Arduino networking marco schwartz

ArduinoNetworking

TableofContents

ArduinoNetworking

Credits

AbouttheAuthor

AbouttheReviewers

www.PacktPub.com

Supportfiles,eBooks,discountoffers,andmore

Whysubscribe?

FreeaccessforPacktaccountholders

Preface

Whatthisbookcovers

Whatyouneedforthisbook

Whothisbookisfor

Conventions

Readerfeedback

Customersupport

Downloadingtheexamplecode

Errata

Piracy

Questions

1.DiscovertheArduinoEthernetShield

Hardwareandsoftwarerequirements

Hardwareconfiguration

Testingyourconnection

Summary

2.SendingDatatoaWebServer



Sendingdatatoaserver

Logincomingdatainadatabase

Displayingtheresults

Summary

3.DataLoggingStation



LoggingdataonanSDcard

CreatingawebserveronArduino

Plottingthedatalocally

Summary

4.ControllingObjectsfromAnywhere



Testingtherelay

Controllingtherelayremotely

Controllingtherelayfromanywhere

Summary

5.InternetofThingswithXively



CreatingyourXivelyaccount

SendingdatatoXively

Visualizingtherecordeddata

Summary

6.LoggingDatainGoogleDocs



SettingupyourGoogleAccount

CreatingyourTembooaccount

Loggingdatainaspreadsheet

Sendingautomatede-mails

Summary

ArduinoNetworking

ArduinoNetworkingCopyright©2014PacktPublishing

Allrightsreserved.Nopartofthisbookmaybereproduced,storedinaretrievalsystem,ortransmittedinanyformorbyanymeans,withoutthepriorwrittenpermissionofthepublisher,exceptinthecaseofbriefquotationsembeddedincriticalarticlesorreviews.

Everyefforthasbeenmadeinthepreparationofthisbooktoensuretheaccuracyoftheinformationpresented.However,theinformationcontainedinthisbookissoldwithoutwarranty,eitherexpressorimplied.Neithertheauthor,norPacktPublishing,anditsdealersanddistributorswillbeheldliableforanydamagescausedorallegedtobecauseddirectlyorindirectlybythisbook.

PacktPublishinghasendeavoredtoprovidetrademarkinformationaboutallofthecompaniesandproductsmentionedinthisbookbytheappropriateuseofcapitals.However,PacktPublishingcannotguaranteetheaccuracyofthisinformation.

Firstpublished:August2014

Productionreference:1140814

PublishedbyPacktPublishingLtd.

LiveryPlace

35LiveryStreet

BirminghamB32PB,UK.

ISBN978-1-78398-686-6

www.packtpub.com

CoverimagebyPratyushMohanta(<[email protected]>)

http://www.packtpub.com

mailto:[email protected]

CreditsAuthor

MarcoSchwartz

Reviewers

C.M.Banas

RyanDunn

PhillipMayhew

TomO’Connor

KrisjanisRijnieks

CommissioningEditor

PramilaBalan

AcquisitionEditor

HarshaBharwani

ContentDevelopmentEditor

SumeetSawant

TechnicalEditors

KunalAnilGaikwad

SiddhiRane

CopyEditors

MradulaHegde

AdithiShetty

ProjectCoordinator

DanutaJones

Proofreader

AmeeshaGreen

Indexer

RekhaNair

ProductionCoordinator

MelwynD’sa

CoverWork

MelwynD’sa

AbouttheAuthorMarcoSchwartzisanelectricalengineer,entrepreneur,andblogger.HehasaMaster’sdegreeinElectricalEngineeringandComputerSciencefromSUPELECinFrance,andaMaster’sdegreeinMicroengineeringfromEPFLinSwitzerland.

Hehasmorethan5yearsofexperienceworkinginthedomainofelectricalengineering.Hisinterestsgravitatearoundelectronics,homeautomation,theArduinoandtheRaspberryPiplatforms,opensourcehardwareprojects,and3Dprinting.

HerunsseveralwebsitesaroundArduino,includingtheOpenHomeAutomationwebsite(http://www.openhomeautomation.net/),whichisdedicatedtobuildinghomeautomationsystemsusingopensourcehardware.

Hehaswrittenanotherbook,HomeAutomationwithArduino,AmazonDigitalServices,Inc.,whichisaself-publishedKindlebook.HehasalsowrittenabookonhowtobuildInternetofThingsprojectswithArduinocalledInternetofThingswiththeArduinoYun,PacktPublishing.

http://www.openhomeautomation.net/

AbouttheReviewersRyanDunnisasolutionsarchitect,whospecializesinwebtechnologiesandenterprise-leveldeployments.HecurrentlylivesinSouthernKansasCity,KS.

HeholdsaBachelor’sdegreeinComputerSciencefromKansasStateUniversityandaMaster’sdegreeinBusinessAdministrationfromtheUniversityofKansas.Hehasworkedforavarietyoforganizations,withhiscareerspanninganumberofindustries,includinge-commerce,digitalmarketing,SEO,education,security,andmobile.

Hehasbeenworkingwithwebtechnologiesforover10years,andduringthistime,hehasalwaysretainedanagnosticapproachtothetechnology,whichhasresultedinawiderangeofexperience.Asasolutionsarchitect,hemanageseveryaspectofsolutiondeployments,includinganalysis,networkarchitecture,systemarchitecture,creativedesign,anddevelopment.

Ihaveawife,Crystal,andtwochildren.Asaresultoftheirsupport,Ihavebeenabletopursuemypassionfortechnologyandamforevergratefulforalltheirlove.

PhillipMayhewhasaBachelorofSciencedegreeinComputerSciencefromNorthCarolinaStateUniversity.HeisthefounderandmanagingprincipalofRextencyTechnologiesLLC,whichisbasedinStatesville,NorthCarolina.Hisprimaryexpertiseliesinsoftwareapplicationperformancetestingandmonitoring.

TomO’ConnorisanexperiencedsystemsarchitectandDevOpsengineer.HelivesintheWestMidlandsintheUnitedKingdom.Overthelast8years,hehasworkedforawidevarietyofcompanies,frome-commercetovideoeffects,andnowistheownerofthecompanyhefounded,whichprovidessystemsconsultancyforwirelessnetworkdesignandinstallations.

Hewritesatechnicalblogonhiswebsitethatprovidesbothtutorialarticlesandupdatesonwhathe’sbeenworkingon.Hehaswide-reachingskillsandexperiencegatheredoverthelast10yearsofworkingonWindows,Linux,andUnixsystemsformostofthattime,coupledwithrecentexperienceindesigningandbuildinghigh-performancecomputersystems.

HeisalsoanactivememberoftheUKDevOpscommunityaswellasacommunitymoderatoronwww.serverfault.com,wherehedemonstrateshisexpertiseandskillstoawideaudience.

KrisjanisRijnieksisadigitalinteractivemediaprofessionalworkingwithprojectsthatinvolvegraphicdesign,animation,userinterfacedesign,projectionmapping,programming,andelectronics.Theoutcomeofhisprojectsusuallyarewebsites,games,andhardwareprototypesorinteractiveinstallations.Healsorunsworkshopsinthefieldofcreativecodingandprojectionmapping.Oneofhismostinterestingcurrentprojectsisthedevelopmentofanopenframeworksadd-onforprojectionmappingontheRaspberryPi—ofxPiMapper.

HeisalsoanMAstudentattheMediaLabHelsinki(AaltoUniversitySchoolofArts,

http://www.serverfault.com

DesignandArchitecture),andheiscurrentlyworkingonhismasterthesis,whichisrelatedtotheofxPiMapperprojectionmappingsoftwareproject.

KrisjanisrunsasmalldigitalmediacompanyCodeBark(www.codebark.com)withhiscolleague,IrinaSpicaka.Together,theyalsodevelopedaplatformcalledCreativeCodingforLiveAudioandVisuals(www.cc4av.info),whichactsasaplaceholderfordifferenteventsandworkshopsrelatedtoelectronicaudiovisualculture.

HeisalsocollaboratingwiththeFabLab,Berlin,andthisiswherehespendsmostofhistimewheninBerlin.

Cinder–BeginCreativeCoding,PacktPublishing,isthefirstbookthathehasworkedon.It’sanintroductiontoCinder,theC++creativecodingframework,(similartoopenFrameworks)andcontainstutorialstogetyoustartedwithCinderasfastandpainlessaspossible.

http://www.codebark.com

http://www.cc4av.info

www.PacktPub.com

Supportfiles,eBooks,discountoffers,andmoreYoumightwanttovisitwww.PacktPub.comforsupportfilesanddownloadsrelatedtoyourbook.

DidyouknowthatPacktofferseBookversionsofeverybookpublished,withPDFandePubfilesavailable?YoucanupgradetotheeBookversionatwww.PacktPub.comandasaprintbookcustomer,youareentitledtoadiscountontheeBookcopy.Getintouchwithusat<[email protected]>formoredetails.

Atwww.PacktPub.com,youcanalsoreadacollectionoffreetechnicalarticles,signupforarangeoffreenewslettersandreceiveexclusivediscountsandoffersonPacktbooksandeBooks.

http://PacktLib.PacktPub.com

DoyouneedinstantsolutionstoyourITquestions?PacktLibisPackt’sonlinedigitalbooklibrary.Here,youcanaccess,read,andsearchacrossPackt’sentirelibraryofbooks.

http://www.PacktPub.com




http://PacktLib.PacktPub.com

Whysubscribe?FullysearchableacrosseverybookpublishedbyPacktCopyandpaste,print,andbookmarkcontentOndemandandaccessibleviawebbrowser

FreeaccessforPacktaccountholdersIfyouhaveanaccountwithPacktatwww.PacktPub.com,youcanusethistoaccessPacktLibtodayandviewnineentirelyfreebooks.Simplyuseyourlogincredentialsforimmediateaccess.


PrefaceArduinoisanamazingplatformtoquicklycreateexcitingelectronicsprojects.UsingtheArduinoplatform,evennon-expertscanconnectsensors,actuators,anddisplaystogetherandbuildcomplexprojectsthatprovideimmediateapplicationsforeverydaylife.

However,theseprojectsareevenbetterwhentheyareconnected,meaningtheyhavesomewaytocommunicatewithotherdevices,andnotnecessarilywithotherArduinoboards.TherearemanywaystoconnectArduinoprojectstogetherandtootherdevicessuchascomputers:WiFi,XBee,Bluetooth,andEthernet.ThisbookwillfocusentirelyonhowtocreateamazingprojectsusingthislatesttechnologytoconnectArduinoprojects.

UsingEthernethasseveraladvantagesoverwirelesssolutions:itisfast,cheap,andyouwillfindplentyofhelponthesubjectontheInternet.Forme,themostimportantthingisthattheEthernetlibraryforArduinoisverywelldocumented,andcomesbuilt-inwiththeArduinosoftware.It’shardwarecounterpart,theArduinoEthernetshield,isalsoverywellbuiltandwellsupportedbytheArduinocommunity.

Inthisbook,wearegoingtoseehowtousetheEthernetshieldandtheEthernetlibraryviasixexcitingprojects.WearegoingtostartwiththeverybasicsandseehowtoconnecttheEthernetshieldtoyourlocalnetworkandtheWeb.Then,wewillsenddatafromtheEthernetshieldtoaserverlocatedonyourlocalnetwork.Finally,wewillintegratetheEthernetshieldinan“InternetofThings”framework,bybuildingseveralprojectsconnecteddirectlytotheWeb.

WhatthisbookcoversChapter1,DiscovertheArduinoEthernetShield,introducestheArduinoEthernetshieldbyshowingyouhowtosetupeverythingsoyoucaneasilybuildmoreexcitingapplicationsinthenextchapters.WearegoingtoconnecttheEthernetshieldtoyourrouter,andmakesurethatitcanaccesstheWeb.

Chapter2,SendingDatatoaWebServer,explainshowtoconnectatemperatureandhumiditysensortoyourArduinoboardandusetheEthernetshieldtosendthisdatacontinuouslytoawebserverrunningonyourcomputer.Wewillalsoplotthisdatainrealtimeonthewebserversothatyoucanvisualizeitinyourbrowser.

Chapter3,DataLoggingStation,usesthesamehardwareasinthepreviouschapter,butwewillmaketheArduinoEthernetmoreindependent.WewilllogthedatameasuredbytheboardlocallyonanSDcard,andalsocreateawebserverontheEthernetshieldsothatitcanbeaccessedfromanydeviceinyourlocalnetwork.

Chapter4,ControllingObjectsfromAnywhere,covershowtoconnectarelaymoduletoourArduinoandEthernetshieldhardwaresothatitcanbecontrolledviathenetwork.Wearefirstgoingtocontrolthisrelaymodulefromwithinyourlocalnetwork,andthenuseadedicatedservicetobeabletocontrolthisrelayfromanywhere.Asanexample,wearealsogoingtoconnectalamptothisrelaymodule.

Chapter5,InternetofThingswithXively,continueswithcloud-connectedprojectsbyinterfacingtheEthernetshieldwithacloudservicecalledXively.Usingthisservice,wewillbeabletosendthedatameasuredbyourprojecttotheWebandmonitoritinrealtimefromtheXivelywebsite,fromanywhereintheworld.

Chapter6,LoggingDatainGoogleDocs,usesthewebserviceTembootointerfacetheEthernetshieldwithevenmorewebservicessuchasGoogleDocsorGmail.Forexample,wearegoingtomakemeasurementsusingourArduinoboardandautomaticallylogtheseresultsinaGoogleDocsspreadsheet,whichcanbeaccessedfromanywhereintheworld.

WhatyouneedforthisbookYouwillneedseveralhardwareandsoftwarecomponentstomakealltheprojectsfoundinthisbook.Ofcourse,youcanjustreadthedescriptionoftheprojectsandlearnthisway.However,IreallyrecommendactuallydoingtheprojectsyourselftoreallylearnabouthowtousetheArduinoEthernetshieldtobuildexcitingnetworkingapplications.

Thehardwarecomponentsrequiredaredetailedatthebeginningofeachchapter.However,whatyouwillreallyneedforalltheprojectsisanArduinoboard.

AlltheprojectsofthebookarebasedontheArduinoUnoboard:

http://arduino.cc/en/Main/arduinoBoardUno

Foralltheprojectsofthisbook,youwillalsoneedtheArduinoEthernetshield:

http://arduino.cc/en/Main/ArduinoBoardEthernet

Onthesoftwareside,thereissomesoftwarethatwewilluseinallthechaptersofthebook.ThefirstsoftwarethatwewilluseinallthechaptersistheArduinoIDEthatyouneedtoinstall.Youcandownloaditfrom:

http://arduino.cc/en/main/software

TheEthernetlibraryitselfiscontainedwithintheArduinoIDE,soyouwon’tneedtoinstallityourself.Therearealsoseveralexternallibrariesyouwillneed,butthesearedetailedineachchapterwheretheyarenecessary.

Youwillalsoneedawebserverrunningonyourcomputerforsomeoftheprojects.Irecommendusingsoftwarethatintegratesawebserverandadatabase,andthathandlesallthedetailsforyou.

IfyouareworkingonWindows,IrecommendusingEasyPHP:

http://www.easyphp.org/

UnderOSX,IrecommendusingMAMP:

http://www.mamp.info/

ForLinux,youcanfollowtheinstructionsprovidedatthefollowinglinktoinstallawebserver:

http://doc.ubuntu-fr.org/lamp

Makesurethattheserverisrunningatthispoint;wearegoingtouseitinseveralprojectsinthisbook.

http://arduino.cc/en/Main/arduinoBoardUno

http://arduino.cc/en/Main/ArduinoBoardEthernet




http://doc.ubuntu-fr.org/lamp

WhothisbookisforThisbookisforallthosewhoarewillingtobuildexcitingconnectedArduinoprojectsusingtheEthernetshield.Youactuallydon’tneedtoknowtheArduinoplatformbeforehandasalltheprojectswillbeexplainedstepbystepwithclearinstructions.Youalsodon’tneedanypriorknowledgeintheEthernettechnology.Theonlythingyouneedtounderstandistheprojectsfoundinthisbookarejustbasicknowledgeinelectronicsandprogramming.

ThisbookisalsoforelectronichobbyistswhowanttolearnmoreabouttheArduinoplatform.Byexecutingtheprojectsfoundinthisbook,youwilllearnaboutmanypossiblewaystousetheArduinoEthernetshield.YouwillalsolearnhowtoconnectsensorsandactuatorstoArduinoandcontrolthemwithinyourlocalnetwork.

Finally,thisbookisalsoforthosewhoarewillingtolearnmoreabouttheInternetofThingsframeworkusingtheArduinoEthernetshield.Thelastchaptersofthebookarededicatedtobuildingprojectsthatareconnectedtocloudservicesandcanbeaccessedfromanywhereintheworld,simplybyconnectingyourArduinoprojectstoyourInternetrouterviaEthernet.

ConventionsInthisbook,youwillfindanumberofstylesoftextthatdistinguishbetweendifferentkindsofinformation.Herearesomeexamplesofthesestylesandanexplanationoftheirmeaning.

Codewordsintext,databasetablenames,foldernames,filenames,fileextensions,pathnames,dummyURLs,userinput,andTwitterhandlesareshownasfollows:“Inthesetup()functionofthesketch,wewilltrytogetanIPaddressusingDHCP.”

Ablockofcodeissetasfollows:

Stringlog_time=String(day())+"/"+

String(month())+"/"+String(year())+""+

String(hour())+":"+String(minute())+":"+

String(second());

Anycommand-lineinputoroutputiswrittenasfollows:

#192.168.1.103/digital/7/1

Newtermsandimportantwordsareshowninbold.Wordsthatyouseeonthescreen,inmenusordialogboxesforexample,appearinthetextlikethis:“IfyouareusingWindows,youwillfindtheinformationyouneedunderNetworkSettingsinyourControlPanel.”

NoteWarningsorimportantnotesorsomeadditionalinformationappearinaboxlikethis.

TipTipsandtricksappearlikethis.

ReaderfeedbackFeedbackfromourreadersisalwayswelcome.Letusknowwhatyouthinkaboutthisbook—whatyoulikedormayhavedisliked.Readerfeedbackisimportantforustodeveloptitlesthatyoureallygetthemostoutof.

Tosendusgeneralfeedback,simplysendane-mailto<[email protected]>,andmentionthebooktitlethroughthesubjectofyourmessage.

Ifthereisatopicthatyouhaveexpertiseinandyouareinterestedineitherwritingorcontributingtoabook,seeourauthorguideonwww.packtpub.com/authors.


http://www.packtpub.com/authors

CustomersupportNowthatyouaretheproudownerofaPacktbook,wehaveanumberofthingstohelpyoutogetthemostfromyourpurchase.

DownloadingtheexamplecodeYoucandownloadtheexamplecodefilesforallPacktbooksyouhavepurchasedfromyouraccountathttp://www.packtpub.com.Ifyoupurchasedthisbookelsewhere,youcanvisithttp://www.packtpub.com/supportandregistertohavethefilese-maileddirectlytoyou.

Alltheup-to-datecodefortheprojectsofthisbookcanalsobefoundatthefollowingaddress:

https://github.com/openhomeautomation/arduino-networking/


http://www.packtpub.com/support

https://github.com/openhomeautomation/arduino-networking/

ErrataAlthoughwehavetakeneverycaretoensuretheaccuracyofourcontent,mistakesdohappen.Ifyoufindamistakeinoneofourbooks—maybeamistakeinthetextorthecode—wewouldbegratefulifyouwouldreportthistous.Bydoingso,youcansaveotherreadersfromfrustrationandhelpusimprovesubsequentversionsofthisbook.Ifyoufindanyerrata,pleasereportthembyvisitinghttp://www.packtpub.com/support,selectingyourbook,clickingontheerratasubmissionformlink,andenteringthedetailsofyourerrata.Onceyourerrataareverified,yoursubmissionwillbeacceptedandtheerratawillbeuploadedtoourwebsite,oraddedtoanylistofexistingerrata,undertheErratasectionofthattitle.


