Os Spotlight

Getting started with Android Development • Installing Pepper Flash

Year One Issue #8 Aug 2014

ODROIDMagazine

INTRODUCING THE ODROID-W HARDKERNEL’S MICRO-SIZED PI-COMPATIBLE BATTERY-POWERED WEARABLE COMPUTER! MAKE YOUR OS SPOTLIGHT: OWN ODROID POCKET ROCKET AND COUCH POTATO SMARTWATCH • THE NEXT-GENERATION ODROID-U3+ THE ULTIMATE ANDROID GAMING IMAGE WITH • STEP-BY-STEP BASICS OF LINUX KERNEL COMPILATION 1080P VIDEO PLAYBACK • INSTALL A WEB SERVER WITH NGINX AND LIGHTTPD What we stand for.

We strive to symbolize the edge technology, future, youth, humanity, and engineering.

Our philosophy is based on Developers. And our efforts to keep close relationships with developers around the world.

For that, you can always count on having the quality and sophistication that is the hallmark of our products.

Simple, modern and distinctive. So you can have the best to accomplish everything you can dream of.

We are now shipping the ODROID U3 devices to EU countries! Come and visit our online store to shop!

Address: Max-Pollin-Straße 1 85104 Pförring Germany

Telephone & Fax phone : +49 (0) 8403 / 920-920 email : [email protected]

Our ODROID products can be found at: http://www.pollin.de/shop/suchergebnis.html?S_ TEXT=odroid&log=internal EDITORIAL

ardkernel had a busy month, and released several new products that once again prove that they are the innovative H leaders in ARM micro-computing. Not only has Justin and his team developed a new model for both the U and XU series, but they have also created a tiny wearable Raspberry Pi-compatible product that packs extra features. The ODROID-VU is the USB touchscreen that you’ve been waiting for! A 9-inch model with 10-point multitouch input will be available in the middle of August, and will not only work with the ODROID family of computers, but is also compatible with any Windows, Ubuntu and An- droid machine that supports USB monitors. The ODROID-W is a tiny version of the Raspberry Pi that is intended for embedded, battery-powered applications such as wearables and micro-controllers. It offers many new features not included with the original Raspberry Pi, including removable USB ports, while remain- ing very affordable. And finally, the long-anticipated ODROID-XU3 is now available, and it is the fastest ODROID ever made! It’s got everything the first-generation XU-E offers, with some extra features:

• Samsung Exynos5422 Cortex™-A15 2.0Ghz quad core and Cortex™-A7 quad core CPUs • Mali-T628 MP6 GPU supporting OpenGL ES 3.0/2.0/1.1 and OpenCL 1.1 Full profile • Built-in energy sensors like the XU-E

We’ll be reporting more about the ODROID-XU3 in the October issue, but you can get your XU3 now at the Hardkernel Store at http://bit.ly/1prRcPL. In Linux kernel news, forum user @dsd gives us a report on the newest 3.17 kernel, which appears to now have ODROID support! Follow the original thread at http://bit.ly/1s5Ov7z: “Samsung has been doing a load of work upstreaming ODROID support into official Linux. The first patches will go into Linux-3.17, although a load more patches are needed to make this usable as a desktop system - might take a few more releases before all patches are polished and included. They are also working on upstreaming ODROID support into uboot, and they have a nice feature there, they have found a way to automatically detect X2 vs U2/U3 (by checking for the extra LED on the X2). So now uboot will automatically pick the right device tree to load. That means one appropriately crafted “OS image” will work for X2, U2 and U3.” This issue has lots of information for hardware enthusiasts, including an in- depth look at the different types of eMMC modules that Hardkernel makes and a hands-on look at the powerful ODROID-SHOW. We also feature a guide to compiling your own kernel directly from the Hardkernel GitHub repository, a tutorial for installing the light-weight Nginx web server on an ODROID, Nanik begins his fascinating series on Android Application Development, and more!

ODROID Magazine, published monthly at http://magazine.odroid.com/, is your source for all things ODROIDian. Hard Kernel, Ltd. • 704 Anyang K-Center, Gwanyang, Dongan, Anyang, Gyeonggi, South Korea, 431-815 Makers of the ODROID family of quad-core development boards and the world’s first ARM big.LITTLE architecture based single board computer. Join the ODROID community with members from over 135 countries, at http://forum.odroid.com/, and explore the new technologies offered by Hardkernel at http://www.hardkernel.com/. STAFF

ODROIDMagazine

Rob Roy, Bo Manuel Chief Editor Lechnowsky, Adamuz, Editor Spanish I’m a computer Editor programmer liv- I am President of ing and working in Respectech, Inc., a I am 31 years old and San Francisco, CA, de- technology consultancy live in Seville, Spain, and signing and building web applica- in Ukiah, CA, USA that I founded in was born in Granada. I have recently tions for local clients on my network 2001. From my background in elec- become a father, and my son is now 5 cluster of ODROIDs. My primary tronics and computer programming, I months old. It is an incredible experi- languages are jQuery, Angular JS manage a team of technologists, plus ence! A few years ago I worked as a and HTML5/CSS3. I also develop develop custom solutions for compa- computer technician and programmer, pre-built operating systems, custom nies ranging from small businesses to but my current job is related to quality kernels and optimized applications worldwide corporations. ODROIDs are management and information technol- for the ODROID platform based one of the weapons in my arsenal for ogy: ISO 9001, ISO 27001, and ISO on Hardkernel’s official releases, for tackling these projects. My favorite de- 20000. I am passionate about comput- which I have won several Monthly velopment languages are Rebol and Red, er science, especially micro computers Forum Awards. I use my ODROIDs both of which run fabulously on ARM- such as the ODROID, Raspberry Pi, for a variety of purposes, including based systems like the ODROID-U3. etc. My other great hobby is mountain media center, web server, applica- Regarding hobbies, if you need some, biking, and I occasionally participate in tion development, workstation, and I’d be happy to give you some of mine semi-professional competitions. gaming console. You can check out as I have too many. That would help my 100GB collection of ODROID me to have more time to spend with my software, prebuilt kernels and OS wonderful wife of 23 years and my four images at http://bit.ly/1fsaXQs. beautiful children.

Nicole Scott, Bruno Doiche, Art Editor Art Editor

I am currently a Is enjoying his time Digital Strategist off on vacation for and Transmedia the month of August. Producer who specializ- es in online optimization and inbound marketing strategies, social media di- recting and team coordination, as well as media production for print, TV, film, and web. I also have experience in graphic and website design, social networking management and advertis- ing, video editing and DVD authoring. I own an ODROID-U3 which I use to run a sandbox web server, live in the California Bay Area, and enjoy hiking, camping and playing music. Check out my web page at http://www.ni- colecscott.com. INDEX ANDROID DEVELOPMENT - 6

MOUNT YOUR INTERNAL SD CARD - 9

INTRODUCING THE ODROID-W - 10

SEARCH WITH GOOGLE BBS / FIXING ANDROID OVERSCAN - 14

ALL ABOUT HARDKERNEL’S EMMC MODULES - 15

LINUX KERNEL COMPILATION - 17

YOUTUBE PLAYER ALTERNATIVE - 21

INTERESTING LINUX COMMANDS PART 1 - 22

ODROID U3 VS ODROID U3+ - 23

INSTALL A HOME WEB SERVER - 25

INTERESTING LINUX COMMANDS PART 2 - 25

ODROID-VU AFFORDABLE 9” USB HDMI TOUCH SCREEN - 30

PEPPERFLASH CHROME PLUGIN FOR LUBUNTU 14.04 - 32

ANDROID GAMING: MUPEN64PLUS - 33

IO SHIELD DEMYSTIFIED - 34

DIGGING (INTO) THE ODROID-SHOW - 36

OS SPOTLIGHT: POCKET ROCKET AND COUCH POTATO - 41

MEET AN ODROIDIAN: BO LECHNOWSKY - 47 ANDROID DEVELOPMENT ANDROID DEVELOPMENT: USING THE LINUX KERNEL A GUIDE TO THE ANDROID-SPECIFIC DRIVERS by Nanik Tolaram

inux is the heart of Android, and it depends heavily on it for its op- Leration, and without it Android would not be able to run. However, Android does not use a “plain vanilla” Linux kernel, which means you cannot download a kernel from www.kernel.org CONFIG_ANDROID=y and immediately use it to run Android. CONFIG_ANDROID_BINDER_IPC=y There are a number of drivers, code and CONFIG_ANDROID_LOGGER=y configuration options to be added in or- CONFIG_ANDROID_RAM_CONSOLE=y der for Android to work properly, and CONFIG_ANDROID_RAM_CONSOLE_EN- this article will walk through those spe- ABLE_VERBOSE=y cific drivers and configuration, as well CONFIG_ANDROID_RAM_CONSOLE_ER- as discuss the drivers that are needed ROR_CORRECTION=y to ‘Android’-ify the Linux kernel upon CONFIG_ANDROID_RAM_CONSOLE_ER- which the Android framework depends. ROR_CORRECTION_DATA_SIZE=128 Most of the driver code that needs to be CONFIG_ANDROID_RAM_CONSOLE_ER- added is located inside the kernel/driv- ROR_CORRECTION_ECC_SIZE=16 ers/staging/android folder as can be CONFIG_ANDROID_RAM_CONSOLE_ER- seen in Figure 1. ROR_CORRECTION_SYMBOL_SIZE=8 Figure 1 – Driver list inside the /staging/ There are also a number of drivers CONFIG_ANDROID_RAM_CONSOLE_ERROR_ android directory that are located outside the base direc- CORRECTION_POLYNOMIAL=0x11d tory that are already /staging/android CONFIG_ANDROID_TIMED_OUTPUT=y binder.c in the Linux Kernel mainline. This ar- CONFIG_ANDROID_TIMED_GPIO=y ticle is by no means an exhaustive list for CONFIG_ANDROID_LOW_MEMORY_ The binder driver is the main back- all of the drivers needed, but is a good KILLER=y bone driver for applications in Android, starting point to get a better understand- CONFIG_ASHMEM=y ing of the different drivers needed for and is the gatekeeper of communication Android. If you look inside the Makefile, which between different processes that are running, written in native (C/C++) or Java. Below are the configuration options is located inside the drivers/staging/ Without this driver, Android applica- that need to be included as part of the android directory, you will see the ker- kernel zImage. The following configura- nel drivers that are specific to Android. tions will not work at all, since it mounts tion is taken from the file odroidu_an- In the following sections we are going to the essential /dev/binder virtual filesystem. Android uses the binder driver droid_defconfig inside thekernel/ take a closer look at the different driv- extensively, and because applications arch/arm/configs folder, as shown in ers inside this directory, starting with the the following table. binder driver. utilize this framework, any application is indirectly reliant on the binder driver. ODROID MAGAZINE 6 ANDROID DEVELOPMENT

early suspend drivers work together as one unit to manage power resources in an Android device. The sample screenshot shows the content of the wakelock virtual filesystem inside the Nexus 7. Example odroidu_android_defconfig configuration ram_console.c ashmem.c quest certain services that use always-on Location: /kernel/mm/ hardware so that they still operate when The RAM console drive can be la- the device goes to sleep in order to con- belled as a Linux log helper driver. Its The name ashmem stands for An- serve battery power. function is to save the content of the droid Shared Memory, and as the name The wakelock driver is built on top of implies, is a driver that facilitates mem- Linux power management driver. Linux ory sharing between processes , nd pro- provides power management functions vides a mechanism for Linux to reclaim such as suspend and resume, where it al- memory if it finds itself under memory lows the device to be ‘suspended’ by run- pressure. Ashmem makes the /dev/ash- ning on a low power mode, or ‘resumed’ mem directory available for applications by coming back from sleep. The wake- to access its functionality. lock driver is a communication mecha- The driver works using a file descrip- nism allowing user space applications tor which can be shared by processes by and system tasks to determine whether Ashmem pinning and unpinning utilizing the binder driver that was dis- the device is allowed to go to suspend flowchart cussed previously. The unique character- mode. The driver will not suspend the istic of ashmem is that when the process device if there are active wakelocks in the Linux log to a different memory loca- dies, the memory goes with it, so there system. tion before the device reboots. The will not be any orphaned memory. It is Imagine if you are running a music content of the Linux log (which nor- also smart enough to allow applications player on your mobile phone and the mally is accessed using dmesg) can be to specify which memory area can be re- system decided that it’s time to suspend, viewed after reboot in the /proc/last_ claimed or not, which is known as un- your music player stopped playing. Or, kmsg virtual file system. If the device pinning and pinning. imagine if the system is about to suspend shuts down completely with no power In order to save memory space, the and there is an incoming phone call, but supplied to it, the last Linux log will unpinned pages are periodically re- you can’t receive it since the system is not be stored the next time you startup claimed by using the LRU algorithm. in the process of suspending. Wakel- the device. This is because the device Ashmem has its own shrinker that is ock makes it possible to avoid the above is completely shut down and there is called when available memory gets low. described scenarios, allowing you to use no power to retain the content of the The normal use case on using ashmem is your device without having to worry memory. As long as there is power sup- shown in the float chart in Figure 3, to when it will go to suspend mode. The plied to the device, the next time you the bottom-right. wakelock driver introduced a new virtual restart, you will be able to extract the filesystem called/proc/wakelocks . last Linux log through the last_kmsg wakelock.c Power management, wakelock and virtual filesystem. This driver is very Location: /kernel/power Figure 3 – Ashmem regions This is the a controversial driver that started the heated discussion between the Android kernel team and Linux kernel developers back in the days when Google had just starting committing its code for the mainline kernel, and was considered by purists to be a hack. This driver gives userspace applications the ability to re-

ODROID MAGAZINE 7 ANDROID DEVELOPMENT ANDROID DEVELOPMENT

hit, which means that only when the memory falls to the lowest free memory available than the application will be killed. The following table lists the different value that the framework will use to assign to launched process:

