EventCheckers
(On Main XBee PIC)

Function: TransmitBufferEmpty(void)
if TXIF flag gone from Low to High          
            Post  ES_TRMT_REG_EMPTY  to TransmitXBeeSM
            Return True
  else
  return False;


Function: Check4BalloonPopped(void)
  if BalloonMonitor Signal Pin gone from Low to High
        Post  ES_BALLOON_POPPED  to InterpretSM
        Return True;
else
  return False;


/* This is a system event defined in Framework.c*/
Function: boolean CheckSystemEvents( void )
  if Byte received
        Post  ES_XB_Msg_Rec to CheckValidSM
        Start One Second Timer to be posted to CheckValidSM
    return True;
  return False;