This applies to all machine modules which have pins as arguments. Since
machine_pin_get_id() calls pin_find(), these pin arguments may be at the
moment either integer objects or Pin objects. That allows for instance to
write
uart = UART(1, tx=Pin(4), rx=Pin(5))
instead of
uart = UART(1, tx=4, rx=5)
which is consistent with other ports. Since this handling is done at a
single place in the code, extending that scheme to accept strings for named
pins is easy.
Signed-off-by: robert-hh <robert@hammelrath.com>
The new machine_pin_find() function accepts a Pin object and a integer
object as input and returns a pin object. That can be extended later to
accept a string object, once named pins are supported.
Signed-off-by: robert-hh <robert@hammelrath.com>
The legacy driver was deprecated in IDF v5, and crashes when the ISR
handler is called. Instead of fixing the legacy code, this commit reworks
the machine.Timer class to use the low-level HAL driver.
Tested on ESP32, ESP32S2, ESP32S3 and ESP32C3. Behaviour is the same as it
was before this commit, except the way the Timer object is printed, it now
gives more useful information (timer id, mode, period in ms).
Fixes issue #11970.
Signed-off-by: Damien George <damien@micropython.org>
This is a fix for commit bccbaa92b1:
- Should only wait for WIFI_EVENT_STA_START when invoked on the STA_IF
interface.
- The WIFI_EVENT_STA_START event is generated every time the STA_IF
interface is set active(True) and it was previously inactive, ie. not
only after calling esp_wifi_start().
- Also wait for WIFI_EVENT_STA_STOP when deactivating the interface.
- Also wait for relevant AP events.
Fixes issue #11910.
Signed-off-by: Glenn Moloney <glenn.moloney@gmail.com>
Signed-off-by: Damien George <damien@micropython.org>
Enabling mDNS put this firmware over the limit of the OTA partition size,
so tweak the compiler settings to reduce the firmware size.
Signed-off-by: Damien George <damien@micropython.org>
IDF v5.0 provides access to rssi value for received espnow packets via
recv_info arg to recv_cb().
Signed-off-by: Glenn Moloney <glenn.moloney@gmail.com>
This commit updates the esp32 port to work exclusively with ESP-IDF v5.
IDF v5 is needed for some of the newer ESP32 SoCs to work, and it also
cleans up a lot of the inconsistencies between existing SoCs (eg S2, S3,
and C3).
Support for IDF v4 is dropped because it's a lot of effort to maintain both
versions at the same time.
The following components have been verified to work on the various SoCs:
ESP32 ESP32-S2 ESP32-S3 ESP32-C3
build pass pass pass pass
SPIRAM pass pass pass N/A
REPL (UART) pass pass pass pass
REPL (USB) N/A pass pass N/A
filesystem pass pass pass pass
GPIO pass pass pass pass
SPI pass pass pass pass
I2C pass pass pass pass
PWM pass pass pass pass
ADC pass pass pass pass
WiFi STA pass pass pass pass
WiFi AP pass pass pass pass
BLE pass N/A pass pass
ETH pass -- -- --
PPP pass pass pass --
sockets pass pass pass pass
SSL pass ENOMEM pass pass
RMT pass pass pass pass
NeoPixel pass pass pass pass
I2S pass pass pass N/A
ESPNow pass pass pass pass
ULP-FSM pass pass pass N/A
SDCard pass N/A N/A pass
WDT pass pass pass pass
Signed-off-by: Damien George <damien@micropython.org>
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This function was made private/static in IDF commit
c67f4c2b4c2bb4b7740f988fc0f8a3e911e56afe, so it add back here.
Signed-off-by: Damien George <damien@micropython.org>
Mostly updates comments, but also renames the UASYNCIO enum value to
ASYNCIO.
This work was funded through GitHub Sponsors.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
The asyncio module now has much better CPython compatibility and
deserves to be just called "asyncio".
This will avoid people having to write `from uasyncio import asyncio`.
Renames all files, and updates port manifests to use the new path. Also
renames the built-in _uasyncio to _asyncio.
