Call MICROPY_EVENT_POLL_HOOK even on very short delays so that busy loops
that call sleep_ms still yield to events and other threads.
See related issue #5344.
Replace "master" with "controller" and "slave" with "peripheral" in
comments, errors, and debug messages.
Add CONTROLLER and PERIPHERAL constants to pyb.SPI and pyb.I2C classes;
retain MASTER and SLAVE constants for backward compatiblity.
This commit adds I2S protocol support for the esp32 and stm32 ports, via
a new machine.I2S class. It builds on the stm32 work of blmorris, #1361.
Features include:
- a consistent I2S API across the esp32 and stm32 ports
- I2S configurations supported:
- master transmit and master receive
- 16-bit and 32-bit sample sizes
- mono and stereo formats
- sampling frequency
- 3 modes of operation:
- blocking
- non-blocking with callback
- uasyncio
- internal ring buffer size can be tuned
- documentation for Pyboards and esp32-based boards
- tested on the following development boards:
- Pyboard D SF2W
- Pyboard V1.1
- ESP32 with SPIRAM
- ESP32
Signed-off-by: Mike Teachman <mike.teachman@gmail.com>
The ADC_FIRST_GPIO_CHANNEL and ADC_LAST_GPIO_CHANNEL macros are no longer
needed. Instead the pin_adcX table (X = 1, 2, 3) is now generated to be
the exact size needed for a given MCU, and MP_ARRAY_SIZE(pin_adcX) is used
to determine the upper bound.
This commit also allows CPU pins to be excluded from ADC configuration if
they are hidden by prefixing their name with a "-".
Signed-off-by: Damien George <damien@micropython.org>
* Modify common functions in adc.c to accept ADC handle.
* Most external channels are connected to ADC12 which is used by default.
* For ADCAll (internal channels) ADC3 is used instead.
* Issue #4435 is possibly related (at least partially fixed).
This adds a call to mp_deinit() in the main function of the STM32 port.
This enables the use of MICROPY_PORT_DEINIT_FUNC on that port, as well as
cleaning up the GIL if threading is enabled.
Previous behaviour was: if boot.py had an exception then main.py would
still run, which is arguably unexpected behaviour.
This commit changes the behaviour so main.py is not run if boot.py has an
error.
Signed-off-by: Damien George <damien@micropython.org>
It reschedules the BT HCI poll soft timer so that it is called exactly when
the next timer expires.
Signed-off-by: Damien George <damien@micropython.org>
Instead of using systick the BT subsystem is now scheduled using a soft
timer. This means it is scheduled only when it is enabled.
Signed-off-by: Damien George <damien@micropython.org>
And call mp_pairheap_init_node() in soft_timer_static_init() so that
reinsert can be called after static_init.
Signed-off-by: Damien George <damien@micropython.org>
This introduces a new macro to get the main thread and uses it to ensure
that asynchronous exceptions such as KeyboardInterrupt (CTRL+C) are only
scheduled on the main thread. This is more deterministic than being
scheduled on a random thread and is more in line with CPython that only
allow signal handlers to run on the main thread.
Fixes issue #7026.
Signed-off-by: David Lechner <david@pybricks.com>
This moves mp_pending_exception from mp_state_vm_t to mp_state_thread_t.
This allows exceptions to be scheduled on a specific thread.
Signed-off-by: David Lechner <david@pybricks.com>
With GCC 11 there is now a warning about array bounds of OTP-mac, due to
the OTP being a literal address.
Signed-off-by: Damien George <damien@micropython.org>
Leaving the bootloader from an IRQ (eg USB or I2C IRQ) will not work if
MBOOT_LEAVE_BOOTLOADER_VIA_RESET is disabled, ie if mboot jumps directly to
the application. This is because the CPU will still be in IRQ state when
the application starts and IRQs of lower priority will be blocked.
Fix this by setting a flag when the bootloader should finish, and exit the
bootloader always from the main (top level) thread.
This also improves the USB behaviour of mboot: it no longer abruptly
disconnects when the manifest command is sent.
Signed-off-by: Damien George <damien@micropython.org>
RX and CTS are the input pins and pull-ups are enabled so they don't cause
a problem if left unconnected. But the output pins don't need a pull up
(they were originally all configured with pull up in commit
8f7491a109).
If needed, the pull-ups can be disabled in Python using machine.Pin after
the UART is constructed.
