This follows the pattern of how all other headers are now included, and
makes it explicit where the header file comes from. This patch also
removes -I options from Makefile's that specify the mp-readline/timeutils/
netutils directories, which are no longer needed.
Such constants are MCU specific so shouldn't be specified in the board
config file (else it leads to too much duplication of code).
This patch also adds I2C timing values for the F767/F769 for 100k, 400k
and 1MHz I2C bus frequencies.
By default the SDIO (F4) or SDMMC1 (L4, F7) is used as the SD card
peripheral, but if a board config defines MICROPY_HW_SDMMC2_CK and other
pins then the SD card driver will use SDMMC2.
With the existing timeout of 100ms the transfer would end prematurely if
the baudrate was low and the number of bytes to send was high. This patch
fixes the problem by making the timeout proportional to the number of bytes
that are being transferred.
The C nearbyint function has exactly the semantics that Python's round()
requires, whereas C's round() requires extra steps to handle rounding of
numbers half way between integers. So using nearbyint reduces code size
and potentially eliminates any source of errors in the handling of half-way
numbers.
Also, bare-metal implementations of nearbyint can be more efficient than
round, so further code size is saved (and efficiency improved).
nearbyint is provided in the C99 standard so it should be available on all
supported platforms.
The -ansi flag is used for C dialect selection and it is equivalent to -std=c90.
Because it goes right before -std=gnu99 it is ignored as for conflicting flags
GCC always uses the last one.
We can actually handle interrupts during a thread switch (because we always
have a valid stack), but only if those interrupts don't access any of the
thread state (because the state may not correspond to the stack pointer).
So to be on the safe side we disable interrupts during the very short
period of the thread state+stack switch.
Damien George
Krzysztof Blazewicz