This work was funded through GitHub Sponsors.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Commit c046b23ea2 prevented frozen boot code
from being interrupted by Ctrl-C, but that means a corrupt filesystem will
forever lock up an esp32/esp8266 board. This commit fixes that by
explicitly enabling Ctrl-C before running the forever loop.
Signed-off-by: Damien George <damien@micropython.org>
This change enables the ULP (FSM) for all ESP32 variants rather than
requiring it to be enabled for each board specifically.
It also ensures the correct header file is included for each variant.
Lastly, it updates the IDF version we're builing against to v4.4.2, as that
version contains important fixes to make the ULP actually work on S2/S3
chips. See: https://github.com/espressif/esp-idf/commit/a0e3d48
Signed-off-by: Wilko Nienhaus <wilko.nienhaus@gmail.com>
This migrates the CMake variable `MICROPY_PORT_DIR` from the ESP-IDF
defined project to the component. Previously used instances of the variable
within the project definition have been migrated to
`CMAKE_CURRENT_LIST_DIR`. Within the component (the `main` subdirectory in
the ESP32 port) we define `MICROPY_PORT_DIR` using `CMAKE_CURRENT_LIST_DIR`
and subsequently use the `MICROPY_PORT_DIR` value in all locations where
`PROJECT` had previously been used.
Context:
In commit 9b90882146, initial support was added for building with the newly
introduced CMake support provided by the ESP-IDF.
Specifically, the commit message states:
> This commit adds support for building the esp32 port with CMake, and in
particular, it builds MicroPython as a component within the ESP-IDF. Using
CMake and the ESP-IDF build infrastructure makes it much easier to maintain
the port, especially with the various new ESP32 MCUs and their required
toolchains.
`PROJECT_DIR` is a variable populated by the ESP-IDF specifically and is
not stable when used with "[Pure CMake components][1]" as documented in the
ESP-IDF. It is intended to be used in the scope of the parent of the
current file (the "project") as opposed to the current file ("the
component"). Crossing into the parent scope like this works solely when the
"project" is MicroPython, but not when used as a component by other ESP-IDF
projects.
Analyzing this file, the intention is to reference the "Project" which in
the example is the parent directory. Within the [CMake variables][2]
documentation, there is one specifically defined for referencing the
directory for the CMake listfile currently being processed:
[`CMAKE_CURRENT_LIST_DIR`][3].
After making the change from `PROJECT_DIR` to `CMAKE_CURRENT_LIST_DIR`, the
reach into the parent scope defined by the ESP-IDF and the resulting CMake
interface violation is removed.
Similar to the component definition, the project `CMakeLists.txt` uses the
variable `CMAKE_SOURCE_DIR` which CMake defines as "The path to the top
level of the source tree." This commit changes the variable to
`CMAKE_CURRENT_LIST_DIR` for the reasons cited above.
[1]: https://docs.espressif.com/projects/esp-idf/en/latest/esp32s2/api-guides/build-system.html#writing-pure-cmake-components
[2]: https://cmake.org/cmake/help/latest/manual/cmake-variables.7.html
[3]: https://cmake.org/cmake/help/latest/variable/CMAKE_CURRENT_LIST_DIR.html
Signed-off-by: Brian 'redbeard' Harrington <redbeard@dead-city.org>
Following how mkrules.cmake works. This makes it easy for a port to enable
frozen code, by defining FROZEN_MANIFEST in its Makefile.
Signed-off-by: Damien George <damien@micropython.org>
This is a MicroPython-specific module that existed to support the old
version of uasyncio. It's undocumented and not enabled on all ports and
takes up code size unnecessarily.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Applies to drivers/examples/extmod/port-modules/tools.
This work was funded through GitHub Sponsors.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Updates any includes, and references from Makefiles/CMake.
This essentially reverts what was done long ago in commit
136b5cbd76
This work was funded through GitHub Sponsors.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This renames the builtin-modules, such that help('modules') and printing
the module object will show "module" rather than "umodule".
This work was funded through GitHub Sponsors.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Updates all `help()` output to use the phrase:
`For online docs please visit http://docs.micropython.org/`
Some ports previously used different wording, some pointed to the wrong
link. Also make all ports use `help.c` for consistency.
