Bitfield('enables', 1,
                 Bitfield.Bit('receive_message_queue_interrupt', 1, 0),
                 Bitfield.Bit('event_message_buffer_full_interrupt', 1, 0),
                 Bitfield.Bit('event_message_buffer', 1, 0),
                 Bitfield.Bit('system_event_logging', 1, 0),