tutorials News - Page 37 of 45 - CNX Software

January 26, 2013March 28, 2013 by Jean-Luc Aufranc (CNXSoft) - 9 Comments

Raspberry Pi Now Has Experimental Support for VP6, VP8, MJPEG and Ogg Theora Video Codecs

The guys working on the Raspberry Pi (mainly dom) have added preliminary support for VP6, VP8, MJPEG, and Ogg Theora free video codecs, as well as Ogg Vorbis audio codec. Unlike H.264, MPEG-2 and VC1, those are not handled by the hardware video decoder in Broadcom BCM2835 processor, but are accelerated by the Videocore GPU. This means that only SD (and possibly 720p) videos are supported for those codecs. The best way to get support is probably to patiently wait for the Raspberry Pi foundation to release a new Raspbian image, but in case you couldn’t possibly wait, here are the steps to follow: Download and run Hexxeh’s rpi-update script in the Raspberry Pi in order to get the very latest build:

wget https://github.com/Hexxeh/rpi-update/raw/master/rpi-update
chmod 755 rpi-update
sudo ./rpi-update

wget https://github.com/Hexxeh/rpi-update/raw/master/rpi-update

chmod 755 rpi-update

sudo ./rpi-update

Add the following two lines to /boot/config.txt:

start_file=start_x.elf
fixup_file=fixup_x.elf

1 2	start_file=start_x.elf fixup_file=fixup_x.elf

Reboot the Raspberry Pi The GPU firmware is now updated, but you still need the latest version of omxplayer. […]

January 23, 2013January 23, 2013 by Jean-Luc Aufranc (CNXSoft) - 24 Comments

How to Access the Serial Console in HI802 / GK802 mini PC

One of the advantage of HiAPad Hi802 (aka Zealz GK802) is that it provides access to UART and I2C pins via through holes on the board. UART4 Tx and Rx pins give you access to the serial console which is a must for bootloader (U-boot), and kernel development or for debugging. The first thing is the open the casing and locate the debug pins on the board. The very best way is probably to solder a pin header, but since I don’t have header, nor soldering iron, I’ve done it the “MacGyver” way with 3 wires connected to TxD, RxD and GND, and some sticky tape. You can now insert the other side of the wires into your USB to TLL debug board (GND <-> GND, Tx <-> Rx, and Rx <-> Tx), and connect it to your Windows or Linux PC. The serial board should be recognized as a […]

January 16, 2013 by Jean-Luc Aufranc (CNXSoft) - No Comments

BoFs: Developer Tools and Methods: Tips & Tricks – ELCE 2012

Tim Bird, senior staff software engineer at Sony Network Entertainment, hosts a BoF session about tools & methods for embedded Linux developers at ELCE 2012. Abstract: In this Birds-of-a-Feather-session, Tim will share some of his favorite tips for developing embedded Linux software. This will include tips for using ‘git’, how he does multi-platform development, and tips for other tools that other developers might find useful. Prior to the event, Tim will do a survey and solicit ideas from other developers as well. Please come to this BoF prepared to share your own productivity tips for embedded Linux development. Tim talks is divided into the following key points: Git tips – How to finds info about commits (git log, git show), use aliases (e.g. for colored output), find a commit that caused problem (git bisect), and more Patch management – quilt patch managing tool, diffinfo, and splitpatch (to break patches apart) […]

January 16, 2013January 16, 2013 by Jean-Luc Aufranc (CNXSoft) - No Comments

Upgrading Embedded Linux Without Bricking – ELCE 2012

Arnout Vandecappelle, senior embedded software architect at Essensium/Mind, talks about ways to greatly decrease the risk of bricking your board/device during upgrade thanks to gubies scripts and tools at the Embedded Linux Conference in Barcelona, Spain, on November 6, 2012. Abtract: Embedded systems are often modified remotely, e.g. to upgrade the firmware or change the configuration. This may however break the system and render it inaccessible, which is a major problem if the device is hard to reach physically. Unfortunately, no catch-all failsafe solution exists to make sure that the device stays accessible remotely even if a modification goes wrong. Instead, the possible failures have to be anticipated and covered. This talk discusses some of the frequently occurring failures, how they can be detected and handled. These include power failure, kernel crashes, network failure and data corruption. We include examples of concrete use cases. Finally, there is room for discussion about […]

