Fixes errors in the tool when 1) linking qstrs in native ARM-M code; 2)
freezing multiple files some of which use native code and some which don't.
Fixes issue #4829.
It doesn't work to tie the polling of an underlying NIC driver (eg to check
the NIC for pending Ethernet frames) with its associated lwIP netif. This
is because most NICs are implemented with IRQs and don't need polling,
because there can be multiple lwIP netif's per NIC driver, and because it
restricts the use of the netif->state variable. Instead the NIC should
have its own specific way of processing incoming Ethernet frame.
This patch removes this generic NIC polling feature, and for the only
driver that uses it (Wiznet5k) replaces it with an explicit call to the
poll function (which could eventually be improved by using a proper
external interrupt).
This adds support for SD cards using the ESP32's built-in hardware SD/MMC
host controller, over either the SDIO bus or SPI. The class is available
as machine.SDCard and using it can be as simple as:
uos.mount(machine.SDCard(), '/sd')
If the board-pin name is left empty then only the cpu-pin name is used, eg
",PA0". If the board-pin name starts with a hyphen then it's available as
a C definition but not in the firmware, eg "-X1,PA0".
The patch solves the problem where multiple Timer objects (e.g. multiple
Timer(0) instances) could initialise multiple handles to the same internal
timer. The list of timers is now maintained not for "active" timers (where
init is called), but for all timers created. The timers are only removed
from the list of timers on soft-reset (machine_timer_deinit_all).
Fixes#4078.
The board config option MICROPY_HW_USB_ENABLE_CDC2 is now changed to
MICROPY_HW_USB_CDC_NUM, and the latter should be defined to the maximum
number of CDC interfaces to support (defaults to 1).
mpy-cross uses MICROPY_DYNAMIC_COMPILER and MICROPY_EMIT_NATIVE but does
not actually need to execute native functions, and does not need
mp_fun_table. This commit makes it so mp_fun_table and all its entries are
not built when MICROPY_DYNAMIC_COMPILER is enabled, significantly reducing
the size of the mpy-cross executable and allowing it to be built on more
machines/OS's.