micropython/docs/wipy/tutorial/wlan.rst

WLAN step by step
=================

The WLAN is a system feature of the WiPy, therefore it is always enabled
(even while in ``machine.SLEEP``), except when deepsleep mode is entered.

In order to retrieve the current WLAN instance, do::

   >>> from network import WLAN
   >>> wlan = WLAN() # we call the constructor without params

You can check the current mode (which is always ``WLAN.AP`` after power up)::

   >>> wlan.mode()

Connecting to your home router
------------------------------

The WLAN network card always boots in ``WLAN.AP`` mode, so we must first configure
it as a station::

   from network import WLAN
   wlan = WLAN(mode=WLAN.STA)

Now you can proceed to scan for networks::

    nets = wlan.scan()
    for net in nets:
        if net.ssid == 'mywifi':
            print('Network found!')
            wlan.connect(net.ssid, auth=(net.sec, 'mywifikey'), timeout=5000)
            while not wlan.isconnected():
                machine.idle() # save power while waiting
            print('WLAN connection succeeded!')
            break

Assigning a static IP address when booting
------------------------------------------

If you want your WiPy to connect to your home router after boot-up, and with a fixed
IP address so that you can access it via telnet or FTP, use the following script as /flash/boot.py::

   import machine
   from network import WLAN
   wlan = WLAN() # get current object, without changing the mode

   if machine.reset_cause() != machine.SOFT_RESET:
       wlan.init(WLAN.STA)
       # configuration below MUST match your home router settings!!
       wlan.ifconfig(config=('192.168.178.107', '255.255.255.0', '192.168.178.1', '8.8.8.8'))

   if not wlan.isconnected():
       # change the line below to match your network ssid, security and password
       wlan.connect('mywifi', auth=(WLAN.WPA2, 'mywifikey'), timeout=5000)
       while not wlan.isconnected():
           machine.idle() # save power while waiting

.. note::

   Notice how we check for the reset cause and the connection status, this is crucial in order
   to be able to soft reset the WiPy during a telnet session without breaking the connection.