HIDDEN_APP_MAX_ADJ HIDDEN_APP_MIN_ADJ SERVICE_B_ADJ PREVIOUS_APP_ADJ HOME_APP_ADJ SERVICE_ADJ BACKUP_APP_ADJ HEAVY_WEIGHT_APP_ADJ The wakelocks drivers area considered a Google hack by purists PERCEPTIBLE_APP_ADJ VISIBLE_APP_ADJ FOREGROUND_APP_ADJ useful for troubleshooting issues such into different categories: main, events, PERSISTENT_PROC_ADJ as kernel panic, out of memory or any radio and system. The following vir- SYSTEM_ADJ other kind of problem that causes a tual filesystem are made available from MIN_HIDDEN_APPS kernel panic. the driver: Internally, the driver only accomo- earlysuspend.c /dev/log/system dates a maximum of 6 different values, Location: /kernel/power /dev/log/radio so the framework does an internal con- /dev/log/events version to fit it to the available slots. You can see this driver in action /dev/log/main The different values can be found in when you leave your device inactive the /sys/module/lowmemorykiller/pa- for few minutes and the screen turns Android provides a log viewer ap- rameters/adj virtual filesystem. off by itself. It’s responsible for mak- plication called logcat that allows The settings of free available mem- ing sure all the necessary components us to view the log in a more hu- ory threshold are linked in a 1:1 ratio inside your device are ‘suspended’ man readable format. The screen- with the adj value, and it is stored in to conserve energy. This driver and shot shows a sample of the content the /sys/module/lowmemorykiller/pa- wakelock go hand-in-hand. It relies of the /dev/log/radio in its raw rameters/minfree virtual filesystem. on Linux’s power management driver, form, which is not very easy to read The minfree value is in pages of 4k. and can be triggered by sending state For example, if it says the free memory information to the following /sys/ lowmemorykiller.c is 8192, it means (8192 * 4k) = 32768 power/state filesystem. which converts to 32KB (32768 / If you have root access to your de- This driver takes care of killing pro- 1024). vice, you can trigger the early suspend cesses from memory when the amount The way in which the minfree by executing the following command: of free memory hits a certain threshold. threshold is mapped with the value Every time an application is launched, from adj is explained in this chart: echo mem > /sys/power/state it is assigned a value to indicate what kind of application it is. This ‘marker’ Minfree threshold mapped with adj value will indicate to the driver whether this logger.c process can be killed. adj minfree As an example, looks at the phone 0 8192 The logger driver is the central log- application that you use to receive and 1 10240 ging driver used by Android system, make calls. The application will be 2 12288 which is also made available to user ap- ‘marked’ to a value that indicates to 4 14336 plications via the built-in logger API. the driver to kill the application only 9 16384 15 20480 Internally, the driver splits the logging when the last low memory threshold is ODROID MAGAZINE 8 ANDROID DEVELOPMENT TIPS AND TRICKS

MOUNT YOUR INTERNAL SD CARD WHEN BOOTING FROM EMMC IN LINUX by @gripped and Rob Roy

hen booting from an eMMC module, the SD card slot W can be used for extra storage instead of a USB drive. To begin, insert a EXT4-formatted SD card, then turn on the ODROID and boot up your favorite Linux distro. Note that since the SD slot is not hot-pluggable, the card needs to be inserted before the system is booted. Type the following into the Terminal window in order to determine the device name for the SD card:

Snapshot of the output of typing cat /dev/log/radio in Terminal $ sudo fdisk -l Device Boot Start ... /dev/mmcblk0p1 8192 ... What the mapping means is that if timed GPIO drivers registration as /dev/mmcblk1p1 8192 ... the free memory threshold is less than they happen. The timed_gpio is one of On an X2 or U3, the /dev/ 20480 (20480 x 4k = 80k), the driver the drivers that register itself to timed_ mmcblk0 device is the SD card, and will start killing processes which have output, and the other is the vibration /dev/mmcblk1 is the eMMC module, value of 15 and above. The same thing driver. As you may have guessed, the but on an XU they are reversed. To happens when the free memory avail- vibration component is responsible for mount the SD card, substitute your able is less than 8192 (8192 x 4k = making your phone vibrate. username and device name in the fol- 32k). In that case, any process that has lowing sample script: value larger than 0 will be killed. alarm-dev.c Location: /kernel/drivers/rtc $ cd ~ $ mkdir sdcard timed_gpio.c / $ sudo mount /dev/mmcblk0p1 \ timed_output.c The alarm driver relies on high res- /home/USERNAME/sdcard olution timer infrastructure provided $ sudo chown USERNAME:USERNAME These combo drivers are use for in Linux. The driver has got its own Now you can store your data in driving a particular GPIO hardware virtual filesystem,/dev/alarm , that is /home/USERNAME/sdcard and it pins for a certain period of time, and is used by the user application to com- will reside on the SD card instead. made available to give code running in municate with the driver. This technique can be used to mount userspace access to the GPIO pins. In This driver is tied to the wakelock the SD card at any location, including order to use this driver, you must know functionality, allowing the alarm to /var/www for a web server. which pin you want to drive, high or continue working even when the de- To automatically mount the SD low signal, and for how long. In device is in sleep mode, which is the sole card at boot, add a line to /etc/fstab by vices that have this driver enabled, it reason why the alarm driver exists. It substituting the device and username: exposes the /sys/bus/platform/driv- provides the alarm management that is # should be on a single line ers/timed-gpio virtual filesystem. used in our user applications or frame- /dev/mmcblk0p1 The timed_gpio depends on anoth- work, in order to support key services. /home/USERNAME/sdcard ext4 er driver called timed_output, where Next month, we’ll take a look in- defaults,noatime,nobootwait its main function is to keep track of side the Android APK file. 0 2

ODROID MAGAZINE 9 ODROID -W INTRODUCING THE ODROID-W A MINIATURE RASPBERRY PI-COMPATIBLE WEARABLE COMPUTER by Justin Lee

he ODROID-W is a miniature wearable comput- Ting module which is ful- An early revision of the ODROID-W, which ly compatible with all software • DC/DC step-up converter was nicknamed the ODROID-Pi available for the Raspberry Pi (RPi). for 5Volt rails (USB host and HDMI) from a Li-Polymer bat- The W stands for: tery

Wearable device development • USB Host port can be placed on top or bottom as preferred Widely applicable Internet of Things (IoT) development • DIY friendly 100mil/2.54mm pitch GPIO ports (up to 32 Workable DIY electronics prototyp- ports) for handy prototyping ing The ODROID-W = RPI + RTC + ADC + UPS + Battery Gauge with significant The ODROID-W measures a very minimalism. small 60 x 36 x 7mm (2.4 x 1.4 x 0.3”).

It also includes many new features and Development History improvements over the original Pi:

• Li-polymer rechargeable battery In early 2014, we had an important charger and fuel gauge circuit project with our partner companies to for wearable and robotics ap- help them with prototyping a few wear- plications able & Internet of Things (IoT) devices. The ODROID-W adds extra features to We first considered using the a fully compatible Raspberry Pi clone • Real Time Clock (RTC) to ODROID-U3 as a base platform. Al- keep accurate time without an though the ODROID-U3 is 8~12 times cessory possible, we decided to make Internet connection by adding a faster than the Raspberry Pi, the power our own (tiny) version of a Raspberry coin battery consumption of the U3 isn’t suitable for Pi, which allows full use of many widely wearable devices like watches or necklac- available Pi peripherals such the Pi Cam- • 12-bit precision ADC to mea- es. We even considered using the Rasp- era module connector and 26-pin GPIO sure the dynamic voltage signals berry Pi itself due to the lower power report. The HDMI port and SD slot were via two single-ended inputs quirements and nice Linux BSP support, changed to micro-sized connectors, and • DC/DC step-down converters but the PCB of the RPi was huge (much the MIPI DSI port was removed due to for higher power efficiency bigger than the ODROID-U3). limited PCB space. In addition to its To create the smallest wearable ac- smaller size, the ODROID-W maintains

ODROID MAGAZINE 10 ODROID - W

This prototype of a U3 smartwatch required too much power. Side-by-side size difference comparison between the Raspberry Pi and the ODROID-W without the USB attachment

Processor: Broadcom BCM2835 ARM11 700Mhz

Memory: Samsung 4Gbit (512MB) LPDDR2 SDRAM

The Raspberry Pi smartwatch was far PMIC: Ricoh RC5T619 includes too big to be viable. DCDCs, LDOs, ADCs, RTC, Battery charger and Fuel gauge Top view of Rev. 1 ODROID-W board full compatibility with all existing Rasp- berry Pi software and peripherals. DCDC: TI TPS61259 is 5V step-up The first sample ODROID-W PCB DCDC for USB host and HDMI was designed on April 14, 2014, and had block a few jumper wires. The second run was designed on May 19, 2014, which cor- Video output: HDMI type-D rected some of the electronics designs (Micro-HDMI) and added an eMMC module socket for test purposes, even though the eMMC is USB: High-speed USB 2.0 host not much faster than SD card due to the GPIO connectors: Rasperry Pi-com- Bottom view of Rev. 1 ODROID-W board slow eMMC host speed in the SoC. In patible 13x2-pin header on the top testing the eMMC speeds, we discovered side as well as bottom side for 2-way only ~10% improvement. The third stacking 20+6 pin header for addition- sample (rev 0.3) was thoroughly tested, al GPIO/RTC/USB connection. and is ready for mass production. The unit price for the ODROID-W GPIOs: A total of 32 GPIOs and 2 is US $30 and it will be available for ADCs are available. purchase from the Hardkernel Store at http://www.hardkernel.com. Camera connector: 15pin MIPI-CSI2 Top view of Rev. 2 ODROID-W board We didn’t follow the instructions care- Memory card slot: Micro-SD (T- Flash) fully enough and got this instead. Power: Micro-USB socket for 5V input. Li-Polymer battery connector (Molex 53398-0271)

RTC Power: Backup battery connector (Molex 53398-0271)

Overall PCB Dimensions: 60 x 36 mm Bottom view of Rev. 2 ODROID-W board

ODROID MAGAZINE 11 ODROID -W

Closeup detail of ODROID-W with Docking Board and LCD

The Docking Board accessory, which attaches to the ODROID-W on either the top or bottom, offers 4 USB host ports and an Ethernet port. You can also choose a 320x240 QVGA TFT LCD-included version. Please watch our Youtube video of the ODROID-W Docking Board at http://bit.ly/1rII5Li for a live demonstration of the board’s capabilities. The base price for the Docking Board is $20, and the TFT LCD-included version is $30. The schematic diagram for the ODROID-W PCB The PCB schematic for the ODROID-W is shown to the right for reference.

DIY Smartwatch Example

This DIY smartwatch has some limited but very cool features, and is intended to be tightly coupled with your Android smartphone via Blu- etooth. Whenever a message arrives on your phone, a notification is sent to the watch, as seen in our video at Hardware materials for assembling the Odroid-W smartwatch http://bit.ly/1sOkTOC.

The following page illustrates how to assemble your very own fashionable smartwatch from an ODROID-W! For detailed schematics and software links, please refer to the original post at http://bit.ly/1rYW8LR.

ODROID MAGAZINE 12 ODROID - W

Smartwatch Assembly

Solder a disassembled USB Bluetooth module and a few buttons. Place double-sided tape on the LCD and on the ODROID-W PCB.

Stack the battery and LCD on the ODROID-W PCB Connect the TFT LCD module with several wires. with double-side tape as shown above.

Assemble the watch straps. Please note that the hinge holders Final assembly of ODROID smartwatch with screen attached. should be soldered first.

ODROID MAGAZINE 13 TIPS AND TRICKS ODROID -W

SEARCH WITH Software GOOGLE BBS • Debian (Raspbian) OS is run- WHAT IF GOOGLE ning on the Linux Kernel 3.10. WERE INVENTED IN • LXDE X11 window manager THE 1980S ? (This can be removed if you want) by Rob Roy • Qt 4.8.4 framework library or a retro-style Google experience, visit the Google BBS at http://bit.ly/1iXk8yF. Don’t • Qt application to display the F clock and SMS / Mail / Call forget to bring your moon boots and walkman! notification

• Android application software • Micro-HDMI cable (written in Java) to push the notification to the smartwatch • Micro-USB cable from a smartphone • 5V/2A Power supply for the The full source code will be released Docking board, which is via Github at http://www.github.com/ required only when the USB hardkernel. devices need 600mA or higher.

FIXING Official accessories • ODROID-VU (9-inch ANDROID 1280x800 TFT HDMI • Docking board with TFT LCD monitor with touch screen) OVERSCAN • Docking board without TFT Summary A SIMPLE APP TO LCD CHANGE THE This tiny version of the Raspberry Pi • Connector package (26-Pin can run a full Raspbian desktop environ- DESKTOP header, 26-Pin header socket, ment on its own, or be used in conjunc- RESOLUTION 20-Pin header socket, 7-Pin header socket and USB host tion with pre-existing and widely avail- by Rob Roy right-angle type) able Pi hardware to create an extremely portable yet powerful computing solu- ugalabs offers an Android app • RTC Backup battery (CR2032 tion, perfect for wearable applications. from the Google Play store with Molex 51021-0200 wired Please post any questions that you may L that can change the resolution connector) have to the ODROID forums at http:// of the desktop in order to fix HDMI forum.odroid.com. monitor overscan issues. For more • Lithium Polymer battery details, please visit its Google Play (3.7V/720mAh with Molex Store page at http://bit.ly/XYfZ51. 51021-0200 wired connector)

• Micro-SD 8GB(UHS-1 class) card of Raspbian with RTC/ PMIC device driver patch

• RTL8188CUS based USB WiFi module To submit your own ODROID-based project for publication, send an email • 720p USB Webcam to odroidmagazine(at)gmail.com.

