# Contents of This Book

This document introduces several concepts that can be used in bare-metal development as well as shows how they can be implemented using features of latest (at the time of writing) C++11 standard.

The code of generic components is implemented as part of “Embedded C++ Library” project called “embxx” and can be found at <https://github.com/arobenko/embxx>. It has GPLv3 licence.

There is also a project that implements multiple simple bare metal applications using [embxx](https://github.com/arobenko/embxx) which can run on RaspberryPi platform. The source code can be found at <https://github.com/arobenko/embxx_on_rpi>. It also has GPLv3 licence.

Both projects require gcc version 4.7 or higher, because of C++11 support requirement. They also use [CMake](http://www.cmake.org) as their build system. The code has been tested with following free toolchains:

* [GNU Tools for ARM Embedded Processors](https://launchpad.net/gcc-arm-embedded) on Launchpad
* [Sourcery CodeBench Lite Edition](http://www.mentor.com/embedded-software/sourcery-tools/sourcery-codebench/editions/lite-edition/)

The whole document is ARM platform centric. At this moment I do not try to cover anything else.

To compile Raspberry Pi example applications in Linux environment use the following steps: 1. Checkout [embxx\_on\_rpi](https://github.com/arobenko/embxx_on_rpi) project

```
    > git clone https://github.com/arobenko/embxx_on_rpi.git
    > cd embxx_on_rpi
```

1. Create separate build directory and cd to it

   ```
    > mkdir build
    > cd build
   ```
2. Generate makefiles

   ```
    > cmake ..
   ```

   Note that last parameter to cmake is relative or absolute path to the root of the source tree.

   Also note that [embxx](https://github.com/arobenko/embxx) library will be checked out as external git submodule during this process.
3. Build the applications

   ```
    > make
   ```
4. Take the generated image from `<build_dir>/image/<app_name>/kernel.img`

The CMake provides the following build types, which I believe are self-explanatory:

* None (default)
* Debug
* Release
* MinSizeRel
* RelWithDebInfo

To specify the required build type use `-DCMAKE_BUILD_TYPE=<value>` option of cmake utility:

> cmake -DCMAKE\_BUILD\_TYPE=Release ..

If no build type is specified, the default one is **None**, which is similar to **Debug**, but without “-g” compilation option, i.e. no optimisations and no debugging information is generated.

It is possible to specify the cross-compilation toolchain prefix. By default `arm-none-eabi-` is expected, i.e. `arm-none-eabi-gcc`, `arm-none-eabi-g++` and `arm-none-eabi-as` are used to compile the sources. If these utilities cannot be found in environment search paths, then you should specify the prefix passing `-DCROSS_COMPILE=<prefix>` option to cmake:

> cmake -DCROSS\_COMPILE=/opt/arm-none-eabi-2013.05/bin/arm-none-eabi- ..

To see the commands used to compile the sources, prefix `make` with `VERBOSE=1`:

> VERBOSE=1 make

The [embxx](https://github.com/arobenko/embxx) library has doxygen generated documentation. It can be found [here](https://dl.dropboxusercontent.com/u/46999418/embxx/index.html).


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