PiracyPiracyofcopyrightmaterialontheInternetisanongoingproblemacrossallmedia.AtPackt,wetaketheprotectionofourcopyrightandlicensesveryseriously.Ifyoucomeacrossanyillegalcopiesofourworks,inanyform,ontheInternet,pleaseprovideuswiththelocationaddressorwebsitenameimmediatelysothatwecanpursuearemedy.

Pleasecontactusat<[email protected]>withalinktothesuspectedpiratedmaterial.

Weappreciateyourhelpinprotectingourauthors,andourabilitytobringyouvaluablecontent.


QuestionsYoucancontactusat<[email protected]>ifyouarehavingaproblemwithanyaspectofthebook,andwewilldoourbesttoaddressit.


Chapter1.DiscovertheArduinoEthernetShieldInthisfirstchapterofthebook,wewillonlyfocusonthebasicsandgetstartedwiththeArduinoEthernetshield.Inordertobuildmorecomplexprojectsinthenextchaptersofthebook,wefirstneedtobeabsolutelysurethatourshieldisfunctioningcorrectly,anditcanconnecttoourlocalnetworkandtheWeb.

Toensurethis,we’llfirstassemblethehardware,andthenbuildasimpleArduinosketchthatwillconnecttotheWeb,grabatestwebpage,anddisplayitbackinsidetheArduinoSerialMonitor.

Thesewillbethemajortakeawaysofthischapter:

First,we’llmakesurethatyouhavealltherequiredhardwareandsoftwarecomponents.WearealsogoingtoassembletheshieldandtheArduinoUnoboard,andconnecteverythingtoourlocalnetworkviaarouter.Then,wewillwritethesketchthatwillconnectyourshieldtoyourlocalnetworkaswellastheWeb,andthissketchwillgrabatestpagetomakesureyourconnectionisworkingcorrectly.Finally,wearegoingtotestthissketchandmonitorthestatusoftheEthernetshieldontheArduinoSerialMonitor.Fromthisfirsttestoftheshield,we’llbeabletotellwhethertheshieldiscorrectlyconnectedtotheInternetornot.

HardwareandsoftwarerequirementsYoudon’tneedalotofhardwareforthisfirstproject.YouonlyneedanArduinoUnoboard,andofcourse,theArduinoEthernetshield.OtherboardssuchastheArduinoMegawillworkaswellfortheprojectsinthefirstchapterofthebook,butyoumightfacedifficultiesfortheprojectsinthefollowingchaptersinthebook.Therefore,IrecommendthatyouuseanArduinoUnoboardforalltheprojectsofthisbook.

Beforeactuallyassemblingtheshieldwiththeboard,makesuretowritedowntheMACaddressoftheshield,whichiswrittenonthebackoftheshield.Wewillneeditlaterintheprojectwhenwewritethefirstsketch.

ThisisanimageoftheassembledboardandtheEthernetshield:

YouwillalsoneedaUSBBtoUSBAcabletoconnecttheArduinoboardtoyourcomputer,andanEthernetcabletoconnecttheshieldtoarouter.

Onthesoftwareside,allyouneedistheArduinoIDE,whichcanbefoundatthefollowingaddress:


TheEthernetlibraryisincludedbydefaultintheArduinosoftware,soyoudon’tneedtoinstallanyadditionalcomponents.


HardwareconfigurationThehardwareconfigurationinthischapterisreallysimple.Atthispoint,youshouldalreadyhavetheArduinoEthernetshieldconnectedtoyourArduinoUnoboard.Ifthat’snotthecase,pleasedosonow.

Youthenhaveonlytwocablestoplugin:aUSBcablebetweenyourcomputerandtheArduinoUnoboardandtheEthernetcable.SimplyconnecttheUSBcabletooneportofyourcomputer.

FortheEthernetcable,youhaveseveraloptions.Theeasiestthingyoucando,whichiswhatIrecommend,istoconnecttheEthernetcabledirectlyfromtheshieldtothemainrouterofyourhome.Usually,youwillhaveaWi-Firouterinyourhome,whichyouusetoenableWi-Ficonnectivityforyourcomputerandotherdevices.ThisroutershouldalsohavesomeEthernetports,whereyoucanconnectyourEthernetshield.TheadvantageofthissolutionisthatyourshieldwillautomaticallygetanIPaddressandwillhaveaccesstotheInternetautomatically.ThisassumesthatyourrouterisconfiguredforDHCP;gotoyourroutersettingstoenableDHCP.Asthisprocedurevariesdependingonthebrandofyourrouter,refertoyourrouterdocumentationtofindouthowtodothisonyourspecificrouter.

Ifyoudon’thavearouter,youcandirectlyconnecttheEthernetcabletoyourcomputer.Idon’trecommendthisalternative,asconfiguringyourcomputertoconnecttotheshieldandsharingtheInternetconnectionwiththeshieldisreallycomplex,anditalsodependsonyouroperatingsystem.

Ifyoureallydon’thaveaccesstoarouterbutyouhaveaccesstoaWi-Finetwork,IrecommendbuyingoneofthesesmallWi-FiroutersthathaveanEthernetport.ItcanconnecttoanyWi-FinetworkinrangeandsharetheconnectionautomaticallywithotherdevicesviaEthernet.

Forexample,asshowninthefollowingimage,IrecommendtheTP-LinkMR3020router:

Thisisanimageoftheassembledhardwareforthetasksinthischapter,withtheUSB

cableandtheEthernetcablepluggedintheproject:

Ifeverythingiswiredcorrectly,youshouldseetheONLEDontheEthernetshieldisswitchedon,aswellastheLINKLEDneartheEthernetport.

TestingyourconnectionNowthatthehardwareisready,wecanwriteourfirstsketchtotesttheEthernetshieldandtheconnectiontotheWeb.Notethatthepiecesofcodeshowninthissectionareonlythemostimportantpartsofthecode,andyoucanfindthecompletecodeinsidetheGitHubrepositoryofthebook.

StarttheArduinosketchbyincludingthefollowingrequiredlibrariestousetheshield:

#include<SPI.h>

#include<Ethernet.h>

TipDownloadingtheexamplecode

YoucandownloadtheexamplecodefilesforallPacktbooksyouhavepurchasedfromyouraccountathttp://www.packtpub.com.Ifyoupurchasedthisbookelsewhere,youcanvisithttp://www.packtpub.com/supportandregistertohavethefilese-maileddirectlytoyou.

Then,wehavetodefinetheMACaddressoftheEthernetshield.Thisaddressislocatedjustbehindtheshield,andyoushouldhavenoteditdownalready.Youhavetoenteritinthefollowingformat:

bytemac[]={0x90,0xA2,0xDA,0x0E,0xFE,0x40};

Wealsoneedtodefinewherewearegoingtoconnecttotesttheconnection.Youcanuseanywebpageyouwant,orevenperformasearchonGoogle,butforthisfirsttest,Iwanttouseasimplepage.

Ifoundthiswebsitewithasimpletestpagethatwe’lltrytograbwhilemakingarequestlaterinthesketch.Youcanalsosetupyourownpageifyouhaveawebserveronline,forexample,ifyouhaveabloghostedsomewhere.

Thewebsiteaddressisstoredinacharvariable:

charserver[]="www.brainjar.com";

Notethatyoucanalsouseotherpageshere,forexamplehttp://www.example.com/hello.

TheEthernetshieldwillthenautomaticallygettheIPaddressofthiswebsite.

TogetanIPaddressfortheEthernetshielditself,we’lluseDHCPtoautomaticallygetonefromtherouterweareconnectedto.However,ifDHCPfails,weneedtoassignadefaultaddresstotheshield.

ThisisstoredinanIPAddressvariable.Notethatyoucanputanythingyouwantinsidethisvariable.Asforthisfirstproject,wereallyneedDHCPtoworktogetconnectedtotheWeb.However,itisagoodpracticetospecifyanIPaddressinthesamesubnetasyourrouter,sotheshieldcanatleastconnecttoyourlocalnetwork.Forexample,theIPaddress



ofmycomputerwas192.168.1.100,soIspecifiedasimilarIPaddressfortheshield:

IPAddressip(192,168,1,50);

WecannowcreatetheinstancefortheEthernetclientwiththefollowingcode:

EthernetClientclient;

Now,inthesetup()functionofthesketch,wewilltrytogetanIPaddressusingDHCP.Ifyou’reconnectedtoarouter,thereisnoreasonitwouldfail.However,ifitdoesindeedfail,wewillautomaticallysetthedefaultIPaddressfortheshield:

if(Ethernet.begin(mac)==0){

Serial.println("FailedtoconfigureEthernetusingDHCP");

Ethernet.begin(mac,ip);

}

Then,wewillprintouttheIPaddressontheSerialportfordebuggingreasons:

Serial.begin(115200);

Serial.print("IPaddress:");

Serial.println(Ethernet.localIP());

Now,intheloop()functionofthesketch,wewillactuallyconnecttotheserver.Itstartsbycallingtheconnectfunctionandcheckswhetherweareindeedconnected.Ifthat’sthecase,weprintitoutontheSerialmonitorfordebuggingpurposes:

if(client.connect(server,80)){

if(client.connected()){

Serial.println("connected");

Nowthatweareconnected,wecansettheGETrequestforthetestpagewewanttoaccess:

client.println("GET/java/host/test.htmlHTTP/1.1");

client.println("Host:www.brainjar.com");

client.println("Connection:close");

client.println();

Aftertherequestissent,wewillreadthedatathatiscomingbackfromtheserver,tocheckwhethereverythingwentfine.WewillalsoprintoutthisdataontheSerialmonitor:

while(client.connected()){

while(client.available()){

charc=client.read();

Serial.print(c);

}

}

Finally,whenwearesurethattheclientisnotconnectedanymore,wewillprinttheinformationontheSerialmonitorandcalltheclose()functionontheEthernetclient:

if(!client.connected()){

Serial.println();

Serial.println("disconnecting.");

client.stop();

}

Finally,wedon’twanttocontinuouslydothisaction,butonlyrepeatiteveryfiveseconds.Thisisdonewithadelay()function:

delay(5000);

It’snowtimetotestthesketch.

NoteThecompletecodeforthisfirstchaptercanbefoundtheGitHubrepositoryofthebook:

https://github.com/openhomeautomation/arduino-networking/tree/master/chapter1

MakesurethattheEthernetcableispluggedinyourshieldandyourrouter,anduploadthesketchtotheArduinoboard.YoucannowalsoopentheSerialMonitor,andselectthecorrectSerialspeed(115200fortheArduinosketchofthischapter);that’sthefirstthingyoushouldsee,whichistheIPaddressofyourboard:

IPaddress:192.168.1.103

Then,theArduinoboardshouldconnecttotheserver:

Connecting…

Ifthisissuccessful,theoutputwillshowthatitisindeedconnected:

connected

Now,theArduinoboardwillsendtheGETrequesttotheserverinordertograbthecontentofthetestpage.TheserverwillanswerwithanHTTP200OKstatusiftherequestwassuccessful,alongwiththecontentsofthepage:

HTTP/1.1200OK

Content-Length:308

Content-Type:text/html

Last-Modified:Tue,27May200315:17:04GMT

Accept-Ranges:bytes

ETag:"6291ea76324c31:5897"

Server:Microsoft-IIS/6.0

X-Powered-By:ASP.NET

Date:Thu,15May201417:35:40GMT

Connection:close

Insidethislonganswer,youshouldseemanyHTMLtags,suchas<html>and<head>tags.Insidetheanswer,youshouldalsogetthecontentofthepageinsidea<p>tagasfollows:

<p>ThisisaverysimpleHTMLfile.</p>

Ifyoucanseethis,congratulations!YourEthernetshieldisworkingcorrectly!Finally,theArduinoboardwillalsodisplaythattheEthernetshieldhasbeendisconnectedfromtheremoteserver:

disconnecting


Ifeverythingworkedcorrectly,itmeansthatyourEthernetshieldisworkingcorrectly,anditcanconnectwithoutanyproblemstoyourlocalnetworkandtotheWeb.

Ifsomethingdidn’tworkasexpected,thereareseveralthingsyoucancheck.First,makesurethatallconnectionsarecorrectlymade,andthattheEthernetcableiscorrectlypluggedbetweentheshieldandyourrouter.

IftheDHCPfailsatthebeginningofthesketchandyourshieldcan’tgetanIPaddress,pleasecheckwhetherDHCPisactivatedwithoutlimitationsontheMACaddressesintheconfigurationpanelofyourrouter.

Finally,iftheArduinoboardcan’tconnecttotheremoteserver,firstcheckwhethertheserveritselfisworkingbyenteringtheURLofthetestpagemanuallyinyourbrowser.

SummaryInthisfirstchapterofthebook,webuiltourfirstprojectwiththeArduinoEthernetshield,onlytocheckwhethertheshieldwasworkingcorrectlyandwhetheritcouldconnecttoyourlocalnetworkandtotheInternet.WeonlymadesurethattheEthernetshieldcouldindeedbeconnectedtotheInternet,butthisalreadygaveyouanoverviewofeverythingthatyoucandowiththeEthernetshield.YousawhoweasyitistosendrequestswiththeEthernetshield,whichissomethingwewilluselaterinthebooktosenddatafromtheEthernetshieldtoaremoteserver.

Thesewerethemajortakeawaysfromthisfirstchapter:

First,wemadesurethatallthehardwarewascorrectlysetandthattheshieldwasconnectedtoyourrouterviaanEthernetcable.Then,webuiltthefirstsketchofthisbooksimplytotestthattheEthernetshieldcouldindeedconnecttothelocalnetworkandtheWeb.Totestthis,webuiltasketchthatconnectstotheWebandgrabsatestpagefromaremoteserver.Finally,weuploadedthiscodetotheboardandcheckedthateverythingwasworkingcorrectlybymonitoringthestatusoftheconnectionintheArduinoSerialMonitor.Wealsodefinedsomestrategiesonwhattodoifthesketchdidn’tworkandtheshieldcouldnotconnecttotheWeb.

Inthenextchapterofthebook,wearegoingtobuildourfirstapplicationusingtheEthernetshield.WearealsogoingtouseanEthernetclient,butthistimetoconnecttoaserverrunningonourowncomputerandtosendmeasurementsthatcomefromatemperatureandhumiditysensor.

Chapter2.SendingDatatoaWebServerInthepreviouschapter,wemadesurethatyourArduinoEthernetshieldcouldactuallyconnecttoyourlocalnetworkandtotheWeb.Inthischapter,wearegoingtobuildonthat,andbuildourfirstapplicationusingtheEthernetshield.

WearegoingtoseeinmoredetailhowtheEthernetclientworksbymeasuringdatafromadigitalsensorandsendingthisdatatoawebserver.Inthischapter,thiswebserverwillbeaserverrunningonyourowncomputer.

Thesewillbethemajortakeawaysfromthischapter:

First,wearegoingtochoosethetemperatureandhumiditysensorthatwewillalsouselaterinthebook.Wearealsogoingtoinstallthedifferentsoftwarecomponentsthatarerequiredforthischapter,especiallythelibrarytoplotdataonyourcomputer.Then,wearegoingtobuildtheArduinocodethatwillperformmeasurementsandsendthesemeasurementstothewebserverrunningonyourcomputer.Afterthat,we’llstartbuildingtheserver-sidecode.Inthefirstpart,wearegoingtobuildthecoderesponsibleforsimplyloggingthereceiveddataintoalocaldatabase.Finally,wewillinterfacethedatabasewithaliveplottinglibrarysothemeasurementscanbeseenastheycomefromtheEthernetshieldandareloggedinthedatabase.

HardwareandsoftwarerequirementsOnthehardwareside,youwillofcourseneedtheArduinoUnoboardandArduinoEthernetshield.

Youwillalsoneedasensortomeasuresomedata.AsthisbookisabouthowtousetheEthernetshieldandnothowtomeasuredatafromsensors,youcanactuallytakeanysensorofyourchoice.

IusedaDHT11sensor,whichisadigitaltemperatureandhumiditysensor.IchosethissensorforthischapterandformanychaptersofthebooksinceitisaverycheapsensorandeasytointerfacewithArduino.AlongwiththeDHT11sensor,youwillalsoneeda4.7kOhmresistor.

Youcanalsouseotherkindofsensors.Youcanuseanalogsensors,whichreturnasignaldependingonthemeasureddata.Forexample,theTMP36sensorisananalogtemperaturesensorthatreturnsavoltageproportionaltotheambienttemperature.

OtherkindofsensorsyoucanuseherearesensorsbasedontheSPIorI2Cprotocols,whicharedigitalcommunicationprotocolsthatareeasytousewithArduino.Forexample,youcanusetheBMP085orBMP180sensors,whichhaveanI2Cinterface,andyoucanalsomeasurethebarometricpressureandambienthumidity.

YouwillalsoneedabreadboardandsomejumperwirestomaketheconnectionsbetweenthesensorandtheEthernetshield.

Thisisalistofallthecomponentsthatwereusedforthischapter:

ArduinoUno(https://www.adafruit.com/products/50)ArduinoEthernetShield(https://www.adafruit.com/products/201)DHT11sensor(https://www.adafruit.com/products/386)Breadboard(https://www.adafruit.com/product/64)Jumperwires(https://www.adafruit.com/product/758)

Onthesoftwareside,thefirstthingyouwillneedisthelibrarytointerfacewiththesensoryouchosebefore.AsIchoseaDHT11sensorforthisproject,youwillneedtodownloadandinstalltheDHTlibrary:

https://github.com/adafruit/DHT-sensor-library

ToinstallanArduinolibrary,simplyunzipthecontentofthedownloadedfileintothe/librariesfolderofyourmainArduinofolder(orcreatethisfolderifitdoesn’texistalready).

Youwillalsoneedalibrarytoplotthedatastoredinthedatabase.Iusedtheflotlibrary,whichisveryconvenienttouseandallowsreal-timevisualizationofincomingdata.Thislibraryisincludedinthecodeofthischapter,butifyouwantmoreinformationonthelibraryyoucangotohttp://www.flotcharts.org/.

Aboutthedatabaseitself,thisprojectusesSQLite,whichisaliteandeasy-to-usedatabase.Itisperfectforsuchprojects,asitdoesn’trequireadatabaseserverrunningon

https://www.adafruit.com/products/50



https://www.adafruit.com/product/64



http://www.flotcharts.org/

yourcomputer.

ItcomespreinstalledonmanyoperatingsystemssuchasOSXorLinux,butifthat’snotthecase,goovertotheirwebsitetodownloadandinstallit:

http://www.sqlite.org/

IfyouareusingLinux,thebestoptionistoinstallSQLitewithyourLinuxdistributionpackagemanager.

NotethatitisalsopossibletouserelationaldatabasesotherthanSQLite,suchasMySQL.ManywebserverscomewiththeMySQLserveraswell,andyouwillonlyneedtomakesmallchangesinthecodeofthischaptertouseaMySQLdatabase.YoucanalsousenonrelationaldatabasessuchasMongoDB(http://www.mongodb.org/),butthiswillrequiremorechangesinthecode.