ODROID MAGAZINE 14 EMMC MODULES ALL ABOUT HARDKERNEL’S EMMC MODULES THE ODROID ADVANTAGE Hardkernel’s removable clip eMMC modules, which are by Justin Lee usually soldered into the board, are unique to ODROIDs.

he Exynos-4412 CPU includes 330MB/sec of host bus bandwidth by a few USB memory card readers. So it an eMMC 4.41 compatible host DDR. is worthwhile to check the compatibility Tcontroller, with a maximum bus We’ve been selling 2 different eMMC list at http://bit.ly/1nPBE4i. speed limited to 100MB/sec, an actual modules: The Green or Blue PCB has The chart on the following page is the clock speed of 48Mhz with DDR. The the eMMC 4.5 chips. full list of eMMC modules we are selling ODROID-X, X2, U2, U3, Q and Q2 The Red PCB has the eMMC 5.0 now. The round label indicates the OS are all based on the Exynos-4412 CPU. chips. The eMMC 5.0 chip is slightly and capacity. The Exynos-5410 CPU, which is smaller but it has the same BGA array The eMMC 4.5 Blue(or Green) used by the the ODROID-XU, XU+E size, so that we can keep using the same PCBs will be obsolete soon except for and XU-Lite, includes an eMMC 5.0 PCB. 8GB models. compatible host controller. However, Most eMMC manufactures are mov- Even you have a different or the hardware design was unable to sup- ing to eMMC 5.0. So it is hard to pur- wrong eMMC, you can use it for port the eMMC 5.0 HS400 mode, be- chase the eMMC 4.5 chips anymore ex- your ODROID if you install a cause there was no public specification cept for the lower capacity like 4GB and proper boot loader and OS image. of eMMC 5.0 when we designed the 8GB. Recently, we started using 16GB ODROID-XU. As a result, all the XU and 32GB eMMC chips from Sandisk Reference series have the eMMC 4.5 (HS200) while we keep buying 8GB and 64GB specification which reaches a maximum eMMC from Toshiba. The eMMC board schematics speed of 160MB/sec since the actual When you install a new OS image http://bit.ly/1p4TX6N clock speed is 160Mhz with SDR. onto the eMMC module, you need a The Exynos-5422 CPU also has an USB memory card reader and an eM- The reader board schematics eMMC 5.0 compatible host controller. MC-to-MicroSD converter board (read- http://bit.ly/1p9j0Z3. The ODROID-XU3 is based on Exynos- er board). Please refer to the images be- 5422 and supports the eMMC HS400 low to understand how to use it. The following page is a handy guide to all mode. The actual clock is 166Mhz and The reader board can’t be detected by of Hardkernel eMMC modules!

The eMMC reader attaches to the Top view of eMMC reader and eMMC mod- Bottom view of eMMC reader and eMMC eMMC module with a small clip ule inserted into SD card reader module inserted into SD card reader

ODROID MAGAZINE 15 EMMC MODULES

EMMC MODULE REFERENCE CHART

ODROID MAGAZINE 16 LINUX KERNEL LINUX KERNEL COMPILATION GET FULL CONTROL OF YOUR OPERATING SYSTEM LIKE A LINUX JEDI by Venkat Bommakanti

s you make progress in using $ uname -a $ cat /etc/os-release Linux, it is inevitable that you would want to tweak your setup A Linux u3-2 3.8.13.26 #1 SMP PRE- NAME=”Ubuntu” in order to accommodate changes in EMPT Wed Jul 9 22:14:37 UTC 2014 VERSION=”14.04, Trusty Tahr” your hardware setup, such as integrating armv7l armv7l armv7l GNU/Linux ID=ubuntu an external device. Such tasks usually re- ID_LIKE=debian quire modifications to the Linux kernel This output indicates the image used PRETTY_NAME=”Ubuntu 14.04 LTS” or linking to a new driver. This article is based on the 3.8.y.z kernel, built on VERSION_ID=”14.04” provides details on starting with natively Wed Jul 9 22:14:37 UTC 2014. HOME_URL=”http://www.ubuntu.com/” building a pristine kernel using only the You can get additional image infor- SUPPORT_URL=”http://help.ubuntu. ODROID itself. This article does not mation using the following commands com/” address cross-compiling, which relates and observing the output: BUG_REPORT_URL=”http://bugs. to building an ODROID kernel using a launchpad.net/ubuntu/” secondary host machine such as an x86. $ cat /proc/version Linux version 3.8.13.26 (root@ After installing a newly built kernel, Requirements THEserver) (gcc version 4.7.2 the above information is useful for com- (crosstool-NG 1.17.0) ) #1 SMP parison when verifying that the kernel 1. Any ODROID board, with an ap- PREEMPT Wed Jul 9 22:14:37 UTC has actually been updated. propriate power adapter. 2014 2. A bootable 8+ GB MicroSD card or Preparing the system eMMC module containing the latest Lubuntu image available from the $ cat /etc/lsb-release Prior to building a kernel, you would Hardkernel website. DISTRIB_ID=Ubuntu 3. A network where the device has ac- DISTRIB_RELEASE=14.04 need to setup the appropriate software cess to the Internet and the ODROID DISTRIB_CODENAME=trusty environment. First, launch a terminal forums. DISTRIB_DESCRIPTION=”Ubuntu 14.04 session and switch to the root user, using 4. Optional SSH access to the U3 via LTS” the command: utilities like PuTTY (MS Windows 7+) or Terminal (Mac, linux to perform the $ lsb_release -a $ sudo -s steps from a remote host computer.

No LSB modules are available. All build related activities need to be System basics Distributor ID: Ubuntu performed by the root user, which can Description: Ubuntu 14.04 be enabled with the su command after Initially, for reference, it is a good LTS typing the root password. idea to note the version of the initial ker- Release: 14.04 Install the initial set of needed com- nel version included with the installed Codename: trusty ponents, using the following installation image with the following command: command:

ODROID MAGAZINE 17 LINUX KERNEL

# apt-get install build-essential # gcc --version # git --version libqt4-dev perl python git gcc-4.8.real (Ubuntu/Linaro git version 1.9.1 4.8.2-19ubuntu1) 4.8.2 Enter Y to accept proposed option, Copyright (C) 2013 Free Software Fetch the and allow for the command to com- Foundation, Inc. source code plete. This is free software; see the source for copying conditions. Create a temporary directory in your This is a comprehensive version of the There is NO home directory and navigate to it using command, highlighting all components warranty; not even for MERCHANT- the commands: required for building a kernel. Some of ABILITY or FITNESS FOR A PARTICU- the required components may already be LAR PURPOSE. # mkdir hk-src installed in your present image, which # cd hk-src will not be affected by the above com- # pkg-config --modversion QtCore mand since only missing components 4.8.6 Your copy of the downloaded source will be installed. code will reside here. Hardkernel uses # perl --version GitHub for the source-control of its The installation output may suggest open-source software for U3. additional optional components. Al- This is perl 5, version 18, sub- though not mandatory, you may install version 2 (v5.18.2) built for Use the following command to check those using the component list, like arm-linux-gnueabihf-thread-multi- out the 3.8 repository, which is recom- this: 64int mended for the X2 and U3: (with 41 registered patches, see # apt-get install nas libqt4- perl -V for more detail) # git clone --depth 1 https:// declarative-folderlistmodel Copyright 1987-2013, Larry Wall github.com/hardkernel/linux.git libqt4-declarative-gestures ... -b odroid-3.8.y odroid-3.8.y libqt4-declarative-particles Cloning into ‘odroid-3.8.y’... libqt4-declarative-shaders # python --version remote: Counting objects: 44530, Python 2.7.6 done. For desktop images, presuming the default window-system backend is based on X11/Xorg, you should install libxcb Kernel configuration options are available for experienced users to add and change drivers and its accompanying packages. This is also used for building QT4. It is installed using the command:

# sudo apt-get install “^libxcb.*” libx11-xcb-dev libglu1-me- sa-dev libxrender-dev

Enter Y to accept proposed option. QT4 support may not exist on Hardker- nel images by default.

Check the system

It is essential to make sure the system is ready for compilation. In this example case, the following commands/outputs are useful to verify that all of the tools are available and up to date:

ODROID MAGAZINE 18 LINUX KERNEL

remote: Compressing objects: 100% (42780/42780), done. remote: Total 44530 (delta 3428), reused 16016 (delta 1191) Receiving objects: 100% (44530/44530), 122.03 MiB | 161.00 KiB/s, done. Resolving deltas: 100% (3428/3428), done. Checking connectivity... done. Checking out files: 100% (42143/42143), done.

In this case, we will fetch a cloned copy of only the latest commit to the 3.8.y kernel, instead the entire repository. Please note that if you are using an ODROID-XU, clone the 3.4.y branch instead:

# git clone --depth 1 https:// github.com/hardkernel/linux.git -b odroid-3.4.y odroid-3.4.y Hardkernel maintains open-source kernel repositories that are downloadable for free.

Select a defconfig

Change to the source root directory ing command, ignoring any warnings: Novice users should review and go using the command: through the options list but not alter any root@u3-2:~/odroid-3.8.y# make selections. Experienced users may want odroidu_defconfig to adjust the selections in the kernel con- # cd odroid-3.8.y/ HOSTCC scripts/basic/fixdep figuration menu based on their in-depth This is where all build related activi- ... knowledge of the kernel. ties are launched from. Check the list of # supported defconfig files using the com- # configuration written to .config Baseline resource mand: # usage

Configure additional To understand the implications of # ls -lsa arch/arm/configs/ modules the build process on resource usage, it odroid*defconfig is useful to get a picture of the resource 100 -rw-r--r-- 1 root root 101207 In this example case, since QT4 sup- usage, before and during, the build pro- Jul 14 13:11 odroidu_defconfig port was added (xconfig is a QT4 UI), cess, as shown in the screenshot of the 96 -rw-r--r-- 1 root root 96792 the xconfig module needs to be built us- command top. Jul 14 13:11 odroidx2_defconfig ing the following command to launch an 96 -rw-r--r-- 1 root root 96797 editor for the selection of options: Build the kernel and Jul 14 13:11 odroidx_defconfig selected modules In our case, we will select the # make xconfig odroidu_defconfig version, which con- CHECK qt To compile the kernel as fast as pos- tains hardware configuration options MOC scripts/kconfig/qconf.moc sible, using all 4 processors available in specific to the U3. Now, perform the HOSTCXX scripts/kconfig/qconf.o the U3, type the following command in first build step by executing the follow- HOSTLD scripts/kconfig/qconf the Terminal window:

ODROID MAGAZINE 19 LINUX KERNEL

include/config/kernel.release` update-initramfs: Generating / boot/initrd.img-3.8.13.26

Convert the current initrd into a u- boot compatible version, which adds a 64byte u-boot header:

# mkimage -A arm -O linux -T ramdisk -C none -a 0 -e 0 -n uInitrd -d /boot/initrd.img-`cat include/ Resource usage before build starts config/kernel.release` /boot/uIni- trd-`cat include/config/kernel. release` # make -j5 zImage modules # make modules_install Image Name: uInitrd It is recommended to perform the Update initramfs Created: Mon Jul 14 14:17:02 build process on an ODROID that uses 2014 active fan cooling. You can experiment Prior to boot-up using the new ker- Image Type: ARM Linux RAMDisk with higher -j values only if you are able nel, the following steps need to be per- Image (uncompressed) to keep the temperature of the ODROID formed to create the initial RAM filesys- Data Size: 2196336 Bytes = below the thermal limits. For the above tem (initramfs). First, copy the current 2144.86 kB = 2.09 MB command, the build process may take config to /boot so update-initramfs can Load Address: 00000000 15 ~ 30 mins, depending on pre-existing run properly, using the command: Entry Point: 00000000 system activity. Pay attention to build- Save the current uInitrd using the time warnings, especially related to your # cp .config /boot/config-`cat in- command: changes, if any. clude/config/kernel.release` It is interesting the note the very high # ls -lsa /boot/conf* # cp /media/boot/uInitrd /boot/ cpu-core usage (~90%) during the build 100 -rwxrwxrwx 1 root root uInitrd-`uname -r` process, as seen in the above figure. As 101420 Jun 13 01:02 /boot/config- # ls -lsa /boot/u* expected, the fan was spinning non- 3.8.13.23 2144 -rwxrwxrwx 1 root root stop! 100 -rwxrwxrwx 1 root root 2195134 Jul 13 22:43 /boot/uIni- 101207 Jul 14 14:15 /boot/config- trd Install kernel and 3.8.13.26 modules 2144 -rwxrwxrwx 1 root root Recreate the initramfs using the com- 2195134 Jul 14 14:17 /boot/uIni- The freshly built kernel and mod- mand: trd-3.8.13.26 ules can be installed using the following Enable the new uInitrd using the commands: # update-initramfs -c -k `cat \ command:

# cp arch/arm/boot/zImage /media/ Resource usage (top with P option) during build process boot/zImage

ODROID MAGAZINE 20 LINUX KERNEL YOUTUBE PLAYER

# cp /boot/uInitrd-`cat include/ YOUTUBE PLAYER config/kernel.release` /media/ boot/uInitrd # ls -lsa /boot/u* ALTERNATIVE 2144 -rwxrwxrwx 1 root root 2195134 Jul 14 14:18 /boot/uIni- USE TAMPERMONKEY trd TO WATCH VIDEOS 2144 -rwxrwxrwx 1 root root 2195134 Jul 14 14:17 /boot/uIni- by Jeremy “Cartridge” Kenney trd-3.8.13.26 Reboot

If no errors have been encounterd, reboot the system using the following commands so that the new kernel may take effect: Is your Youtube defaulting to the GreaseMonkey is, it’s an extension that

# sync && reboot HTML5 player, and any Chrome injects scripts into the website you are Web-Store addon that you’ve tried using and other neat features using After the reboot has completed, you does not work for forcing Flash Play- scripts. can verify that the new kernel is installed er instead? Are you tired of not using You can go to Chrome’s Webstore using the uname command to compare the resolution you want on Youtube and grab the Extension from http://bit. the timestamp and kernel version from or the bland white look of Youtube’s ly/1iL5YRd. You can use scripts on any before and after the build: Skin? Knowing a trick or two about website that does not have a security Youtube can help you address these against scripts.

