/****************************************************************************
 Module:
 	Hopping_SM.c

 Description:
 	A hierarchical state machine for the ME218B project.

 Module Variables:
	CurrentState

****************************************************************************/

/****************************************************************************
 Function RunHopping_SM
 	Takes an event to process
	Returns an event to return
****************************************************************************/
Depending on CurrentState:
	If Hopper is waiting...
		... and hopper is told to start,
            		move hopper down.
            		
	If Hopper is moving down...
		... and hopper hits bottom limit,
            		switch to move up state.
		... and it's time to dump,
            		switch to dump state.    
		... and hopper time limit expires,
            		switch to move up state.  
            		
	If Hopper is moving up...
		... and hopper hits middle limit,
            		switch to hold state.
        ... and hopper hits upper limit,
            		switch to hold state.
		... and it's time to dump,
            		swtich to dumping state.    
		... and hopper time limit expires,
            		switch to hold state.  
            		
	If Hopper is holding...
		... and hopper time limit expires,
            		switch to move down state.   
		... and it's time to dump,
            		switch to dump state.  

	If Hopper is dumping...
		... and hopper hits upper limit,
					stop hopper.
            		start a pause timer.
        ... and pause timer expires,
        			switch to move down state.
        			post an event to the main SM to start driving again.          		
                       
If we are making a state transition
    Execute exit function for current state
    Execute entry function for new state
    return ReturnEvent

End of function


/****************************************************************************
 Function StartHopping_SM
	Takes an event CurrentEvent
	Returns nothing
	Does any required initialization for this state machine
 ***************************************************************************/
If hopper is at lower limit,
	set Current State to Move Up State
Otherwise,
	set Current State to Move down State
Call RunHopping_SM with CurrentEvent
End of function


/****************************************************************************
 Function QueryHopping_SM	
	Takes nothing
	Returns the current state of the Hopping state machine
****************************************************************************/
Return the value of CurrentState
End of function	

/***************************************************************************
 'During' functions:
 ***************************************************************************/


DuringWaitState
	Entry functions: none
	Exit functions: none
	During functions: none
End of function


DuringMoveDownState
	Entry functions:
		Set the hopper motor to move DOWN
		Initialize the hopper timer for Time_HopperDown
			(in case the limit switch doesn't fire)
	Exit functions: none
	During functions: none
End of function


DuringMoveUpState
	Entry functions:
		Set the hopper motor to move UP
		Initialize the hopper timer for Time_HopperUp
			(in case the limit switch doesn't fire)
	Exit functions: none
	During functions: none
End of function


DuringHoldState
	Entry functions:
		Set the hopper motor to STOP
		Initialize the hopper timer for Time_HopperHold
	Exit functions: none
	During functions: none
End of function


DuringDumpState
	Entry functions:
		Set the hopper motor to move UP
		Initialize the hopper timer for Time_HopperDump
			(in case the limit switch doesn't fire)
	Exit functions: none
	During functions: none
End of function