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class WLAN -- control built-in WiFi interfaces

docs/library/network.WLAN.rst

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.. currentmodule:: network .. _network.WLAN:

class WLAN -- control built-in WiFi interfaces

This class provides a driver for WiFi network processors. Example usage::

import network
# enable station interface and connect to WiFi access point
nic = network.WLAN(network.WLAN.IF_STA)
nic.active(True)
nic.connect('your-ssid', 'your-key')
# now use sockets as usual

Constructors

.. class:: WLAN(interface_id)

Create a WLAN network interface object. Supported interfaces are network.WLAN.IF_STA (station aka client, connects to upstream WiFi access points) and network.WLAN.IF_AP (access point, allows other WiFi clients to connect). Availability of the methods below depends on interface type. For example, only STA interface may WLAN.connect() to an access point.

Methods

.. method:: WLAN.active([is_active])

Activate ("up") or deactivate ("down") network interface, if boolean
argument is passed. Otherwise, query current state if no argument is
provided. Most other methods require active interface.

.. method:: WLAN.connect(ssid=None, key=None, *, bssid=None)

Connect to the specified wireless network, using the specified key.
If *bssid* is given then the connection will be restricted to the
access-point with that MAC address (the *ssid* must also be specified
in this case).

.. method:: WLAN.disconnect()

Disconnect from the currently connected wireless network.

.. method:: WLAN.scan()

Scan for the available wireless networks.
Hidden networks -- where the SSID is not broadcast -- will also be scanned
if the WLAN interface allows it.

Scanning is only possible on STA interface. Returns list of tuples with
the information about WiFi access points:

    (ssid, bssid, channel, RSSI, security, hidden)

*bssid* is hardware address of an access point, in binary form, returned as
bytes object. You can use `binascii.hexlify()` to convert it to ASCII form.

There are five values for security:

    * 0 -- open
    * 1 -- WEP
    * 2 -- WPA-PSK
    * 3 -- WPA2-PSK
    * 4 -- WPA/WPA2-PSK

and two for hidden:

    * 0 -- visible
    * 1 -- hidden

.. method:: WLAN.status([param])

Return the current status of the wireless connection.

When called with no argument the return value describes the network link status.
The possible statuses are defined as constants in the :mod:`network` module:

    * ``STAT_IDLE`` -- no connection and no activity,
    * ``STAT_CONNECTING`` -- connecting in progress,
    * ``STAT_WRONG_PASSWORD`` -- failed due to incorrect password,
    * ``STAT_NO_AP_FOUND`` -- failed because no access point replied,
    * ``STAT_CONNECT_FAIL`` -- failed due to other problems,
    * ``STAT_GOT_IP`` -- connection successful.

When called with one argument *param* should be a string naming the status
parameter to retrieve, and different parameters are supported depending on the
mode the WiFi is in.

In STA mode, passing ``'rssi'`` returns a signal strength indicator value, whose
format varies depending on the port (this is available on all ports that support
WiFi network interfaces, except for CC3200).

In AP mode, passing ``'stations'`` returns a list of connected WiFi stations
(this is available on all ports that support WiFi network interfaces, except for
CC3200).  The format of the station information entries varies across ports,
providing either the raw BSSID of the connected station, the IP address of the
connected station, or both.

.. method:: WLAN.isconnected()

In case of STA mode, returns ``True`` if connected to a WiFi access
point and has a valid IP address.  In AP mode returns ``True`` when a
station is connected. Returns ``False`` otherwise.

.. method:: WLAN.ifconfig([(ip, subnet, gateway, dns)])

Get/set IP-level network interface parameters: IP address, subnet mask, gateway and DNS server. When called with no arguments, this method returns a 4-tuple with the above information. To set the above values, pass a 4-tuple with the required information. For example::

nic.ifconfig(('192.168.0.4', '255.255.255.0', '192.168.0.1', '8.8.8.8'))

.. method:: WLAN.config('param') WLAN.config(param=value, ...)

Get or set general network interface parameters. These methods allow to work with additional parameters beyond standard IP configuration (as dealt with by AbstractNIC.ipconfig()). These include network-specific and hardware-specific parameters. For setting parameters, keyword argument syntax should be used, multiple parameters can be set at once. For querying, parameters name should be quoted as a string, and only one parameter can be queries at time::

# Set WiFi access point name (formally known as SSID) and WiFi channel
ap.config(ssid='My AP', channel=11)
# Query params one by one
print(ap.config('ssid'))
print(ap.config('channel'))

Following are commonly supported parameters (availability of a specific parameter depends on network technology type, driver, and :term:MicroPython port).

============= =========== Parameter Description ============= =========== mac MAC address (bytes) ssid WiFi access point name (string) channel WiFi channel (integer). Depending on the port this may only be supported on the AP interface. hidden Whether SSID is hidden (boolean) security Security protocol supported (enumeration, see module constants) key Access key (string) hostname The hostname that will be sent to DHCP (STA interfaces) and mDNS (if supported, both STA and AP). (Deprecated, use :func:network.hostname instead) reconnects Number of reconnect attempts to make (integer, 0=none, -1=unlimited) txpower Maximum transmit power in dBm (integer or float) pm WiFi Power Management setting (see below for allowed values) protocol (ESP32 Only.) WiFi Low level 802.11 protocol. See WLAN.PROTOCOL_DEFAULT. ============= ===========

Constants

.. data:: WLAN.PM_PERFORMANCE WLAN.PM_POWERSAVE WLAN.PM_NONE

Allowed values for the ``WLAN.config(pm=...)`` network interface parameter:

    * ``PM_PERFORMANCE``: enable WiFi power management to balance power
      savings and WiFi performance
    * ``PM_POWERSAVE``: enable WiFi power management with additional power
      savings and reduced WiFi performance
    * ``PM_NONE``: disable wifi power management

ESP32 Protocol Constants

The following ESP32-only constants relate to the WLAN.config(protocol=...) network interface parameter:

.. data:: WLAN.PROTOCOL_DEFAULT

  A bitmap representing all of the default 802.11 Wi-Fi modes supported by
  the chip. Consult `ESP-IDF Wi-Fi Protocols`_ documentation for details.

.. data:: WLAN.PROTOCOL_LR

  This value corresponds to the `Espressif proprietary "long-range" mode`_,
  which is not compatible with standard Wi-Fi devices. By setting this
  protocol it's possible for an ESP32 STA in long-range mode to connect to
  an ESP32 AP in long-range mode, or to use `ESP-NOW long range modes
  <espnow-long-range>`.

  This mode can be bitwise ORed with some standard 802.11 protocol bits
  (including `WLAN.PROTOCOL_DEFAULT`) in order to support a mix of standard
  Wi-Fi modes as well as LR mode, consult the `Espressif long-range
  documentation`_ for more details.

  Long range mode is not supported on ESP32-C2.

.. _ESP-IDF Wi-Fi Protocols: https://docs.espressif.com/projects/esp-idf/en/stable/esp32/api-guides/wifi.html#wi-fi-protocol-mode .. _Espressif proprietary "long-range" mode: .. _Espressif long-range documentation: https://docs.espressif.com/projects/esp-idf/en/stable/esp32/api-guides/wifi.html#long-range-lr