# uname -a issues, and even give you the option There’s endless possibilities for devel- Linux u3-2 3.8.13.26 #1 SMP PRE- for a full screen or windowed version opers and an easy interface for beginners EMPT Mon Jul 14 14:02:33 PDT 2014 of your video clip for faster multi- that allows for quick and easy manage- armv7l armv7l armv7l GNU/Linux tasking. ment of your scripts. Here’s a neat simple trick using If you are using an earlier build of For questions, please visit the Tampermonkey and a short script! Chromium for use on early Debian original forum post at http://bit. Tampermonkey is like Grease- Builds, install the Legacy Tamper- ly/1ucMAlN. monkey (Firefox) but for Chrome. monkey instead. This requires you to And for those who don’t know what Download the CRX from this website

Tampermonkey is available from the Chrome Web Store

ODROID MAGAZINE 21 TIPS AND TRICKS YOUTUBE PLAYER

INTERESTING at http://tampermonkey.net. To install, Click install, then open up your You- Right-click and Save As to the folder of tube and a window will prompt you to LINUX your choice, then open up Chromium show you where the new settings are. settings and click on the Extension tab. Click on the Player tab and enable COMMANDS Drag ‘n’ Drop the CRX file you have Flash Playback in Player Type. if you CUTE PROGRAMS downloaded from the link above onto have a fast connection, disable Dash the Extension Tab Page. Finally, test out Playback for faster loading and fix vari- FOR YOUR NEXT the new options by going to http://www. ous hiccups made by a weak wifi signal. COFFEE BREAK youtube.com and watching a video. You now have access to more options you can think of, and can customize You- by Rob Roy Youtube Center tube in any way you like, even changing ant to see some of the fun the player theme and color. side of Linux? Try these This script gives you access to op- The script can be disabled by clicking W commands: tions you may have never seen before on on the Tampermonkey button in the ex- Youtube. You get to make use of Auto tension bar beside the Address bar, then All aboard!

$ sudo apt-get install sl $ sl

Predict the future

$ sudo apt-get install \ fortune-mod $ fortune

Moo

$ sudo apt-get install cowsay $ cowsay ‘ODROIDS are cool!’ Changing the player settings in the Youtube Center

Cow fortune teller Resolution to adjust the video to the res- clicking Dashboard and unchecking the $ sudo apt-get install \ olution of your choice, set the width and extensions of your choice. cowsay \ height of the windowed player, enable Have fun enjoying YouTube! fortune-mod $ fortune | cowsay or disable use of Dash Playback (which is block buffering instead of loading the We got YouTube working, and now all he does is upload videos of his expert gaming full clip for safe use on 3G). skills. X11 cow divination You can also add a download button on each video you watch to select the $ sudo apt-get install \ xcowsay \ format of your choice, add a repeat but- fortune-mod ton if you like that song you’re playing, $ fortune | xcowsay and many more features. One of the more useful options is The X11 cow is always right! the HTML5 Alternative, Flash Play- back. Go to Youtube Center’s Github at http://bit.ly/MANHYG, scroll down to Download and click Dropbox. Your Tampermonkey should open up right away and prompt you if you want to install the script you have chosen. ODROID MAGAZINE 22 ODROID-U3+ ODROID-U3 VS ODROID-U3+ THE NEXT GENERATION IN THE ODROID-U SERIES by Justin Lee

The U3+ improves upon the popular U3 by adding another USB port via host mode

e’ve been shipping the using an external bulky USB hub. It’s a age current on the HDMI port. It puts ODROID-U3+ (Rev dual-use port that works both ways! the PMIC into an undefined state and W0.5) since the end it prevents the auto-power-on function. of June 2014, with 4 main im- New USB host We moved the reverse current protection provements over the original U3: power protector IC IC from HDMI connector side to CPU/ NCP380 PMIC side, which solved the problem- • Micro-USB port is able to work atic auto-power-on issue. Now we can in USB host mode. AP2411 was used in Rev 0.2 PCB as turn on the board automatically by simply inserting the DC power jack even • The USB host power protector a USB bus power protector. However, IC was changed from AP2411 to some users reported that it could be when the HDMI is connected. NCP380. damaged by an electrical shock on the USB port. HW SPI port • HDMI reverse-current blocking To solve this issue, we removed the IC AP2331 was placed on the chip and added a wire, which changed it The Serial Peripheral Interface (SPI) correct place. to more durable NCP380 that includes bus is a synchronous serial data link that many reliable features like Under volt- operates in full duplex mode. The SPI • HW SPI port was added. age lock-out, Built-in Soft start, Ther- bus is added on the new J5 (IO Port #2) mal Protection, Soft turn-off, Reverse 4-pin connector on the PCB. Note that voltage Protection, ESD Compliance to SPI ports support only master mode and USB host mode with IEC61000-4-2 (Level 4), 8.0 kV (Con- a 1.8V interface like the other IO ports Micro-USB port tact), and 15 kV (Air). on Exynos processor. You can use 4 pins as GPIO mode as well as SPI mode. Af- By adding a power control IC HDMI reverse- ter booting, the pins are in GPIO mode RT9715, the Micro-USB port can work current blocking IC by default. in the USB host mode as well as in USB device mode, which we call Dual-Role- Some monitors or TVs have leak- Pin map bottom side view Device (DRD). Just plug in an OTG- to-Host cable and you will have another USB host available for peripherals, so that you can enjoy 4 USB ports without

OTG-to-Host cable to allow use of the Micro-USB port as a 4th USB host port

ODROID MAGAZINE 23 ODROID-U3+

$ sudo modprobe spi-s3c64xx

Then, load the module to activate the generic SPI, and you will have a standard SPI node.

$ sudo modprobe spidev Pin Descriptions Chart of U3+ GPIO pin arrangements $ /dev/spidev1.0 The procedure for Serial Flash also This example script sets all pins to echo 1 > /sys/class/gpio/gpio23/ begins by loading the module to active output and toggle 5 times at 1Hz fre- the SPI host. quency. At the beginning of the appli- value; cation launch, it unloads the SPI driver echo “GPB[4],GPB[5],GPB[6],GPB[7] $ sudo modprobe spi-s3c64xx modules to make sure the GPIO mode, set output HIGH” sleep 1; and releases the GPIOs for the next us- Then, load the serial flash (misc) age at the end. echo 0 > /sys/class/gpio/gpio20/ driver, and you will have a Serial Flash value; node. modprobe spi-s3c64xx echo 0 > /sys/class/gpio/gpio21/ modprobe odroid-ioboard value; $ sudo modprobe odroid-ioboard dmesg | grep ioboard echo 0 > /sys/class/gpio/gpio22/ $ /dev/ioboard-spi-misc modprobe -r odroid-ioboard value; modprobe -r spi-s3c64xx echo 0 > /sys/class/gpio/gpio23/ Please note that spidev.ko and odroid- value; ioboard.ko can’t be loaded at the same count=0 echo “GPB[4],GPB[5],GPB[6],GPB[7] time. stop=5 set output LOW” SPI host interface driver: sleep 1; echo 20 > /sys/class/gpio/export http://bit.ly/1qz8gHs echo 21 > /sys/class/gpio/export if [ $count -eq $stop ]; then echo 22 > /sys/class/gpio/export SPI generic driver echo “GPIO TEST STOP” echo 23 > /sys/class/gpio/export http://bit.ly/1rILc5X echo 20 > /sys/class/gpio/unex- port echo out > /sys/class/gpio/ Serial SPI Flash add-on driver echo 21 > /sys/class/gpio/unex- example http://bit.ly/1sOpccA gpio20/direction port echo out > /sys/class/gpio/ echo 22 > /sys/class/gpio/unex- gpio21/direction port We tested a Serial SPI Flash memory echo out > /sys/class/gpio/ echo 23 > /sys/class/gpio/unex- SST25WF020A on the new IO Shield, gpio22/direction port and the maximum speed was 40Mhz of echo out > /sys/class/gpio/ exit 0 SPI clock. To learn more about the SPI- gpio23/direction fi DEV driver in detail, please visit http:// done bit.ly/WAgUYC. while : The ODROID-U3 Rev 0.5 has some do Let’s access the SPI mode. If the ver- great hardware improvements, so we count=$(($count+1)) sion of your kernel was downloaded be- called it the ODROID-U3+. You can fore July 17, 2014, you must first update find the latest U3 Rev 0.5 schematics echo 1 > /sys/class/gpio/gpio20/ the kernel first. here at http://bit.ly/1oUShMn. In ad- value; dition, the new U3 IO Shield Rev 0.3 echo 1 > /sys/class/gpio/gpio21/ SPI driver module has been improved to include a new SPI value; Flash memory which can be connected echo 1 > /sys/class/gpio/gpio22/ For generic SPI usage, first load the to an SPI bus (http://bit.ly/1nSPTFj). value; module to activate the SPI host.

ODROID MAGAZINE 24 WEB SERVER TIPS AND TRICKS

INTERESTING INSTALL A HOME LINUX WEB SERVER COMMANDS USING LIGHTTPD AND NGINX CUTE PROGRAMS FOR YOUR NEXT TO PUBLISH YOUR WEBSITES COFFEE BREAK by @hamiko and Venkat Bommakanti by Rob Roy

ant to see some more of the fun side of Linux? Try these commands: ne of the most common uses for or eMMC module containing the lat- W a Linux machine is to create a est U3 Lubuntu image available from Odd name Oweb server for the purposes of the Hardkernel website. hosting a website, which is an essential 3. A network where the device $ sudo apt-get install toilet component to any business strategy or has access to the Internet and the $ toilet -f mono12 -F metal \ personal project. Whether you want to ODROID forums. ODROID Magazine create a live production server or a per- 4. Optional SSH access to the U3 sonal one for your home intranet, this via utilities like PuTTY (MS Win- article describes the steps involved in dows 7+) or Terminal (Mac, linux to enabling two of the popular light-weight perform the steps from a remote host web servers: nginx & lighttpd (aka computer. lighty). Although Apache server is also a pop- Server Installation ular choice for Linux web hosting, it is The toilet command thankfully does covered extensively on the PHP website Although it is possible to install not do what you think it does! at http://bit.ly/1wXDju1 with specific both web servers on the U3 at the same time, the steps below assume that only instructions for the ODROID located at Enter the matrix http://bit.ly/1rIb9Te. one web server is being installed. For The instructions also include add- simultaneous use, any configurations ing support for a secure web server conflicts, such as the use of the default $ sudo apt-get install cmatrix (openSSL-based HTTPS) and scriptable web port 80 by both servers, should be $ cmatrix resolved first. web applications (PHP5-FPM). FPM, Chase the mouse which stands for FastCGI Process Man- ager, is an efficient alternative to the classic FastCGI implementation. If you $ sudo apt-get install oneko are concerned about security related is- $ oneko sues and configuration when hosting a Do you want to play website, it is recommended to research it a game? well and implement relevant procedures before enabling access to the Internet. Periodic OS updates are also recom- $ sudo apt-get install espeak mended. $ espeak \ ‘Do you want to play a game?’ Requirements Cozy warm fire 1. Any ODROID board, with an appropriate power adapter. $ sudo apt-get install libaa-bin 2. A bootable 8+ GB MicroSD card $ aafire

ODROID MAGAZINE 25 WEB SERVER

1 - Lighttpd and Nginx

Setup root rights, by running the command sudo -s

2 - Nginx 2 - Lighttpd Install nginx using the command: Install lighttpd using the command:

# sudo apt-get install nginx # sudo apt-get install lighttpd Launch nginx using the commands: Launch lighttpd using the commands:

# sudo service nginx stop # sudo service lighttpd stop # sudo service nginx start # sudo service lighttpd start

3 - Nginx and Lighttpd

Launch a web-browser such as firefox and point to the ip-address of the device, using the URL http://

4 - Nginx 4 - Lighttpd

Install self-generated ssl keys/certificates, using the Check if SSL has been enabled in the lighttpd applica- following (single-line) commands (use command help tion, using the command: to get details on specified options): # lighttpd -v # mkdir /etc/nginx/ssl lighttpd/1.4.33 (ssl) - a light and fast webserver # sudo openssl req -x509 -nodes -days 365 \ Build-Date: Jan 28 2014 17:19:37 -newkey rsa:2048 -keyout \ /etc/nginx/ssl/nginx.key \ Note that the output reflects that SSL is enabled. Now, -out /etc/nginx/ssl/nginx.crt install self-generated ssl keys/certificates, using the following (single-line) commands: Appropriate destination directories first need to be created, if not already present. # mkdir /etc/lighttpd/ssl # sudo openssl req -x509 -nodes -days 365 \ When prompted for certificate information, you can -newkey rsa:2048 -keyout \ enter information such as: /etc/lighttpd/ssl/lighttpd.key \ -out /etc/lighttpd/ssl/lighttpd.crt Country Name (2 letter code) [AU]:US State or Province Name [Some-State]:CA Appropriate destination directories need to be cre- Locality Name (eg, city):San Jose ated first, if not already present.