See issue #4369.
Signed-off-by: Damien George <damien@micropython.org>
The DMA driver will turn off DMA if it hasn't been used for an amount of
time (to save power). The SDIO driver for cyw43 WLAN was not informing the
DMA driver that it was using DMA and there was a chance that the DMA would
turn off in the middle of an SDIO DMA transfer. The symptoms of this would
be printing of SDIO error messages and a failure to communicate with the
cyw43 WLAN module.
This commit fixes this issue by changing the SDIO driver to use the
dma_nohal_XXX API to initialise and start the DMA.
Signed-off-by: Damien George <damien@micropython.org>
A board can now customise mboot with:
- MBOOT_LED1, MBOOT_LED2, MBOOT_LED3, MBOOT_LED4: if it needs to have
different LEDs for mboot compared to the application
- MBOOT_BOARD_LED_INIT: if it needs a fully customised LED init function
- MBOOT_BOARD_LED_STATE: if it needs a fully customised LED state-setting
function
- MBOOT_BOARD_GET_RESET_MODE: if it needs a fully customised function to
get the reset mode
With full customisation, the only requirement is a single LED to show the
status of the bootloader (idle, erasing, flashing, etc), which can be
configured to do nothing if needed.
Signed-off-by: Damien George <damien@micropython.org>
It is enabled by default to get the standard behaviour of doing a reset
after it is finished, but can be disabled by a board to jump straight to
the application (likely the board needs to use MBOOT_BOARD_CLEANUP to make
this work).
The application is passed a reset mode of BOARDCTRL_RESET_MODE_BOOTLOADER
if the bootloader was active and entered via a jump.
Signed-off-by: Damien George <damien@micropython.org>
This new logic is equivalent to the old logic when the only possibilities
for reset_mode are NORMAL, SAFE_MODE and FILESYSTEM, which is the standard
case. But the new logic also allows other reset_mode values (eg
BOOTLOADER) to run boot.py and main.py.
Signed-off-by: Damien George <damien@micropython.org>
When disabled the bootloader is entered via a direct jump. When enabled
the bootloader is entered via a system reset then a jump. It's enabled by
default to retain the existing behaviour, which is the recommended way.
Signed-off-by: Damien George <damien@micropython.org>
This can now be selected by setting MICROPY_HW_SDIO_SDMMC, which defaults
to 1, ie SDMMC1. The pins can also be selected and default to the standard
C8/C9/C10/C11/C12/D2.
This can now be selected by setting MICROPY_HW_SDCARD_SDMMC, which defaults
to 1, ie SDMMC1. This commit also renames the SD pin configuration macros
from MICROPY_HW_SDMMC2_xxx to MICROPY_HW_SDCARD_xxx, as well as renaming
MICROPY_HW_SDMMC_BUS_WIDTH to MICROPY_HW_SDCARD_BUS_WIDTH.
Signed-off-by: Damien George <damien@micropython.org>
A board can now define MBOOT_TEXT0_ADDR to place mboot at a location other
than 0x08000000. This can be useful if, for example, there is already a
different bootloader on the device.
Signed-off-by: Damien George <damien@micropython.org>
A board can now define MBOOT_LD_FILES (at the Makefile-level) to specify
custom linker scripts. And stm32_generic.ld has been split into 2 pieces
so one or the other can be reused (usually stm32_sections.ld wolud be
reused by a board, and stm32_memory.ld redefined).
Signed-off-by: Damien George <damien@micropython.org>
A board can now use BUILDING_MBOOT at the Makefile-level to do things
conditional on building mboot, for example add source files to SRC_C.
Signed-off-by: Damien George <damien@micropython.org>
Commit 1e297c8898 introduced a bug where the
very first reset-mode state on the LEDs was not shown, because prior to
that commit the first reset-mode state was the same as the initial LED
state (green on, others off) and update_reset_mode() was called after
setting this initial LED state.
This is fixed in this commit by changing the update_reset_mode() loop so
that it displays the current reset mode before doing the delay.
Signed-off-by: Damien George <damien@micropython.org>
And use the same boardctrl.h header for both the application and mboot so
these constants are consistent.
Signed-off-by: Damien George <damien@micropython.org>
This adds support for making static (ie not on the Python GC heap) soft
timers. This can be useful for a board to define a custom background
handler, or eventually for BLE/network processing to use instead of systick
slots; it will be more efficient using soft timer for this.
