`esp8266 arduino releases <https://github.com/esp8266/Arduino/releases>`__. Defaults to ``recommended``. Additional values
-``dev``: Use the latest commit from https://github.com/esp8266/Arduino, note this may break at any time
-``latest``: Use the latest *release* from https://github.com/esp8266/Arduino/releases, even if it hasn't been recommended yet.
-``recommended``: Use the recommended framework version.
-**source** (*Optional*, string): The PlatformIO package or repository to use for the framework. This can be used to use a custom or patched version of the framework.
-**platform_version** (*Optional*, string): The version of the `platformio/espressif8266 <https://github.com/platformio/platform-espressif8266/releases/>`__ package to use.
-**restore_from_flash** (*Optional*, boolean): Whether to store some persistent preferences in flash memory. Defaults to ``false``.
-**board_flash_mode** (*Optional*, string): The SPI mode of the flash chip. One of ``qio``, ``qout``, ``dio`` and ``dout``. Defaults to ``dout`` for compatibility with all chips. Note: on the next OTA update the actual flash mode is automatically detected and changed to the appropriate one.