Entering a bootloader (ST system bootloader, or custom mboot) from software
by directly branching to it is not reliable, and the reliability of it
working can depend on the peripherals that were enabled by the application
code. It's also not possible to branch to a bootloader if the WDT is
enabled (unless the bootloader has specific provisions to feed the WDT).
This patch changes the way a bootloader is entered from software by first
doing a complete system reset, then branching to the desired bootloader
early on in the start-up process. The top two words of RAM (of the stack)
are reserved to store flags indicating that the bootloader should be
entered after a reset.
Previously the end of the heap was the start (lowest address) of the stack.
With the changes in this commit these addresses are now independent,
allowing a board to place the heap and stack in separate locations.
With this the user can select multiple logical units to expose over USB MSC
at once, eg: pyb.usb_mode('VCP+MSC', msc=(pyb.Flash(), pyb.SDCard())). The
default behaviour is the original behaviour of just one unit at a time.
Eventually these responses could be filled in by a function to make their
contents dynamic, depending on the attached logical units. But for now
they are fixed, and this patch fixes the MODE SENSE(6) responses so it is
the correct length with the correct header.
SCSI can support multiple logical units over the one interface (in this
case over USBD MSC) and here the MSC code is reworked to support this
feature. At this point only one LU is used and the behaviour is mostly
unchanged from before, except the INQUIRY result is different (it will
report "Flash" for both flash and SD card).
To use it a board should define MICROPY_PY_USSL=1 and MICROPY_SSL_MBEDTLS=1
at the Makefile level. With the provided configuration it adds about 64k
to the build.
It doesn't work to tie the polling of an underlying NIC driver (eg to check
the NIC for pending Ethernet frames) with its associated lwIP netif. This
is because most NICs are implemented with IRQs and don't need polling,
because there can be multiple lwIP netif's per NIC driver, and because it
restricts the use of the netif->state variable. Instead the NIC should
have its own specific way of processing incoming Ethernet frame.
This patch removes this generic NIC polling feature, and for the only
driver that uses it (Wiznet5k) replaces it with an explicit call to the
poll function (which could eventually be improved by using a proper
external interrupt).
If the board-pin name is left empty then only the cpu-pin name is used, eg
",PA0". If the board-pin name starts with a hyphen then it's available as
a C definition but not in the firmware, eg "-X1,PA0".
The board config option MICROPY_HW_USB_ENABLE_CDC2 is now changed to
MICROPY_HW_USB_CDC_NUM, and the latter should be defined to the maximum
number of CDC interfaces to support (defaults to 1).
Set the active MPU region to the actual size of SDRAM configured and
invalidate the rest of the memory-mapped region, to prevent errors due to
CPU speculation. Also update the attributes of the SDRAM region as per ST
recommendations, and change region numbers to avoid conflicts elsewhere in
the codebase (see eth usage).
On MCUs that have an I2C TIMINGR register, this can now be explicitly set
via the "timingr" keyword argument to the I2C constructor, for both
machine.I2C and pyb.I2C. This allows to configure precise timing values
when the defaults are inadequate.
Previously the hardware I2C timeout was hard coded to 50ms which isn't
guaranteed to be enough depending on the clock stretching specs of the I2C
device(s) in use.
This patch ensures the hardware I2C implementation honors the existing
timeout argument passed to the machine.I2C constructor. The default
timeout for software and hardware I2C is now 50ms.
Recent gcc versions (at least 9.1) give a warning about using "sp" in the
clobber list. Such code is removed by this patch. A dedicated function is
instead used to set SP and branch to the bootloader so the code has full
control over what happens.
Fixes issue #4785.
Before this change, if the USB was reconnected it was possible that some
characters in the TX buffer were retransmitted because tx_buf_ptr_out and
tx_buf_ptr_out_shadow were reset while tx_buf_ptr_in wasn't. That
behaviour is fixed here by retaining the TX buffer state across reconnects.
Fixes issue #4761.
The new function factory_reset_make_files() populates the given filesystem
with the default factory files. It is defined with weak linkage so it can
be overridden by a board.
This commit also brings some minor user-facing changes:
- boot.py is now no longer created unconditionally if it doesn't exist, it
is now only created when the filesystem is formatted and the other files
are populated (so, before, if the user deleted boot.py it would be
recreated at next boot; now it won't be).
- pybcdc.inf and README.txt are only created if the board has USB, because
they only really make sense if the filesystem is exposed via USB.
It's more common to need non-blocking behaviour when reading from a UART,
rather than having a large timeout like 1000ms (the original behaviour).
With a large timeout it's 1) likely that the function will read forever if
characters keep trickling it; or 2) the function will unnecessarily wait
when characters come sporadically, eg at a REPL prompt.
The alternate function pin allocations are different to other NUCLEO-144
boards. This is because the STM32F413 has a very high peripheral count:
10x UART, 5x SPI, 3x I2C, 3x CAN. The pinout was chosen to expose all
these devices on separate pins except CAN3 which shares a pin with UART1
and SPI1 which shares pins with DAC.
Damien George
Chris Mason
Andrew Leech
iabdalkader