Finally,youwillalsoneedtohaveawebserverupandrunningtomakethisprojectwork.Youcanfindmoreinformationabouthowtosetupawebserverintheprefaceofthisbook.Ifyoudon’thaveawebserverinstalledyet,youcanvisitthefollowinglinkstogetone:

Windows:EasyPHP(http://www.easyphp.org/)orWAMP(http://www.wampserver.com/en/)OSX:MAMP(http://www.mamp.info/)Linux:LAMP(https://help.ubuntu.com/community/ApacheMySQLPHP)

http://www.sqlite.org/

http://www.mongodb.org/


http://www.wampserver.com/en/


https://help.ubuntu.com/community/ApacheMySQLPHP

HardwareconfigurationIt’snowtimetosetupthehardwareforthisproject.Atthispoint,ifyoufollowedthefirstchapter,youshouldalreadyhaveyourArduinoEthernetshieldpluggedintotheArduinoboard,andoneEthernetcableconnectingtheEthernetshieldandyourInternetrouter.Ifthat’snotthecasealready,pleasedoso.

TheonlythingyouwillhavetoconnectinthisprojectistheDHT11sensorandtheresistor.Youcanhaveanoverviewofthedifferentconnectionsyouhavetomakebylookingatthefollowingschematics:

First,plugtheDHT11sensortothebreadboard.Then,connectpinnumber1and2ofthesensorusingthe4.7kOhmresistor.

Now,forthepowersupply.Connectpinnumber1ofthesensortoArduino5V,andpinnumber4totheArduinoGND.Finally,connectpinnumber2oftheDHTsensortoArduinopinnumber7.

Thisiswhatitshouldlooklikeattheend:

Ifyourprojectlooksthesame,congratulations,youcanmovetothenextpartwherewearegoingtobuildtheArduinosketchforthisproject.

SendingdatatoaserverItisnowtimetobuildthesketchforourfirstapplicationusingtheArduinoEthernetshield.Butfirst,weneedonemorepieceofdata:thelocalIPaddressofyourcomputer.InsidetheArduinosketch,wearegoingtospecifywheretheArduinoEthernetshieldhastosendthedata.

FindingyourIPaddressiseasy,butitdependsonyouroperatingsystem.IfyouareusingOSX,youcanfindyourIPaddressinsideNetworkPreferences.

IfyouareusingWindows,youwillfindtheinformationyouneedundertheNetworkSettingsinyourControlPanel:

AnotherwayunderWindowsistogotoStart,thenRun,andtypecmd.Then,insidetheconsole,typeipconfigandhitEnter.Yourcomputer’sIPaddresswillbedisplayed.

IfyouareusingLinuxorOSX,youcansimplygotoaterminalandtype:

ifconfig

ThiscommandshouldprintyourIPaddressinsidetheterminalwindow.Itwillingeneralbesomethinglikeeth0oren0.ThisiswhatIhadonmymachine:

en0:flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST>mtu1500

etherb8:f6:b1:12:c4:d7

inet6fe80::baf6:b1ff:fe12:c4d7%en0prefixlen64scopeid0x4

inet192.168.1.100netmask0xffffff00broadcast192.168.1.255

nd6options=1<PERFORMNUD>

media:autoselect

status:active

SomeLinuxdistributionsmadethemovetoanothertoolcalledip.Touseit,simplygotoaterminalandtype:

ipaddr

Thiswillalsodisplayyourcomputer’sIPaddress.

WearenowreadytobuildtheArduinosketch.First,weneedtoincludetherequiredlibraries:

#include<SPI.h>


#include"DHT.h"

InserttheMACaddressofyourEthernetshield,whichyoucanfindonthebackoftheshield:


YouwillalsoneedtodefinethepinonwhichtheDHTsensorwasconnected,aswellasthetypeofsensoryouareusing:

#defineDHTPIN7

#defineDHTTYPEDHT11

NotethatyoudonotneedasensorconnectedtoyourArduinoboardtotestthisproject.Youcansimplysendthecontentofanyvariableasatest,orusetherandom()functionofArduinotogeneraterandomdatameasurements.

First,wewilldefineadefaultIPaddressfortheEthernetshield.Thesketchshouldnotusethisaddresssincewe’llattempttoconnectusingDHCP,butifDHCPfails,weneedthisdefaultIPaddress.IrecommendusinganaddressthatisinthesameIPdomainasyourcomputerIPaddress:


Then,wecandefinetheIPaddressoftheserver,whichinthiscaseisyourcomputer.ThisiswhereyouneedtoentertheIPaddressyougotbefore:

IPAddressserver(192,168,1,100);

WecanthencreateaninstanceoftheEthernetclient:


WecanalsocreateaninstanceoftheDHTlibrary:

DHTdht(DHTPIN,DHTTYPE);

Nowinthesetup()functionofthesketch,wefirsttrytouseDHCPtoautomaticallygetanIPaddressfortheEthernetshield.Thisisdoneusingthefollowingpieceofcode:

Serial.begin(115200);




}

Afterthisstep,weprinttheIPaddressontheSerialport:



Intheloop()functionofthesketch,thefirststepistotakemeasurementsfromtheDHT11sensor:

floath=dht.readHumidity();

floatt=dht.readTemperature();

Convertthesemeasurementsintostrings:

Stringtemp=String((int)t);

Stringhum=String((int)h);

Fordebuggingpurposes,wealsoprintthesevaluesontheSerialport.We’llchecklaterwhetherthesevaluesarecorrectwhentestingthesketch:

Serial.println("Temperature:"+temp);

Serial.println("Humidity:"+hum);

Now,weareactuallygoingtosendthedatatotheserver.Don’tworryaboutunderstandingwhattheserver-sidecodedoesfornow,aswe’lldealwiththatlater.First,wehavetoconnecttotheserverrunningonyourcomputer:




Ifthisissuccessful,wecanmaketherequest.AsinChapter1,DiscovertheArduinoEthernetShield,wearegoingtouseastandardGETrequest,andtopassthetemperatureandhumiditymeasurementsasarguments.Atthispoint,youwillalsoneedtoentertheIPaddressofyourcomputer.Thisisalldoneusingthefollowingpieceofcode:

client.println("GET/datalogger/datalogger.php?temp="+temp+"&hum="+

hum+"HTTP/1.1");

client.println("Host:192.168.1.100");


client.println();

Youcanseethatthecodecallsafilenamedatalogger.php,whichwearegoingtoexamineinthenextsection.

Then,aftertherequestismade,wecanreadtheanswerfromtheserver:




Serial.print(c);

}

}

Next,wecanclosetheconnectioniftheclientisnotconnectedtotheserveranymore:


Serial.println();


client.stop();

}

Wearealsogoingtorepeatthewholeloopeverysecond:

delay(1000);

NoteYoucanfindallthecodeforthissectionintheGitHubrepositoryofthischapter:


Now,ifwejustuploadedthecodetotheArduinoboard,notmuchwouldhavehappened,sincewedidn’tdoanythingontheserverside.TheArduinoboardwouldmaketherequest,butastherequestfiledoesn’texistontheserver,theserverwouldreturnanerrorcode.

Sofirst,weneedtobuildafileontheserverthatwillhandletherequestfromtheboardandlogthedatasomewhere.That’sexactlywhatwearegoingtodonext.


LogincomingdatainadatabaseInthissection,wearegoingtousePHPtobuildtheserver-sidepartoftheproject.IfyouareacompletenoviceinPHP,Irecommendthefollowingresourcetolearnthebasicsofthelanguage:

http://php.net/manual/en/tutorial.php

First,wearegoingtoseethecontentofthedatalogger.phpfile.ThisfilewillhandletherequestscomingfromtheArduinoboard,logthedatainadatabase,andanswerwithasimplemessage.Notethatthisfilehastobeinafoldernameddataloggeronyourwebserver.Wewillseetheimportantpartsofthecode.Togetthecompletecodeforthissection,pleaserefertotheGitHubrepositoryofthechapter.NotethatallthePHPcodeshouldbebetweenthe<php…?>tags.

ThefilestartsbyreceivingthedatafromtheGETrequestsentbytheArduinoEthernetshield:

$temperature=intval($_GET["temp"]);

$humidity=intval($_GET["hum"]);

WealsoinstantiatetheconnectionwiththeSQLitedatabase:

$db=newSQLite3('database.db');

Then,weneedtogivesomestructuretothedatabaseifthedatabasefileisbrandnew.IfyouarenotfamiliarwiththeSQLcommands,Iinviteyoutovisitthefollowinglink:

http://www.cs.utexas.edu/~mitra/csFall2013/cs329/lectures/sql.html

Wearegoingtocreatefourdifferentcolumnsinsidethedatabase:auniqueIDthatwillbeautomaticallyincrementedbySQLite,atimestamptoknowwhenthemeasurementwasmade,andthetemperatureandhumiditydata.Thisisdoneusingthefollowingpieceofcode:

$db->exec('CREATETABLEIFNOTEXISTSmeasurements(idINTEGERPRIMARYKEY,

timestampTIMESTAMPDEFAULTCURRENT_TIMESTAMPNOTNULL,temperature

INTEGER,humidityINTEGER);');

Notethatifyouareusingmoresensors(forexample,ifyouarealsomeasuringtheambientlightlevel),youcanaddmorefieldshere.Simplyaddanewfieldtothelist,forexample:pressureINTEGER.

Now,wecanactuallyinsertthedataasanewrowinthedatabase.SinceSQLiteautomaticallyaddstheIDandtimestampfields,wejustneedtoinsertthedataconcerningthetemperatureandhumidity:

$db->exec("INSERTINTOmeasurements(temperature,humidity)VALUES

('$temperature','$humidity');");

Ifyouneedtoinsertmoredataintothedatabase,forexample,ifyouhaveanothermeasurementtolog,youcansimplyextendthiscommandtoinsertmoredataintotheSQLitedatabase.

http://php.net/manual/en/tutorial.php

http://www.cs.utexas.edu/~mitra/csFall2013/cs329/lectures/sql.html

TipThissimplecodeillustrateshoweasyitistoinsertdataintotheSQLitedatabase.However,itleavesourserverexposedtoasecurityissueknownastheSQLinjection.Sinceourprojectismadeforyourownlocalnetworkonly,thisisnotreallyanissuehere.However,ifyouplantodeploytheprojectonline,Irecommendmodifyingthecodetosolvethissecurityproblem.Thefollowinglinkwillgiveyoumoreinformationaboutthisissuehttp://www.tutorialspoint.com/sqlite/sqlite_injection.htm.

Finally,wereplytotheArduinoboardwithasimplemessage:

echo"Datareceived";

Now,wehaven’tactuallytalkedaboutthedatabaseitselfyet.Thereisadatabase.dbfileincludedasanexampleinthecodeforthischapter,butIrecommendyousimplydeleteitandtrytomakeyourowndatabase.Youcansimplygotothedirectoryinaterminalwhereallfilesoftheprojectarelocatedandtype:

sqlite3database.db

TipIfyouareusingWindows,IrecommendusingConsoleasaterminal.Youcangetitatthefollowinglinkhttp://sourceforge.net/projects/console/.

Thiscommandwillcreateyourdatabasefile.Youcannowagainexitthedatabasefilebytypingthefollowingcommand:

.exit

NotethatifyouareunderLinux,youmighthavetochangethepermissionsonthedatabaseandthefolderthatcontainstheproject.Todoso,gotheproject’sfolderviaaterminalandtype:

chmod777database.db

Now,itistimetomakeafirsttestoftheproject.Makesurethatallthefilesoftheserverarelocatedinafoldercalleddataloggeronyourwebserver.YoucannowuploadtheArduinosketchtoyourboardandopentheSerialmonitor.YoushouldfirstseethatthesketchisconnectingtoyournetworkandreceivinganIPaddressasfollows:

IPaddress:192.168.1.103

Then,itshouldenterthefirstiterationoftheloop()function,andprintoutthetemperatureandhumiditymeasurements:

Temperature:21

Humidity:37

Afterthisstep,youshouldseethatthesketchisconnectedtoyourserver,andthattheserverisansweringwithastandard200OKanswer:

connected

HTTP/1.1200OK

http://www.tutorialspoint.com/sqlite/sqlite_injection.htm

http://sourceforge.net/projects/console/

Date:Mon,19May201408:09:57GMT

Server:Apache/2.2.23(Unix)mod_ssl/2.2.23OpenSSL/0.9.8yDAV/2PHP/5.4.10

X-Powered-By:PHP/5.4.10

Content-Length:13

Connection:close

Content-Type:text/html

Also,attheendofthisanswer,youshouldseetheconfirmationmessagethatwedefinedinthePHPfile:

Datareceived

disconnecting.

Ifyouareseeingthesemessages,congratulations!ItmeansthatyourArduinoEthernetshieldissuccessfullycommunicatingwiththewebserverrunningonyourcomputer,andisactuallyloggingsomedata.

Ifthisisnotthecase,firstcheckyourhardwareconnections.MakesuretheDHT11sensoriscorrectlywiredwiththeArduinoboard,andthattheEthernetcableispluggedintotheshieldandyourInternetrouter.Don’thesitatetoredoChapter1,DiscovertheArduinoEthernetShield,tomakesurethatyourEthernetshieldisworkingproperly.

Also,makesurethatthewebserverisactiveonyourcomputer,andthatallthefilesoftheproject(especiallythedatalogger.phpfile)arelocatedinafoldernameddataloggerinsideyourwebserverfolder.YoucantestthisindependentlyfromtheArduinoEthernetshield.Simplygotoyourfavoritewebbrowser,andtype:

localhost/folder_of_the_project/datalogger.php?temp=20&hum=40

Thiswilllogsomefakedatainsidethedatabase,soyoucanbesurethatthewebserverisrunningcorrectly.

Wearenowgoingtocheckontheserversidewhetherthedatawasrecordedcorrectly.Andweareactuallygoingtokilltwobirdswithonestone,sincethiscodewillalsobeusedinthenextsectiontoplotthedata.

Tocheckthatthedatawasrecordedcorrectly,youcansimplycreateafilenamedreadout.php,whichwillreaddatafromthedatabase,formatit,andprinttheformatteddatasoyouthatcanseeit.First,weneedtoaccesstheSQLitedatabase:

$db=newSQLite3('database.db');

Wethenneedtomakeaquerytothedatabasesoitreturnsthedatawewant.Inthisrequest,wearesimplygoingtotakeallthefieldsfromthetablecalledmeasurements.Thisisdoneusingthefollowingpieceofcode:

$results=$db->query('SELECTid,timestamp,temperature,humidityFROM

measurements');

Now,weneedtousePHPtoparsethisvariablethatcontainsalltheresultsfromthequery.Wesimplyuseawhilestatementforthat:

while($row=$results->fetchArray())

{

$dataset[]=array(strtotime($row['timestamp'])*

1000,$row['temperature']);

}

Notethatintheprocessofparsingtheresults,weformatthedatainanothervariable,sothatthescriptwewillusetoplotthedatacanuseit.Wealsoconvertthetimestampcolumnsothattheplottingscriptcanuseit.Inthisexample,wearejustgoingtodisplayandlaterplotthetemperature,whichiswhyweonlytakethesetwovariablesoutfromthedatabase.Youcan,ofcourse,dothesameforthehumidity.

Finally,weprintouttheformatteddataintheJSONformat:

echojson_encode($dataset);

Now,wecantestthisreadoutfile.Simplygoovertoaterminal,gotothefolderwherethefileislocated,andtype:

phpreadout.php

Thisshouldplotalltherecordingsthathavebeenmadesofar:

[[1400486855000,20],[1400486868000,20],[1400486879000,21],

[1400486890000,21],[1400486901000,21],[1400486912000,21],

[1400486922000,22],[1400486933000,23],[1400486944000,23]]

Whatareyouareseeingintheterminalwindowistherawdatathatwasrecordedforthetemperature.Itconsistsofseveralsmallarraysoftwoelements,whicharethetimestampandrecordedtemperature.IfyouwanttolearnmoreabouttheJSONformatthatthisPHPscriptisreturning,youcanvisithttp://json.org/.

Ifyoucanseethisrawdatabeingdisplayed,itmeansthatthedatacomingfromtheArduinoboardwascorrectlyloggedinyourcomputer.

http://json.org/

DisplayingtheresultsWearenowgoingtousethedatathatwasloggedinthedatabaseanddisplayitonagraphformoreconvenience.Forthistask,wearegoingtouseaJavaScriptlibrarycalledflot,whichisalreadyincludedinthecodeforthischapter.Thislibraryprovidesnicefunctionstoplotdataonawebpage,andalsoallowsyoutoplotdatainrealtime,soyouwillseethegraphbeingautomaticallyupdatedasmoredatacomesin.

EverythingwillhappeninsideanHTMLfilecalledplot.html.Wewillonlyseethemostimportantpartsofthecodehere.PleaserefertotheGitHubrepositoryofthechaptertogetthecompletefiles.Insidethisfile,youfirsthavetoincludethefilesrequiredfortheflotlibrary:

<scriptsrc="flot/jquery.js"></script>

<scriptsrc="flot/jquery.flot.js"></script>

<scriptsrc="flot/jquery.flot.time.js"></script>

YoualsoneedanelementintheHTMLpagethatwillhostthegraph.Thisisdoneusingthefollowingpieceofcode:

<divid="placeholder"style="width:800px;height:450px;"></div>

Let’salsodefinesomeoptionsfortheplot.SincethisisnowJavaScript,wehavetowritethiscodeinsidethe<script>…</script>tags.IfyouwanttolearnmoreaboutJavaScriptfirst,Irecommendthisexcellentinteractivetutorial:

http://www.codecademy.com/en/tracks/javascript

Becausewehavetimestampsasthex-axis,weneedtospecifythatthedataforthisaxisisaspecifictime,andthatwewanttodisplaythehours,minutes,andseconds:

varoptions={

xaxis:{

mode:"time",

timeformat:"%H:%M:%S"

}

};

Wealsoneedtoreceivethedataeverytimewecallthescripttoplotthedata.ThisisdonebyanAJAXcalltothePHPfilewecreatedbefore:

$.ajax({

url:"readout.php",

type:"GET",

dataType:"json",

success:onDataReceived

});

Notethatthiscodehastogoinsidetheupdate()functionintheJavaScriptcode.Youcandefinethisfunctionwith:

functionupdate(){

YoucanseethatthisAJAXcall,ifsuccessful,callsanotherJavaScriptfunction.This

http://www.codecademy.com/en/tracks/javascript

functionwillactuallytakethedataasanargumentandplotitwiththeoptionswedefinedbefore:

functiononDataReceived(series){

vardata=[];

data.push(series);

$.plot("#placeholder",data,options);

}

Allthiscodeiscontainedintheupdate()function,andthisfunctioniscalledcontinuously(every10milliseconds)sothattheplotisalwaysupdatedwhenanewdatapointcomesin:

setTimeout(update,10);

Finally,attheendofthescript,wecallthisfunctiononcetogetthegraphstarted:

update();

Itisnowtimetotestthepagewejustcreated.PlaceallthefilesinthedataloggerfolderonyourwebserverandmakesurethatthesketchisstillloadedontheArduinoboard.

Forillustrationpurposes,Iresetthemeasurementdatabaseatthispoint,butyoucanofcoursejustkeepthemeasurementsthatthesensoralreadyperformed.

Opentheplot.htmlfile.ThisistheresultIgotafterthefirsttwomeasurementpoints:

Toillustratethebehaviorofthesensorontheplot,Ipincheditwithmyfingersandreleaseditabitlater.Asexpected,thetemperaturewentupbeforegoingdownagainafterawhile.Thefollowingscreenshotistheresultonthewebpage:

Ifitdoesn’tworkatthispoint,therearemanythingsyoucancheck.First,makesureagainthatthecodefortheprevioussectionsisworkingandthattheArduinoEthernetshieldiscorrectlysendingdatatotheserver.Also,checkthatallthecodefilesarelocatedinsidethesamefolderonthewebserver.Andmakesurethatyouareaccessingplot.htmlviathelocalhostURLinyourbrowser.