ODROID MAGAZINE 26 WEB SERVER

4 - Nginx 4 - Lighttpd

Organization Name:YourCompany Enter the certificate information as indicated for the Organizational Unit Name:Engineering nginx case. Similarly check installed certificate. Common Name:YourName Email Address:[email protected] In addition, generate the corresponding .pem file using the commands: Check generated certificate, using the command:

# cd /etc/lighttpd/ssl # openssl s_client -connect localhost:443 \ # cat lighttpd.key lighttpd.crt | sudo tee \ -reconnect lighttpd.pem

If the certificate information entered earlier is now This .pem file is later used in the lighttpd configuration emitted, then it can be assumed the certificate was file. generated properly. Add SSL configuration to the lighttpd configuration, -us Add SSL configuration to the nginx configuration, using ing the following steps: the following steps:

# cd /etc/lighttpd/ # cd /etc/nginx/sites-available # cp lighttpd.conf lighttpd.conf-orig # cp default default-orig # medit lighttpd.conf # medit default Add the following block: The server block should match this example:

$SERVER[“socket”] == “:443” { server { ssl.engine = “enable” listen 80 default_server; ssl.pemfile = “/etc/lighttpd/ssl/lighttpd.pem” listen [::]:80 default_server ipv6only=on; server.document-root = “/var/www” } # ssl support listen 443 ssl; Check if the configuration update is ok, using the (single-line) command:

root /usr/share/nginx/html; index index.html index.htm; # sudo lighttpd -t -f \ /etc/lighttpd/lighttpd.conf # Make site accessible from http://localhost/ Syntax OK server_name localhost; ssl_certificate /etc/nginx/ssl/nginx.crt; Relaunch lighttpd using the commands: ssl_certificate_key /etc/nginx/ssl/nginx.key; # sudo service lighttpd stop location / { # sudo service lighttpd start # First attempt to serve request as file, then # as directory, then fall back to a 404. Relaunch firefox and point to the ip-address of the de- try_files $uri $uri/ =404; vice, using the HTTPS URL https://. # Uncomment to enable naxsi on this location # include /etc/nginx/naxsi.rules On the first access, certain dialog boxes will be prompt- } ed seeking a response.

Relaunch nginx using the commands: Select the following options:

# sudo service nginx stop I understand the Risks # sudo service nginx start Add Exception

ODROID MAGAZINE 27 WEB SERVER

4 - Nginx 4 - Lighttpd

Relaunch Firefox and point to the ip-address of the The welcome screen should appear as shown in the device, using the HTTPS based URL https://. The circled exclamation icon indicates SSL has been On the first access, certain dialog boxes will be prompt- configured OK. Note that the exclamation indicates ed seeking a response. Select the following option that a self-generated certificate is in use. buttons:

I understand the Risks Add Exception Confirm Security Option

The welcome screen should appear as shown in the figure to the right.

The circled exclamation icon indicates SSL has been configured OK. Note that the exclamation indicates that a self-generated certificate is in use.

5 - Nginx and Lighttpd

Install PHP5-FPM and other modules using the command:

# apt-get install php5-cgi autoconf automake autotools-dev curl libapr1 libtool curl libcurl4-openssl- dev php-pear php-xml-parser php5 php5-cli php5-common php5-curl php5-dev php5-gd php5-sqlite php5-fpm php5- mysql

6 - Nginx 6 - Lighttpd

Configure nginx for php support, using the following Update lighttpd for php support, using the following configuration (socket-based) options: (socket-based) configuration options:

# cd /etc/lighttpd/conf- # cd /etc/nginx/sites-available/ available/ # medit default # cp 15-fastcgi-php.conf 15-fastcgi-php.conf-orig # medit 15-fastcgi-php.conf … index index.html index.htm index.php; Add the following (socket-based) configuration:

fastcgi.server += ( “.php” => location ~ .php$ { (( fastcgi_split_path_info ^(.+.php)(/.+)$; “socket” => “/var/run/php5-fpm.sock”, “broken-scriptfilename” => “enable” fastcgi_pass unix:/var/run/php5-fpm.sock; ))

) fastcgi_index index.php; include fastcgi_ params; Enable additional fastcgi configuration, using the com- } mands:

ODROID MAGAZINE 28 WEB SERVER

6 - Lightppd

# lighttpd-enable-mod fastcgi # lighttpd-enable-mod fastcgi-php

These commands create files/links:

# ls -lsa /etc/lighttpd/conf-enabled total 0 lrwxrwxrwx 1 root root 33 Jul 13 16:14 10-fastcgi. conf -> ../conf-available/10-fastcgi.conf lrwxrwxrwx 1 root root 37 Jul 13 16:15 15-fastcgi- php.conf -> Once you’ve reached this screen, make sure to congratulate yourself for becoming an expert level web server installer! ../conf-available/15-fastcgi-php.conf

7 - Nginx and Lighttpd Update the fpm configuration: Update the php configuration file:

# cd /etc/php5/fpm/pool.d/ # cd /etc/php5/fpm/ # cp www.conf www.conf-orig # medit php.ini # medit www.conf

Add the following (socket-based) configuration: Enable the following config line:

listen = /var/run/php5-fpm.sock cgi.fix_pathinfo=1

8 - Nginx 8 - Lighttpd Create a sample .php script file, using the commands: Create a sample .php script file, using the commands:

# grep -w ‘^[^#]*root’ \\ # cd /var/www /etc/nginx/sites-available/default root \\ # echo ‘’ > info.php /usr/share/nginx/www; # cd /usr/share/nginx/www Relaunch lighttpd using the commands: # echo ‘’ > info.php # service php5-fpm stop && \ Relaunch nginx using the commands: sudo service lighttpd stop # sudo service lighttpd start && \ # service php5-fpm stop && sudo service nginx stop service php5-fpm start # sudo service nginx start && service php5-fpm start Relaunch Firefox and navigate to the .php file using the Relaunch Firefox and navigate to the .php file using the URL http:///info.php URL http:///info.php Verify that the PHP Info page is displaying properly. Verify that the PHP Info page is displaying properly.

Additional Resources

Read more about nginx at http://wiki.nginx.org, and learn about Lighttpd at http://lighttpd.net.

ODROID MAGAZINE 29 ODROID-VU ODROID-VU AFFORDABLE 9” USB HDMI TOUCH SCREEN A PORTABLE MULTITOUCH SCREEN FOR ANDROID, LINUX AND WINDOWS by Justin Lee

ou’d think that, with the massive growth in tablet computing, it The Odroid VU - A 9 Inch 1280 x 800 Multi Touch Screen Display Yshould be an easy matter to: 1. Locate a small high-definition display 1920x1080, and you can buy a price tag to match! And most of (HD) LCD screen a full-size monitor at that resolution, them have no touch screen option. 2. Connect it to an HDMI/LCD but that’s not what we’re about. We’re So we decided to develop a 9-inch uni- driver board looking for something small and por- versal HDMI screen with 10-points ca- 3. Attach a capacitive multi touch table, which is where it gets a bit tricky. pacitive multi touch input for ODROID screen on the LCD users. The name of display is ODROID- 4. Hook that up to your ODROID or There are very few small, portable, VU, which is pronounced as “view”. We other HDMI device HDMI screens available on the mar- hope this product can be a “View point” Unfortunately, it’s not quite that ket. Most of the ones out there have for your computer. simple at all, or we’d all have done it al- 800x480 or 800x600 pixels. These ready! The ODROID computers can are largely aimed at professional pho- Specifications tographers and videographers, with A back view of the Odroid VU components Display: 9-inch 1280 x 800 pixels TFT LCD

The ODROID-VU is Touch screen: Capacitive multi- available from the touch 10 points input (USB HID) Hardkernel Store

at hardkernel.com Dimensions: 224 x 153 x 11 mm with the plastic frame.

Power: 5V/1A DC

Ports: Power, Micro-USB, Type-A HDMI, Audio jack (3.5mm stereo)

5 keys: Volume control, Brightness control, Power on/off

ODROID MAGAZINE 30 ODROID-VU

ODROID-VU board closeup detail What’s inside points at the same time. It also has the USB HID Multi-touch standard proto- The HDMI to LVDS converter IC col which is compatible with Linux and XBMC, Chromium and Terminal on Ubuntu MST7871KM has an HDMI receiver Windows. with U3 on the ODROID-VU and an LVDS transmitter with analog The USB VID:PID is 2808:81c9 audio output. The IC also has an inter- which is very important information nal frame buffer to scale up/down the when you modify the HID kernel driv- image to fit into the 1280x800 output. er. Volume up/down and Backlight brightness control are also managed by the IC Use Cases with On-Screen user interface. The single-chip capacitive touch You can connect the ODROID-VU panel controller FT5826QSL supports to ODROID boards as well as PC, TV mutual capacitive touch panel up to 10- and other embedded boards if they have HDMI output. Some ODROID boards can’t generate a proper HDMI master clock for 1280x800 native resolution of ODROID-VU. So 1280x720(720p) is scaled up to 1280x800 to fit the full screen. 1920x1080 input is also supported via scale-down function. You can purchase the ODROID- VU, which comes with a power supply ODROID-U3 running Android 4.4 with an and micro-USB cable, at the Hardker- ODROID-VU attached as the main screen nel store (http://bit.ly/UmZEod). Block diagrams of ODROID-VU assembly Laptop running Windows 8.1 with an Raspberry Pi and Debian with ODROID-VU ODROID-VU used as a side monitor

ODROID MAGAZINE 31 PEPPER FLASH PEPPERFLASH CHROME PLUGIN FOR LUBUNTU 14.04 AN EASY WAY TO WATCH ADOBE FLASH ON YOUR ODROID LINUX SYSTEM by @Miltos edited by Venkat Bommakanti

he Adobe Flash Player for the Chrome web browser in Ubuntu Twas discontinued by Adobe several years ago, with no alternative available for playing Flash videos in Linux 5. PepperFlash Ver. 12.0.0.77 for the Terminal window: until recently. Google recently released Lubuntu 14.04 an updated Flash-compatible player pl- 6. PCMan File Manager (pcman- $ sudo pcmanfm ugin called PepperFlash, which includes fm) for Lubuntu 14.04 an ARM Ubuntu version. This article Right-click the icon for the down- describes the steps needed to download Download loaded tarball, which should be visible this plugin from Google and add it to the PepperFlash in the right-most pane, and selecting Chrome web browser running Lubuntu the Extract Here menu option. 14.04 LTS on any ODROID board, in- Login to the ODROID using the The plugin will be extracted to the cluding the X, U and XU series. default username of “odroid”, and /home/odroid/Downloads/Pepper- download the precompiled packaged Flash directory, as shown in the second Requirements version of the ODROID compatible screenshot. PepperFlash by navigating to http://bit. It is easier for some users to use the 1. Any ODROID board, with an ly/1yYEDQf in the Chrome browser command-line terminal window almost appropriate power adapter. window, which will be saved to the / entirely for these next steps. However, 2. A bootable 8+ GB MicroSD home/odroid/Downloads directory. using pcmanfm simplifies the process card or eMMC module contain- Launch a terminal session and navi- for those who want to save some typing. ing the latest Lubuntu image gate to the downloads directory, then In pcmanfm, copy the PepperFlash available from the Hardkernel launch pcmanfm with root privileges directory and paste it into the /usr/lib website. by typing the following command in directory. 3. A network where the device has access to the Internet and the Contents of the directory after the PepperFlash tarball is extracted ODROID forums. 4. Optional SSH access to the ODROID via utilities like PuTTY (MS Windows 7+) or Terminal (Mac, linux to perform the steps from a remote host computer.

ODROID MAGAZINE 32 PEPPER FLASH ANDROID GAMING

Configure Pepper MUPEN64PLUS Flash plugin TURN YOUR ODROID After closing pcmanfm, launch the INTO A NINTENDO 64 medit (installed by default in Lubuntu) RETRO GAMING editor and open the default configuration file of PepperFlash by using the CONSOLE command: by Rob Roy

$ sudo medit \ /etc/chromium-browser/default Copy the PepperFlash directory Modify the CHROMIUM_FLAGS After pasting the copied directory configuration paramete as a single line: into the system library directory at /usr/ CHROMIUM_FLAGS=” --ppapi-flash- lib/, the directory /usr/lib/PepperFlash upen64Plus is a Nin- path=/usr/lib/PepperFlash/ \ will be created. tendo 64 emulator for If using the command line instead, libpepflashplayer.so --ppapi-flash- the Android platform, version=11.7.700.225” M copy the PepperFlash directory to the and it runs great on the ODROID! system library directory by typing the To install Mupen64plus, visit the following command: Save the configuration file and close Mupen64Plus Play Store page at http:// medit as well as Chrome. bit.ly/YzRD1H, connect your joysticks,

$ sudo cp PepperFlash /usr/lib/ and immerse yourself in the glory that Validate the was the Nintendo 64! installation Paste the PepperFlash directory From top to bottom: F-Zero-X, Mario Verify that the PepperFlash plugin has World 64, and Mario Tennis 64 been installed correctly by re-launching the Chrome web browser and navigating to the URL chrome://plugins. Se- lect the PepperFlash plugin and click on the Details option at the right side of the webpage. Check the details ensuring the plugin information matches what is listed in the screenshot. Finally, enable the Always allowed option by checking the checkbox and close all Chrome windows. To make sure that the plugin is installed properly, reboot the ODROID, then launch Chrome again. Navigate to any page with Flash content, such as the Adobe Flash Samples website at http:// adobe.ly/UmTzrV. For additional information or questions, please visit the original information sources at http://bit.ly/1lstuyP.

