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diff --git a/docs/src/articles.dox b/docs/src/articles.dox
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@@ -21,6 +21,7 @@
  * @page articles Articles

  * @{

  * ChibiOS/RT Articles and Code Examples:

+ * - @subpage article_portguide

  * - @subpage article_atomic

  * - @subpage article_saveram

  * - @subpage article_interrupts

diff --git a/docs/src/portguide.dox b/docs/src/portguide.dox
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+++ b/docs/src/portguide.dox
@@ -0,0 +1,114 @@
+/*

+    ChibiOS/RT - Copyright (C) 2006-2007 Giovanni Di Sirio.

+

+    This file is part of ChibiOS/RT.

+

+    ChibiOS/RT is free software; you can redistribute it and/or modify

+    it under the terms of the GNU General Public License as published by

+    the Free Software Foundation; either version 3 of the License, or

+    (at your option) any later version.

+

+    ChibiOS/RT is distributed in the hope that it will be useful,

+    but WITHOUT ANY WARRANTY; without even the implied warranty of

+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

+    GNU General Public License for more details.

+

+    You should have received a copy of the GNU General Public License

+    along with this program.  If not, see <http://www.gnu.org/licenses/>.

+*/

+

+/**

+ * @page article_portguide Porting ChibiOS/RT for Dummies

+ * @{

+ * Porting the operating system on a new platform is one of the most common

+ * tasks. The difficulty can range from easy to very difficult depending

+ * on several factors.<br>

+ * We can divide in problem in several classes of progressively increasing

+ * difficulty:

+ * - @ref port_board

+ * - @ref port_family

+ * - @ref port_chip

+ * - @ref port_core

+ * .

+ * Another kind of port type is porting to another compiler and this is an

+ * added complexity level on the above classes. The kernel itself is portable

+ * but the port-specific code usually contains compiler specific extensions to

+ * the C language and the asm files syntax is almost never compatible.

+ *

+ * @section port_board Porting the OS to a new board

+ * This is the easiest port type, the scenario is that the specific

+ * microcontroller is already supported and a demo exists. This scenario also

+ * applies when porting the OS on a custom hardware using a supported

+ * microcontroller. This task can be easily performed with the following

+ * steps:

+ * -# Create a new directory under the ChibiOS/RT installation directory:

+ *    <code>./projects/<i>@<my_app_name@></i></code>

+ * -# Copy the microcontroller demo code under the newly created directory.

+ * -# Customize the demo. Usually there are only four files that need to

+ *    be modified:

+ *   - @p board.h This file contains the I/O pins setup for the uC, it

+ *     may also contain other board-dependent settings, as example, clock and

+ *     PLL settings. Customize this file depending on your target hardware.

+ *   - @p board.c This file contains the initialization code, it is possible

+ *     you just need to customize @p board.h and not this file. If you have

+ *     some hardware specific initialization code then put it here.

+ *   - @p Makefile You may edit this file in order to remove the test related

+ *     sources and/or add you application source files.

+ *   - @p main.c It contains the demo simple code, clean it and write your

+ *     own @p main() function here, use this file just as a template.

+ * -# Compile your application and debug.

+ * .

+ * @section port_family Porting the OS to a closely related microcontroller

+ * In this scenario all the above steps are required but an analysis must

+ * be performed to evaluate the differences between from the supported micro

+ * and the target micro. Often the micros just differ for the memory area

+ * sizes and a change to the linker script is enough (the file is usually

+ * named @p ch.ld). Chips having more or less peripherals, everything else

+ * being the same or compatible are not a problem also as long the timer and

+ * the serial peripherals used by the port do not change.<br>

+ * If there are differences in the internal peripherals, as example non

+ * compatible interrupt controllers (this happens in the LPC2000 family)

+ * or differences in UARTS, timers etc then the port falls in the following

+ * category.

+ *

+ * @section port_chip Porting the OS to another microcontroller using the same core

+ * This kind of port is required when a target microcontroller has the same

+ * core (a common example: ARM7) of a supported microcontroller but has

+ * differences in the internal peripherals.<br>

+ * If this is your case proceed as follow:

+ * -# Create a new directory under @p ./ports and name it as follow:

+ *    <code><i>@<arch@></i>-<i>@<chip@></i>[-<i>@<compiler@></i>]</code>

+ *    The compiler part can be omitted if the port uses GCC (our default).

+ *    Examples: @p ARM7-LPC236x or @p ARMCM3-STM32F103-IAR

+ * -# Copy into the newly created directory the most closely related existing

+ *    chip port.

+ * -# Rename the files in order to reflect the name of the new chip.

+ * -# Work out the differences in the drivers.

+ * -# Edit the documentation file @p port.dox, this is required if you want

+ *    to regenerate this documentation including your work.

+ * .

+ * Usually this kind of port just requires a serial driver (and those are very

+ * similar each other) and some code for the interrupt controller (this one

+ * can be part of the core port, as example the Cortex-M3 has this as standard

+ * part of the core).<br>

+ * When the chip port is completed created your application as seen in the

+ * previous sections.

+ *

+ * @section port_core Porting the OS to a whole new architecture

+ * This is the hardest scenario, the time required by core ports depends

+ * strongly by the target architecture complexity and the level of support you

+ * need for the architecture specific features.<br>

+ * As a reference, the MSP430 port took me 2 hours and it worked at the first

+ * run, it can be a reference for simple architectures, the ARM Cortex-M3 was

+ * painful instead, the architecture enforces you to implement things in a very

+ * specific way and I spent 2 week to go through all the documentation and

+ * figure out the correct way to implement the port (you can see that the

+ * preemption context switch is done in a very peculiar way because the

+ * exceptions architecture).<br>

+ * One thing is sure, port an OS to a new architecture is not an easy task and

+ * if you have the required experience for such an effort then probably you

+ * don't need any advice from me. Just follow the directory patterns and fill

+ * the OS template files, the hardest part is decide the correct and efficient

+ * way to implement the context switching.

+ */

+/** @} */