Based on his revision 2d290a24a0914be88e5ca4ac7b1018392fe75fe2
(https://github.com/djphoenix/nodemcu-firmware).
All LWIP callback handling changed to use the NodeMCU task interface
to make it usable on RTOS.
IPv4 assumptions have been removed, and this net module /should/ now
be IPv6 ready, but aside from compilation no testing has been done
in this area.
SSL integration points not touched - some work needed there once we
have an mbedTLS module.
node.dsleep() no longer takes options.
node.output() not yet supported (needs syscall registration/chaining support)
Dynamic CPU frequency changing not currently supported in the IDF.
Various chip IDs not currently available/obtainable.
Boot reason completely revamped in ESP32, will need new code.
RTOS driver evicted as it did not play nice with stdio etc.
Implemented a minimal driver to fully support Lua console on UART0. Output
on UART0 done via stdout (provided by the IDF). Input and setup handled
via driver_console/console.c. In addition to the direct input function
console_getc(), the driver also registers in the syscall tables to enable
regular stdio input functions to work (yay!). The Lua VM is still using the
direct interface since it's less overhead, but does also work when going
through stdin/fd 0.
Auto-bauding on the console is not yet functional; revisit when the UART docs
are available.
Module registration/linking/enabling moved over to be Kconfig based. See
updates to base_nodemcu/include/module.h and base_nodemcu/Kconfig for
details.
The sdk-overrides directory/approach is no longer used. The IDF is simply
too different to the old RTOS SDK - we need to adapt our code directly instead.
Everything in app/ is now unused, and will need to be gradually migrated
into components/ though it is probably better to migrate straight from the
latest dev branch.