The main issue with using the existing code for static soft timers is that
it would combine heap allocated and statically allocated soft_timer_entry_t
instances in the same pairing-heap data structure. This would prevent the
GC from tracing some of the heap allocated entries (because the GC won't
follow pointers outside the heap).
This commit makes it so that soft timer entries are explicitly marked,
instead of relying on implicit marking by having the root of the pairing
heap in the root pointer section. Also, on soft reset only the heap-
allocated soft timers are deleted from the pairing heap, leaving the
statically allocated ones.
Signed-off-by: Damien George <damien@micropython.org>
Improvements are:
- Default period is 1000ms with callback disabled.
- if period is not specified then it's not updated (previously, if period
was not specified then it was set to -1 and running the timer callback as
fast as possible, making the REPL unresponsive).
- Use uint64_t to compute delta_ms, and raise a ValueError if the period is
too large.
- If callback is not specified then it's not updated.
- Specifying None for the callback will disable the timer.
Signed-off-by: Damien George <damien@micropython.org>
This function includes the UART prescaler in the calculation (if it has
one, eg on H7 and WB MCUs).
Signed-off-by: Damien George <damien@micropython.org>
The STM32WB has a problem when address resolution is enabled: under certain
conditions the MCU can get into a state where it draws an additional 10mA
or so and eventually ends up with a broken BLE RX path in the silicon. A
simple way to reproduce this is to enable address resolution (which is the
default for NimBLE) and start the device advertising. If there is enough
BLE activity in the vicinity then the device will at some point enter the
bad state and, if left long enough, will have permanent BLE RX damage.
STMicroelectronics are aware of this issue. The only known workaround at
this stage is to not enable address resolution, which is implemented by
this commit.
Work done in collaboration with Jim Mussared aka @jimmo.
Signed-off-by: Damien George <damien@micropython.org>
Prior to this commit, if C2 was busy (eg lots of BLE activity) then it may
not have had time to respond to the notification on the IPCC_CH_MM channel
by the time additional memory was available to put on that buffer. In such
a case C1 would modify the free buffer list while C2 was potentially
accessing it, and this would eventually lead to lost memory buffers (or a
corrupt linked list). If all buffers become lost then ACL packets
(asynchronous events) can no longer be delivered from C2 to C1.
This commit fixes this issue by waiting for C2 to indicate that it has
finished using the free buffer list.
Work done in collaboration with Jim Mussared aka @jimmo.
Signed-off-by: Damien George <damien@micropython.org>
STM32L476RG MCU of NUCLEO_L476RG board has 6 UART/USART units in total
(USART1, USART2, USART3, UART4, UART5 and LPUART1), but only UART2,
connected to REPL, was defined and available in Python code.
Defined are all 5 remaining UART/USART units including LPUART1.
Signed-off-by: Alexander Ziubin aziubin@googlemail.com
This commit simplifies the customisation of the main MicroPython execution
loop (4 macros are reduced to 2), and allows a board to have full control
over the execution (or not) of boot.py and main.py.
For boards that use the default start-up code, there is no functional
change in this commit.
Signed-off-by: Damien George <damien@micropython.org>
Support for C++ was added in 97960dc7de but
that commit didn't include the C++ exception handling table in the binary
firmware image. This commit fixes that.
Signed-off-by: Damien George <damien@micropython.org>
The GNU Make dir command uses spaces as item separator so it does not
work for e.g building the STM32 port on Cygwin with a default Arm
installation in "c:/program files (x86)/GNU Arm Embedded Toolchain".
Fix by using POSIX dirname on a quoted path instead.
This allows the user to enable wake-up sources using the EWUP bits, on F7
MCUs.
Disabling the wake-up sources while clearing the wake-up flags follows the
reference manual and ST examples.
state.reset_mode is updated by `MICROPY_BOARD_BEFORE_SOFT_RESET_LOOP` but
not passed to `init_flash_fs`, and so factory reset is not executed on
boards that do not have a bootloader. This bug was introduced by
4c3976bbcaFixes#6903.
A corrupt filesystem may lead to a request for a block which is out of
range of the block device limits. Return an error instead of passing the
request down to the lower layer.
Two of the defaults have also changed in this commit:
- MICROPY_HW_RFCORE_BLE_LSE_SOURCE changed from 1 to 0, which configures
the LsSource to be LSE (needed due to errata 2.2.1).
