typedef enum
{ 
    etConnect_Indication,
    etConnect_Confirmation,
    .
    .
    .
    etDisconnect_Confirmation,
    etLE_Connect_Indication, etLE_Connect_Confirmation, etLE_Disconnect_Indication, 
            etLE_Disconnect_Confirmation, etLE_Data_Indication, etLE_Channel_Buffer_Empty_Indication
} L2CA_Event_Type_t;