Then,opentheJavaScriptconsoletocheckthateverythingisfine.Youwillusuallyfindtheconsoleinthedevelopertoolsofyourwebbrowser.Forexample,inChrome,youwillfindtheconsoleintheView|Developermenu:

Insidethisconsole,youwillbeabletoseewhetherthereareanyerrorsintheJavaScriptcodeonthepage,andthiswillusuallygiveyouagoodideaofwhatisgoingoninthepageandwhatyouhavetofix.

SummaryInthissecondchapterofthebook,webuiltourfirstapplicationbasedontheArduinoEthernetshieldandEthernetclientclass.WedidsomebasicmeasurementsontheArduinoboard,sentthesemeasurementsonalocalwebserver,andfinallydisplayedthisdatainrealtimeonagraph.

Toproceedfurtherwiththischapter,IinviteyoutocarefullyrepeatallthestepsofthischaptertoreallyunderstandwellhowtheArduinoEthernetshieldcommunicateswiththePHPcoderunningonyourcomputer.Youcanalsoaddmoresensorstotheprojectsandlogthisdatainsidethedatabase.Also,youcantrytoplotseveralvariablesatonceondifferentgraphs.

Thesewerethemajortakeawaysfromthischapter:

First,weinterfacedadigitaltemperatureandhumiditysensortotheArduinoboardsothatwecansendthemeasurementstoalocalwebserverusingtheEthernetshield.Wealsoinstalledsomeusefulsoftwarecomponentssuchasalibrarytoplotdatainawebpage.Then,webuiltanArduinosketchtosenddatadirectlytoawebserverrunningonyourcomputer.Afterthat,westartedbuildingtheserver-sidecodebycodingthefileresponsibleforloggingdataintoalocaldatabase.WealsotestedthiscodewiththeArduinoEthernetshield,andmadesurethatthedatawascorrectlytransmittedtotheserverandloggedinthedatabase.Finally,webuiltawebpagetoautomaticallyplotthedataasitisreceivedonthewebserver,usingaJavaScriptlibrarycalledflot.

Inthenextchapter,wearegoingtodosimilarthings,butusingacompletelydifferentapproach:insteadofrunningaclientontheArduinoboardandtransmittingthedataonalocalwebserver,wearegoingtoruntheserverrightontheArduinoboard.TheArduinoprojectwillconstantlydisplaythemeasurementsonawebpageandlogthedatalocallyonaSDcard.

Chapter3.DataLoggingStationInthischapter,wearegoingtocreatesomethingreallysimilartowhatwedidinChapter2,SendingDatatoaWebServer,thatismeasuringdatafromasensor,storingthedata,andsendingitbacktoawebserversothatitcanbeplotted.

However,thingsaregoingtobesimilaronlyontheappearancefront.InsteadofhavinganEthernetclientthatrunsontheArduinoboardandsendsdatatoaserver,wearegoingtomaketheArduinoboardmoreindependent.Inthefirstpartofthechapter,wearegoingtologthedatalocallyusingtheintegratedMicroSDcardreaderoftheEthernetshield.

Then,wearegoingtocreateaserverrightontheArduinoboard.Theboardwillmeasuredataasusual,buttheserverwillservethedatatotheincomingclients.Finally,wewilluseamodifiedversionofthecodeweusedintheChapter2,SendingDatatoaWebServer,toplotthemeasureddataonyourcomputer.

Thefollowingwillbethemajortakeawaysofthischapter:

First,wearegoingtobuildthehardwareforthisproject,includingthetemperatureandhumiditysensor,andtheSDcardtologthemeasureddata.Then,wewillcreatethefirstpartoftheproject,andlogdataautomaticallyontheSDcard,whichisinsertedinsidetheEthernetshield.Atthispoint,wearegoingtousetheInternetconnectionoftheEthernetshieldtoautomaticallyobtainthecurrenttimefromaNetworkTimeProtocol(NTP)timeserver.Finally,wearegoingtobuildawebserverandrunitontheArduinoboard.Youwillthenbeabletoaccessthedatameasuredbytheboardjustbyenteringintheaddressoftheboardinawebbrowser.WearealsogoingtomodifythecodefromthelastchaptertoobtainthemeasurementsfromtheArduinoboardandplotthemliveinyourbrowser.

HardwareandsoftwarerequirementsOnthehardwarefront,youwillofcourse,needtheArduinoEthernetshieldandanArduinoboardsuchastheArduinoUno.

Youwillalsoneedasensortomeasuresomedata.AsthisbookisabouthowtousetheEthernetshieldandnothowtomeasurefromsensors,youcouldactuallytakeanysensorofyourchoice.

IusedaDHT11sensor,whichisadigitaltemperatureandhumiditysensor.IchosethissensorforthischapterandformanychaptersofthebookasitisaverycheapsensorandeasytointerfacewithArduino.AlongwiththeDHT11sensor,youwillalsoneeda4.7kohmresistor.

Tologthedata,youwillneedtohaveaMicroSDcardthatyoucanplugintotheEthernetshield.Idon’thaveaspecificbrandtorecommend,butIusedaSanDiskMicroSDcardwithanormalSDadapter(whichworkedwellforme),soyoucanalsoplugitintoyourcomputertocheckwhetherthedatawascorrectlylogged.Also,makesurethattheSDcardisformattedusingtheFAT32format.

YouwillalsoneedabreadboardandsomejumperwirestocreatetheconnectionbetweenthesensorandtheEthernetshield.

Thefollowingisalistofallcomponentsthatwereusedforthischapter:

TheArduinoUno(https://www.adafruit.com/products/50)TheArduinoEthernetshield(https://www.adafruit.com/products/201)TheDHT11sensor(https://www.adafruit.com/products/386)AMicroSDcard(http://www.amazon.com/SanDisk-Micro-SDHC-Memory-Adapter/dp/B0052MHQM6)Abreadboard(https://www.adafruit.com/product/64)Jumperwires(https://www.adafruit.com/product/758)

Onthesoftwarefront,thefirstthingyouwillneedisthelibrarytointerfacewiththesensoryouchosebefore.IchoseaDHT11sensorforthisproject.YouwillneedtodownloadandinstalltheDHTlibraryfromhttps://github.com/adafruit/DHT-sensor-library.

ToinstallanArduinolibrary,simplyunzipthecontentofthedownloadedfiletoyourlibrariesfolderofyourmainArduinofolder(orcreatethisfolderifyouhaven’tdonesoalready).




http://www.amazon.com/SanDisk-Micro-SDHC-Memory-Adapter/dp/B0052MHQM6




HardwareconfigurationIt’snowtimetosetupthehardwareforthisproject.Atthispoint,ifyoufollowedanyofthepreviouschaptersofthisbook,youshouldalreadyhaveyourArduinoEthernetshieldpluggedintotheArduinoboard,andoneEthernetcableconnectingtheEthernetshieldandyourInternetrouter.Ifthat’snotthecasealready,pleasedoso.

TheonlythingyouwillhavetoconnectinthisprojectistheDHT11sensorandtheresistor.Youcanseeanoverviewofthedifferentconnectionsyouhavetomakebylookingatthefollowingschematicdiagram:

First,plugtheDHT11sensorintothebreadboard.Then,connectthepinnumber1and2ofthesensorusingthe4.7kohmresistor.

Nowcomesthepowersupply.Connectthepinnumber1ofthesensortotheArduino5V,andthepinnumber4totheArduinoGND.Finally,connectthepinnumber2oftheDHTsensortotheArduinopinnumber7.

Attheend,itshouldlooklikethefollowingimage:

Finally,simplyinserttheSDcardintotheSDcardslotontheEthernetshield.

LoggingdataonanSDcardLet’sstartwiththefirsttopicofthischapter—loggingdataonaSDcardusingtheintegratedSDcardslotoftheEthernetshield.WhatwearegoingtodoisperformsomemeasurementsontheArduinoboardandlogeachofthesemeasurementstotheSDcardinasimpletextfile.

However,comparedtotheprojectoftheChapter2,SendingDatatoaWebServer,wedon’tactuallyknowthedatewhenthemeasurementwastaken.Inthepreviouschapter,wesimplyusedthedateofthecomputer,butwedon’thavethisinformationhere.TogetthetimeontheArduinoboard,wearegoingtouseanotherstrategy.WearegoingtousetheEthernetshieldtoconnecttoanNTPtimeserver,grabthetimeoncewhentheArduinosketchstarts,andthenusetheTimelibrarytotrackthetimefromthere.

TolearnmoreabouttheTimelibrary,youcanvisitthefollowingpageontheArduinowebsite:

http://playground.arduino.cc/Code/Time

TheprocessofloggingdataonaSDcardstartsbyincludingthecorrectlibrariesasfollows:

#include"DHT.h"

#include<SD.h>

#include<Time.h>


#include<EthernetUdp.h>

#include<SPI.h>

Wealsoneedtodefinethesensortypeandthepintowhichthesensorisconnected.Thisisdonewiththefollowinglinesofcode:

#defineDHTPIN7

#defineDHTTYPEDHT11

TodefinetheMACaddressoftheEthernetshield,usethefollowinglineofcode:


TousetheSDcard,youwillalsoneedtodefinethechipSelectpin,whichisthepinnumber4ontheEthernetshield.Thisisdoneusingthefollowingline:

constintchipSelect=4;

Now,wearegoingtodealwiththeNTPserver.ThereareactuallyseveralNTPserversyoucanuse(youcanseetheIPaddressesofmanyoftheseserversinsidetheTimeNTPexamplethatcomewiththeTimelibrary).Youcanalsosetyourtimezonehere.TogetmoreinformationaboutwhichNTPserveryoucanuseandwhichtimezonetoset,youcanhavealookattheexampleTimeNTPsketch.ThissketchisgivenasanexampleinsidetheTimelibrary.Forthisproject,Iusedthefirstserveravailablewithtimezonenumber1,asshowninthefollowingcode:

http://playground.arduino.cc/Code/Time

IPAddresstimeServer(132,163,4,101);

constinttimeZone=1;

Toconnecttothisserver,wealsoneedtodefineanEthernetclient.Thistime,wearegoingtouseaprotocoldifferentfromtheearlierone,whichiscalledUDP.UDPisdifferentfromTCP—it’smuchsimplerandlighter.However,itdoesn’tguaranteethatthedatawascorrectlydelivered,whichTCPdoes.Youdon’tactuallyneedtocareaboutthedetailsofthisprotocol,astheTimelibraryhandleseverything.YoucanjustleavethedefaultUDPport,asshowninthefollowingcode:

EthernetUDPUdp;

unsignedintlocalPort=8888;

YoualsoneedtocreateaninstanceoftheDHTsensorasfollows:


Now,inthesetup()functionofthesketch,youneedtodefinethefollowingcoderesponsibleforgettinganIPaddressfortheEthernetshield:

Serial.begin(9600);


//nopointincarryingon,sodonothingforevermore:

while(1){


delay(10000);

}

}

Afterthat,wewilltrytoinitializetheSDcard,asshowninthefollowingcode:

Serial.print("InitializingSDcard…");

pinMode(10,OUTPUT);

Ifthisissuccessful,wewillprintoutamessageontheSerialport,asshowninthefollowingcode:

if(!SD.begin(chipSelect)){

Serial.println("Cardfailed,ornotpresent");

//don'tdoanythingmore:

return;

}

Serial.println("cardinitialized.");

WewillalsostarttheDHTsensorasfollows:

dht.begin();

Finally,stillinthesetup()function,wewillprintouttheIPaddressoftheEthernetshieldandcreatetheconnectiontotheNTPserver.NotethatherewearecallingafunctioncalledgetNtpTime,whichisdefinedlaterinthesketch.AsthisisafunctionprovidedbytheTimelibrary,wearenotgoingtolookintothedetailsofthisfunction.Thefollowingisthecodeforthispart:

Serial.print("IPnumberassignedbyDHCPis");


Udp.begin(localPort);

Serial.println("waitingforsync");

setSyncProvider(getNtpTime);

Now,intheloop()functionofthesketch,wewillfirstmeasurethetemperatureandhumidityfromthesensorusingthefollowingcode:



Secondly,wewillconvertthesemeasurementstostringsasfollows:



WearenowgoingtobuildastringthatcontainsthedateandtimeofthemeasurementusingtheTimelibrary.Thislibrarycontainsfunctionstogetthecurrenttime,day,ormonth,forexample,whicharecalculatedfromtheinitialcalltotheNTPserver.Forexample,callingtheday()functionwillreturnthecurrentday.Thefollowingpieceofcodereturnsastringwiththedateandtime:

Stringlog_time=String(day())+"/"+

String(month())+"/"+String(year())+""+

String(hour())+":"+String(minute())+":"+

String(second());

Wethenassemblethisstringwiththetemperatureandhumiditymeasurementsusingcommasasseparatorsbetweenthedifferentstrings,asshowninthefollowinglineofcode:

StringdataString=log_time+","+temp+","+hum;

WearenowgoingtowritethisdataontheSDcard.Wefirstneedtoopenthecardtowritedatausingthefollowingline:

FiledataFile=SD.open("datalog.txt",FILE_WRITE);

Ifthat’ssuccessful,wewillputthecontentsofthedataStringvariabletothisfilenameddatalog.txt,asshowninthefollowingcode:

if(dataFile){

dataFile.println(dataString);

dataFile.close();

Serial.println(dataString);

}

else{

Serial.println("erroropeningdatalog.txt");

}

Finally,wewillrepeattheoperationevery10seconds,butyoucan,ofcourse,modifythisdelaywiththefollowingline:

delay(10000);

Note

AllthecodeforthissectioncanbefoundinsidetheGitHubrepositoryofthischapterathttps://github.com/openhomeautomation/arduino-networking/tree/master/chapter3.

It’snowtimetotestthissketch.MakesurethattheEthernetcableispluggedintotheshieldandyourInternetrouter,andtheSDcardispluggedintotheEthernetshieldSDcardslot.YoucannowuploadthesketchtotheboardandopentheSerialMonitor.Thefollowinglineiswhatyoushouldseefirst:

InitializingSDcard…cardinitialized.

Then,youshouldseethatyourEthernetshieldhasanIPaddress,asshowninthefollowingline:

IPnumberassignedbyDHCPis192.168.1.103

YoushouldseethatthisshieldiscurrentlysynchronizingthetimewiththeNTPserver,asshowninthefollowingoutput:

waitingforsync

TransmitNTPRequest

ReceiveNTPResponse

Afterthat,youshouldseethatthefirstmeasurementismadeasfollows:

21/5/20149:32:13,22,38

Afterthedelayyoufixedinthesketch,youwillseethatasecondmeasurementismadewiththecorrespondingdateandtime.TobesurethatthesketchiscorrectlywritingdataontheSDcard,youcanletitrunforawhileandthendisconnecttheEthernetshieldfromthepowersupply.Afterthis,removetheSDcard,andreaditonyourcomputerviaanadapter.Youshouldseethefollowingscreenshot:


Asyoucansee,allthemeasurementswerecorrectlyloggedontheSDcard,andwecanclearlyseethattheintervalbetweentwomeasurementswas10seconds.

CreatingawebserveronArduinoFortherestofthischapter,wearegoingtotakeanotherapproach.WearestillgoingtomaketheArduinowiththeEthernetShieldworkasanindependentsystem,butthistimeweareevengoingtocreateawebserverontheArduinoboard.ThisisactuallysimilartotheprojectwesawintheChapter2,SendingDatatoaWebServer,butthistimeitistheArduinoboarditselfthatwilldisplaythedataasitismeasured.

Thesketchforthispartstartsbyincludingtherightlibraries,asshowninthefollowingcode:

#include"DHT.h"


#include<SPI.h>

Definethepinandthetypeofthesensorinthefollowingmanner:

#defineDHTPIN7

#defineDHTTYPEDHT11

Also,youhavetodefinetheMACaddressofyourEthernetshieldasusual,asshowninthefollowinglineofcode:


WewillalsodefineadefaultIPaddressincasetheDHCPfails,asshowninthefollowingline:


Thisiswherethenewfeaturecomesin.Sofar,weonlyusedtheEthernetClientclasstodefineaclientthatwillconnecttoaremoteserver.Here,however,becausewewanttocreateaserverrightontheArduinoboard,wearegoingtousetheEthernetServerclass,asshowninthefollowinglineofcode:

EthernetServerserver(80);

Youcanusetheport80foryourserver,asitwillbemucheasiertoaccesstheserverfromyourwebbrowser.

WealsoshouldnotforgettocreateaninstanceoftheDHTsensor.Thisisdoneusingthefollowingline:


Now,inthesetup()functionofthesketch,wewilltrytouseDHCPtogetanIPaddressfortheEthernetshieldusingthefollowingcode:




}

Stillinthesetup()function,wealsohavetostartourEthernetserver,andprintouttheIP

addressoftheserverusingthefollowingcode:

server.begin();

Serial.print("Serverisat");


Finally,wewillstarttheDHTsensorasfollows:

dht.begin();

Now,intheloop()partofthesketch,wewillperformthetemperatureandhumiditymeasurements,asshowninthefollowingcode:



Convertthemeasurementstostringsusingthefollowingcode:



Then,weneedtohandletheconnectionsthatcometotheArduinoboard,forexample,fromawebbrowser.Todoso,weareactuallygoingtocreateaninstanceoftheEthernetClientclasseverytimetheserverbecomesavailable.Asthisisaclasswealreadysawinpreviouschaptersofthebook,thisissomethingwealreadyknowhowtoworkwith.

Ifaconnectionisdetected,wecreatethisclient,andprintitoutontheSerialportfordebuggingpurposes,asshowninthefollowingcode:

EthernetClientclient=server.available();

if(client){

Serial.println("Newclient");

Thenextpartisabittechnical.Weneedtoreadouttherequestthatcomesfromtheclient,butalsodetectthemomentwhentherequestisoversothatwecanclosetheconnection.Thisishandledbyalwayscheckingwhetherthecurrentlineisblankornot.Thefirststepisthentoreadouttherequestthatcomesfromtheclient,characterpercharacter,usingthefollowingpieceofcode:

booleancurrentLineIsBlank=true;


//Readdata

if(client.available()){


Serial.write(c);

NotethattheincomingrequestisalsoprintedoutontheSerialportfordebuggingpurposes.Now,ifwedetectthatwehaveanendoflinecharacterandthatthecurrentlineisblank,it’sasignthattherequestisover,asshowninthefollowingline:

if(c=='\n'&&currentLineIsBlank){

Therefore,wecananswertheclient.WewillfirstsendastandardHTTPheaderthatstateseverythingwentOK,andthatwewanttorefreshthepageautomaticallyevery5seconds,asshowninthefollowingcode:

client.println("HTTP/1.1200OK");

client.println("Content-Type:text/html");


client.println("Refresh:5");//Refreshthepageautomaticallyevery5

sec

client.println();

client.println("<!DOCTYPEHTML>");

client.println("<html>");

Then,wewillprintoutthedatafromthemeasurementonthepageusingthefollowingcode:

client.print("Temperature:");

client.print(temp);

client.print("<br/>");

client.print("Humidity:");

client.print(hum);

client.println("<br/>");

client.println("</html>");

Therestofthefollowingcodeistheretodetectwhetherwereachedtheendoftherequestornot:

if(c=='\n'){

//Startinganewline

currentLineIsBlank=true;

}

elseif(c!='\r'){

//you'vegottenacharacteronthecurrentline

currentLineIsBlank=false;

}

Finally,wewillgivethebrowserasmalldelaytoreceivetheanswer,andwewillclosetheconnection,asshowninthefollowingcode:

//Givethewebbrowsertimetoreceivethedata

delay(1);

//Closetheconnection:

client.stop();

Serial.println("Clientdisconnected");

NoteAllthecodeforthissectioncanbefoundintheGitHubrepositoryofthischapterathttps://github.com/openhomeautomation/arduino-networking/tree/master/chapter3.

