
Demonstrations for EBUS.

What is this demo doing :

    1.Any signal input to PA12, both FallingEdge and RisingEdge are detectable.
     (You can only detect FallingEdge by define 'FALLING_EN', or only detect RisingEdge by define 'RISING_EN')
	 
	2.Both FallingEdge and RisingEdge will enter interruption.
 


