This allows changing the frequency to: 100kHz, 200kHz, 400kHz, 800kHz,
1MHz, 2MHz, 4MHz, 8MHz, 16MHz, 32MHz, 64MHz. For frequencies 2MHz and
below, low power run (LPR) mode is enabled automatically.
Signed-off-by: Damien George <damien@micropython.org>
This is required to allow using WS firmware newer than 1.1.1 concurrently
with USB (e.g. USB VCP). It prevents CPU2 from modifying the CLK48 config
on boot.
Tested on WS=1.8 FUS=1.1.
See AN5289 and https://github.com/micropython/micropython/issues/6316
irq.h is included by py/mphal.h but it's better to be explicit, eg if mboot
uses powerctrlboot.c.
Signed-off-by: Damien George <damien@micropython.org>
Prior to this commit the systick IRQ priority was set at lowest priority on
F0/L0/WB MCUs, because it was left at the default and never configured.
This commit ensures the priority is configured and sets it to the highest
priority.
For use with F0 MCUs that don't have HSI48. Select the clock source
explicitly in mpconfigboard.h.
On the NUCLEO_F091RC board use HSE bypass when HSE is chosen because the
NUCLEO clock source is STLINK not a crystal.
Before this patch the UART baudrate on F0 MCUs was wrong because the
stm32lib SystemCoreClockUpdate sets SystemCoreClock to 8MHz instead of
48MHz if HSI48 is routed directly to SYSCLK.
The workaround is to use HSI48 -> PREDIV (/2) -> PLL (*2) -> SYSCLK.
Fixes issue #5049.
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.
