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+Code style
+----------
+
+1. Please use ``fixed integers``, see `stdint.h`_. Why? This library is compatible to different boards which use different architectures (16bit vs 32bit). So unfixed ``int`` has different sizes on different environments and may cause unpredictable behaviour.
+
+2. If possible: use advantages of `c++11`, e.g. `constexpr`.
+
+3. Use tab in source files. Space in examples.
+
+4. Add documentation to **every** new function or parameter. Add documentation to most steps in your source code.