This work was funded through GitHub Sponsors.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
These have by default FAT support. The SAMD21 build does not support FAT.
The nrf port also implements os.sync(), but has it's own copy of moduos.c.
Code size increases seen: 40 to 56 bytes.
Signed-off-by: robert-hh <robert@hammelrath.com>
Change UART clock source on S3/C3 so the UART can operate when CPU
frequency is below 80MHz. This allows the UART to remain operational when
using Dynamic Frequency Scaling (DFS).
Signed-off-by: Patrick Joy <patrick@joytech.com.au>
This commit enables the ULP for the S2 and S3 chips.
Note this is the FSM (Finite State Machine) ULP.
Signed-off-by: Patrick Joy <patrick@joytech.com.au>
When the network module was first introduced in the esp8266 port in
ee3fec3167 there was only one interface (STA)
and, to save flash, the WLAN object was aliased to the network module,
which had just static methods for WLAN operations. This was subsequently
changed in 9e8396accb when the AP interface
was introduced, and the WLAN object became a true class.
But, network.WLAN remained a function that returned either the STA or AP
object and was never upgraded to the type itself. This scheme was then
copied over to the esp32 port when it was first introduced.
This commit changes network.WLAN from a function to a reference to the WLAN
type. This makes it consistent with other ports and network objects, and
allows accessing constants of network.WLAN without creating an instance.
Signed-off-by: Damien George <damien@micropython.org>
For esp32 and esp8266 this commit adds:
- a 'pm' option to WLAN.config() to set/get the wifi power saving mode; and
- PM_NONE, PM_PERFORMANCE and PM_POWERSAVE constants to the WLAN class.
This API should be general enough to use with all WLAN drivers.
Documentation is also added.
All ports that enable MICROPY_PY_MACHINE_PWM now enable these two
sub-options, so remove these sub-options altogether to force consistency in
new ports that implement machine.PWM.
Signed-off-by: Damien George <damien@micropython.org>
ESP-NOW is a proprietary wireless communication protocol which supports
connectionless communication between ESP32 and ESP8266 devices, using
vendor specific WiFi frames. This commit adds support for this protocol
through a new `espnow` module.
This commit builds on original work done by @nickzoic, @shawwwn and with
contributions from @zoland. Features include:
- Use of (extended) ring buffers in py/ringbuf.[ch] for robust IO.
- Signal strength (RSSI) monitoring.
- Core support in `_espnow` C module, extended by `espnow.py` module.
- Asyncio support via `aioespnow.py` module (separate to this commit).
- Docs provided at `docs/library/espnow.rst`.
Methods available in espnow.ESPNow class are:
- active(True/False)
- config(): set rx buffer size, read timeout and tx rate
- recv()/irecv()/recvinto() to read incoming messages from peers
- send() to send messages to peer devices
- any() to test if a message is ready to read
- irq() to set callback for received messages
- stats() returns transfer stats:
(tx_pkts, tx_pkt_responses, tx_failures, rx_pkts, lost_rx_pkts)
- add_peer(mac, ...) registers a peer before sending messages
- get_peer(mac) returns peer info: (mac, lmk, channel, ifidx, encrypt)
- mod_peer(mac, ...) changes peer info parameters
- get_peers() returns all peer info tuples
- peers_table supports RSSI signal monitoring for received messages:
{peer1: [rssi, time_ms], peer2: [rssi, time_ms], ...}
ESP8266 is a pared down version of the ESP32 ESPNow support due to code
size restrictions and differences in the low-level API. See docs for
details.
Also included is a test suite in tests/multi_espnow. This tests basic
espnow data transfer, multiple transfers, various message sizes, encrypted
messages (pmk and lmk), and asyncio support.
Initial work is from https://github.com/micropython/micropython/pull/4115.
Initial import of code is from:
https://github.com/nickzoic/micropython/tree/espnow-4115.
This allows updating mp_mbedtls_errors.c for the other mbedtls based ports
based on mbedTLS v2.28.1. This esp32-specific file will not be required
after updating IDF support to >= v4.4.1.
