Previous to this patch trying to construct, but not init, a UART that
didn't exist on the target board would actually succeed. Only when
initialising the UART would it then raise an exception that the UART does
not exist.
This patch adds an explicit check that the constructed UART does in fact
exist for the given board.
This follows the pattern of other peripherals (I2C, SPI) to specify the
pins using pin objects instead of a pair of GPIO port and pin number. It
makes it easier to customise the UART pins for a particular board.
These are basic drawing primitives. They work in a generic way on all
framebuf formats by calling the underlying setpixel or fill_rect C-level
primitives.
The STM32 F7 and L4 boards use significantly different code to the F4
boards so it's important to test them with CI. To keep CI build times
within a reasonable limit the STM32F4DISC board is no longer built, it's
anyway very similar to the standard F4 build for PYBv1.0.
If you have longish operations on the db (such as logging data) it may
be desirable to periodically sync the database to the disk. The added
btree.sync() method merely exposes the berkley __bt_sync function to the
user.
The constants MP_IOCTL_POLL_xxx, which were stmhal-specific, are moved
from stmhal/pybioctl.h (now deleted) to py/stream.h. And they are renamed
to MP_STREAM_POLL_xxx to be consistent with other such constants.
All uses of these constants have been updated.