This patch allows to use lwIP as the implementation of the usocket module,
instead of the existing socket-multiplexer that delegates the entire TCP/IP
layer to the NIC itself.
This is disabled by default, and enabled by defining MICROPY_PY_LWIP to 1.
When enabled, the lwIP TCP/IP stack will be included in the build with
default settings for memory usage and performance (see
lwip_inc/lwipopts.h). It is then up to a particular NIC to register itself
with lwIP using the standard lwIP netif API.
By default the stm module is included in the build, but a board can now
define MICROPY_PY_STM to 0 to not include this module. This reduces the
firmware by about 7k.
This patch takes the software SPI implementation from extmod/machine_spi.c
and moves it to a dedicated file in drivers/bus/softspi.c. This allows the
SPI driver to be used independently of the uPy runtime, making it a more
general component.
This file mirrors py/mpconfig.h but for board-level config options. It
provides a default configuration, to be overridden by a specific
mpconfigboard.h file, as well as setting up certain macros to automatically
configure a board.
This patch adds in internal config value MICROPY_HW_ENABLE_HW_I2C that is
automatically configured, and enabled only if one or more hardware I2C
ports are defined in the mpconfigboard.h file. If none are defined then
the pyb.I2C class is excluded from the build, along with all supporting
code. The machine.I2C class will still be available for software I2C.
Disabling all hardware I2C on an F4 board saves around 10,000 bytes of code
and 200 bytes of RAM.
The legacy function pyb.repl_uart() is still provided and retains its
original behaviour (it only accepts a UART object). uos.dupterm() will now
accept any object with write/readinto methods. At the moment there is just
1 dupterm slot.
Prior to this patch calling pyb.Timer(id) would always create a new timer
instance, even if there was an existing one. This patch fixes this
behaviour to match other peripherals, like UART, such that constructing a
timer with just the id will retrieve any existing instances.
The patch also refactors the way timers are validated on construction to
simplify and reduce code size.
This is to keep the top-level directory clean, to make it clear what is
core and what is a port, and to allow the repository to grow with new ports
in a sustainable way.