ODROID MAGAZINE 33 IO SHIELD IO SHIELD DEMYSTIFIED HOW TO CREATE AN INTERMEDIARY BETWEEN THE HARDWARE AND THE HUMAN By Bohdan Lechnowsky

was recently contracted to work on during the fourth step, I find it necessary a project that would require a U3 to to fine-tune the design produced during The U3 I/O Shield is a powerful tool in an Ipotentially control valves, actuators the third step. Of course, the fourth step ODROID wizard’s magic kit and other devices and read inputs. That also involves testing and refining of the was exciting, because I knew I’d have a design based on the results of testing. chance to work with the U3 IO Shield -- root@odroid:/sys/class/gpio# cd something that I’ve wanted to do since it Steps 1 and 2 gpio304 was released, but haven’t had a chance to root@odroid:/sys/class/gpio/ do because of my busy work schedule. When I first attempted to use the IO gpio304# echo out > direction My first step when working with any Shield on Ubuntu, I had trouble find- root@odroid:/sys/class/gpio/ new hardware is to see if I can get it to ing concise instructions for getting it to gpio304# echo 1 > value ;Turns on work using the supplied examples, and work using the method that is easiest for the pin my second step is usually to post ques- Rebol to interface with. That took me to root@odroid:/sys/class/gpio/ tions to forum.odroid.com about setup the forums where I was eventually able gpio304# echo 0 > value ;Turns issues I discover. This continues until I to piece together this set of basic instruc- off the pin succeed in getting it to work. The third tions: and fourth steps, however, are ones that Update the Ubuntu kernel by fol- This is what I needed to start devel- I particularly enjoy. lowing instructions in the forum post at oping my IO-Shield dialect, which I de- The challenge of the third step is http://bit.ly/1o3vMJx. cided to name gpio. to boil down the functionality of the new hardware to the most simple, Type the following into Terminal: Step 3 elegant, flexible and efficient form as possible while throwing out any pre- odroid@odroid:/sys/class/gpio$ After quite a bit of thought and de- conceived notions of how that hardware sudo su sign, here are some examples of what I is currently designed to be accessed or root@odroid:/sys/class/gpio# mod- wanted my dialect to be able to do: controlled. This doesn’t involve any probe gpio-pca953x coding, but rather is a process of design- root@odroid:/sys/class/gpio# gpio [ ing a dialect to act as an intermediary modprobe i2c-gpio-custom init out P17 ;initialize pin between the user and the hardware bus0=4,200,199 P17 as an output while achieving all the stated goals. root@odroid:/sys/class/gpio# echo on ;turn on P17 The fourth step is to convert that tca6416 0x20 > /sys/devices/plat- wait .1 ;wait .1 seconds dialect into code using Rebol’s power- form/i2c-gpio.4/i2c-4/new_device off ;turn off P17 ful parse feature. Amazingly, once the root@odroid:/sys/class/gpio# echo deinit P17 ;deinitialize pin hard part of the third step is done, the 304 > export ;304 is equivalent P17 fourth part is quite simple. Most often to P17 on the IO Shield ]

ODROID MAGAZINE 34 IO SHIELD

• Whenever gpio is called, de- of an easier way to write a dialect, the gpio [ termine whether the IO Shield open-source developers of Rebol would init in [P00 P01] ;Set subsystem had already been ini- love to hear about it. pins P00 and P01 as inputs tialized. If it hadn’t, initialize it. init out [P02 P03 P06];Set Testing pins P02, P03 and P06 as outputs • Convert the disparate timing init pwm 1 .1 P04 ;Set pin systems to a standardized time During testing on the U3, I found P04 as a pulse-width-modulated system (PWM uses microsec- that utilizing PWM sometimes leads output with a onds, wait uses seconds). Sec- to instability in the operating system. I ; period of 1 onds are more easily handled think this might have something to do second and a pulse of .1 seconds by most people, so decided to with the constant interrupts required to [P02 P06] on ;Turn standardize on seconds. make PWM work at high speeds in a pins P02 and P06 on software system. I also found that some- init .1 .01 P05 ;Set pin • Provide a level of abstraction be- times even at slow period/pulse speeds, P05 as a pwm output - the last tween the printed port numbers PWM was sometimes laggy and inaccu- initialization on the IO Shield with the /sys/ rate. ; (P04) was a class/gpio port numbers. Also found during testing was that pwm, so it was remembered for using Rebol’s write command would this init. • Allow handling standard I/O sometimes not work, but other times init gpio in P07 ;To and PWM within the same it would work fine. I haven’t yet been change back to standard I/O, dialect without any need for able to determine the circumstances that specify gpio. understanding the underlying lead to this undesirable behavior. Rebol wait .01 ;Wait .01 mechanism. also has an echo command that would seconds work sometimes even when write would P06 off ;Turn pin P06 • Reduce the required wordiness not. The most reliable (but by far the off of the dialect by allowing single slowest) method was to initiate a bash- P03 on ;Turn pin or multiple ports to be operated based echo command from within Re- P03 on on simultaneously, and unneces- bol. In my testing, this method was over read speed P00 ;Read the sary words to not be required, 25 times slower than the native write value of pin P00 into system/ but allowed when the user uses and echo commands in Rebol. gpio/val/speed them, and to remember the last read rpm P01 ;Read the pin initialization types and ports Results value of pin P01 into system/ so the following commands gpio/val/rpm don’t need to re-specify them You can download the dialect for wait 5 ;Wait 5 unnecessarily. your own use at http://respectech.com/ seconds odroid/gpio.r3, where you can leave deinit [P04 P05] ];Deini- • Testing had to be performed feedback. The gpio.r3 dialect definition tialize pins P04 & P05 (this is with different methods of read- script is editable, so feel free to make the way to turn off ing/writing to/from the /sys/ changes and improvements! ; a PWM pin) class/gpio and writing to the The I/O Shield is now yours to command! wait 1 ;wait 1 sys/class/soft_pwm directories second for reliability and performance reset ;Deinitial- under different conditions. ize all standard I/O and PWM pins ] Fortunately, incorporating this type of functionality within Rebol’s parse is Step 4 quite straightforward and easy once you become familiar with it. In order to get to this level of abstrac- Incidentally, parse uses a dialect to al- tion, the following hurdles had to be low you to easily define the rules for your overcome by the dialect: dialect! Because of this, if you can think

ODROID MAGAZINE 35 ODROID-SHOW DIGGING (INTO) THE ODROID-SHOW UNLOCK THE ARDUINO HARDWARE’S FULL POTENTIAL by Declan Malone

revious issues of ODROID Mag- azine covered the basics of setting Pup the ODROID-SHOW hardware and using it as a display for various data generated by your ODROID or PC. While this has many useful ap- The ODROID-SHOW can do much more than display simple text data plications, it only scratches the surface of what’s possible with the SHOW. At the SHOW example software can be information. heart of the device is an ATMega328p downloaded from Hardkernel’s official For this article, I’ll be concerned with chip, which is the same kind of mi- GitHub repository: looking at contents of the “show_main/” crocontroller that’s contained in many and “libraries/” directories, which are ex- models of the popular Arduino plat- $ mkdir ~/src; cd ~/src plained in the block diagram shown on form. This means that almost anything $ git clone https://github.com\ this page. that you could imagine using an Arduino hardkernel/ODROID-SHOW for could just as easily be made to run on $ cd ODROID-SHOW Parts explained the ODROID-SHOW. This series of articles aims to dig You will find directories named “ex- Terminals (meaning some kind of below the surface, so to speak, and to ample/”, where you will find programs keyboard and display combination) have introduce you to using the ODROID- to run on the ODROID or PC host, been around for over a century, even be- SHOW as a programming platform in its “show_main/”, where you will find the fore the first computers were built! As own right. In this installment, I’ll cover main program to run on the SHOW, computers became more commonplace, the software components that come pre- and “libraries/”, where the various Ar- many of the old terminal devices were installed on the ODROID-SHOW, how duino support libraries live. Depending put to use as dumb data entry and dis- they work, and how you can modify on when you downloaded the sources play devices. In the early days, instead them and upload your changes to the de- from github, you may see other direc- of personal PCs, it was much more com- vice. I’ll use a simple example of a Man- tories, too, such as one for the weather mon to have a large and powerful com- delbrot Set viewer to demonstrate this. module, which I won’t cover in these puter (such as a mainframe computer) In the second article, I’ll deal with articles. connected to lots of different terminals. some options for connecting the SHOW You may already have looked at Because of the wide variety of differ- to some simple electronic components the programs in the “example/” direc- ent kinds of terminal devices, as well as via the two GPIO headers. Finally, the tory. If not, now might be a good time the wide range of features that newer, third article will look at building a com- to have a look, so that you can familiar- more sophisticated terminals offered plete, self-contained game on the hard- ize yourself with some of the capabilities (such as coloured text, an audible bell, ware itself. of the ODROID-SHOW. You can also ability to position the cursor or clear the The latest version of the ODROID- check out the previous articles for more screen, etc.), some sort of standardisa-

ODROID MAGAZINE 36 ODROID-SHOW

tion was needed. The list of “ANSI es- Arduino the official software. Let’s get started by cape code” (such as “ESC[2J;” to clear Programming Basics installing the Arduino IDE. On Debian/ the screen) was the result. Ubuntu systems this is done by typing: While this might sound like quite an All the software components includ- archaic system (after all, we all have PCs, ed in the official software for the SHOW $ sudo apt-get install arduino laptops and tablets now, not terminals!), device are written in C++. If you know actually it’s still in common use today. If C++ (or even C) already, you should have This will install a lot of other pro- you use “xterm” or a more modern no problem starting out on program- grams besides the IDE, including a equivalent (like “gnome-terminal”) you ming for this platform. There are some cross-compiler (“avr-gcc”) and some sup- can still use the ANSI escape codes for minor some differences in the way C++ porting tools (“avrdude” being the main all the things that used to be done on is used on the Arduino, and you should one). For the most part, you don’t need dedicated terminals. be aware of them. For example: to worry about all these extra tools, since More importantly for our discussion the Arduino IDE will call them transpar- here, this is exactly what the “show_ • Instead of using low-level com- ently for you when it needs to. Later on, main” program block in the diagram mands like “gcc” and “make”, all if you want to change over to using these above is implementing by programming your editing, compilation and tools directly (with your favourite edi- the Arduino to behave as if it was a ter- uploading of programs is done tor and Makefiles), you’ll be able to do minal screen. in a graphical IDE (Integrated so. For these articles, however, I’ll stick You can check out the full list of Development Environment) with the simple IDE option. “escape codes” that the software im- named, appropriately, Arduino. plements by referring to http://bit. There are four other important setup ly/1nkYKUt. I’ll come back to this lat- • Programs written for the Ardu- steps: er when I add an ANSI-like escape for ino are often called “sketches”, drawing a single pixel on the screen. and generally have a “.ino” file 1. Tell the IDE where you will The other box on the left is for the se- extension store your “sketches” (not where rial connection to the PC (or ODROID) you downloaded the sources host. It’s used both for receiving data • Programs do not have a from github!) from the PC and also for printing de- “main()” function, since this is 2. Tell it which serial port to use to bug information, which can be very supplied by the Arduino com- communicate with ODROID- handy when writing Arduino/SHOW pile system SHOW (this may change if you programs. reboot or move USB devices On the right-hand side, we have • All initialisation is done in the around) two libraries that were also developed program’s “setup()” function 3. Tell it which version of the by Adafruit. The top one implements Arduino is being used high-level graphical primitives, such as • Arduino programs also require a 4. Tell it where to find your librar- printing a character, drawing points, “loop()” function. As the name ies lines and circles, and filling in rectangu- suggests, this function is called lar areas with solid colours. This can be in an infinite loop directly after All steps except Step 3 are covered seen as the platform-independent part of the “setup()” function returns in the official ODROID wiki page at the stack. http://bit.ly/1p8uitU, so I won’t repeat Below that, we have the platform- These are all relatively minor differ- them here. For Step 3, select “Tools > specific part of the graphics code. It ences to working on a “real” computer, Board > Arduino Uno”. The ODROID- knows about how the ATMega chip is so it’s actually quite easy to dive into de- SHOW is fully compatible with the pre- wired up to the TFT module, as well as veloping programs for the Arduino (and built Arduino Uno configuration. the protocols needed to communicate SHOW!) platform. If you are running an older version with the actual hardware, as shown in of the Arduino program (for example, the box below. Development my Debian Wheezy distribution only We won’t be delving too deeply into Environment provides version 1.0.1 of the program), how this side works, but you may be then in Step 4 there may not be an “Add interested in examining the code if that For our first step with programming Library ...” option under the “Sketch > interests you. the SHOW, we’ll just compile and reinstall Import Library” menu option. If your

ODROID MAGAZINE 37 ODROID-SHOW

Diagram of the Finite State Machine for the ANSI parser Adding a “plot” command version of Arduino is too old like mine, the green “right arrow” mark in the row then you will have to add the “GFX” and of icons directly underneath the menu When I first used the ODROID- “ILI9340” libraries manually by creating bar. SHOW (v1.1 of the software), it sup- symbolic links from the “libraries” direc- ported lots of ANSI escape characters for tory of your sketchbook directory (set If all goes well, you should get some drawing text on the screen, but it didn’t up in Step 1) to the individual library sort of indication in the message panel include any other graphics primitives. I directories as contained in the code that at the bottom, and the SHOW will then decided to change that by adding a new you downloaded from Github. For ex- reboot. After a successful flash and re- escape sequence to let it plot a single ample, if you downloaded into the “~/ boot, you’ll need to remove the jumper point on the screen. Here’s how I went src/ODROID-SHOW” directory, you before running any tests, such as those about adding that feature. can create the links with: in the “examples/” directory. Jumpers The first thing that I did was to see if tend to be small and fiddly, so try to re- there was an existing ANSI escape code $ cd ~/sketchbook member where you put it after removing for plotting points. As it turns out, there it! Alternatively, leave it attached to just isn’t, so I chose this as the syntax for the $ mkdir libraries; cd libraries one of the pins on the P2 header. You new command: $ for d in \ can also get different types of jumper

