Download the Session 2 companion slides. - TimeSys

Track OneBuilding a connected home automation device with theDigi ConnectCore Wi-i.MX51 using LinuxLinkSession 2How to build a control application using Qt Embedded for Linuxto design a UI experienceAudio streaming is available for this event.Turn on your speakers to listen.www.timesys.com©2011 Timesys Corp.

2 Tools You Can Use• Q&A• Click on Q&A panel (?) orchat icon in the bottom rightcorner• Type in your question inthe space provided• Click on “Submit”www.timesys.com©2011 Timesys Corp.

3 Tools You Can Use• Polling• The poll will appear onyour screen• Select your answer foreach question• Click on “Submit”www.timesys.com©2011 Timesys Corp.

4 Session Information• You can download the slides for today’s session athttp://www.timesys.com/embedded-linux/training/timesysuniversity/digi_wi-imx51• You can view a recording of today’s session athttp://www.timesys.com/embedded-linux/training/timesysuniversity/digi_wi-imx51• Today’s speakers:Maciej HalaszDirector, Product ManagementTimesysBob BlumenscheidProduct Marketing ManagerDigi Internationalwww.timesys.com©2011 Timesys Corp.

5 Building a Connected Home AutomationDevice• Session 1 – Recording availableHow to assemble and deploy an initial BSP and setupdevelopment environment with the matching SDKhttp://www.timesys.com/embedded-linux/training/timesys-university/digi_wi-imx51• Session 2 – TodayHow to build a control application using Qt Embedded for Linuxto design a UI experience• Session 3 – March 17 @ 1pm ESTHow to integrate a WIFI and Bluetooth functionality with thecontrol application• Session 4 – March 24 @ 1pm ESTHow to optimize, test and integrate the solution for quickdeploymentwww.timesys.com©2011 Timesys Corp.

6 Today’s Agenda• Recap of what we have done so far• Introduction to the ConnectCore Wi-i.MX51• Qt development tools installation/setup• Home Automation Application – GUI development• Add labels, control lights• Add code for a custom widget• Test your application locally• Setup GPIO lines to control two GPIO connectedLEDs (lights in a kitchen and a living room)• Linux kernel and GPIO features• Summarywww.timesys.com©2011 Timesys Corp.

7Session 1 Recapwww.timesys.com©2011 Timesys Corp.

8 What We Have Accomplished So Far• Learned about ConnectCore Wi-i.MX51 LinuxLink –needed for all exercises• Reflected product requirements in Linux BSPand SDK• Built a custom BSP with LinuxLink Web Edition• Experiment on day one with a pre-built starting point• Setup a development environment• System level development and optimizations• Development of a value-add software (applications)• Deployed the system on the target via NFS forfuture development• Transferred images• Configured bootloaderwww.timesys.com©2011 Timesys Corp.

9 Project Requirements (Digi CC Wi-i.MX51)• Graphics• Touchscreen• Applications− Screen calibration− Home automationapplication• Ethernet− Secure Connection− Transfer (FTP/SCP)− Console(Telnet/SSH)• Serial portcommunication• USB− Storage(USB stick)− Extensions• Audio (optional)− Alsa Mixer− Sound playback• Bluetooth− Sensorconnections• GPIOcontrolledLEDs• SD/MMC Card- Filesystem• NAND Flash− Boot from− Additional storage• WiFi− Data upload to aserverwww.timesys.com©2011 Timesys Corp.

10Home Automation Device (Blueprint)Connected Home Automation Control ApplicationUser Interface, Buttons, Lights, etcLightControlAlarmsoundBluetooth SensorWireless DataLoggingMiddlewareLCDcalibrationQt Embeddedsetupscriptsalsa-utilscwiiddbusopensshnetworkingshellalsabluezWireless toolsLinux kernelDriverDriverDriverDriverDriverDriverDriverU-Boot bootloaderDriverDriverWi-i.MX51LCDTouchScreenGPIOAudioUSBBluetoothWiFiEthernetSerialNANDSDIOwww.timesys.com©2011 Timesys Corp.

11Introduction to theDigi ConnectCore Wi-i.MX51www.timesys.com©2011 Timesys Corp.

