The test bed used for this application note is composed of the same hardware/software platform delivered along with the [[DESK-MX6UL-L | DESK-MX6UL-L]]. About Buildroot, the version [https://buildroot.org/downloads/buildroot-2022.05.tar.gz buildroot-2022.05] was used.
==DonwloadingVirtual Machine requirements ==The building process may requires higher resources than the original [[DESK-MX6UL-L | DESK-MX6UL-L]] MVM settings: this depends on the package selected in the <code>.config</code> file and theirs build resources. For example: building the <code>qt-webkit</code> package will require a lot of resources so it is better to add more CPUs and more RAM to the VM like the following settings: [[File:DESK-MX6UL-MVM_buildroot.png|thumb|center|600px| MVM with 10 CPU cores and 16GB of RAM]] ==Downloading, configuring and building==
This process is straightforward. Once the file [https://buildroot.org/downloads/buildroot-2022.05.tar.gz <code>buildroot-2022.05.tar.gz</code>] is downloaded and decompressed on your Linux host machine, get into the Buildroot directory, and run <code>make menuconfig</code>.
Here below a list of most important selected packages:
* '''Qt5.15''' libraries including: <code>fontconfig</code>, <code>DBus</code>, <code>qt5declarative</code>, <code>qt5multimedia</code>, <code>qt5quickcontrols</code>, <code>qt5quickcontrols2</code>, <code>qt5sensors</code>, <code>qt5serialbus</code>, <code>qt5serialport</code>, <code>qtextserialport</code>, <code>Qt SQlite</code> and the very important <code>qt5webkit</code> (and <code>qt5webchannel</code>, <code>qt5websockets</code>)** <code>qt-webwebkit-kiosk</code> browser can be used for creating a GUI with an embedded browser as a Kiosk application has been included too
* framebuffer utilities like: <code>fbset</code>, <code>fbv</code>, <code>fbgrab</code> and the <code>fb-test</code> application
The Qt5 building has an error on producing the <code>qt-webkit-kiosk</code> artifacts. Following [https://patchwork.ozlabs.org/project/buildroot/patch/20220929181350.1026033-1-thomas.ballasi@savoirfairelinux.com/ this thread] you can find a patch for fixing the issuefor the file <code>package/qt5/qt5webkit/qt5webkit.mk</code>:
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=== Use cases ===
==== node ====
Using the <code>nodejs</code> Javascript runtime it is possible to easily create an embedded webserver with few lines of code:
[[File:AXEL-ULite-nodejsFirefox.png | thumb | 600px | center | nodeJS web server]]
[[File:AXEL-ULite-buildroot-gstreamer2.png | thumb | center| 1000px| gstreamer CPU load using <code>imxpxpvideosink</code>]]
[[File:Gstreamer-pxp.png | thumb | center| 1000px| Big Buck Bunny 640x360 MPEG-4: 53% CPU load]]
==Binary artifacts ==
buildroot binary artifacts (root file system, kernel+dtb and SDK) can be downloaded - for both versions - from DAVE Embedded Systems [https://cloud.dave.eu/public/buildroot-axel-ulite cloud server]
'''N.B.''' <code>config</code> file should be renamed as <code>.config</code> in the buildroot directory before starting the build process