~/src/ODROID-SHOW/libraries/*; that have an extra tab on top. They tend ESC [ row ; col X do ln -s $d .; \ to be a lot easier to attach and remove and are a little bit harder to lose because By examining the code in “show_ $ done they’re bigger. You don’t need to have main.ino”, You can see that the “par- one of these, but I find that it helps. sechar()” function is called every time a After these setup steps, we can load If things didn’t go well, then you can new character is read from the PC over “show_main.ino” into the IDE. Af- check the message panel to give some the serial port. The parser uses what’s ter that, there’s only one more thing to idea of what went wrong. You’ll get dif- called a “Finite State Machine” (or do before reprogramming the device, ferent messages depending on whether “FSM”). This is quite commonly used and that’s to attach the programming the compilation failed (eg, due to miss- in any application where you have to jumper. This is used to short-circuit ing libraries or syntax errors) or there build up complex commands one char- a set of two pins labelled P2 on the was a problem with uploading (like if acter at a time. board. They’re located between the reset you forgot to reattach the jumper). It’s A FSM-based parser is simply a list of switch (marked ‘Reset’) and the power pretty user-friendly and you should be “states” (which track partially recognised LED (marked ‘Alive’). Once you’ve able to figure out what went wrong based commands) and “transitions” (which are done that, all you have to do is click on on these messages. followed by seeing a new character from

ODROID MAGAZINE 38 ODROID-SHOW

the input). Please refer to the diagram to the right, which shows some of the FSM for the ANSI parser. This is not a 100% accurate or complete depiction, but it should help to explain how the parser works in general. I have highlighted in green the path that would be taken for the parser to recogn- ise my new point-plotting command. As you can see, the code is simply “grafted” onto the existing graph structure. Once I knew where the new code would go, the code to implement the new command was very simple:

case ‘X’: ODROID-SHOW displaying a Mandelbrot set

row = (row > right_edge0) ? right_edge0 : row; software, so you can check for yourself Mandelbrot Set where the code was added. col = (tmpnum > bottom_edge0) ? If you can understand how the parser A common first step when checking bottom_edge0 : tmpnum; is organised, then it should be possible out any new graphics hardware is to dis- to add more features to it by following play the Mandlebrot Set on it. In the tft.drawPixel(row, col, the same method as above. You could, unlikely event that you’ve never heard foregroundColor); for example, add more escape sequences of this before, the Wikipedia page at for drawing circles, lines or boxes, all of http://bit.ly/1mQ75y3 is a good place break; which are available from the GFX li- to start. That page also includes pseudo- brary but not currently exposed to the code for generating the Set, so I won’t This does bounds-checking on the PC side. need to cover that here. supplied row and column values then It would be quite straightforward to You can download my code from a calls the appropriate method from the implement a set of LOGO-style primi- fork I made of the official Hardkernel GFX object (“tft.drawPixel()”) using the tives, for example, with commands for SHOW repository by typing the follow- current foreground colour. moving forward or backward, rotating ing commands: These changes were since incorpo- the “turtle”, putting the pen up or down, rated into a later version of the official and so on. $ cd ~/src

ODROID-SHOW displaying a Mandelbrot set $ git clone \ https://github.com/declanmalone/ ODROID-SHOW.git SHOW-fork

$ cd SHOW-fork

There are actually two versions of the code included here. The first, in the “examples/” directory is called “mandelbrot.c”, and it’s intended to be run on the host (PC) side. A “Makefile” is included to compile it automatically on an ODROID machine or another Li- nux system. There are a few things to note about this code:

ODROID MAGAZINE 39 ODROID-SHOW

1. It includes some code based on Native Generator data with two calls to “spi- the official “port_open.c” pro- write()”. gram. This code opens the USB I also wrote a version of the Mandel- serial port and sets the baud rate brot Set program as a sketch designed to It takes the ATMega chip just over and other important param- run independently on the ODROID- two minutes to render the full im- eters. This means that the code SHOW, without needing any host age with a maximum iteration value of does not need to have a separate PC. The sketch can be found in the 1000. Considering that the chip has “port_open” program running. “duino_fractal/” directory. Compiling no floating point capability and it only and installing is done in the same way as runs at 16MHz, this isn’t too bad. The 2. The “plot_point()” function you did for the official terminal emula- native code also has one advantage over sends the appropriate “ESC [ tor software, as described earlier. the PC code: since it doesn’t receive any x ; y X” string over the serial The native code is broadly similar to data over the serial connection, it doesn’t port. It also sends a separate the version for the PC, with some dif- need to delay after writing each pixel. “ESC 3 ? m” string to set the ferences: When I wrote the code, I had initially colour of the point. intended to use a potentiometer and two • It’s written in Arduino-style push buttons to allow the user to zoom 3. That function also includes C++, with a “setup()” and (an in and out on a particular screen area (in appropriate error-checking empty) “loop()” function a similar way to the video at http://bit. to make sure that the full ly/1yZ0UgB), but I never completed string was actually written to • It makes use of the GFX and that part. As a result, only some of the the device. If the send buffer ILI9340 libraries directly code to support this, such as definition overflows, then “write()” will of hardware pins and ability to paint in- fail and set the error value to • It sends back debug messages dividual “panels”, for easier scrolling, are “EAGAIN”. over the serial connection with actually implemented. The code correctly handles this “Serial.print()” calls case by advancing the write Summary buffer and trying the “write()” • It also uses the Arduino’s inter- again until the full string has nal timer function “getmillis()” We’ve had a lot of ground to cover been sent. to time how long it takes to in this article. I hope that it has served render the screen as a good introduction to the basics of 4. There is a call to “usleep()” af- programming the ODROID-SHOW ter every write. This is needed • It writes to the TFT screen’s and has helped to explain some of the because the ATMega is only a memory directly rather than things that the platform is capable of. I single-threaded computer and calling “drawPixel()”. This think you’ll agree that it’s actually not if the PC side sends data too means that it calls “setAddrWin- that difficult to get started with writing quickly, it is possible that some dow()” once for each “panel”, code for it. In the next article, I’ll get of the data will be lost. Adding then write each pixel’s colour to grips with hooking up the SHOW to a short, user-adjustable delay other components via the GPIO pins. after every write is a simple way of working around this.

Although I wrote this version of the program to use the “X” escape code, it would also be possible to send the data across by first sending an “ESC [ x1 ; y1 , x2 ; y2 i” escape sequence and then sending the colour data for each pixel as if you were sending an image. Please refer to the “images.sh” example program from the official sources to see how that can be accomplished.

ODROID MAGAZINE 40 OS SPOTLIGHT OS SPOTLIGHT:

POCKET ROCKET AND Pocket Rocket and Couch Potato for the U, X and XU series may COUCH POTATO be downloaded from ANDROID 4.X PREBUILT IMAGES http://bit.ly/1zYsZFt. FOR THE ULTIMATE SET-TOP BOX NOW AVAILABLE IN KITKAT by Rob Roy, Editor-In-Chief

he ODROID family of computers was originally marketed as an TOpen Android system, offering application programmers an alternative to purchasing an expensive Android phone and rooting it. ODROIDs runs Android extremely well, while including many useful features such as hardware video decoding and joystick drivers, which would need to be installed sepa- rately on a comparable Linux X11-based system. When I began using ODROIDs, I set up a set-top box using an Ubuntu desktop environment called LXDE, which let me stream and download media files, then play them using Xine or The list of pre-installed apps for Pocket Rocket and Couch Potato XBMC. It could render 720p videos well, but only some 1080p videos, with U, and XU) is flawless when using MX Before purchasing my first lots of dropped frames, and was watch- Player, and plays videos of any resolution ODROID, I had never before consid- able but choppy. After trying several and encoding. ered using Android as my main operat- tweaks to achieve smooth video, includ- At the time, I had also purchased an ing system, but after putting together ing overclocking and setting kernel op- Apple TV, which has a friendly interface, the Pocket Rocket image, I learned the tions, I reformatted my SD card and in- but I couldn’t install new applications, advantages of it. Android is an extremely stalled Android Jelly Bean 4.1.2 on my since the iTunes store isn’t available for stable OS, and even when an app crashes U2 instead. the Apple TV. However, an ODROID or starts to slow down, Android makes The Jelly Bean 1080p video experi- Android system allows unrestricted init easy to shutdown the application. It ence was incredible, and exactly what stallation and removal of applications also has a shallow learning curve, with I was looking for! Using both XBMC just like an Android phone, with thou- large, friendly icons, as well as shortcut and MX player, the ODROID could sands of applications and games available buttons that are intentionally similar to smoothly play even the densest videos from the Google Play Store. Android is other operating systems. on the XBMC website (such as Big Buck already rooted, so the operating system In order to use Android efficiently, Bunny) that are known to bring other can be customized, self-writte apps can I use the built-in keyboard shortcuts, systems to a stuttering halt. The video be installed, and administrative func- which are similar to other desktops such decoding on every Android build (X, tions can be performed as the root user. as Windows, Ubuntu and OSX.

ODROID MAGAZINE 41 OS SPOTLIGHT

Keyboard Shortcuts

Ctrl-C Copy Ctrl-V Paste Ctrl-A Select all Ctrl-W Close Window Ctrl-Right Arrow Move right one word Ctrl-Left Arrow Move left one word XBMC is the go-to program for all of your media center needs. It supports Ctrl-Shift-Right Arrow video, music, addons, and even can launch other applications. Select word to the right Ctrl-Shift-Left Arrow basically any task that a desktop PC can stead by depressing the left mouse but- Select word to the left Alt-Tab perform, but in a different way. ton for several seconds. For example, Switch program As an example, most desktop PCs of- in ES File Explorer, to select multiple Alt-Esc fer a word processor, and save its files folders, long click the first folder, which Desktop to the local hard drive. In Android, the will then bring up a checkbox interface, Control-L software used for editing documents is where other folders can be selected with Go to address bar called Google Drive, which stores the a single click. information on the cloud. With Google Android Experience Drive, you can pick up any mobile device, laptop, tablet, or desktop PC, log eMMC vs SD card into Google Drive, and have access to all Android is especially suitable for be- of your documents without needing to Android is designed to run from an ginners, or anyone that has experience carry a USB thumb drive with you. eMMC module, and a distinct advan- with a mobile phone interface. How- One notable difference with Android tage of ODROID computers is that this ever, even as an expert computer user, is that the right mouse button is actu- module can be removed and replaced sometimes I just want to change some- ally used as the “Back” button. To bring easily. Although an SD card will tech- thing without having to adjust settings, up menus that would normally be done nically run Android, the slow speed of navigate menus or move windows. An- with a right click, use a “long click” in- the SD card hinders the experience be- droid is perfect for this, and can perform cause of the disk I/O. I stopped releas- ing Pocket Rocket images on SD card XBMC Gotham 13 starting up for the first time. This is the final release of because of the amount of time spent XBMC, since they are changing the name to Kodi for version 14. clicking the Android “not responding” popups while customizing the image. However, I discovered that the Ice Cream Sandwich (ICS) version of An- droid runs smoother than Jelly Bean, when comparing them both using an SD card. As a result, I created a special SD card version of Pocket Rocket called Couch Potato that has all of the same applications as Pocket Rocket, but uses ICS for better disk performance. If you don’t have the eMMC module, then you can install Couch Po- tato instead, and enjoy all of the same features as Pocket Rocket. Occasion-

ODROID MAGAZINE 42 OS SPOTLIGHT

MX Player is the best media player available for Android on the ODROID, and offers smooth hardware video decoding in 1080p. ally, Couch Potato will interrupt with a “not responding” popup, such as when Firefox and Chromium being the most XBMC and MX Player offer top-notch downloading multiple applications from popular. Chromium has several fea- 1080p viewing experiences, with ad- the Play Store, but they are less frequent tures that aren’t available in Firefox, vanced features such as multi-language than when running Jelly Bean from SD such as touchpad swiping and key- subtitles, audio visualizations, net- card. Both images offer the exact same board shortcuts. Either browser can be work streaming and Samba file shar- applications, and only differ in the ver- synchronized with other devices to au- ing. XBMC also supports add-ons that sion of Android 4.0 vs. 4.1. tomatically download any bookmarks offer TV channels and other media ser- Google Play Store that were made on the same Google ac- vices. count. Youtube videos should be played MX Player is arguably the best audio using the native Youtube app in order to and video player available for Android, The Google Play Store is accessed by leverage the video decoding hardware. and is able to play nearly any kind of pressing the Apps icon made of 6 small media file. It also has a full screen op- squares on the upper right of the An- Gmail and tion that hides the Android buttons at droid desktop, then pressing the Shop Google Drive the bottom of the screen automatically, button on the upper right corner of the which remain visible while watching Apps menu. After logging into the Play More than one Google account may videos in XBMC. Make sure to turn on Store using a Google or Gmail account, be added in the Settings app, and both all of the HW+ decoding options in the an enormous library of applications and Gmail and Google Drive offer an ac- Settings menu. games becomes available, with many count dropdown as a way to easily switch of them offering free versions. This is between multiple accounts. Google tTorrent also how applications are updated, and Drive includes word processing, spread- notifications will periodically appear re- sheet, presentation, forms, and draw- Torrents are automatically associated questing permission to update them. ing applications which are intended as by Chromium with the tTorrent app, If you already have an Android a lightweight alternative to Microsoft which is a peer-to-peer network down- phone, you can quickly install your fa- Office. The advantage of using these loader suitable for large media files. vorite applications by selecting the “My cloud-based applications is that if there is Completed files are, by default, saved to Apps” section from the upper left of the an issue with the storage device, and the the /mnt/sdcard/Downloads directory, Play Store, then pressing the “All” tab operating system needs to be restored, with the option to choose an alternate which keeps track of any applications no documents will be lost, since they are location. Keep in mind that tTorrent is that you’ve used on any other Android stored on the cloud rather than a local extremely resource-intensive, and high device. hard drive, as previously mentioned. disk activity may slow down the An- droid interface. It’s usually best to move Chromium and XBMC and Firefox any torrents or download activities to a MX Player second ODROID running Linux services, and access the completed files us- There are only a few browsers avail- What set-top box would be complete ing the Samba sharing built into ES File able for the Android platform, with without a killer media player? Both Explorer.