12 Giveaway• If you attend at least 3 out of4 sessions in our Track 1,we will automatically enter youinto a drawing for a prize.• The winner will receive acomplete ConnectCore Wi-i.MX51Development Kit.• Together with Digi International, we also offer theabove mentioned kit at a discount price of $249+S&H• If interested in buying a kit, send an email tosales@timesys.com with “CC-Wi-i.MX51 Kit SPECIALOFFER” in subject line.www.timesys.com©2011 Timesys Corp.

13Qt Development ToolsInstallation/Setupwww.timesys.com©2011 Timesys Corp.

30 Bulletinself-efficacy and motivates her or him to perform the same tasks. This isespecially true among children who have experienced difficulties in learningskills (Schunk and Hanson, 1985). Moreover, Schunk et al. (1987) andBandura and Menlove (1968) find advantages for multiple peers, presumablyas these increase the probability that observers will perceive themselves assimilar in competence to at least one of the role models. Especially whensubjects doubt their learning capabilities, observation of multiple peerssucceeding may better promote subjects’ self-efficacy (Bandura, 1986). 7,8Given the pupil’s own IQ, the expected number of other pupils in the classwith similar IQ increases with class size. 9 Whether this mechanism indeedexplains a zero net effect of class size reduction can be tested by including thenumber of pupils in the class with similar IQ as an additional regressor in thetest score equations. As the PRIMA data include for each pupil in the sample itsown IQ and the IQ-score of each of its classmates, we are able to construct thevariable ‘‘number of classmates with similar IQ’’. This variable has anexpected value which increases with the size of the class. 10 Our hypothesis isthus twofold: inclusion of this variable should reduce (or possibly even reverse)positive class size effects on achievement, and the new variable should have apositive direct effect on achievement. To make this test operational we havedefined students with similar competence as those in a class that fall within arange of plus or minus half a grade-level standard deviation (+/–2 IQ-points)around the given pupil’s IQ. The correlation coefficient between this variableand actual class size equals 0.46 in grade 4, 0.31 in grade 6, and 0.40 in grade 8.It should also be noted that the number of similar pupils is not a direct measureof class homogeneity. Class homogeneity is best measured by a statistic like thevariance. Although the number of pupils in the class with similar IQ and the7 Another possible mechanism leading to a positive relation between performance and the numberof similar classmates is that teachers may target their instruction to groups of children with similarcompetence. If instruction time is divided in proportion to the size of the group, members of largergroups receive more instruction time.8 In a recent paper Lazear (1999) proposes another peer group mechanism in relation with class sizeeffects. The driving force in his model is the presence of disruptive children who cause negativeexternalities (congestion). To explain our findings, we are, however, in search for a mechanismcausing positive externalities.9 An alternative hypothesis is that children learn from individuals that are smarter than themselves.We tested this hypothesis by including number of students in an individual’s class with an IQ higherthan their own. Even after controlling for pupils’ own IQ, this served merely as a proxy for IQ rankwithin a class producing a large negative effect with no significant decrease in the positive class sizeeffect.10 As mentioned earlier, IQ was measured at the same time as the test scores. Although individualIQ scores have probably been affected by the size of the class, there seems no reason to assume thatclass size affects the number of classmates with similar IQ, in another way than the simple mechanismthat with a larger number of classmates the expected number of similar classmates increases.Notice that with IQ measured afterwards, explicit ability tracking on the basis of measured IQ isprevented.Ó Blackwell Publishers 2002

15Home Automation Application –GUI Developmentwww.timesys.com©2011 Timesys Corp.

16 Home Automation Application• Create a new Workspace• Create a new Qt GUI Project• UI Type - QMainWindow• No additional QT frameworks are necessary• Create the following components• Remove menu bar and status bar• Use layouts• Add labels for Living Room and Kitchen lights and Garage door• Add Qwidget placeholders for buttons• Use Spacers• Custom Widget• Develop or adapt an existing custom widget for a buttonwww.timesys.com©2011 Timesys Corp.

17 Home Automation Application (Cont’d)• Define/Connect signals• Define a signal in a custom widget• Capture the signal in a service class• Implement the service routine• Change the stylesheet of the design• Create a resource file• Add a new JPG with a background• Make your application use your stylesheetwww.timesys.com©2011 Timesys Corp.

18Setup GPIO Lines to ControlTwo GPIO Connected LEDswww.timesys.com©2011 Timesys Corp.

