format. It is targeted at 32 bit microcontrollers, but is also fit for
other embedded systems with tight (2-10 kB ROM, <1 kB RAM) memory
constraints.(http://koti.kapsi.fi/jpa/nanopb/)

How to use the example:
	1. move examples/nanopb to bsp/xxxx/
	2. enable macro RT_USING_NANOPB in rtconfig.h
	3. regenerate the project file (scons --target=xxxx)
	4. rebuild the project