- MICROPY_HW_RFCORE_BLE_VITERBI_MODE changed from 0 to 1, which enables
Viterbi mode, following all the ST examples.
Signed-off-by: Damien George <damien@micropython.org>
These ports already have uzlib enabled so this additional ubinascii.crc32
function only costs about 90 bytes of flash.
Signed-off-by: Damien George <damien@micropython.org>
Add LPUART1 as a standard UART. No low power features are supported, yet.
LPUART1 is enabled as the next available UART after the standard U(S)ARTs:
STM32WB: LPUART1 = UART(2)
STM32L0: LPUART1 = UART(6)
STM32L4: LPUART1 = UART(6)
STM32H7: LPUART1 = UART(9)
On all ports: LPUART1 = machine.UART('LP1')
LPUART1 is enabled by defining MICROPY_HW_LPUART1_TX and
MICROPY_HW_LPUART1_RX in mpconfigboard.h.
Signed-off-by: Chris Mason <c.mason@inchipdesign.com.au>
So that mboot can be used to program encrypted/signed firmware to regions
of flash that are not the main application, eg that are the filesystem.
Signed-off-by: Damien George <damien@micropython.org>
The default for these is to enable them, but they can now be disabled
individually by a board configuration.
Signed-off-by: Damien George <damien@micropython.org>
If a board defines USBD_VID then that will be used instead of the default.
And then the board must also define all USBD_PID_xxx values that it needs.
Signed-off-by: Damien George <damien@micropython.org>
This allows changing the baudrate of the UART without reinitialising it
(reinitialising can lead to spurious characters sent on the TX line).
Signed-off-by: Damien George <damien@micropython.org>
To simplify config, there's no need to specify MP_PLAT_PRINT_STRN if it's
the same as the default definition in py/mpconfig.h.
Signed-off-by: Damien George <damien@micropython.org>
With mboot encrpytion and fsload enabled, the DEBUG build -O0 compiler
settings result in mboot no longer fitting in the 32k sector. This commit
changes this to -Og which also brings it into line with the regular stm32
build.
MCUs with device-only USB peripherals (eg L0, WB) do not implement (at
least not in the ST HAL) the HAL_PCD_DisconnectCallback event. So if a USB
cable is disconnected the USB driver does not deinitialise itself
(usbd_cdc_deinit is not called) and the CDC driver can stay in the
USBD_CDC_CONNECT_STATE_CONNECTED state. Then if the USB was attached to
the REPL, output can become very slow waiting in usbd_cdc_tx_always for
500ms for each character.
The disconnect event is not implemented on these MCUs but the suspend event
is. And in the situation where the USB cable is disconnected the suspend
event is raised because SOF packets are no longer received.
The issue of very slow output on these MCUs is fixed in this commit (really
worked around) by adding a check in usbd_cdc_tx_always to see if the USB
device state is suspended, and, if so, breaking out of the 500ms wait loop.
This should also help all MCUs for a real USB suspend.
A proper fix for MCUs with device-only USB would be to implement or somehow
synthesise the HAL_PCD_DisconnectCallback event.
See issue #6672.
Signed-off-by: Damien George <damien@micropython.org>
Don't clear the IPCC channel flag until we've actually handled the incoming
data, or else the wireless firmware may clobber the IPCC buffer if more
data arrives. This requires masking the IRQ until the data is handled.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
It's enabled by default to retain the existing behaviour. A board can
disable this option if it manages mounting the filesystem itself, for
example in frozen code.
Signed-off-by: Damien George <damien@micropython.org>
Changes are:
- refactor to use new _create_element function
- support extended version of MOUNT element with block size
- support STATUS element
Signed-off-by: Damien George <damien@micropython.org>
This new element takes the form: (ELEM_TYPE_STATUS, 4, <address>). If this
element is present in the mboot command then mboot will store to the given
address the result of the filesystem firmware update process. The address
can for example be an RTC backup register.
Signed-off-by: Damien George <damien@micropython.org>
Instead it is now passed in as an optional parameter to the ELEM_MOUNT
element, with a compile-time configurable default.
Signed-off-by: Damien George <damien@micropython.org>
The superblock for littlefs is in block 0 and 1, but block 0 may be erased
or partially written, so block 1 must be checked if block 0 does not have a
valid littlefs superblock in it.