It’snowtimetotestthecodethatwewroteinthissection.Again,makesurethattheEthernetcableispluggedtotheEthernetshieldandtoyourrouter.Then,youcanuploadthecodetotheboard,andopentheSerialMonitor.YoushouldfirstseetheIPaddressofthewebserverrunningontheArduinoboardasfollows:


Serverisat192.168.1.103

Afterthat,thesketchwilljustdonothingwhilewaitingforanyincomingconnection.Tomakeaconnectionhappen,justgoovertoyourwebbrowserandtypeintheIPaddressoftheboard.YoushouldimmediatelyseetheGETrequestfromthebrowserbeingprintedoutintheArduinoSerialMonitor,asshowninthefollowingoutput:

Newclient

GET/HTTP/1.1

Host:192.168.1.103

Connection:keep-alive

Cache-Control:max-age=0

Accept:

text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8

User-Agent:Mozilla/5.0(Macintosh;IntelMacOSX10_9_3)

AppleWebKit/537.36(KHTML,likeGecko)Chrome/34.0.1847.137Safari/537.36

Referer:http://192.168.1.103/

Accept-Encoding:gzip,deflate,sdch

Accept-Language:fr-FR,fr;q=0.8,en-US;q=0.6,en;q=0.4,de;q=0.2

Aswecansee,thereisalotoftextandthisdependsonyourbrowser.However,theimportantthingisactuallythefirstlineoftherequest,whichmeansit’saGETrequesttoourArduinoboard.

Finally,aftertheArduinoanswerstheserver,theconnectionisclosedandthefollowingmessageisdisplayed:

Clientdisconnected

Inyourbrowser,youshouldalsodirectlyseethatthedataisbeingprintedoutonthepagecreatedbytheArduinoboard,asshowninthefollowingscreenshot:

Ifyoucanseethis,congratulations,youjustcreatedyourownwebserverthatrunsonanArduinoboard.Ifyoucan’tseeapage,firstmakesurethatArduinohasanIPaddressanditcanbeconnectedtoyourlocalnetwork.Todoso,repeattheinstructionsinChapter1,DiscovertheArduinoEthernetShield,again.

AlsomakesurethatyoucorrectlyenteredtheIPaddressoftheboardinyourbrowser.YoucanalsocheckontheSerialMonitorthatyouarenotreceivinganyerrormessagesfromtheDHTsensor,whichwillcompromisethebehaviorofthewebserver.

PlottingthedatalocallyToendthechapter,wearegoingtoseehowtoplotdatameasuredbytheArduinoboard.Todoso,wewillmodifytheArduinosketchalittlebit,andthenusepartofthecodefromthepreviouschaptertoplotthedatarightinyourwebbrowser.

First,wearegoingtomodifytheArduinosketchsothatitreturnsdatainamoreusefulformat;inthepresentcase,theJSONformat.Inplaceofthecoderesponsibletoprintoutthemeasurements,wearegoingtosimplyprintthedataintheJSONformat.Thisisdoneusingthefollowingpieceofcode:

client.println("HTTP/1.1200OK");

client.println("Content-Type:application/json");


client.println();

client.print("{\"temperature\":");

client.print(temp);

client.print(",\"humidity\":");

client.print(hum);

client.println("}");

Wecannowquicklytestthisproject.UploadthecodetotheArduinoboardagain,openyourwebbrowser,andgotothesameIPaddressyouusedbefore.Youshouldseethefollowinglineprintedonthepage:

{"temperature":24,"humidity":36}

Now,wealsohavetobuildtheserver-sidecodetoplotthedata.Thecodeisverysimilartothecodeofthepreviouschapter,soIwillonlydetailthedifferencesbetweenthetwoprojects.Inthepreviouschapter,itwastheboardthatwastryingtoreachouttheserverrunningonyourcomputer,andthedatalogger.phpfilewashandlingtherequests.Inthischapter,wearegoingtodothereverseandcalltheboardfromthewebserverrunningonyourcomputer.Todoso,wearegoingtouseamodulefromPHPcalledcURLtomakeGETrequeststoagivenURL;inthiscase,theURLoftheArduinoboard.

Thefirstthingwehavetodoismakechangestothedatalogger.phpfileandaddtheURLoftheArduinoboard,asshowninthefollowinglineofcode:

$url='http://192.168.1.103';

StartthecURLcall,asshowninthefollowinglineofcode:

$curl=curl_init();

WealsohavetosettheoptionsofthecURLcall.WewantthecalltoreturnthedatafromourArduinowebserver,andwealsowanttheURLtobetheonewedefinedbefore.Thisisdoneusingthefollowingcode:

curl_setopt_array($curl,array(

CURLOPT_RETURNTRANSFER=>1,

CURLOPT_URL=>$url,

));

Wecannowexecutethecommand,asshowninthefollowinglineofcode::

$resp=curl_exec($curl);

ClosethecURLcall,asfollows:

curl_close($curl);

Wegettheanswerinavariablethatcontainsthedatainastring.InordertoopenitwithPHP,weneedtoconvertittotheJSONformatfirst,andthenextractthetemperatureandhumidityfields.Thisisdoneusingthefollowingpieceofcode:

$json=json_decode($resp,true);

$temperature=intval($json["temperature"]);

$humidity=intval($json["humidity"]);

Therestofthefileisstrictlyidenticaltothecodewedevelopedinthepreviouschapter.

Now,wealsoneedtomakeasmallmodificationintheplot.htmlfile.Inthepreviouschapter,thedatawasautomaticallyloggedinsidethedatabaseastheArduinoboardwasconstantlysendingdatatotheserver.Here,weneedtomakethecallontheserverside.Thisisdonebyaddingthefollowingsmallpieceofcodejustbeforethecodethatreadsoutthedatafromthedatabase:

$.ajax({

url:"datalogger.php",

type:"GET",

});

Thismeansthatjustbeforethedataisreadfromthedatabasetobeplotted,wearecallingtheArduinoboardtogetthetemperatureandhumiditymeasurements.

NoteAllthecodeforthissectioncanbefoundinsidetheGitHubrepositoryofthischapterathttps://github.com/openhomeautomation/arduino-networking/tree/master/chapter3.

Wecannowtestthispartofthechapter.NotethatthecodefromtheGitHubrepositoryincludesanexampledatabasesoyoucantesttheprojectrightaway,butIrecommenddeletingthefilejustbeforetestingtheproject,soyouwillplotyourownmeasureddatawhiletestingthecode.

Youcanjustputallthecodefortheplottingpartinsideafolderattherootofyourwebserver.Then,opentheplot.htmlfileviathelocalhostURLinyourwebserver.Youshouldimmediatelyseethatdataisbeingplottedinsideyourwebbrowser.Afterawhile,youshouldgetagraphsimilartothefollowinggraph:


Ifyoucanseethisplotinyourbrowser,congratulations!ThismeansyoucanperformremotemeasurementsfromthewebserverrunningonyourArduinoboard.

Ifthisisnotthecase,thereareseveralthingsyoucancheck.ThisfirstthingyoucancheckismakingsurethattheArduinoboardcorrectlydisplaysthedatainaJSONformat.Todoso,youcansimplyentertheaddressofyourboardinabrowser.Then,checkwhetheryourwebserverisrunningonyourcomputerandthatyouhaveplacedallthefilesfromtheprojectinsidearepositoryinyourwebserver’smainfolder.Finally,makesurethatyouareaccessingtheHTMLfilefromthelocalhostURLinyourbrowserandnotbyclickingonitinsideyourfileexplorer.

SummaryLet’ssummarizewhatwedidinthischapter.WecreatedanindependentmeasurementstationwithArduinothatautomaticallymeasuresandservesthedatainsomeway.First,weloggedthedatalocallyonaSDcardandthenweservedthisdatausingawebserverrunningontheArduinoboard.

Thefollowingarethemajortakeawaysofthischapter:

1. First,webuilttherequiredhardwareforthischapter,andinsertedtheSDcardintotheEthernetshield.

2. Then,inthefirstpartoftheproject,weloggedthemeasureddataontheSDcardandusedaremotetimeservertoautomaticallygetthemeasurementtimes.

3. Finally,webuiltanewArduinosketchtohaveawebserverrunningontheArduinoboard.WethenmodifiedtheplottingcodefromthepreviouschaptersoitcancalltheserverontheArduinoboardtogetandplotthemeasureddata.

Thereare,ofcourse,manywaystoimprovethisproject.YoucanaddmoresensorstotheprojectandeitherlogthisadditionaldataonaSDcardorserveitonawebpageusingtheArduinowebserver.YoucanalsohavemanyoftheseboardsinyourhomeorevenoutsideandmakeyourcomputerpollalltheseArduinoserversataregularintervaltogettheirmeasurements.

Inthenextchapter,wearegoingtoworkagainwiththisideaofcreatinganindependentsystemwiththeArduinoEthernetshield.WearegoingtoconnectarelaytotheArduinoboard,soyoucanswitchalamponandoffremotely.Thisprojectwillcomeintwoflavors.First,wewillmakeasketchtocontroltherelayremotelyviayourwebbrowser.Inthesecondpartofthechapter,wewilluseaspeciallibrarysotherelaycanbecontrolledfromanywhereintheworld.

Chapter4.ControllingObjectsfromAnywhereInthischapter,wearegoingtodosomethingdifferenttowhatwedidintheotherchapters.WhatwedidsofarwasmeasuresomedataontheArduinoboardandtransmitthisdatabacktothenetworkusingtheEthernetshield.Inthischapter,wearegoingtocontroladeviceinsteadofmeasuringdata.

Todoso,wewillusearelayconnectedtotheArduinoboardwiththeEthernetshieldandcontrolthisrelayremotely.Wearealsogoingtoconnectasetofpowercablestothisrelaysoyoucandirectlyplugalampintoitsothatitcanbecontrolledremotely.

Inthefirstpartofthechapter,wearegoingtocontrolthisrelayremotelywithinyourlocalnetwork.Inthesecondpartofthechapter,wewilluseadedicatedwebservicetocontrolthisrelayfromanywhereintheworld.

Thefollowingwillbethemajortakeawaysfromthischapter:

First,wearegoingtoseehowtochoosethedifferentcomponentsforthisproject,includingtherelayandcablestoconnectadevicetotherelaysuchasalamp.Then,wewillassemblethedifferenthardwarecomponents,connecttherelaytotheArduinoboard,andthepowercablestotherelay.Afterthat,wewillwriteanArduinosketchtotestwhethertherelayisworkingcorrectlyandhasbeencorrectlyconnectedtothecircuit.Whenwearesurethattherelayisworking,wewillwriteanapplicationusingtheEthernetshieldalongwiththerelay.WearegoingtowriteasketchtocontroltherelayviaEthernetandthenbuildaninterfacetocontroltherelayfromyourwebserver.Finally,inthelastsectionofthechapter,wearegoingtouseadedicatedwebservicetocontroltherelayfromanywhereintheworld.Wearealsogoingtoadapttheinterfacewejustcreatedtocontroltherelayfromanywhere.

HardwareandsoftwarerequirementsLet’sfirstseewhatweneedforthisproject.Aswithalltheotherchapters,youwillneedanArduinoboardandtheArduinoEthernetshield.

Youwillalsoneedarelaymodule.Ireallyrecommendusingarelaythatisintegratedonaboard,withalltherequiredcomponentsontheboardaswell.Itwillavoidyouhavingtobuildyourownrelaymoduleonabreadboard,anditisalsomuchsafer.Indeed,thereisnoriskinwiringtherelayandothercomponentsinanincorrectfashion.Simplymakesurethattherelayyouchooseiscompatiblewith5Vinputvoltagelevels.Also,youhavetomakesurethattherelaymodulecanhandlethepowerofthedeviceyouaregoingtouseforthisproject.Forexample,thelampIusedwasa30Wlamp,andtherelaycouldhandlemorethan1000W,justtobeonthesafeside.Ichosea5VrelaymodulefromPolulu,asshown:

Youcansimplyusetherelayasitisandcontrolitwiththecodewearegoingtodevelopinthisproject,butthegoalofhavingarelayistoconnectadevicetoit.Forthisproject,Ichosetoconnectalamptotherelay,butbyfollowingtheinstructionsinthischapter,youwillbeabletoconnectanydevicethatusesastandardpowerplug.

Todoso,Iusedasetofpowercables,onewithamalesocketandonewithafemalesocket,asshowninthefollowingimage:

Themaleplugwillbeusedtoconnecttherelaytothemainpowerpluginthewallandthefemalesocketwillbeusedtoconnectthedevicetocontroltherelay.

NoteAlwaysbeverycarefulwhenconnectingwirestothemainelectricity.Makesurethatyoudon’ttouchanyoftheexposedpartsoftherelay,andmakesurethatthecablesthemselvesdon’thaveanyexposedcopper.Also,connecttheplugtotheelectricitylatestwhenassemblingtheproject.

Let’snowseethesoftwarerequirementsforthisproject.Asusual,youwillneedtohavetheArduinoIDEinstalled,alongwithawebserverrunningonyourcomputer.

Inthesecondpartofthechapter,wearegoingtouseaservicecalledTeleduinotocontroltheEthernetshieldfromanywhere.Tousethisservice,youwillneedtogetanAPIkey,whichyouwillhavetoinsertinsidetheArduinosketch.

Youcangetakeybyvisitingthefollowingaddress:

https://www.teleduino.org/tools/request-key

Youwillbetakentothefollowingpagewhereyoucangetyourkey:

https://www.teleduino.org/tools/request-key

YouwillalsoneedtoinstallafewArduinolibrariesforthischapter.

ThefirstoneyouwillneedistheaRESTlibraryforArduino,whichyoucanfindatthefollowinglink:

https://github.com/marcoschwartz/aREST

Finally,youwillalsoneedtodownloadandinstalltheTeleduinolibrary,whichyoucanfindhere:

https://www.teleduino.org/downloads/

Toinstallagivenlibrary,simplyextractthefoldertoyourArduino/librariesfolder(orcreatethisfolderifitdoesn’texistyet).


https://www.teleduino.org/downloads/

HardwareconfigurationNowlet’sseehowtoconnectthedifferentcomponentsoftheproject.Aswiththeotherchaptersofthebook,youwillneedtohavetheEthernetshieldpluggedintotheArduinoboard.YouwillalsoneedtoconnectanEthernetcablebetweentheEthernetshieldandyourrouter.

Then,youneedtoconnecttherelaymodule.Therelaymodulehasthreeinputpins:VCC,GND,andasignalpinusuallycalledSIG.YouneedtoconnecttheVCCpintoArduino5V,GNDtoArduinoGND,andfinallythesignalpintoArduinopinnumber7,whichisadigitalpin.Thefollowingimageshowsthesystematthispoint:

Then,youneedtoconnectthepowercablestotherelaymodule.Arelaymodulebasicallyhasthreeoutputpins:COM(forthecommonpin),NC(forthenormallyclosedpin),andNO(forthenormallyopenpin).

WhatwewantistohavetheCOMpinoftherelayconnectedtoonewireofthepowerplug,NCnotconnected,andNOconnectedtooneotherwireofthepowerplug.Thefollowingimagesummarizestheconnectionsatthisstage:

First,connectonepinofthefemalepowerplugtotheCOMpin.Then,connectonepinofthemalepowerplugtotheNOpin.Finally,connectthetworemainingcablestogether,forexample,usingatypicalelectricalscrewterminal.

Oncethisisdone,youcanconnectthedeviceyouwanttocontroltherelay.Connectthelampinsidethefemalepowersocket,andthenconnectthemalepowerplugtothepowerpluginthewall.Thefollowingimagerepresentsthesystematthispoint,withoutthedevicetocontrolbeingconnected:

Ifyouhavesomethingsimilar,congratulations!Youaredonewiththehardwareconnectionsforthischapter.

TestingtherelayWearenowgoingtobuildaverysimplesketchtotestthehardwareconnectionswejustmade.Thesketchwillsimplyswitchtherelayonandoffeverysecond.

Thesketchstartsbydeclaringtherightpinfortherelay:

constintrelay_pin=7;

Then,wesetthispinasanoutput:

pinMode(relay_pin,OUTPUT);

Then,intheloop()functionofthesketch,wesettherelaytoaHIGHstate:

digitalWrite(relay_pin,HIGH);

Wewaitfor5seconds:

delay(5000)

Then,weswitchtherelaypintoaLOWstateagain:

digitalWrite(relay_pin,LOW);

Wethenwaitagainfor5seconds:

delay(5000);

NoteThecodeforthissectioncanbefoundintheGitHubrepositoryforthischapterathttps://github.com/openhomeautomation/arduino-networking/tree/master/chapter4.

YoucannowuploadthecodetotheArduinoboard.Youshouldheartherelayswitchingonandoffeverysecond.Ifyouconnectalamptotheproject,forexample,youshouldalsoseeitswitchingonandoffeverysecond.


ControllingtherelayremotelyNow,wearegoingtobuildourfirstinterestingapplicationusingthesystemwejustassembled.WearegoingtobuildanArduinosketchtocontroltherelayfromanywherewithinyourlocalnetwork.Forexample,ifyourcomputerisconnectedviaWi-FitoyourrouterandtheEthernetshieldisconnectedtothesamerouter,youwillbeabletocontroltherelayviayourcomputer.TheadvantageofthisapproachinthissectionisthatevenifyourInternetconnectionisdown,youwillstillbeabletocontroltherelay.

Theapplicationstartsbyincludingthecorrectlibraries:

#include<SPI.h>


#include<aREST.h>

WesetuptheMACaddressoftheboard:


WealsodefineadefaultIPaddressfortheboardthatwillbeusedifDHCPfails:


WethencreateaninstanceoftheaRESTlibrary,whichwillhandletherequestthatcomestotheboard:

aRESTrest=aREST();

YoualsoneedtocreateaninstanceoftheEthernetserver:

EthernetServerserver(80);

Inthesetup()functionofthesketch,wegetanIPaddressusingDHCP,asshowninthefollowingcodesnippet:




}

PrinttheIPaddressontheSerialMonitor,usingthefollowingcode:

server.begin();

Serial.print("Serverisat");


Finally,intheloop()functionofthesketch,wecheckwhetherthereareincomingclientsandhandletheseclientswiththeaRESTinstance:

EthernetClientclient=server.available();

rest.handle(client);

NoteThecodeforthissectioncanbefoundintheGitHubrepositoryforthischapterat

https://github.com/openhomeautomation/arduino-networking/tree/master/chapter4.

YoucannowuploadthecodetotheArduinoboardandopentheSerialMonitor.YoushouldseetheIPaddressoftheboardbeingprintedout:

Serverisat192.168.1.103

Youcannowgotoyourwebbrowserandstarttypingincommands.TheaRESTlibraryallowsyoutodirectlycommandallthepinsoftheArduinoboardviaEthernet.Youcanfindthecompletedocumentationofthelibraryathttps://github.com/marcoschwartz/aREST.Forexample,wefirstneedtosetpinnumber7asanoutput.Thisisdoneusingthefollowingcommand:

http://192.168.1.103/mode/7/o

Youwillbegreetedwiththefollowingmessageinthebrowser:

PinD7settooutput

Now,tosetthepintoaHIGHstate,youcansimplytype:

http://192.168.1.103/digital/7/1

Youwillgettheconfirmationinyourbrowser:

PinD7setto1

Youshouldalsoheartherelayswitchingfromonestatetotheotherwhenyouenterthecommand.

Nowwearegoingtobuildtheserver-sideinterfacetocontroltherelayfromyourcomputerwithouthavingtoentercommandsmanuallyinyourbrowser.

