<h2 id="news">Recent News</h2>
<ul>
+<li>
+ We will present the a paper <a href="https://www.osadl.org/?id=2018">Usable Simulink Embedded Coder Target for Linux</a>
+ and RPi motor control demonstartion at <a href="https://www.osadl.org/RTLWS-2014.rtlws-2014.0.html">16th Real Time Linux Workshop</a>
+ taking place on 12 and 13 October 2014 in Dusseldorf Germany.</li>
<li>
We will present the ert_linux project
at <a href="http://www.amper.cz/en/online-catalog/list-of-exhibitors.html/e9595_0-fakulta-elektrotechnicka-cvut-v-praze">Amper
</li>
</ul>
-<h2 id="linuxnative">Native Linux Real-Time and I/O Cards Support</h2>
+<h2 id="linuxnative">Native Linux Real-Time and I/O Cards and Devices Support</h2>
<p>Current version of the Linux ERT target is optimized to use the
proper Linux kernel timing mechanism with bounded maximal latencies.
on <a href="http://rtime.felk.cvut.cz/hw/index.php/Humusoft_MF6xx">DCE
HW Wiki page</a>.</p>
+<p>
+The basic blocks for <a href="can_bus/index.html">CAN messges sending and receiption</a>
+under Linux are implemented.
+</p>
+
+<h2 id="platformselect">RT-Capable Platform and Kernel</h2>
+<p>
+Standard distribution Linux kernel does not guarantee bounded latencies for many operations.
+The use of <a href="http://rt.wiki.kernel.org/">real-time variant</a> of <a href="http://en.wikipedia.org/wiki/Linux">Linux</a>
+kernel is required to make system durable. This kernel variants minimizes regions
+where switch to the highest priority (i.e. Linux ERT generated) task is blocked by
+kernel when servicing system calls for other tasks.
+</p>
+<p>
+Selection of the right version of the kernel is not enough for non-disruptive
+operation. Computer system hardware selection is critical as well. The system
+has to provide enough computational power for compiled in blocks data evaluation
+evaluation and Linux kernel services processing. Other critical disturbance sources
+are hardware caused latencies and lags in a program processing by CPU. The source
+can be bus systems load by other subsystems (i.e. graphic processor memory access,
+peripheral DMA - SSD, SD-card, Flash controller etc.). The other critical source of
+latencies in x86 based systems is <a href="http://en.wikipedia.org/wiki/System_Management_Mode">SMI</a>
+processing. The SMI enable and processing is under BIOS and motherboard vendor control
+and this problem cannot be resolved by operating system. This means that proper
+hardware selection is critical.
+</p>
+<p>
+A long period evaluation data of different combinations of Linux kernel version
+runing on many CPU architectures and boards from many vendors is <a href="http://www.osadl.org/">OSADL</a>
+<a href="http://www.osadl.org/Quality-assurance-at-the-OSADL-QA-Farm.osadl-services-qa.0.html">Quality Assurance Farm</a>.
+According to these track records carefully selected x86 or embedded GNU/Linux system can run
+real-time tasks with sampling frequencies up to 20 kHz with no losing sample per months.
+</p>
+
<h2 id="download">Source Code and Download</h2>
<dl>
<p>Lukáš Hamáček, “<b>RTW target for Linux with CANopen support</b>”, Master Thesis, Prague 2009. (<a href="dp_2009_hamacek_lukas.pdf">Pdf</a>)</p>
+<h2 id="applications">Systems Controlled Linux Target for Embedded Coder</h2>
+
+Some more information about concrete examples of controlled systems/setups:
+
+<dl>
+ <dt><b>Moving Slide</b> parallel kinematic/robot control</dt>
+ <dd>The Linux ERT target is used at Adaptive Systems Department (Academy of Sciences
+ of Czech Republic, UTIA institute) to realize control system for parallel kinematics
+ control research projects. See <a href="moving-slide/index.html">respective page for more
+ information about project</a>.
+ </dd>
+ <dt><b>Raspberry Pi</b> minimal components DC motor servo control</dt>
+ <dd><a href="http://en.wikipedia.org/wiki/Raspberry_Pi">Raspberry Pi</a> is low cost
+ hardware which does not implement any usual motor control peripherals in hardware.
+ Yet fully preemptive variant of Linux kernel latencies are so low that fast signals
+ processing in software allows to implement precise DC motor feedback control
+ for incremental encoder inputs changing up to 15 kHz.
+ See <a href="rpi-motor-control/index.html"> respective page for more information
+ about project</a>.
+ </dd>
+</ul>
+
<h2 id="contributors">Project Contributors</h2>
<dl>
projects / ert_linux_web.git / blobdiff