This aligns more closely with the hardware, that there are two, fixed HW
SPI peripherals. And it allows to recreate the HW SPI objects without
error, as well as create them again after a soft reset.
Fixes issue #4103.
In order to suit the more common 800KHz by default (instead of 400KHz), and
also have the same behaviour as the esp8266 port.
Resolves#4396.
Note! This is a breaking change. Anyone that has previously used the
NeoPixel class on an ESP32 board may be affected.
The original behaviour of open-drain-high was to use the open-drain mode of
the GPIO pin, and this seems to make driving a DHT more reliable. See
issue #4233.
The ESP IDF system already provides a math library, and that one is likely
to be better tuned to the Xtensa architecture. The IDF components are also
tested against its own math library, so best not to override it. Using the
system provided library also allows to easily switch to double-precision
floating point by changing MICROPY_FLOAT_IMPL to MICROPY_FLOAT_IMPL_DOUBLE.
So that the user can explicitly deactivate UART(0) if needed. See
issue #4314.
This introduces some risk to "brick" the device, if the user disables the
REPL without providing an alternative REPL (eg WebREPL), or any way to
reenable it. In such a case the device needs to be erased and
reprogrammed. This seems unavoidable, given the desire to have the option
to use the UART for something other than the REPL.
Without the static qualifier these objects will be kept by the linker even
if they are unused. So this patch saves some RAM when these features are
unused by a board.
If there are many short reads to a socket in a row (eg by readline) then
releasing and acquiring the GIL each time will give very poor throughput.
So first poll the socket to see if it has data, and if it does then don't
release the GIL.
Otherwise, if multiple threads are active, printing data to the REPL may be
very slow because in some cases only one character is output per call to
mp_hal_stdout_tx_strn.
On MCUs other than F4 the ORE (overrun error) flag needs to be cleared
independently of clearing RXNE, even though both are wired to trigger the
same RXNE IRQ. In the case that an overrun occurred it's necessary to
explicitly clear the ORE flag or else the RXNE interrupt will keep firing.
Otherwise IRQs may not be enabled for the user UART.irq() handler. In
particular this fixes the user IRQ_RXIDLE interrupt so that it triggers
even when there is no RX buffer.
The new option MICROPY_HW_SDCARD_MOUNT_AT_BOOT can now be defined to 0 in
mpconfigboard.h to allow SD hardware to be enabled but not auto-mounted at
boot. This feature is enabled by default to retain previous behaviour.
Previously, if an SD card is enabled in hardware it is also used to boot
from. While this can be disabled with a SKIPSD file on internal flash,
this wont be available at first boot or if the internal flash gets
corrupted.
Due to new webpages at nordicsemi.com, the download links
for Bluetooth LE stacks were broken.
This patch updates the links to new locations for the current
targets.
This UART_HandleTypeDef is quite large (around 70 bytes in RAM needed for
each UART object) and is not needed: instead the state of the peripheral
held in its registers provides all the required information.
The pin alternate function information is derived from ST's datasheet
https://www.st.com/resource/en/datasheet/stm32l432kc.pdf
In the datasheet, the line 2 of AF4 includes I2C2 but actually the chip
does not have I2C2 so it is removed.
As per the machine.UART documentation, this is used to set the length of
the RX buffer. The legacy read_buf_len argument is retained for backwards
compatibility, with rxbuf overriding it if provided.