Prior to this commit, if block 0 did not contain a valid littlefs
superblock (but block 1 did) then the auto-detection would fail, mounting a
FAT filesystem would also fail, and the system would reformat the flash,
even though it may have contained a valid littlefs filesystem. This is now
fixed.
Signed-off-by: Damien George <damien@micropython.org>
To match the definition of GENERATE_PACK_DFU, so a board can customise the
location/name of this file if needed.
Signed-off-by: Damien George <damien@micropython.org>
To have at least one board configured with MBOOT_ENABLE_PACKING, for CI
testing purposes and demonstration of the feature.
Signed-off-by: Damien George <damien@micropython.org>
This commit adds support to stm32's mboot for signe, encrypted and
compressed DFU updates. It is based on inital work done by Andrew Leech.
The feature is enabled by setting MBOOT_ENABLE_PACKING to 1 in the board's
mpconfigboard.mk file, and by providing a header file in the board folder
(usually called mboot_keys.h) with a set of signing and encryption keys
(which can be generated by mboot_pack_dfu.py). The signing and encryption
is provided by libhydrogen. Compression is provided by uzlib. Enabling
packing costs about 3k of flash.
The included mboot_pack_dfu.py script converts a .dfu file to a .pack.dfu
file which can be subsequently deployed to a board with mboot in packing
mode. This .pack.dfu file is created as follows:
- the firmware from the original .dfu is split into chunks (so the
decryption can fit in RAM)
- each chunk is compressed, encrypted, a header added, then signed
- a special final chunk is added with a signature of the entire firmware
- all chunks are concatenated to make the final .pack.dfu file
The .pack.dfu file can be deployed over USB or from the internal filesystem
on the device (if MBOOT_FSLOAD is enabled).
See #5267 and #5309 for additional discussion.
Signed-off-by: Damien George <damien@micropython.org>
Prior to this fix, the final piece of data in a compressed file may have
been lost when decompressing.
Signed-off-by: Damien George <damien@micropython.org>
Mboot builds do not use the external SPI flash in caching mode, and
explicitly disabling it saves RAM and a small bit of flash.
Signed-off-by: Damien George <damien@micropython.org>
This only needs to be enabled if a board uses FAT FS on external SPI flash.
When disabled (and using external SPI flash) 4k of RAM can be saved.
Signed-off-by: Damien George <damien@micropython.org>
When littlefs is enabled extended reading must be supported, and using this
function to read the first block for auto-detection is more efficient (a
smaller read) and does not require a cached SPI-flash read.
Signed-off-by: Damien George <damien@micropython.org>
These functions enable SDRAM data retention in stop mode. Example usage,
in mpconfigboard.h:
#define MICROPY_BOARD_ENTER_STOP sdram_enter_low_power();
#define MICROPY_BOARD_LEAVE_STOP sdram_leave_low_power();
Calculate the bit timing from baudrate if provided, allowing sample point
override. This makes it a lot easier to make CAN work between different
MCUs with different clocks, prescalers etc.
Tested on F4, F7 and H7 Y/V variants.
This much buffer space is required for CDC data out endpoints to avoid any
buffer overflows when the USB CDC is saturated with data.
Signed-off-by: Damien George <damien@micropython.org>
The -Og optimisation level produces a more realistic build, gives a better
debugging experience, and generates smaller code than -O0, allowing debug
builds to fit in flash.
This commit also assigns variables in can.c to prevent warnings when -Og is
used, and builds a board in CI with DEBUG=1 enabled.
Signed-off-by: Damien George <damien@micropython.org>
Allows reserving CAN, I2C, SPI, Timer and UART peripherals. If reserved
the peripheral cannot be accessed from Python.
Signed-off-by: Damien George <damien@micropython.org>
Even though IRQs are disabled this seems to be required on H7 Rev Y,
otherwise Systick interrupt triggers and the MCU leaves the stop mode
immediately.
This commit saves OSCs/PLLs state before STOP mode and restores them on
exit. Some boards use HSI48 for USB for example, others have PLL2/3
enabled, etc.
Also known as L2CAP "connection oriented channels". This provides a
socket-like data transfer mechanism for BLE.
Currently only implemented for NimBLE on STM32 / Unix.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Hardware I2C implementations must provide a .init() protocol method if they
want to support reconfiguration. Otherwise the default is that i2c.init()
raises an OSError (currently the case for all ports).
mp_machine_soft_i2c_locals_dict is renamed to mp_machine_i2c_locals_dict to
match the generic SPI bindings.
