Add configuration section // Resolve #19

Author: ivankravets

README.md

@@ -32,4 +32,36 @@ board = ...
 
 # Configuration
 
-Please navigate to [documentation](https://docs.platformio.org/page/platforms/asrmicro650x.html).
+## LoRaWAN
+
+LoRaWAN protocol can be configured in :ref:`projectconf` using the following syntax
+``board_build.arduino.lorawan.*`` where ``*`` is an option from the following list:
+
+| Option      | Description | Possible values | Default |
+| ----------- | ----------- | --------------- | ------- |
+| ``region`` | Region definition | ``AS923_AS1``, ``AS923_AS2``, ``AU915``, ``CN470``, ``CN779``, ``EU433``, ``EU868``, ``KR920``, ``IN865``, ``US915``, ``US915_HYBRID`` | ``US915`` |
+| ``class`` | Device class | ``CLASS_A``, ``CLASS_C`` | ``CLASS_A`` |
+| ``netmode`` | Activation method | ``OTAA``, ``ABP`` | ``OTAA`` |
+| ``adr`` | Adaptive Data Rate | ``ON``, ``OFF`` | ``ON`` |
+| ``uplinkmode`` | Uplink confirmed/unconfirmed messages | ``CONFIRMED``, ``UNCONFIRMED`` | ``CONFIRMED`` |
+| ``net_reserve`` | Don't rejoin after reset | ``ON``, ``OFF`` | ``OFF`` |
+| ``at_support`` | AT commands support | ``ON``, ``OFF`` | ``ON`` |
+| ``rgb`` | RGB light for LoRaWAN status | ``ACTIVE``, ``DEACTIVE`` | ``ACTIVE`` |
+| ``preamble_length`` | Preamble length | ``8``, ``16`` (For M00 and M00L) | ``8`` |
+| ``debug_level`` | Print LoRaWAN relevant messages print to serial port | ``NONE``, ``FREQ`` (Sending/receiving frequency), ``FREQ_AND_DIO`` (Sending/receiving frequency and DIO pin interrupt information) | ``NONE`` |
+
+
+**Example**
+
+```ini
+[env:cubecell_board]
+platform = asrmicro650x
+framework = arduino
+board = cubecell_board
+board_build.arduino.lorawan.region = EU433
+board_build.arduino.lorawan.adr = OFF
+board_build.arduino.lorawan.debug_level = FREQ_AND_DIO
+```
+
+More information about LoRaWAN configuration can be found in
+[the official CubeCell documentation](https://heltec-automation-docs.readthedocs.io/en/latest/cubecell/index.html).