ODROID MAGAZINE 43 OS SPOTLIGHT

the ODROID! The developers adapted the game for use with a keyboard and mouse. Holding down the left mouse button is the identical to dragging on a touchscreen. Free versions of Star Wars, Star Wars II, and Space are already installed, and other versions, including more recent releases, can be downloaded from the Google Play Store.

Mupen64 Plus and Retroarch

Pocket Rocket can turn an ODROID Netflix is an essential part of any set-top box! into a family gaming super-console with these emulator apps. Both Mupen64 Plus and Retroarch support up to 4 si- Netflix videos at full screen resolution without multaneous controllers, and support playback glitches. The TED Talks app tens of thousands of console games. The Netflix is what every entertainment provides hours of educational and in- Google Play Store includes many free system needs, and the ODROID can spirational videos on a huge variety of emulators, and I tested a few of them for run it in full 1080p on your giant living topics, presented by a non-profit organi- both game and controller compatibility room screen. This subscription-based zation. For more information on TED before deciding to include Mupen64 service not only offers a massive catalog Talks, visit http://www.ted.com. Plus and Retroarch. of movies, there are many original shows Retroarch is a multi-system emula- that can only be seen on Netflix. The Hangouts tor, and comes with many console cores Netflix Android app is easy to use, with a that range from Atari 2600 to SNES similar interface to the desktop version, The ODROID, when paired with to Sega Genesis to PlayStation Portable and movies can be searched using an ac- an external camera such as the Logitech and PlayStation 1. It’s an open-source tual keyboard instead of picking letters C920, supports 1080p video in Hang- app that combines many generations of with a tiny remote from an alphabetic outs, just like a desktop PC. Either the retro and modern console video gaming list like a 1980s arcade game. internal camera microphone or an exter- consoles into a single system, and allows nal microphone headset may be used. continuous hopping from console to Youtube and TED console without having to reconfigure Talks Angry Birds the controllers. Please refer to the July issue of ODROID Magazine for instruc- The Youtube app runs extraordinari- One of the most popular mobile tions on connecting Xbox 360 wireless ly well, and can play 1080p streaming games of all time is even more fun on controllers to Retroarch, which I have

Who doesn’t like Angry Birds? Pocket Rocket and Couch Potato come with 3 versions of this highly addictive game.

ODROID MAGAZINE 44 OS SPOTLIGHT found to be the most compatible controllers for use with Android. Mupen64 Plus is an excellent Nin- tendo 64 emulator, and was the least buggy of all those that I tried. It has a great interface for setting up controllers quickly, and comes with several pre-built controller profiles, including Xbox 360 wireless. Both Retroarch and Mupen64 Plus allow use of the keyboard as a controller, as well as an alternative touchscreen controller interface, which is ideal for use with an ODROID-VU external touchscreen. ES File Explorer can be used to connect Samba drives for network media streaming. Pandora and PC Radio automatically mounts them. mouse, which can be shared between many computers. JuiceSSH provides Pandora is a subscription-based bVNCFree and the same functions as the Linux version app that chooses music for you based JuiceSSH of SSH, with a nice graphical interface on your past preferences and personal to organize the recently used list. taste. If you want to have a continuous I use Android as my main operat- non-stop music mix for a party or din- ing system primarily because of bVNC- Terminal Emulator ner, put on a Pandora station and press Free. With this excellent VNC appli- and BusyBox Free the power button on the top of the U3 cation, I can login to any of my Linux (or keyboard power button) to turn off computers and use the remote Ubuntu Terminal Emulator is an Android the screen. PC Radio is an Internet Ra- desktop as if it were a native Android version of BASH terminal, and can be dio app that includes broadcasts from all app. By setting up a VNC server on the used in conjunction with BusyBox Free over the world. second ODROID using Vino, I need to perform all of the Linux administra- only a single monitor, keyboard and tive tasks that are not included with ES File Explorer and Android, such as mount, grep, ping Ultra Explorer bVNCFree can connect to any Windows, and uname. For more information on Linux, Android or OSX machine. the BusyBox commands, please refer to These file explorers are more full- the official Wikipedia page at http://bit. featured than some desktop explorers, ly/1zwVNEP. offering Samba sharing, built-in zip ex- traction, application file associations, Jota+ and multiple copy/paste blocks. Ultra Explorer is available as an open-source Jota+ is a standard text editor, with project where developers are encouraged nearly all of the formatting and editing to contribute their own modifications at features that would normally be includ- http://bit.ly/1AzAeVG. ed in a desktop text editor such as Text- I used ES File Explorer’s LAN tab to Pad. Jota+ can be also used for web de- connect with my media server, so that velopment by using the ES File Explorer when I click on media files, they au- to associate .html and .php files with tomatically launch in MX Player, and Jota+. I created a Samba share on my MX Player streams them over the net- ODROID web server to allow remote work. Additional local hard drives may editing of the website files, and often use be hot-plugged into the USB ports and Jota+ to make quick changes to files via accessed using ES File Explorer’s Local the Samba share without the overhead of tab, which lists each USB drive after it starting up a full IDE.

ODROID MAGAZINE 45 OS SPOTLIGHT

Screen Orientation with third-party features, it can also serve and full!screen as a general-purpose Android test environment for your own applications, by These two applications enable total using the Android Debug Bridge (ADB) control of the Android desktop. Screen software. Install the ADB client on any Orientation will lock the screen in either host Linux machine by selecting it from Landscape or Portrait mode, depending the Synaptic Package Manager, plug the on the orientation of the monitor. The ODROID’s micro-USB port to the host The Pocket Rocket desktop with a swirl- full!screen application temporarily hides machine with a USB cable, and open an ing Milky Way galaxy animation the bottom Android menu until one of ADB connection by typing the follow- the bottom corner hotspots is clicked. ing in Terminal on the host machine:

Bluez IME Settings $ su and Joysticks # adb remount # adb shell Bluetooth controllers, such as the Wiimote, can be configured as input de- This will open an SSH-like session on vices using Bluez IME Settings, so that the Android machine, permitting access they can be used to mimic keyboard to the command line on the remote ma- The Games menu is where I spend most presses. Xbox 360 controllers will im- chine. Files can be transferred via ADB of my time mediately connect upon being plugged to Pocket Rocket using the command: in to Pocket Rocket, and can be used to navigate the desktop menu, launch ap- # adb push \ plications, and type using the on-screen keyboard. For more information on using ADB ODROID Updater and other ways of connecting to the and ODROID Utility ODROID from a host machine, please Chill out with Pandora or the worldwide refer to http://bit.ly/1xC42wk. Internet Radio using PCRadio The official Hardkernel version of KitKat Pocket Rocket is still in Beta as of August 2014, but the ODROID Updater can be used to import the latest improvements and bug fixes from Hardkernel as KitKat moves toward its final release. Follow the sequence of on-screen buttons to automatically install the system updates, which typically require a reboot. The ODROID Util- Chrome and Firefox are the most popular The System menu lets you access pro- ity program is designed to adjust boot browsers available teted files and other network computers variables such as 720p and 1080p screen resolution, initial screen orientation, and CPU governor settings. Additional boot options, such as whether to blink the alive led, can be tweaked by editing the file /mnt/sdcard/boot.ini.

Installing Custom Applications The Video menu also contains Google ES File Explorer and Ultra Explorer are Although Pocket Rocket is loaded Hangouts and TED Talks two full-featured Android file explorers

ODROID MAGAZINE 46 MEET AN ODROIDIAN MEET

AN ODROIDIAN Bo Lechnowsky, one of the Editors of BO LECHNOWSKY: the ODROID Magazine, playing his woodwind instrument EXPERT MAKER AND outdoors INSPIRATIONAL INVENTOR by Bohdan Lechnowsky edited by Rob Roy

Please tell us a little about yourself. vage what I could. I spent some time in I was born in Omaha, Nebraska USA to the public library Ukrainian and German immigrant par- reading books on ents. I moved to Ukiah, California USA electronic circuits to after I had been married for 7 years and learn more about it. had one son and a daughter on the way. I When I was 12, my now have two additional daughters for a school purchased a few total of 4 children, and have been married Apple II computers. I had for 23 years. In 1994, I started an Amiga to stay after school to use them My favorite Computer store. In 2001, I started a tech- which meant that I missed the bus ODROID is nology consultancy and we now employ and had a 2.5 mile walk home. Again, the U3 as it is a very about a dozen people, mostly technicians. I had to teach myself programming from powerful and capable computer with a library books, and a fair amount that I low price point, and there are a lot of How did you get started with computers? taught myself. I got my own Commo- U3-sized accessories like the Show, I/O dore 64 at age 15. In school and in the Board and UPS Board, all of which I Prior to computers, I had an interest in university, I worked on all types of com- have been working with a lot lately. electronics. I received my first solder- puters, mostly programming. ing iron at age 7. My parents lived very You’re an expert in the Rebol language, frugally, so I couldn’t afford to buy new What would you consider to be your and often write articles that showcase the electronic components. Therefore, I had favorite ODROID? to take apart discarded electronics to sal- simplicity of the language. What software have you produced with Rebol?

My entire company runs on Rebol soft- This is where all of the mad computer science experiments happen!

ODROID MAGAZINE 47 MEET AN ODROIDIAN ware I developed starting in 2003. Ev- erything from inventory and time log- Currently, I have been contracted to ging to invoicing, accounts payable and provide a solution to help improve food receivable, and graphical real-time track- production by real-time processing and ing of our progress toward our goals. In automation. In this project, we are using addition, I’ve developed super-efficient a U3 with Show and IO Shield boards surveillance cameras that capture and coupled with sensors including GPS and process video on-camera at 1920x1080 lasers, and Rebol handles all the logic. resolution @ 30fps, and I’ve written Another project I just completed was the monitoring software that can be setting up a video surveillance server us- used to keep an eye on what’s going on, ing a U3 and an external storage device. and review what’s already happened. I’m currently trying to find the time to For another project, I converted a cli- upgrade my 1978 Ford F150 4x4 pick- ent’s medical recruiting database from a up truck to have an ODROID-powered PICK mainframe to a Rebol/SQL solu- brain allowing me to do things such tion that has now been in constant use as replacing the entire dashboard with since 2001. I could go on, but I’d seri- digital touchscreens and Show boards, ously have to write a book to list all my starting and stopping the engine with projects written in Rebol. my smartphone, recording and checking fuel levels and performance data, What hobbies and interests do you have integrating GPS navigation, and many apart from computers? automation features. Unfortunately, my contract projects have to take prior- I like to say that if you need a hobby, ity over my personal ones, like upgrad- Hiking Smith Rock State Park in I’d be happy to give you one of mine. It ing my truck. If I have a chance to get Oregon with the family would be easier to list the hobbies I don’t around to it, I’ll be writing an article have. Some of the hobbies that I’ve been on my truck project for a future issue. ODROID with PoE (Power over Eth- spending more time on lately have been ernet). Of course, lots of USB ports are raising a family, playing keyboards with What type of hardware innovations would always a big plus (I know some boards my church’s band, developing new tech- you like to see for future Hardkernel already have quite a few). Maybe built-in nology products and business, working boards? bluetooth? With this said, my opinion is on the mechanics and body of my truck, that Hardkernel does a great job of bal- traditional blacksmithing, participating I haven’t looked into the technical re- ancing power and features with price. in outdoor activities (mountain biking, quirements of any of these, but as long camping, barbeque cooking, World Hu- as I’m allowed to make a wishlist I would What advice do you have for someone man-Powered Speed Championships), love to see a future Hardkernel board wanting to get started with ODROID traveling (including three mission trips with the newest Samsung SoC (looks programming? to Ukraine for a total of almost half a like I’ll get my wish with the XU3). It One of the big hurdles I think many year), linguistics, and editing. would also be amazing to have even a single laptop-style memory socket for Bo’s computer science laboratory is so Are you involved with any projects? expansion purposes, and running the big, it needed a second page to show everything!

ODROID MAGAZINE 48 MEET AN ODROIDIAN

Part of my business, Respectech, with the floating expanded metal people face is setting up a development floor and LED lighting underneath. environment. With this in mind, you can’t beat C programming as gcc (a C compiler) is already in almost every dis- favorite, of course, is Rebol. It runs on your project. For me, Rebol has the flex- tro, and nearly every platform uses C nearly every platform without any code ibility and capabilities to handle almost (including embedded devices like Ardu- changes, it is a single file download of every project I throw at it, and allows ino). One would think that bash would less than 1MB, and simple things are me to develop solutions in a fraction of also be a good option as it is also in- simple to do, while complex things are the time it would take with other lan- cluded in nearly every distro. However, still possible. Not only that, but efficient guages. And now that Red is maturing, my opinion is that bash goes overboard dialects are easy to develop to allow for it is going to be a great alternative option syntactically and is usually cumbersome building complex systems easily, which that will have nearly no learning curve with which to develop solutions. My reduces future development and debug- for developers familiar with Rebol. ging efforts. The You can visit Bo’s website at http:// Some of the “heavy lifting” we’re doing to get my 1978 Ford language you use www.respectech.com. F150 4x4 ready to have ODROIDs installed and controlling the should be based electronics. My father-in-law helped with this step. on the end goals of I can't tell you exactly what this project does (it's still top secret), but I can tell you that it involves a U3, a SHOW and an I/O Shield, among other things.

ODROID MAGAZINE 49