TheinterfaceisbasedonHTML,JavaScript,andPHP.IntheHTMLfile,therearebasicallytwobuttons:onetoturntherelayonandonetoturntherelayoff.Thefollowingisthecodeforoneofthebuttons:

<buttonclass="btnbtn-blockbtn-lgbtn-primary"type="button"id="1"

onClick="buttonClick(this.id)">On</button>

Youcanseethatthebuttoncallsafunction,whichisdefinedinaJavaScriptfile.Nowlet’shavealookatthisfile.Thefirstthingwehavetodowhenthepageloadsissettherelaypintobeanoutput,justaswedidwhenwetypedcommandsdirectlyinthebrowser.Thisisdoneusingthefollowingpieceofcode:

window.onload=function(){

$.get("command.php",{command:"/mode/7/o"});

}

Youcanseethatwearecallingafilenamedcommand.php.Wewillseethedetailsofthisfilelater.Now,wesawearlierthateverytimeabuttonisclicked,itcallsafunctioncalledbuttonClick.ThefollowingfunctionisalsodefinedintheJavaScriptfile:

functionbuttonClick(clicked_id){

Dependingonwhichbuttonwasclicked,wesendthecorrespondingcommandtothe



Arduinoboard.Forexample,fortheOnbutton,weputaHIGHstateontherelaypin,asshowninthefollowingcode:

if(clicked_id=="1"){

$.get("command.php",{command:"/digital/7/1"});

}

Finally,wehavetolookatthePHPfilethatwillactuallysendthecommandtotheboard.WefirstneedtogetthecommandthatwassentbytheJavaScriptfileandstoreitinavariable:

$command=$_GET['command'];

Then,weneedtosettheURLtowhichwewillsendthecommand.Tosendthecommandtotheboard,wewilluseaPHPmodulecalledcURL,whichwilldoexactlythesameaswhatwejustdidfromthewebbrowser.

Atthispoint,youwillhavetomodifytheIPaddressdefinedinthePHPfileandreplaceitwiththeIPaddressofyourboard.Thefollowingpieceofcodedoesjustthat:

$service_url='http://192.168.1.103'.$command;

$curl=curl_init($service_url);

Then,wecanactuallyperformthecURLcallusingthefollowingpieceofcode:

curl_setopt($curl,CURLOPT_IPRESOLVE,CURL_IPRESOLVE_V4);

curl_setopt($curl,CURLOPT_CONNECTTIMEOUT,0.5);

$curl_response=curl_exec($curl);

curl_close($curl);


Wecannowtesttheinterface.Makesurethatallthefilesofthisinterfacearestoredinsideafolderattherootofyourwebserverfolder,andalsomakesurethatthewebserverisrunning.Then,gotothisfolderviathelocalhostpathinyourbrowserandopentheHTMLfile.Youshouldseethefollowingscreenshot:

Trytoclickononeofthebuttons:youshouldhearthattherelayinstantlyswitches


accordingtothebuttonyouclicked.

NoteWhenyouloadedtheinterfaceinyourbrowser,therelaypinwasalsoautomaticallysettobeanoutput.

ControllingtherelayfromanywhereInthelastsectionofthischapter,wearegoingtotakeanotherapproach.Sofar,wehaveaserverrunningonourArduinoboard,whichcanreceivecommandsfromanydeviceonyourlocalnetwork.However,thisisnotconvenientifyouwanttocontroladevicefromanywhereintheworld.Forexample,youwanttoactivatealampinyourhomeatgivenintervalswhenyouareawayfromyourhome.

Todoso,wearegoingtousetheTeleduinoservice,whichallowsyoutodoexactlythat.TheArduinoEthernetshieldwillbeconstantlyconnectedtothisservice,soyoucantransmitcommandstotheboardfromanywhereintheworldifyouhaveanInternetconnection.WearegoingtobuildanewsketchfortheArduinoboardandthenadapttheinterfaceaccordingly,soyoucancontroltherelayfromanywhereintheworldrightfromyourwebbrowser.

Youfirstneedtoincludetherequiredlibraries:

#include<EEPROM.h>

#include<Servo.h>

#include<Wire.h>

#include<Teleduino328.h>

#include<SPI.h>


ThenyouneedtodefinetheMACaddressofyourEthernetshield:


Then,definealotofparametersfortheTeleduinoservice.AswewilluseDHCPtogetanIPaddress,youdon’tneedtochangeanythinginthefollowingcode:

IPAddressdeviceIp(192,168,1,100);//OnlyifuseDhcpisfalse

IPAddressgatewayIp(192,168,1,1);//OnlyifuseDhcpisfalse

IPAddressdnsIp(192,168,1,1);//OnlyifuseDhcpisfalse

IPAddresssubnet(255,255,255,0);//OnlyifuseDhcpisfalse

IPAddressserverIp(173,230,152,173);//OnlyifuseDnsisfalse

charserverName[]="us01.proxy.teleduino.org";//OnlyifuseDnsistrue

unsignedintserverPort=5353;//Canbesettoeither53or5353

bytestatusLedPin=8;

Wealsoneedtoenterthekeythatyougotatthebeginningofthechapter.However,youwillneedtoconvertthiskeytothecorrectformatsothatyoucaninsertitinsidetheArduinosketch.

YoucandosobyvisitingthefollowingURL:

https://www.teleduino.org/tools/arduino-sketch-key

Youwillbepromptedtoinsertthekeyinsidethenewwindow,asshowninthefollowingscreenshot:

https://www.teleduino.org/tools/arduino-sketch-key

YoucanthencopyandpastetheresultinsidetheArduinosketch:

bytekey[]={0x64,0x26,0xFF,0xC9,

0x20,0x4D,0xF1,0xCF,

0xAE,0x42,0xD4,0x1A,

0xED,0x6C,0xB0,0xB7};

YoualsoneedtodefinethefollowingvariablessothattheTeleduinoservicecanwork:

bytedata[257];

bytedataLength;

bytehexStage;

unsignedlonglastInstruction=0;

unsignedlonglastRefresh=0;

bytestage=0;

Finally,defineanEthernetclient:

EthernetClientClient;

TherestofthesketchcomesfromtheTeleduinoexampleandwon’tbedetailedhere.


It’snowtimetomakeafirsttestofthissketch.UploadthesketchtoyourArduinoboard,andthengotoyourwebbrowser.Youcannowdirectlysendcommandstoyourboard.First,wearegoingtosettherelaypinasanoutputasseenearlier.Thisisdoneusingthefollowingcommand(whereyouhavetoinsertyourownkeyatthekparameter):

http://us01.proxy.teleduino.org/api/1.0/328.php?k=yourKey

&r=definePinMode&pin=7&mode=1

Youwillbegreetedbyaconfirmationmessageinsideyourwebbrowser.YoucannowswitchtherelaypintoaHIGHstateusingthefollowingcommand:

http://us01.proxy.teleduino.org/api/1.0/328.php?

k=yourKey&r=setDigitalOutput&pin=7&output=1


Bydoingso,youshouldheartheclickoftherelay,meaningthecommandwascorrectlysent.Youwillalsobegreetedbyaconfirmationmessageinsideyourbrowser.

Now,wearegoingtomodifytheinterfacesoyoucancommandtherelayfromanywhereusingyourwebbrowser.InsidetheJavaScriptfile,youwillthenneedtodefineyourTeleduinoAPIkey:

varkey="yourAPIkey";

Then,wehavetochangethecommandparameterstofittheTeleduinoAPIandmentionthekeyaswell,asshowninthefollowingcode:

window.onload=function(){

$.get("command.php",{

key:key,command:"definePinMode&pin=7&mode=1"});

}

Also,wehavetochangethecommandparametersandmentionthekeyforthefunctionthatiscalledwhenabuttonisclicked:

if(clicked_id=="1"){

$.get("command.php",{

key:key,command:"setDigitalOutput&pin=7&output=1"});

}

InsidethePHPfile,wenowhavetogettwoparameters,thecommandandAPIkeyfromTeleduino:

$key=$_GET['key'];

$command=$_GET['command'];

WealsoneedtomodifytheserviceURL,asshowninthefollowingcode:

$service_url='http://us01.proxy.teleduino.org/api/1.0/328.php?k='.

$key.'&r='.$command;

$curl=curl_init($service_url);

Therestofthefilesarestrictlyidentical,asseenintheprevioussection.


Youcannowputallthefilesforthismodifiedinterfaceinsideafolderattherootofyourwebserver.Also,makesurethatthewebserverisstillrunning.YoucanopentheHTMLfileandyoushouldseeexactlythesameinterfaceasbefore.

Youcannowtrytoclickonabuttonandyoushouldinstantlyheartherelayswitch.Theadvantageovertheprevioussectionofthechapteristhatthisinterfacecannowworkfromanywhere.YoucanbeinonepartoftheworldandhaveyourEthernetshieldinanotherpartoftheworldanditwouldstillwork.


SummaryInthischapter,weinterfacedarelaytotheArduinoboardandtheEthernetshieldsothatitcanbecontrolledremotely.Todoso,weusedtwodifferentapproaches,eachwiththeirownadvantagesanddisadvantages.First,wekeptthingslocalandcontrolledtherelayfromwithinyourlocalnetwork.ThissolutionhastheadvantagethatevenifyourInternetconnectionisdown,theprojectstillworks.

Then,weusedadedicatedwebservicetocontroltherelayfromanywhere.Thisisclearlyanadvantageofthelatterapproach;however,itwillnotworkifyourEthernetshieldisnotconnectedtotheweb.

Thefollowingwerethemajortakeawaysfromthischapter:

First,wechosethedifferentcomponentsfortheproject,andassembledthemsothatwecancontroladevicefromtheArduinoboardsuchasadesklamp.Then,wewrotethefirstsketchtotesttheprojectbysimplyswitchingtherelayonandoff.Afterthat,webuiltthefirstapplicationbasedonthehardwarewejustassembled.WeusedadedicatedlibrarysothattheArduinoboardcouldreceivecommandsfromthenetworkusingtheEthernetshield.Wealsobuiltasimpleweb-basedinterfacesothatyoucancontroltherelayfromagraphicalinterfacerunningonyourcomputer.Finally,weusedawebservicecalledTeleduinotocontroltherelayfromanywhereintheworld.Wealsomodifiedthegraphicalinterfacesothatwecancontroltherelayfromanywhere.

Inthenextchapter,wearegoingtotakeyetanotherapproachandusetheEthernetshieldtoconnectourArduinoprojectstotheInternetofThings.WearegoingtoperformsomemeasurementsontheArduinoboardandsendthisdatarighttoacloudservice.Usingthisservice,wewillbeabletomonitorthemeasurementsthatcomefromtheboardinrealtimeandfromanywhereintheworld.

Chapter5.InternetofThingswithXivelyInthepreviouschaptersofthebook,wemainlykeptthingslocalwhenperformingmeasurementsontheArduinoboardwiththeEthernetshield.Forexample,wesentsomemeasureddatabacktoadatabaseonyourcomputeranddisplayedthemeasurementsthere.

Inthischapter,wearegoingtotakeadifferentapproach.WearegoingtointegratetheEthernetshieldintoanInternetofThingsperspective.Thismeansthatinsteadofloggingmeasurementslocallywithinyourlocalnetwork,wearegoingtoautomaticallysendthemeasureddatatoacloudservicecalledXively.ThepurposeoftheXivelywebsiteistostoredatathatcomesfromyourdevicesanddisplaythisdataontheirwebsite.Thisway,yourdatawillbeavailableatanytimeandcanbeaccessedfromanywhere.

Thefollowingwillbethemajortakeawaysfromthischapter:

First,wearegoingtobuildthehardwareforthisprojectaroundtheEthernetshieldandtheDHT11temperatureandhumiditysensor.Then,wewillcreateanaccountontheXivelywebsite.WewillalsoconfigurethisaccountsothatwecansendthemeasureddatatoitusingtheArduinoEthernetshield.Whentheaccountiscorrectlyset,wewillusetheaccountinformationsuchastheXivelyAPIkeytobuildtheArduinosketchforthisproject.Finally,wewilluploadthesketchtotheArduinoboardandtestit.WewillcheckthatthedataiscorrectlysenttotheArduinoboardandvisualizetherecordeddatainrealtimeinyourbrowser.

HardwareandsoftwarerequirementsOnthehardwareside,youwillofcourseneedtheArduinoEthernetshieldandanArduinoboardsuchastheArduinoUno.

Youwillalsoneedasensortomeasuresomedata.AsthisbookisabouthowtousetheEthernetshieldandnothowtomeasurefromsensors,youcanactuallyuseasensorofyourchoice.

IpickedaDHT11sensor,whichisadigitaltemperatureandhumiditysensor.IchosethissensorasitisaverycheapsensorandeasytointerfacewithArduino.AlongwiththeDHT11sensor,youwillalsoneeda4.7kohmresistor.

YouwillalsoneedabreadboardandsomejumperwirestomaketheconnectionsbetweenthesensorandtheEthernetshield.

Onthesoftwareside,thefirstthingyouwillneedisthelibrarytointerfacewiththesensoryouchosebefore.AsIchoseaDHT11sensorforthisproject,youwillneedtodownloadandinstalltheDHTlibraryfromhttps://github.com/adafruit/DHT-sensor-library.

ToinstallanArduinolibrary,simplyunzipthecontentsofthedownloadedfileintoyourlibrariesfolderofyourmainArduinofolder(orcreatethisfolderifitdoesn’texistalready).


HardwareconfigurationIt’snowtimetosetupthehardwareforthisproject.Atthispoint,ifyoufollowedoneofthepreviouschapters,youshouldalreadyhaveyourArduinoEthernetshieldpluggedintotheArduinoboard,oneEthernetcableconnectingtheEthernetshield,andyourInternetrouter.Ifthat’snotthecasealready,pleasedoso.

TheonlythingyouwillhavetoconnectinthisprojectistheDHT11sensorandtheresistor.Youcanhaveanoverviewofthedifferentconnectionsyouhavetomakebylookingatthefollowingschematicdiagram:

First,plugtheDHT11sensortothebreadboard.Then,connectpinnumbers1and2ofthesensorusingthe4.7kohmresistor.

Nowcomesthepowersupply.Connectthepinnumber1ofthesensortotheArduino5Vandthepinnumber4totheArduinoGND.Finally,connectthepinnumber2oftheDHTsensortotheArduinopinnumber7.

Attheend,itshouldlooklikethefollowingimage:

Youarenowdonewiththehardwareconfigurationofthisprojectandcanmovetothenextstep,whichiscreatinganaccountonXively.

CreatingyourXivelyaccountThefirstthingwehavetodotousetheXivelyserviceiscreateandconfigureaXivelyaccount.YouneedtocreateanaccountonXivelysothatwecansenddatatotheirservice.XivelyisbasicallyanonlineplatformforconnectedobjectssuchasourEthernetshield.Theservicewillautomaticallystorethedatathatwesend.Itwillalsodisplaythemeasureddataintheformofgraphsthatareupdatedinrealtimeasthedatacomesin.

TheveryfirststepistogoovertotheXivelysignuppageontheirwebsiteathttps://xively.com/signup/.Youwillarriveatapagewhereyoucanenteryourpersonaldetails:

Then,youwillneedtocreateadevice,whichisavirtualentityontheXivelywebsite.Thisdevicewillreceivethemeasureddata.Whenyoucreateanewdevice,youwillneedtoenteranameforyourdevice:

https://xively.com/signup/

Then,youcanaddchannelstoyourdevice.AchannelonXivelyislikeavariableorarowinadatabase;itistheentitythatwillreceiveaspecificmeasurementfromtheArduinoboard.Youcancreateanewchannelonthepageofyourdevicebyclickingonthebuttonshowninthefollowingscreenshot:

Youwillneedtoentersomenameforyourchannels.Youwillhavetocreatetwoofthemforthisproject:onecalledTemperatureandonecalledHumidity.

Then,youwillneedtogetsomeinformationaboutyouraccount,whicharealllocatedonthedevicepage.

ThefirstoneisthefeedID,whichidentifiesthisspecificdevice.Youcanfinditinthefollowingsectionofthepage:

Then,youwillhavetogetyourAPIkey,whichisspecifictoyouraccount.Youcanalsofinditonthedevicepage,asshowninthefollowingscreenshot:

YouwillneedtoenterthesetwokeysinsidetheArduinosketchthatwewillbuildinthischapter,sokeepthemathand.

SendingdatatoXivelyWearenowgoingtobuildtheArduinosketchforthisproject.ThegoalistomeasuredataontheArduinoboard,connectwiththeXivelyserver,andsendthedata.

Thefirststepistoincludethefollowingrequiredlibraries:

#include<SPI.h>


#include"DHT.h"

EntertheMACaddressofyourboard:


WecanthendefinethepinandthetypeoftheDHTsensorasfollows:

#defineDHTPIN7

#defineDHTTYPEDHT11

Createaninstanceonthesensor,asshowninthefollowingline:


CreateaninstanceoftheEthernetclient:


WealsodefineadefaultIPaddressfortheboard:


Inthesketch,wealsosettheaddressofthesecuredXivelyserverthatwewillconnecttousingtheEthernetshield:

IPAddressserver(216,52,233,120);

Now,wehavetomodifythesketchalittlebittoenteryourowninformationaboutyourXivelyaccount.ThisiswhereyouhavetoenteryourAPIkeyandfeedIDthatyougotintheprevioussection.Usingthefollowingcode,youcandefineyourAPIkeyandfeedID:

#defineWEBSITE"api.xively.com"

#defineAPI_key"yourAPIKey"

#definefeedID"yourFeedID"

Inthesetup()functionofthesketch,wecannowuseDHCPtogetanIPaddressforthesketch,asshowninthefollowingcode:

//StarttheEthernetconnection




}

Fordebugpurposes,weprintthisIPaddressontheSerialMonitor:



Now,intheloop()functionofthesketch,wewillmakethemeasurementswiththeDHTsensor,formatthedataforXively,andsendthisdatatotheXivelyserver.

Thefirststepistomakethemeasurements.Thisisdonewiththefollowinglinesofcode:

floathumidity=dht.readHumidity();

floattemperature=dht.readTemperature();

WethenneedtoformatthismeasureddatasotheXivelyservercanunderstandit.Indeed,Xivelydefinesaspecificformattoreceivedata.Alltheformatsaredefinedathttps://xively.com/dev/docs/api/communicating/data_formats/.

Inourcase,wewillneedtoputthedatainaJSONstringaccordingtotheXivelyspecifications.Thisisdoneusingthefollowingpieceofcode:

intlength=0;

Stringdata="";

data=data+"\n"+"{\"version\":\"1.0.0\",\"datastreams\":[{\"id\":

\"Temperature\",\"current_value\":\""+String((int)temperature)+"\"},"

+"{\"id\":\"Humidity\",\"current_value\":\""+String((int)humidity)+

"\"}]}";

Serial.println(data);

length=data.length();

YouwillnotethatwealsogetthelengthofthestringthatwewillalsoneedinordertosendthedatatotheXivelyserver.Also,weareusingbackslashesbeforequotationsmarkstoindicatethatwewanttotransmitquotationmarksandnottheendofthestring.

Then,wewillactuallyconnecttotheXivelyserverandsendthedata.ThisisdonebyusingaPUTrequestandsendingaJSONfiletotheXivelyserver.Intheheaderoftherequest,wedefinethefeedIDoftheXivelydeviceandwealsotransmityourXivelyAPIkey.

