remove YIELD
Add Declaration of data structure
Add itoa() for debugging, have to revisit it later

TODO: itoa() uses static buffer, switch to external buffer.
Add simple test task for L3G4200D, need more filter to signal.
motor: Change PULSE calculation in Open drain mode.

Original version get wrong duty cycle (complementary value)
Merge branch 'master' of github.com:Eddy0402/firmware