19 SYSFS and GPIO – What Are They?• What is SYSFS• Virtual in-memory file system• Exports information about devices and drivers from the kernel devicemodel to userspace• Used for configuration of GPIO• GPIO-SYSFS• User interface to the in kernel gpio framework• Same interface no matter what platform you're developing for• Deals with pins strictly one at a time• Available in all mainline kernels from 2.6.27 onwardswww.timesys.com©2011 Timesys Corp.

20 How to Control GPIO with SYSFS• Procedure• Find the correct GPIO lines for the two onboard LEDso Use hardware reference manuals• Request the GPIO number from the kernel (73 and 74)# echo 74 > /sys/class/gpio/export• Once you've done this you'll see a folder/sys/class/gpio/gpio74In this folder you'll see the attributes needed to control the gpio.We will use attribute value.www.timesys.com©2011 Timesys Corp.

21 How to Control GPIO with SYSFS (Cont’d)• Procedure• Set the direction for each GPIO by writing one of "in", "out", "high" or"low" to your gpio's direction attribute. "low" and "out" have the sameeffect, to change the pin to an output which is initially low. "high"changes the pin to an output which is initially high. "in" changes thepin to an input.# echo out > /sys/class/gpio/gpio74/direction# cat /sys/class/gpio/gpio74/direction• Control the GPIO state (LED on/off) by writing “0” or “1” to the valuefile# echo 1 > /sys/class/gpio/gpio74/value• Set links for your applicationwww.timesys.com©2011 Timesys Corp.

22Linux Kernel and GPIO Featureswww.timesys.com©2011 Timesys Corp.

23 LinuxLink Architecturewww.timesys.com©2011 Timesys Corp.

24What We Have Accomplishedwww.timesys.com©2011 Timesys Corp.

25 What We Have Accomplished• Learned about ConnectCore Wi-i.MX51 LinuxLink –needed for all exercises• Installed the IDE development tools for Qt design• Developed a GUI with the following:• Layers, Custom Widgets, Spacers and Labels• Implemented signals-handlers• Learned about GPIO and SYSFS• Setup two onboard LEDs for user access• Added code to our application to control the LEDswww.timesys.com©2011 Timesys Corp.

26 Next Session• March 17 @ 1pm ESTHow to integrate a WIFI and Bluetooth functionalitywith the control application• Add libraries to support WIIMOTE features• Enable Bluetooth support in the Linux kernel• Develop code to pair Bluetooth devices, to connect and read valuesfrom accelerometers• Add support for the WIFI – RedPine driver• Add code in the application to periodically log data and upload it to aremote server• More fun to come…www.timesys.com©2011 Timesys Corp.

27 Last Week’s Homework – Share YourExperience1. Outline your own requirements2. Assemble a BSP that matches your needs3. Setup your development environment4. Run your custom Linux images on your hardware• Did you have any problems outlining your requirements and thentranslating them into a Linux blueprint?• How did the assembly of your custom BSP go?• Were you successful in getting your custom Linux images up andrunning on your boards?www.timesys.com©2011 Timesys Corp.

28 Homework1. Design your own GUI with Qt Embedded2. Adapt/design your own QtWidget3. Locate GPIO lines on the board you are using4. Change the state of the GPIO lines from your GUILet us know if you run into any challenges. We have setup a dedicatedcommunication channel to share questions, comments and replies.Please subscribe at https://lists.timesys.com/listinfo/timesys-universityWhile your questions will be answered by Timesys expert engineers,we encourage you to answer questions asked by others. Sharingexperiences is always the best way to learn.www.timesys.com©2011 Timesys Corp.

29 GlossaryLinuxLink (Web Edition) – Web-based version of LinuxLinkLinuxLink (Desktop Edition) – Local version with full customizationand third-party tools integrationWorkorder – Stores definition of your software – filenames, versionsBootloader – Runs first, initializes necessary hardware, loads LinuxLinux kernel – Operating system that manages hardware access andother features for higher level softwareDevice Driver – Code that’s part of a Linux kernel, defines how softwareaccesses specific hardwareFile System – All files (libraries/utilities/scripts/etc.) combined on a singlestorage, e.g. NAND flashMiddleware – Complete frameworks including APIs, utilities that providespecific functionality, e.g. QTAPI (library) – Used by applications, provide functionality, abstracthardware accessToolchain (cross) – The most important part of the developmentenvironment. Used to compile source code into binaries.www.timesys.com©2011 Timesys Corp.