This new series of MCUs is similar to the L4 series with an additional
Cortex-M0 coprocessor. The firmware for the wireless stack must be managed
separately and MicroPython does not currently interface to it. Supported
features so far include: RTC, UART, USB, internal flash filesystem.
Behaviour was changed from stack to queue in
8977c7eb58, and this updates variable names
to match. Also updates other references (docs, error messages).
The new configurations MICROPY_HW_USB_MSC and MICROPY_HW_USB_HID can be
used by a board to enabled or disable MSC and/or HID. They are both
enabled by default.
__clear_cache causes a compile error when using clang. Instead use
__builtin___clear_cache which is available under both gcc and clang.
Also replace tabs with spaces in this section of code (introduced by a
previous commit).
In a non-thread build, using &_ram_end as the top-of-stack is no longer
correct because the stack is not always at the very top end of RAM. See
eg 04c7cdb668 and
3786592097. The correct value to use is
&_estack, which is the value stored in MP_STATE_THREAD(stack_top), and
using the same code for both thread and non-thread builds makes the code
cleaner.