.. _headlabel-refx-cmd-apf:

APF (Auto Parking-fence)
========================

The `AT@APF` command is used to control the Parking-fence function.

The Parking-fence refers to a virtual circular geographical fence that automatically generated when parking. When the vehicle is ignition off, the terminal will automatically set a Parking-fence with the current location as the center. The terminal will only scan whether it exits this Parking-fence. This Parking-fence will be canceled after the terminal exits the zone.

The :ref:`Record 18H <headlabel-refx-record-18>` could be generated and sent to backend server when the Paring-fence is generated or canceled.

In addition, the status of the Parking-fence (:ref:`Data 105 <headlabel-refx-data-105>`) can be inquired in real time by the subcommand **0** of the :ref:`AT@RTO <headlabel-refx-cmd-rto>` command.

.. code-block:: none

   Example:
   AT@APF=gv500cna,,1,,500,,,012F$
   +ACK:APF,123456789012345,8203,3,0,,012F,20210407101530,1234$
   AT@APF?gv500cna,,0C37$
   +QRY:APF,123456789012345,8203,3,0,1,1,,1,60,500,,,0C37,20210407101530,1234$

.. tabularcolumns:: |p{2.2em}|p{7.2em}|p{5.8em}|p{19em}|p{4.8em}|

.. table::
   :width: 100%
   :widths: auto

   +-------+----------------------------------+---------------+----------------------------------------+--------------------+
   | Parts |              Fields              | Length (Byte) |             Range/Format               |    Default         |
   +=======+==================================+===============+========================================+====================+
   | Head  | Header                           | 3             | AT@                                    | AT@                |
   +       +----------------------------------+---------------+----------------------------------------+--------------------+
   |       | Command Word                     | 3             | APF                                    | APF                |
   +       +----------------------------------+---------------+----------------------------------------+--------------------+
   |       | Leading Symbol                   | 1             | =                                      | =                  |
   +       +----------------------------------+---------------+----------------------------------------+--------------------+
   |       | Password                         | 8-16          |                                        | gv500cna           |
   +-------+----------------------------------+---------------+----------------------------------------+--------------------+
   | Body  | Reserved                         | 0             |                                        |                    |
   +       +----------------------------------+---------------+----------------------------------------+--------------------+
   |       | `Mode`                           | 1             | 0-2                                    | 0                  |
   +       +----------------------------------+---------------+----------------------------------------+--------------------+
   |       | `Check Interval`                 | <=5           | 5-86400 (seconds)                      | 60                 |
   +       +----------------------------------+---------------+----------------------------------------+--------------------+
   |       | `Radius`                         | <=6           | 100-100000 (meters)                    | 100                |
   +       +----------------------------------+---------------+----------------------------------------+--------------------+
   |       | Reserved                         | 0             |                                        |                    |
   +       +----------------------------------+---------------+----------------------------------------+--------------------+
   |       | Reserved                         | 0             |                                        |                    |
   +-------+----------------------------------+---------------+----------------------------------------+--------------------+
   | Tail  | Sequence Number                  | 4             | 0000-FFFF ('0'-'9', 'A'-'F')           |                    |
   +       +----------------------------------+---------------+----------------------------------------+--------------------+
   |       | Tail                             | 1             | $                                      | $                  |
   +-------+----------------------------------+---------------+----------------------------------------+--------------------+

- `Mode`

  - **0** - Disable. Disable the Parking-fence function.

  - **1** - Enable (Automatically triggered always).

    In this mode, every time the vehicle is ignition off, if there is no Parking-fence that has been generated, the terminal will automatically generate a new Parking-fence.

  - **2** - Enable (Automatically triggered once).

    After receiving the AT\@APF command with this mode, the terminal will generate a new Parking-fence after the vehicle is ignition off (even if it has been generated before);
    when the vehicle leaves this fence, the terminal will no longer generate a new Parking-fence until it receives a new AT\@APF command.

- `Check Interval`

    The checking interval for the Parking-fence event. For power consumption reasons, the terminal will turn off GNSS without affecting the application, in which case the terminal will temporarily stop detecting Parking-fence events until this interval is reached.

- `Radius`

  The radius of the circular Parking-fence region.