Wealsoneedtosendthedatawedefinedbeforeinthebodyoftherequest.Thisisdoneusingthefollowingpieceofcode:




client.println("PUT/v2/feeds/"+String(feedID)+".jsonHTTP/1.1");

client.println("Host:api.xively.com");

client.println("X-ApiKey:"+String(API_key));

client.println("Content-Length:"+String(length));

client.print("Connection:close");

client.println();

client.print(data);

client.println();

}else{

Serial.println(F("Connectionfailed"));

return;

}

Then,afterthedataissent,wereadbackthedatacomingfromtheserverandprintthe

https://xively.com/dev/docs/api/communicating/data_formats/

answerontheSerialMonitorfordebuggingpurposes,usingthefollowingpieceofcode:




Serial.print(c);

}

}

Finally,whenitisover,westoptheconnection.Thisisdonewiththefollowingcode:


Serial.println();


client.stop();

}

Werepeattheentireprocessevery10secondswiththefollowingline:

delay(10000);

NoteAllthecodeforthischaptercanbefoundontheGitHubrepositoryofthischapterathttps://github.com/openhomeautomation/arduino-networking/tree/master/chapter5.

ItisnowtimetotestthesketchanduploaddatatoXively.YoucanuploadthesketchtoXivelyatthispoint,andopentheSerialMonitorintheArduinoIDE.YoushouldseethattheIPaddressoftheboardisbeingprintedout,andthatthesketchisconnectedtotheXivelyserver:

IPaddress:192.168.1.104

Connecting…

YoushouldalsoseehowthedatawasformattedforXively:

{"version":"1.0.0","datastreams":[{"id":"Temperature","current_value"

:"24"},{"id":"Humidity","current_value":"37"}]}

Afteramoment,youshouldseetheanswercomingbackfromXively.IfthedatawassentcorrectlytotheXivelyserver,youshouldseea200OKcodebeingprintedouttotheSerialMonitor:

HTTP/1.1200OK

Date:Wed,21May201415:02:49GMT

Content-Type:application/json;charset=utf-8

Content-Length:0

Connection:close

X-Request-Id:e44becaa5231354568262013fa713d9f099ffc83

Cache-Control:max-age=0

Vary:Accept-Encoding

ThismeansthatthedatawascorrectlyreceivedbytheXivelyserver,andinanunderstandableformat.

Ifthatisnotthecase,thereareseveralthingsyoucancheck.First,makesurethatthe


InternetconnectionofyourEthernetshieldisworking,andthattheshieldisindeedreceivinganIPaddress.Then,makesurethatyoucorrectlyenteredyourXivelyinformation,meaningtheAPIkeyandthefeedID.Also,checkthatyoucorrectlyformattedyourdataintheJSONformat,whichweintroducedwhilewritingthesketch.Finally,makesurethattheDHTsensoriscorrectlywiredandmeasuringdataproperly,asitcouldinterferewiththenormalbehavioroftherestofthesketch.

VisualizingtherecordeddataWearenowgoingtovisualizethedatawerecordedwithXively.YoucangooveragaintothedevicepageontheXivelywebsite.Youshouldseethatsomedatahasbeenrecordedindifferentchannels,asshowninthefollowingscreenshot:

Byclickingononeofthesechannels,youcanalsodisplaythedatagraphically.Forexample,thefollowingscreenshotshowsthetemperaturechannelafterafewmeasurements:

Afterawhile,youwillhavemorepointsforthetemperaturemeasurements,asshowninthefollowingscreenshot:

Youcanalsodothesameforthehumiditymeasurements;thefollowingscreenshotshowsthehumiditymeasurements:

Notethatbyclickingonthetimeicon,youcanchangethetimeaxisanddisplayalongerorshortertimerange.

Ifyoudon’tseeanydatabeingdisplayed,youneedtogobacktotheArduinoIDEandmakesurethattheanswercomingfromtheXivelyserverisa200OKmessage,likewesawintheprevioussection.

SummaryLet’ssummarizewhatwedidinthischapter.WeusedtheEthernetshieldtobuildanInternetofThingsproject,asweconnectedtheEthernetshielddirectlytoacloudservice.WemeasureddataontheArduinoboardandsentthisdatatothecloudserviceXivelysothatitcanbeaccessedanddisplayedfromanywhere.

TheadvantageofthissolutionisthatthedatarecordedonXivelyisaccessiblefromanywhere,andnotonlyfromyourlocalnetwork.YoucanalsousethedataandXivelytocreateautomatedtriggersbasedonthedata.Youcan,forexample,sendarequesttoanotherwebsitebasedontherecordeddata.Youcanalsosharethedatathatisrecordedbyyourdevicewithcolleaguesorfriendssothattheycanalsomonitorwhatyourprojectisrecordinginrealtime.

Ofcourse,oneofthedrawbacksfromthissolutionisthatifyourInternetconnectionisdown,thewholeprojectwon’tworkatall.

Thefollowingwerethemajortakeawaysfromthischapter:

Wefirstbuiltthehardwareofthisproject,includingtheEthernetshieldandtheDHT11sensortomeasuretemperatureandhumidity.Then,wewentovertotheXivelywebsiteandcreatedanaccountthere.WealsosetupadeviceontheXivelyinterface,andcreatedchannelssothatdatacanberecordedontheXivelywebsite.Finally,wealsogotafeedIDandAPIkeysothattheArduinosketchknowswheretosendthedata.WethendesignedtheArduinosketchforthisproject.TheArduinosketchwasresponsibleformeasuringdata,formattingitaccordingtotheXivelyguidelines,andsendingittoXively.WetestedthissketchandmadesurethatXivelyacceptedthedata.Finally,wewentagaintotheXivelywebsitetovisualizethedata.Welearnedhowtovisualizethisdatagraphically,andsawthedataarriveinrealtime.

Inthenextchapter,wearegoingtocontinuebuildingInternetofThingsapplications.WearegoingtouseanotherwebservicecalledTemboo,whichisaplatformthatcanbeinterfacedwithotherservicessuchasGmailorGoogleDocs.WearegoingtousethisservicetorecorddatadirectlyonaGoogleDocsspreadsheetandsendautomatede-mailsbasedontherecordeddata.

Chapter6.LoggingDatainGoogleDocsInthischapter,wearegoingtocontinuebuildingInternetofThingsapplicationsusingtheArduinoEthernetshield.Thistime,wearegoingtousethewebserviceTemboo,tobuildsomeusefulandinterestingapplications.TembooisdifferentfromXively,whichweusedinthepreviouschapter.Itisnotacloudplatforminitself,butitcanbeusedtointerfaceourArduinoprojectswithseveralotherapplicationsandservices.YoucanseeTembooasabridgebetweenyourEthernetshieldandawiderangeofwebservices,suchase-mailservices,textmessagingservices,orstorageservices.

Forexample,inthischapter,wearegoingseehowtointerfaceyourArduinoprojecttoyourGoogleAccountviaTemboo.WewillusethisfunctionalitytoautomaticallylogmeasurementsinsideaGoogleDocsspreadsheet.

TheadvantageofthissolutionisthatyoucanaccessyourGoogleDocsspreadsheetfromanywhere,thusmonitoringyourdatafromanywhereintheworldwhileyourEthernetshieldissendingdatafromhome.Wearealsogoingtosendautomatede-mailalertsusingGmailbasedonthemeasureddata.

Thefollowingwillbethemajortakeawaysofthischapter:

First,wearegoingtoconfigurethehardwarepartofthisprojectusingtheEthernetshieldandtheDHT11sensor.Wearealsogoingtodownloadandinstalltherequiredlibrariesfortheproject,includingtheTembooArduinolibrary.Then,wewillsetupthedifferentaccountsthatweneedforthischapter.First,wewillsetupyourGoogleAccountandcreateaspreadsheetwherethedatawillbelogged.WearealsogoingtosetupaTembooaccountandconfigureittousetheArduinoEthernetshield.Oncealltheaccountsareset,wearegoingtobuildthefirstapplicationofthisproject—automaticlogmeasureddatainaGoogleDocsspreadsheet.Youwillbeabletoseethemeasureddatarecordedliveinthespreadsheetandthedatabeingplottedautomaticallyinrealtime.Finally,wearegoingtosetupourArduinosystemtoautomaticallysende-mailswhenagivenmeasurementexceedsathreshold.

HardwareandsoftwarerequirementsOnthehardwareside,youwillofcourseneedtheArduinoEthernetshieldandanArduinoboardsuchastheArduinoUno.

Youwillalsoneedasensortomeasuresomedata.AsthisbookisabouthowtousetheEthernetshieldandnothowtomeasurefromsensors,youcouldactuallytakeanysensorofyourchoice.

IusedaDHT11sensor,whichisadigitaltemperatureandhumiditysensor.IchosethissensorforthischapterandformanychaptersofthebookasitisaverycheapsensoranditiseasytointerfacewithArduino.AlongwiththeDHT11sensor,youwillalsoneeda4.7kohmresistor.

YouwillalsoneedabreadboardandsomejumperwirestocreatetheconnectionsbetweenthesensorandtheEthernetshield.

Onthesoftwareside,thefirstthingyouwillneedisthelibrarytointerfacewiththesensoryouchosebefore.AsIchoseaDHT11sensorforthisproject,youwillneedtodownloadandinstalltheDHTlibraryfromhttps://github.com/adafruit/DHT-sensor-libraryinordertousethis.

YouwillalsoneedtodownloadandinstalltheArduinoTemboolibraryfromhttps://www.temboo.com/arduino/others/library-installation.

ToinstallanArduinolibrary,simplyunzipthecontentsofthedownloadedfiletoyourlibrariesfolderofyourmainArduinofolder(orcreatethisfolderifitdoesn’texistalready).


https://www.temboo.com/arduino/others/library-installation

HardwareconfigurationIt’snowtimetosetupthehardwareforthisproject.Atthispoint,ifyoufollowedoneofthepreviouschapters,youshouldalreadyhaveyourArduinoEthernetshieldpluggedtotheArduinoboard,oneEthernetcableconnectingtheEthernetshield,andyourInternetrouter.Ifthat’snotthecasealready,pleasedoso.

TheonlythingyouwillhavetoconnectinthisprojectistheDHT11sensorandtheresistor.Youcanhaveanoverviewofthedifferentconnectionsyouhavetomakebylookingatthefollowingschematicdiagram:

First,plugtheDHT11sensortothebreadboard.Then,connectpinnumber1and2ofthesensorusingthe4.7kohmresistor.

Now,wearegoingtoconnectthepowersupply.Connectpinnumber1ofthesensortotheArduino5V,andpinnumber4totheArduinoGND.Finally,connectpinnumber2oftheDHTsensortotheArduinopinnumber7.

Attheend,theconnectionsshouldlooklikethefollowingscreenshot:

Youarenowdonewiththehardwareconfigurationofthisprojectandyoucanmovetothenextstep,thatis,settingupyourGoogleAccountforthisproject.

SettingupyourGoogleAccountForthisproject,youwillneedtohaveaGoogleAccount.IfyouarealreadyusingaservicesuchasGmailorYouTube,itmeansyoualreadyhaveaGoogleAccount,andyouwillbeabletouseGoogleDocsimmediately.Ifthisisnotthecase,youcancreateanaccountatthefollowingaddress:

https://docs.google.com

Onceyouraccountiscreated,youwillbeabletocreateyourfirstspreadsheet.Todoso,justclickontheCreatebuttonandselectSpreadsheet.Youwillhavetoenteranameforthespreadsheet,whichisimportantasyouwillneedtoprovidethisnametoTemboolater.InamedmysheetsimplyEthernet.

Then,youwillneedtogivenamestothecolumnsthatwillreceivethedata.Wearegoingtomeasuretemperatureandhumidityandalsoaddatimestamptoeachmeasurement.Youwillneedtoenterthisinthefirstrow,asshowninthefollowingscreenshot:

WhenyouhaveaGooglespreadsheetthatlookslikethis,itmeansthatyouareallsetupforthispartandthatyoucanmovetothenextpart.

https://docs.google.com

CreatingyourTembooaccountThenextstepistocreateanaccountonTemboo.Todothis,simplygotothefollowingaddress:

https://www.temboo.com/

Youwillbegreetedwithapagethatasksyoutoenteryoure-mailaddress.

Onceyouraccountiscreated,youwillbetakentotheTemboomainpage.Youwillhavemanychoicesatthisstage,buttheonewearelookingforisDevices,whichisdisplayedinthefollowingscreenshot:

Insidethedevicespage,TembooproposesatoolcalledDeviceCoder.ThistoolisintendedtogeneratemostofthecodeforuswhenweuseaplatformsuchastheArduinoYun,orinourcase,theArduinoEthernetshield.

Simplyclickontherightchoice,whichcorrespondstootherArduinodevicessuchastheEthernetshield,asshowninthefollowingscreenshot:

https://www.temboo.com/

Then,youwillbeaskedwhichkindofsensoryouwanttouse.Ofcourse,Temboocannotlisteverypossiblesensorwecoulduseforthiskindofproject.Therefore,theDHT11sensorisnotinthelistofpossibledevices.However,wewillfixthisbyrewritingpartofthegeneratedcode.Fornow,simplychooseGenericsensor.Theninthenextmenu,selectSpreadsheet.

Youwillthenbetakentoanewmenuwhereyoucanconfigureyourdevice.Asthisisyourfirsttimeconfiguringthedevice,youwillbeaskedtocreatenewTemboocredentialsforyourEthernetshield.ATemboocredentialisasetofparametersthatarestoredontheTembooserverssothatyoudon’thavetoenterthemlaterwhiledevelopingyourapplications.

EnterthedetailsaboutyourArduinoboardandEthernetshieldinthecredentialsbox,asshowninthefollowingscreenshot:

Then,justasyouselectedtoworkwithaspreadsheet,youwillalsoneedtoenteryourGoogleAccountcredentials.WewilluseittoaccessGoogleDocsandalsointhefinalpartofthechaptertointerfacewithGmail.

EnterallyourGoogleAccountinformationinthebox,whichisshowninthefollowingscreenshot:

ForthenameofmyGoogleAccountcredential,IusedEthernetGmail.

NotethatifyouhavetheGoogle2-Stepauthenticationmethodactivated,youwillneedtoprovideanapplication-specificpasswordhere.Thisisdoneforsecurityreasons,soyourGoogleAccountdoesn’tgetcompromisedifTemboogetscompromised.Youcanfindmoreinformationaboutapplication-specificpasswordsathttps://support.google.com/accounts/answer/185833?hl=en.

YoucanalsochoosenottoenteryourGoogleinformationatthispoint.However,inthatcase,youwillneedtoenteritinsidetheArduinosketchandmodifythissketchslightly.Tofindmoreinformationaboutthis,youcanvisithttps://www.temboo.com/arduino/yun/update-google-spreadsheet.

Youwillalsobeaskedtogiveanameofaspreadsheetyoupreparedbefore.Simplyenterthisnameinthecorrectbox,asshowninthefollowingscreenshot:

Forexample,InamedmyspreadsheetEthernet:

https://support.google.com/accounts/answer/185833?hl=en

https://www.temboo.com/arduino/yun/update-google-spreadsheet

Afterthat,youwillhavetoselectthedeviceyouwillbeworkingwithtologdatatothespreadsheet.Thisiswhereyouselectthecredentialsthatwecreatedbefore,asshowninthefollowingscreenshot:

YouwillalsoneedtogiveanametotheprojectyoujustcreatedsoyourArduinosketchwilllateronknowwheretosendthedata.InamedminearduinoTemperatureSpreadsheet.Ifyoudecidetouseanothername,youwillhavetomakeasmallmodificationinthecodelater.

Whenthisisdone,youwillbepromptedtodownloadacompressedfilethatcontainstwoArduinocodefiles.Downloadit,unzipit,andhavealookatit.Itwillappearlikethefollowingscreenshot:

ThereshouldbeanArduinofileandanotherfilecalledTembooAccount.h.Thislastfileisthemostimportantasitcontainsyourcredentialsfortheproject.YouwillneedtousethisfilefortherestoftheprojectinplaceofthefilethatisincludedintheGitHubrepositoryoftheproject.

LoggingdatainaspreadsheetAfterfinishingtheconfigurationofourdeviceontheTemboowebsite,wedownloadedabunchoffilesfromTemboo.However,theArduinofilethatwasdownloadedisforagenericsensor.Inthissection,wearegoingtoadaptthisfileforourownneedsandseethedetailsofhowthecodeworks.

NoteYouwillneedtoinsertyourownTembooAccount.hfileinthesamefolderastheArduinofilesothatthecodecanwork.

ThemainArduinosketchforthissectionstartsbyincludingallthelibrariesthatarerequiredfortheprojecttoworkwithTemboo.NotethatwewillalsoinserttheDHTlibrary.Addthefollowinglibrariesinthecode:

#include<SPI.h>

#include<Dhcp.h>

#include<Dns.h>


#include<EthernetClient.h>

#include<Temboo.h>

#include"TembooAccount.h"

#include"DHT.h"

WealsodefinethepinonwhichtheDHTsensorisconnectedandthetypeofthesensor:

#defineDHTPIN7

#defineDHTTYPEDHT11

Then,wewillcreateaninstanceofthesensor:


WealsoassigntheMACaddressoftheEthernetshield.Notethathereitisnotexplicitlyassigned,buttheinformationisdirectlytakenfromyourTembooaccountfile.TheMACaddressisassignedwiththefollowingline:

byteethernetMACAddress[]=ETHERNET_SHIELD_MAC;

WewillalsocreateaninstanceofanEthernetclientasfollows:


Now,inthesetup()functionofthesketch,wewillgetanIPaddressfortheEthernetshieldviaDHCP,asshowninthefollowingcode:

Serial.print("DHCP:");

if(Ethernet.begin(ethernetMACAddress)==0){

Serial.println("FAIL");

while(true);

}

Serial.println("OK");

delay(5000);

StarttheDHTsensorwiththefollowingline:

dht.begin();

Then,intheloop()function,wewillmeasurethetemperatureandhumidityfromtheDHTsensorandconvertthemeasurementstostringswiththefollowingpieceofcode:



inttemperature=(int)t;

inthumidity=(int)h;

Serial.println("Temperature:"+String(temperature));

Serial.println("Humidity:"+String(humidity));

Afterthemeasurementsaredone,wewillcallthefollowingfunctionthatwillactuallyconnecttothewebandlogthedatatoourGoogleDocsspreadsheet.WearegoingtoseethedetailsofthisfunctionthatwasautogeneratedbyTembooinamoment:

runAppendRow(temperature,humidity);

Finally,wewillalsoinsertsomedelaybetweeneachmeasurement.Irecommendusingalargedelay(Ichosetologdataeveryminutefordemonstrationpurposes)becausethenumberofcallsyoucanmaketoTembooislimited.Thedelayisinsertedwiththefollowingline:

delay(60000);

Youcanseethedifferentplansandpricingatthefollowinglink:

https://www.temboo.com/about/plans

Forexample,onthefreeplan,youarelimitedto1,000callspermonth,whichmeansthatyoucanlogmeasurementsapproximatelyevery44minutes.Onthefirstpaidplan,youcanlogonedatapointapproximatelyevery5minutes.Keeptheselimitationsinmindwhiledevelopingyourapplications.

