NXT.

2.ClickScantosearchforBluetoothdevicesandnoticethatLabVIEWforLEGO®MINDSTORMS®issearchingforBluetoothdevices.

3.Afterabout10-15seconds,theNXTwillbefound.

4.ClickonceonthenameoftheNXTtohighlightitandthenclickConnect.

Note: IfthisisthefirsttimethisNXTisconnectingtoacomputer,apromptwillappeartoenterapasskeybeforetheNXTcanpairwiththecomputer.

5.Enter“1234”asthepasskeyandselectOK.AbeepwillbeheardandapromptwillappearontheNXTBricktoenteraPIN.Select“1234”bynavigatingrightandleftwiththegrayarrowbuttonsonthebrickandselectingwiththeorangebutton.

6.Once“1234”hasbeenentered,navigatetothecheckmarkiconandpresstheorangebutton.

7.Oncethisiscomplete,theoperatingsystemwilltakeafewmomentstoformaconnectiontotheNXTviaBluetooth®.ItwillnowbepossibletowirelesslycompileprogramsontotheNXT.

Note: ManyotheroptionsoftheNXTcanbeexploredusingLabVIEWforLEGOMINDSTORMSviatheNXTTerminal.

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The NXT Terminal

AccesstheNXTTerminalbyselectingNXT TerminalfromtheToolsmenuandthenselectingNXT Terminal.

IftherearemultipleNXTsconnected,selectwhichonetocommunicatewithbyusingthedrop-downmenu.Thiswindowshows:

•ThebatteryleveloftheNXT•Theamountoffreespaceinitsmemory•Itsfirmwareversion

Note:ThefirsttimeanNXTBrickisrunwithLabVIEW™forLEGO®MINDSTORMS®,makesuretoupdatethefirmwarebyclickingUpdate Firmware.ThisshouldonlybedonewhenconnectedviaUSB.

•Atthebottomofthiswindow,theFileOperationswillbevisible.AllofthefilescurrentlyontheNXTwillappear.ItisagoodideatodeleteanyoldprogramsfromtheNXTthatwillnotbeusedanymore.Allofthesoftwarefilesarein“.rxe”format.ClickthefileoncetohighlightitandthenclicktheDelete File(s) buttontoremoveit.

•TheDefragmentbuttoncanalsobeclickedtoclearupsomememory.

NowprogramscanberunontheNXT.LookattheLabVIEWtoolbar.Noticethattherearethreebuttonstorunaprogram,eachofwhichrunstheprogramslightlydifferently.ThesethreebuttonsareRun,Deploy,andDebug.

•TheRunbuttoncompilestheprogramontotheNXTandimmediatelyrunsit.Ifthisisdonewiththecodecreatedinthelessontomaketherobotmoveforward,LabVIEWforLEGOMINDSTORMScompilesthesoftwareontotheNXTandtherobotimmediatelymovesforward.

•TheDeploybuttoncompilesanddownloadstheprogramontotheNXTbutdoesnotrunituntilthebuttonsontheNXTBrickhavebeenusedtochooseit.ThisisveryhelpfulwhencompilingprogramsusingUSBwithoutrunningtheprogramimmediately.Forexample,iftheprograminvolvestherobotmoving,theRun buttonwillcompileandruntheprogram,causingtherobottostartmovingwiththeUSBcablestillattached.TheDeploybuttonwillonlycompiletheprogram.TheUSBcablemustberemovedtorunit.

•ThethirdmethodforrunningaprogramistheDebug option.Essentially,DebugkeepsthelinkbetweentheLabVIEWprogramonthecomputerandtheNXTBrick.Usethistodebugtheprogramandinterrogateittomakesureitisworkingproperly.

SelecteithertheRunbuttonortheDeploybutton.Arobotprogramhasnowbeencreatedanddeployed.

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