January 16, 2013November 23, 2014 by Jean-Luc Aufranc (CNXSoft) - No Comments

Understanding PREEMPT_RT (The Real-Time Patch) – ELCE 2012

Steven Rostedt, working at Red Hat, talks about Real-Time Linux at the Embedded Linux Conference Europe, in Spain on November 6, 2012. Abstract: The real-time patch (which provides CONFIG_PREEMPT_RT), has been around since 2005. Started by Ingo Molnar and maintained by Thomas Gleixner and several others, it has grown from a hobby RTOS into a very serious contender. Several distributions (Red Hat, SuSE, Debian, Ubuntu) supply a kernel version that includes this patch. The embedded world has started adding the -rt patch to their own devices that they ship. But do the embedded developers understand what the -rt patch supplies? Programming for real time, and especially when writing kernel code requires special knowledge to avoid real time traps. This talk will explain what the real time patch provides and special programming tips that will ensure embedded developers will get the best from their devices. He goes through the following key […]

January 9, 2013 by Jean-Luc Aufranc (CNXSoft) - 3 Comments

Piglit OpenGL Driver Testing Framework Now Works with ARM Linux & OpenGL ES

Piglit is a collection of automated tests for OpenGL implementations that aims at improving the quality of open source OpenGL drivers by providing developers with a simple means to perform regression tests. ARM SoCs that come with a GPU usually (always?) supports OpenGL ES however. That’s why, Tom Gall (Linaro) has modified Piglit in order to bring this test suite to ARM Linux and OpenGL ES. There are about 6,900 OpenGL tests in Piglit, and currently 1,047 Piglit (OpenGL ES) tests can run on ARM . Tom also explains that piglit developers are now using waffle, a cross-platform C library that allows one to defer selection of GL API and window system until runtime. This will allow your to select the variation of the GL API (GL, GL ES) and windowing system (X11, Wayland…) you want to use at runtime. The code is still heavily modified, but it’s in the […]

December 13, 2012March 27, 2013 by Jean-Luc Aufranc (CNXSoft) - 4 Comments

Running Ubuntu in Android with ODROID-X Development Board

I’ve had several people asking me about running Linux on Android in the last few months, but I did not look into it into details, because I thought we would just be able to run server apps. That is until Rohith left a comment on CNX Software Facebook timeline, that it’s possible to run Linux in Android, and access the user interface via VNC (sort of simple, but I did not think of it). You probably need at least 1GB of memory and a multi-core processor to run this sort of setup correctly, so I finally decided to give it a try by running Ubuntu 12.04 with Unity interface in ODROID-X development board. I mainly followed the instructions available at http://linuxonandroid.org/ and inside the Android app. Most of the steps I followed can also be replicated on other rooted Android hardware platforms. Apart from Ubuntu 10.04 & 12.04, you can […]

December 13, 2012December 13, 2012 by Jean-Luc Aufranc (CNXSoft) - 11 Comments

Getting Started with Infineon XMC4500 Relax Lite Kit and DAVE 3 IDE

Infineon Relax Lite Kit is a 10 Euros development kit based on Infineon XMC4500 Cortex M4 MCU with 160 KB SRAM and 1 MB flash, and featuring 2 USB OTG ports for debugging and powering up the board, 3 buttons (including reset), 2 LEDs, and 2 headers (through holes) giving access to the signals from the MCU such SPI, I2C, I2S, UART, CAN, ADC, DAC and PMW. The kit if available online via Hitec, but unless you live in Germany, this is not an interesting option, as international shipping costs over 100 Euros. So you’d better check local distributors in your country. The package only comes with the board, and you’ll need a USB to microUSB to power the board. To get started, simply connect the board via the USB cable to one of the USB OTG connectors, and to a Windows PC. The power LED (green) should lit up, […]