Fixes issue #6623 (where calling .init() on a HW I2C would crash).
Signed-off-by: Damien George <damien@micropython.org>
This fixes the build for non-STM32WB based boards when the NimBLE submodule
has not been fetched, and also allows STM32WB boards to build with BLE
disabled.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This is needed to moderate concurrent access to the internal flash, as
while an erase/write is in progress execution will stall on the wireless
core due to the bus being locked.
This implements Figure 10 from AN5289 Rev 3.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This commit switches the STM32WB HCI interface (between the two CPUs) to
require the use of MICROPY_PY_BLUETOOTH_USE_SYNC_EVENTS, and as a
consequence to require NimBLE. IPCC RX IRQs now schedule the NimBLE
handler to run via mp_sched_schedule.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This changes stm32 from using PENDSV to run NimBLE to use the MicroPython
scheduler instead. This allows Python BLE callbacks to be invoked directly
(and therefore synchronously) rather than via the ringbuffer.
The NimBLE UART HCI and event processing now happens in a scheduled task
every 128ms. When RX IRQ idle events arrive, it will also schedule this
task to improve latency.
There is a similar change for the unix port where the background thread now
queues the scheduled task.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This requires that the event handlers are called from non-interrupt context
(i.e. the MicroPython scheduler).
This will allow the BLE stack (e.g. NimBLE) to run from the scheduler
rather than an IRQ like PENDSV, and therefore be able to invoke Python
callbacks directly/synchronously. This allows writing Python BLE handlers
for events that require immediate response such as _IRQ_READ_REQUEST (which
was previous a hard IRQ) and future events relating to pairing/bonding.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Devices with RTC backup-batteries have been shown (very rarely) to have
incorrect RTC prescaler values. Such incorrect values mean the RTC counts
fast or slow, and will be wrong forever if the power/backup-battery is
always present.
This commit detects such a state at start up (hard reset) and corrects it
by reconfiguring the RTC prescaler values.
Signed-off-by: Damien George <damien@micropython.org>
And rename SRC_HAL -> HAL_SRC_C and SRC_USBDEV -> USBDEV_SRC_C for
consistency with other source variables.
Follow on from 0fff2e03fe
Signed-off-by: Damien George <damien@micropython.org>
The file `$(BUILD)/firmware.bin` was used by the target `deploy-stlink` and
`deploy-openocd` but it was generated indirectly by the target
`firmware.dfu`.
As this file could be used to program boards directly by a Mass Storage
copy, it's better to make it explicitly generated.
Additionally, some target are refactored to remove redundancy and be more
explicit on dependencies.
Running the update inside the soft-reset loop will mean that (on boards
like PYBD that use a bootloader) the same reset mode is used each
reset loop, eg factory reset occurs each time.
Signed-off-by: Damien George <damien@micropython.org>
The same seed will only occur if the board is the same, the RTC has the
same time (eg freshly powered up) and the first call to this function (eg
via an "import random") is done at exactly the same time since reset.
Signed-off-by: Damien George <damien@micropython.org>
Prior to this commit, the ADC calibration code was never executing because
ADVREGEN bit was set making the CR register always non-zero.
This commit changes the logic so that ADC calibration is always run when
the ADC is disabled and an ADC channel is initialised. It also uses the LL
API functions to do the calibration, to make sure it is done correctly on
each MCU variant.
Signed-off-by: Damien George <damien@micropython.org>
If the device is not connected over USB CDC to a host then all output to
the CDC (eg initial boot messages) is written to the CDC TX buffer with
wrapping, so that the most recent data is retained when the USB CDC is
eventually connected (eg so the REPL banner is displayed upon connection).
This commit fixes a bug in this behaviour, which was likely introduced in
e4fcd216e0, where the initial data in the CDC
TX buffer is repeated multiple times on first connection of the device to
the host.
Signed-off-by: Damien George <damien@micropython.org>
Josh Lloyd
David P
Damien George
Mike Teachman
iabdalkader
David Lechner
Mike Causer
plan-do-break-fix
David Michieli
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aziubin
stijn
Reinhard Feger
Peter Hinch
Braiden Kindt
Herwin Grobben
Andrew Leech
Chris Mason
Andrew Leech
Andrew Scheller
Jim Mussared
Reinhard Feger
Sébastien NEDJAR
robert