Let’snowseethedetailsoftherunAppendRow()function.ItstartsbydeclaringthetypeofChoreowewanttouse.AChoreoistheequivalentofalibraryontheTembooservice.Forexample,wewilldeclarethatwewanttousethespecificlibrarytoinsertdatainarowintheGoogleDocsspreadsheet:

TembooChoreoAppendRowChoreo(client);

Wewillsetthedifferentinformationaboutyouraccount,suchasthenameoftheaccountandyourappkey.AllthesearealreadydefinedinyourTembooaccountfilethatyoudownloadedbefore,soyoudon’tneedtodefineanythingmore:

AppendRowChoreo.setAccountName(TEMBOO_ACCOUNT);

AppendRowChoreo.setAppKeyName(TEMBOO_APP_KEY_NAME);

AppendRowChoreo.setAppKey(TEMBOO_APP_KEY);

Then,youneedtosomehowspecifywherethedatashouldbelogged.Oncemore,alltheworkisdonebyTemboo:alltheinformationissavedontheTemboosideintheGoogle

https://www.temboo.com/about/plans

Accountcredentialsyouhavesetbefore.IfyouusedthesamenameasIdidforthisexample,youdon’thavetomodifyanythinginthefollowingline:

AppendRowChoreo.setSavedInputs("arduinoTemperatureSpreadsheet");

NotethatthenewwaytoovercometheTemboocalllimitationisalsototransmitseveraldatapointsateachcalloftheTembooAPI,forexample,byappendingseveralrowsateachcall.Youcanmodifythecodeaccordinglyasanexercise.

Now,weneedtoformatthedatasoitcanberecordedcorrectlyinGoogleDocs.Whatyouwanttoinsertinagivenrowisatimestamp,thetemperature,andthehumidity.Forthetimestamp,wearesimplygoingtousethetimethathaspassedsincethedevicewaspoweredonwiththemillis()function.

Thedataitselfwillbecontainedinsideastringvariable,wherethevalueofeachcolumnwillbeseparatedwithacomma,asshowninthefollowingcode:

StringRowDataValue=String(millis())+","+String(temperature)+","+

String(humidity);

AppendRowChoreo.addInput("RowData",RowDataValue);

WealsoneedtosetwhichChoreowewanttousewiththefollowingline:

AppendRowChoreo.setChoreo("/Library/Google/Spreadsheets/AppendRow");

Then,wecanfinallyexecuteChoreoandstoretheresultinavariablecalledreturnCodeusingthefollowingline:

unsignedintreturnCode=AppendRowChoreo.run();

Ifthiscodeisequalto0afterChoreohasbeenexecuted,itmeansthateverythingwentfine,andwewillprintthecorrespondingmessageontheSerialMonitorfordebuggingpurposesusingthefollowingpieceofcode:

if(returnCode==0){

Serial.println("Done!\n");

}else{

//Anon-zeroreturncodemeanstherewasanerror

//Readandprinttheerrormessage

while(AppendRowChoreo.available()){

charc=AppendRowChoreo.read();

Serial.print(c);

}

Serial.println();

}

Ifthat’snotthecase,wewillprintthecorrespondingerrormessageontheSerialMonitor.Finally,wecloseChoreowiththefollowingline:

AppendRowChoreo.close();

NoteYoucanfindallthecodeforthissectionontheGitHubrepositoryofthischapterathttps://github.com/openhomeautomation/arduino-networking/tree/master/chapter6.


EvenifyoudecidetogetthecodedirectlyfromtheGitHubrepository,notethatyouwillneedtotakeyourownTembooaccountfileorenterthecorrectinformationintheTembooaccountfileprovidedonGitHub.

Wecannowtesttheproject.UploadthecodetotheArduinoboard,gotoGoogleDocs,andopenthespreadsheetoftheproject.Afteramoment,youshouldseethefirstmeasurementsbeingloggedinsidethespreadsheet,asshowninthefollowingscreenshot:

YoucanalsousetheintegratedplottingfunctionalitiesofGoogleDocstodisplaythemeasurementsonagraph.Youcansimplyselectthecolumnscorrespondingtothedata(A,B,andCintheexampledevelopedinthischapter),andclickontheInsertChartbuttoninsidethetoolbar.Youwillbepromptedtochoosethetypeofgraphyouwanttoplot.Isimplychosealinecharttoplotallthedataonasinglegraph.Thegraphwilllooksimilartothefollowingscreenshot:

Aseverythingisdynamic,youshouldseethatthegraphisupdatedinrealtimeasnewmeasurementscomein.NotethatasthisisaspreadsheetonGoogleDocs,itisaccessible

fromanywhereyouareintheworld,youjustneedtologintoyourGoogleAccount.

Sendingautomatede-mailsInthislastpartofthechapter,wearegoingtobuildonwhatwealreadydid,butchangetheapplicationslightly.Thistime,wearegoingtousetheEthernetshieldandTembootoautomaticallysende-mailswhenaconditionisreached.Asanexample,wewillsetaconditiononthemeasuredtemperature.Wheneverthetemperaturereachesagivenvalue,wewillsendane-mailtotheaddressofyourchoice,forexample,yourprofessionale-mailtokeepyouupdatedwhenyouareatwork.

ItstartsbygoingagaintotheDeviceCoderontheTemboowebsiteathttps://www.temboo.com/library/Library/Devices/Arduino/Others/.

ClickonGenericsensorandthenonEmail.Thistimeyouwon’thavetoenterthatmuchinformation.YourGmailaccountshouldalreadybesetfromtheprevioussectionandtheDeviceCodershouldautomaticallyselectyourEthernetshield.

Yousimplyneedtoenterthedestinatione-mail(forexample,yourprofessionale-mailaddressorthee-mailaddressfromafamilymember)andtheSubjectfieldofthee-mail.Donotworrynowaboutthevalueofthebodyofthee-mail;wewillchangeitlater:

Whenitisfinished,clickonGenerate.Asfortheprevioussection,youwillbepromptedtoenteranameforthisprojectsothatTembooknowswheretosende-mails.InamedminearduinoTemperatureEmail,butifyoudecidetouseanothername,youwillsimplyhavetochangeonelineinthecodelater.

Youcannowdownloadthegeneratedcode,whichwewillmodifyabit.Asfortheprevioussection,wearegoingtomodifytheArduinocode,butitisimportantthatyougetyourownTembooAcccount.hfilethatcontainstheinformationrelativetoyourownaccountonTemboo.

TheArduinosketchissimilartotheoneintheprevioussection,soIwillonlydiscussthemainchanges.

Intheloop()functionofthesketch,youneedtosetthelimitatwhichthee-mailwillbesentbyTemboo.Fordemonstrationpurposes,Iwillsetthelimitto23,asshowninthefollowingcode:

https://www.temboo.com/library/Library/Devices/Arduino/Others/

if(temperature>23){

Serial.println("\nTriggered!Calling/Library/Google/Gmail/SendEmail…");

//Sendemail

runSendEmail(temperature);

}

Youcanseethateverytimethetemperaturegoesabovethatlimit,analertwillbesentbyTembooviae-mail.Wewillseethedetailsofthisfunctioninamoment.Ialsoinserteda1-minutedelaybetweeneachmeasurement,sowedon’tcontinuouslysende-mailsifthethresholdiscrossed:

delay(60000);

Nowlet’slookatthedetailsoftherunSendEmail()function.ThisfunctionisresponsibleforcreatingthecorrectChoreotosendane-mail,setthebodyofthee-mail,andsenditviaTemboo.

ItstartsbycreatingthecorrectChoreotosendane-mailwiththefollowingline:

TembooChoreoSendEmailChoreo(client);

WealsodefinethedifferentinformationrelativetoyouraccountthatisdefinedintheTembooaccountfileyoujustdownloadedfromTemboo:

SendEmailChoreo.setAccountName(TEMBOO_ACCOUNT);

SendEmailChoreo.setAppKeyName(TEMBOO_APP_KEY_NAME);

SendEmailChoreo.setAppKey(TEMBOO_APP_KEY);

Then,thisiswhereyouneedtoenterthenameofthee-mailprojectthatyoujustcreatedonTemboo.IfyouusethesamenameasIdid,thereisnoneedtomodifyanythinginthefollowingline:

SendEmailChoreo.setSavedInputs("arduinoTemperatureEmail");

Wewillnowbuildthebodyofthee-mail,whichwillbestoredinastringvariable.Wesimplyuseagenericmessagewhereweattachthevalueofthemeasuredtemperatureandstoreeverythinginastring.Finally,wewilladdthefollowinglinesasaninputtotheChoreousedtosende-mails:

StringMessageBodyValue=String("Alert!Thecurrentsensorvalueis:")+

String(sensorValue);

SendEmailChoreo.addInput("MessageBody",MessageBodyValue);

JustbeforeexecutingChoreo,wedefinethatwewanttouseSendEmailChoreofromGmailusingthefollowingline:

SendEmailChoreo.setChoreo("/Library/Google/Gmail/SendEmail");

WecanfinallyexecuteChoreoandstoretheresultinavariable:

unsignedintreturnCode=SendEmailChoreo.run();

Asintheprevioussection,iftheresultis0,itmeanseverythingwentfine.Ifthisisnotthecase,wewillprinttheerrormessageontheSerialportfordebuggingusingthefollowing

pieceofcode:

if(returnCode==0){

Serial.println("Done!\n");

}else{

//Anon-zeroreturncodemeanstherewasanerror

//Readandprinttheerrormessage

while(SendEmailChoreo.available()){

charc=SendEmailChoreo.read();

Serial.print(c);

}

Serial.println();

}

Finally,wewillcloseChoreowiththefollowingline:

SendEmailChoreo.close();

NoteYoucanfindallthecodeforthissectionontheGitHubrepositoryofthischapterathttps://github.com/openhomeautomation/arduino-networking/tree/MASTER/chapter6.

Youcannowtestthesketch.ThefirstthingtodoistomakesurethatyouhaveyourownTembooaccountfileinthesamefolderastheArduinosketch.Then,uploadthesketchtotheArduinoboardandopentheSerialMonitor.Thefirstthingyoushouldseeistheconfirmationmessagethateverythingwentok:

DHCP:OK

Setupcomplete

Then,youshouldseethefirstmeasurementsontheSerialMonitor:

Temperature:21

Humidity:39

Dependingonthetemperaturevalue,youmightneedtopinchyoursensortotriggerthee-mailalert.Remember,intheexampleofthischapter,wesetavalueof23degreesforthetemperature.Afterawhile,ifthetemperaturereachesthethreshold,youshouldseethefollowingmessage:

Triggered!Calling/Library/Google/Gmail/SendEmail…

Afterawhile,thefollowingconfirmationmessageshouldappear:

Done!

YoucannowclosetheSerialMonitorandgocheckthee-mailaccountthatyousetonTemboo.YoushouldhavereceivedamessagewiththetitleyousetonTemboo,andyouwillalsoreceivethebodythatindicatesthegenericmessageyousetinthesketchalongwiththemeasuredtemperature.

https://github.com/openhomeautomation/arduino-networking/tree/MASTER/chapter6

SummaryInthischapter,wecreatedanotherInternetofThingsprojectusingthewebserviceTemboo.BasedonTemboo,webuilttwoexcitingapplications.ThefirstonewastoautomaticallylogmeasurementsinsideaGoogleDocsspreadsheet.Comparedtotheapproachwetookinthepreviouschapter,theadvantagehereisclearlythatGoogleDocsisthewidelyusedstandardtocreateandsharespreadsheets.Youcanaccessyourdatafromanywherejustbyusingawebbrowser,andyoucanalsoplotthedataandshareiteasilywithyourfriendsandfamily.

WealsobuiltanexcitingapplicationwhereweinterfacedourprojectwithGmailviaTemboo.Webuiltanautomatede-mailalertsystembasedonthemeasureddata.

Let’sseewhatthemajortakeawaysofthischapterwere.First,webuiltthehardwareoftheproject,withtheDHT11temperatureandhumiditysensorontopoftheArduinoEthernetshield.

Then,wesetupthedifferentaccountsthatwereneededfortheproject.WefirstcreatedaspreadsheetonGoogleDocsandconfigureditcorrectlysoitcanworkwithTemboo.Then,wealsocreatedaTembooaccountandconfigureditsothatyourEthernetshieldcansenddatatoTembooandlogmeasurementstoGoogleDocs.

Afterthesettingupphase,webuiltthefirstapplicationofthisproject,whichconsistedofloggingdatadirectlytoaGoogleDocsspreadsheet.WealsodisplayedthisdatausingtheGoogleDocsplottingcapabilities.

Finally,weusedTembooagaintocreateanautomatede-mailalertsystembysendingane-mailautomaticallytotheaddressofyourchoicewhenameasurementreachedagiventhreshold.

Asthisistheendofthisbook,let’sseewhatwelearnedabouttheArduinoEthernetshieldandwhatexcitingapplicationswecancreatewithit.

ThefirstpartofthebookwasallaboutrunningawebclientontheEthernetshield.WemadeafirsttestbyjusttryingouttheshieldandseeingwhetheritcouldconnecttotheInternetandgrabthecontentsofapage.Then,webuiltourfirstmeasurementsystem,wheretheEthernetshieldwasconnectingtoaserverrunningtoyourcomputertologsomedata.

Inthesecondpartofthebook,wegavemoreautonomytotheArduinoEthernetshieldbyrunningawebserverrightontheArduinoboard.Wemadethemeasurementprojectagain,butthistimebyhavingawebserverrunontheboardandloggingdatatoaSDcardinsertedintheshield.WealsoconnectedarelaytotheArduinoboardandwecontrolleditviaEthernet.

Finally,webuilttwoInternetofThingsprojectusingtheplatformsXivelyandTemboo.Inboththeseprojects,wesentdatatotheWebusingtheEthernetshieldsothatthisdatacanbeaccessedanddisplayedgraphicallyfromanywhereintheworld.

Toconcludethisbook,Ihopethatalltheinformationyoufoundinthedifferentchapters

willgiveyouthewilltobuildevenmoreexcitingapplications.TheArduinoEthernetshieldisoneofthebestwaystobuildamazingconnectedapplicationswithArduino,andthereisnolimittowhatyoucandowiththeconceptsyoulearnedinthisbook.

IndexA

account,Googlesettingup/SettingupyourGoogleAccount

account,Temboocreating/CreatingyourTembooaccount

application,buildingwithArduinoboardhardwarerequisites/Hardwareandsoftwarerequirementssoftwarerequisites/Hardwareandsoftwarerequirementshardwareconfiguration/Hardwareconfiguration

application,buildingwithArduinoEthernetshieldhardwarerequisites/Hardwareandsoftwarerequirementssoftwarerequisites/Hardwareandsoftwarerequirementshardwareconfiguration/Hardwareconfiguration

Arduinoboardwebserver,creatingon/CreatingawebserveronArduino

ArduinoEthernetShieldURL/Hardwareandsoftwarerequirements,Hardwareandsoftwarerequirements

ArduinoIDEURL/Hardwareandsoftwarerequirements

Arduinolibraryinstalling/Hardwareandsoftwarerequirements

ArduinoTemboolibraryURL/Hardwareandsoftwarerequirementsinstalling/Hardwareandsoftwarerequirements

ArduinoUnoURL/Hardwareandsoftwarerequirements,Hardwareandsoftwarerequirements

automatede-mailssending/Sendingautomatede-mails

BBreadboard

URL/Hardwareandsoftwarerequirements,Hardwareandsoftwarerequirements

CCOMpin,relay/Hardwareconfigurationconnection,ArduinoEthernetShield

testing/Testingyourconnection

Ddata

sending,toserver/Sendingdatatoaserverlogging,onSDcard/LoggingdataonanSDcardplotting/Plottingthedatalocallysending,toXively/SendingdatatoXivelylogging,inGoogleDocsspreadsheet/Loggingdatainaspreadsheet

databaseincomingdata,logginginto/Logincomingdatainadatabase

delay()function/TestingyourconnectionDeviceCoder,Temboo/CreatingyourTembooaccount

URL/Sendingautomatede-mailsDHT11sensorArduinoEthernetShield


DHTlibraryURL/Hardwareandsoftwarerequirements,Hardwareandsoftwarerequirements,Hardwareandsoftwarerequirements

Ee-mails

sending/Sendingautomatede-mailsEasyPHP

URL/Hardwareandsoftwarerequirements

Fflotlibrary


GGNDpin,relay/HardwareconfigurationGoogleAccount

settingup/SettingupyourGoogleAccountGoogleDocs

URL/SettingupyourGoogleAccountGoogleDocsspreadsheet

data,logging/Loggingdatainaspreadsheet

Hhardwareconfiguration

fordata,logginginGoogleDocs/Hardwareconfigurationhardwareconfiguration,ArduinoEthernetShield/Hardwareconfigurationhardwareconfiguration,InternetofThingsproject/Hardwareconfigurationhardwarerequirements,ArduinoEthernetshield/Hardwareandsoftwarerequirementshardwarerequisites

application,buildingwithArduinoEthernetshield/Hardwareandsoftwarerequirementsforbuilding,applicationwithArduinoboard/Hardwareandsoftwarerequirementsforcontrollingobjectsremotely/HardwareandsoftwarerequirementsforInternetofThingsproject/Hardwareandsoftwarerequirementsfordata,logginginGoogleDocs/Hardwareandsoftwarerequirements

Iinputpins,relay

VCCpin/HardwareconfigurationGNDpin/HardwareconfigurationSIGpin/Hardwareconfiguration

InternetofThingsprojecthardwarerequisites/Hardwareandsoftwarerequirementssoftwarerequisites/Hardwareandsoftwarerequirements

JJSONformat

URL/LogincomingdatainadatabaseJumperwires


LLAMP

URL/HardwareandsoftwarerequirementsLINKLED/Hardwareconfiguration

MMAMP

URL/HardwareandsoftwarerequirementsMicroSDcard

URL/HardwareandsoftwarerequirementsMongoDB


NNCpin,relay/HardwareconfigurationNOpin,relay/Hardwareconfiguration

Ooutputpins,relay

COMpin/HardwareconfigurationNCpin/HardwareconfigurationNOpin/Hardwareconfiguration

PPHP

used,forbuildingserver-sideapplication/Logincomingdatainadatabase

Rrecordeddata

visualizing/Visualizingtherecordeddatarelay

testing/Testingtherelaycontrolling,remotely/Controllingtherelayremotelycontrolling,fromdistantlocation/Controllingtherelayfromanywhere

remoteobjects,controllinghardwarerequisites/Hardwareandsoftwarerequirementssoftwarerequisites/Hardwareandsoftwarerequirementshardwareconfiguration/Hardwareconfiguration

resultsdisplaying/Displayingtheresults

runAppendRow()function/Loggingdatainaspreadsheet

SSDcard

data,loggingon/LoggingdataonanSDcardserver

data,sendingto/SendingdatatoaserverSIGpin,relay/Hardwareconfigurationsketch

writing,fortestingArduinoEthernetShieldconnection/Testingyourconnection

softwarerequirements,ArduinoEthernetshield/Hardwareandsoftwarerequirementssoftwarerequisites

forbuildingapplication,withArduinoEthernetshield/Hardwareandsoftwarerequirementsforbuilding,applicationwithArduinoboard/Hardwareandsoftwarerequirementsforcontrollingobjectsremotely/HardwareandsoftwarerequirementsforInternetofThingsproject/Hardwareandsoftwarerequirementsfordata,logginginGoogleDocs/Hardwareandsoftwarerequirements

SQLiteURL/Hardwareandsoftwarerequirements

TTeleduinolibrary

URL/HardwareandsoftwarerequirementsTeleduinoservice

URL/ControllingtherelayfromanywhereTemboo

account,creating/CreatingyourTembooaccountTembooaccount

creating/CreatingyourTembooaccountURL/CreatingyourTembooaccount

TembooAccount.hfile/CreatingyourTembooaccountTimelibrary

URL/LoggingdataonanSDcard

Uupdate()function/Displayingtheresults

VVCCpin,relay/Hardwareconfiguration

WWAMP

URL/Hardwareandsoftwarerequirementswebserver

creating,onArduinoboard/CreatingawebserveronArduino

XXively

data,sendingto/SendingdatatoXivelyXivelyaccount

creating/CreatingyourXivelyaccountURL,forsignup/CreatingyourXivelyaccount

Arduino networking marco schwartz

Education

Transcript of Arduino networking marco schwartz