Signed-off-by: Carlos Gil <carlosgilglez@gmail.com>
Based on extmod/utime_mphal.c, with:
- a globals dict added
- time.localtime wrapper added
- time.time wrapper added
- time.time_ns function added
New configuration options are added for this module:
- MICROPY_PY_UTIME (enabled at basic features level)
- MICROPY_PY_UTIME_GMTIME_LOCALTIME_MKTIME
- MICROPY_PY_UTIME_TIME_TIME_NS
Signed-off-by: Damien George <damien@micropython.org>
The previous code worked on ESP32 but not ESP32-S3. All the IDF (v4.4.3)
examples call rmt_set_tx_loop_mode before rmt_write_items, so make that
change here.
Signed-off-by: Damien George <damien@micropython.org>
This commit adds support for the `timeout` keyword argument to machine.I2C
on the rp2 port, following how it's done on other ports.
The main motivation here is avoid the interpreter crashing due to infinite
loops when SDA is stuck low, which is quite common if the board gets reset
while reading from an I2C device.
A default timeout of 50ms is chosen because it's consistent with:
- Commit a707fe50b0 which used a timeout of
50,000us for zero-length writes on the rp2 port.
- The machine.SoftI2C class which uses 50,000us as the default timeout.
- The stm32 port's hardware I2C, which uses 50,000us for
I2C_POLL_DEFAULT_TIMEOUT_US.
This commit also fixes the default timeout on the esp32 port to be
consistent with the above, and updates the documentation for machine.I2C to
document this keyword argument.
Helps prevent the filesystem from getting formatted by mistake, among other
things. For example, on a Pico board, entering Ctrl+D and Ctrl+C fast many
times will eventually wipe the filesystem (without warning or notice).
Further rationale: Ctrl+C is used a lot by automation scripts (eg mpremote)
and UI's (eg Mu, Thonny) to get the board into a known state. If the board
is not responding for a short time then it's not possible to know if it's
just a slow start up (eg in _boot.py), or an infinite loop in the main
application. The former should not be interrupted, but the latter should.
The only way to distinguish these two cases would be to wait "long enough",
and if there's nothing on the serial after "long enough" then assume it's
running the application and Ctrl+C should break out of it. But defining
"long enough" is impossible for all the different boards and their possible
behaviour. The solution in this commit is to make it so that frozen
start-up code cannot be interrupted by Ctrl+C. That code then effectively
acts like normal C start-up code, which also cannot be interrupted.
Note: on the stm32 port this was never seen as an issue because all
start-up code is in C. But now other ports start to put more things in
_boot.py and so this problem crops up.
Signed-off-by: David Grayson <davidegrayson@gmail.com>
This is a best-effort implementation of write polling. It's difficult to
do correctly because if there are multiple output streams (eg UART and USB
CDC) then some may not be writeable while others are. A full solution
should also have a return value from mp_hal_stdout_tx_strn(), returning the
number of bytes written to the stream(s). That's also hard to define.
The renesas-ra and stm32 ports already implement a similar best-effort
mechanism for write polling.
Fixes issue #11026.
Signed-off-by: Damien George <damien@micropython.org>
Rather than duplicating the implementation of `network`, this allows ESP32
to use the shared one in extmod. In particular this gains access to
network.hostname and network.country.
Set default hostnames for various ESP32 boards.
Other than adding these two methods and the change to the default hostname,
there is no other user-visible change.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This matches the behavior of the makefile ports but implemented for CMake,
making it easy to specify custom board definitions.
This work was funded through GitHub Sponsors.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This will ensure that any board with networking support gets:
- webrepl
- mip
- urequests
- ntptime
This work was funded through GitHub Sponsors.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
The delay is 1 ms. It avoids the crashes reported by the
issues #8289, #8792 and #9236 with esp-idf versions >= 4.2, but does
not solve an underlying problem in the esp-idf.
The major setting is about the PHY interface configuration. The
configuration matches the Olimex ESP32 Gateway as well.
Tested with esp-idf v4.2.4 and Olimex ESP32 POE boards.
`esp_eth_ioctl(ETH_CMD_S_MAC_ADDR)` sets the MAC address of the hardware
device, but we also need to notify the upper layers of the change so that
e.g. DHCP work properly.
Add support for various SPI-based ethernet chips (W5500, KSZ8851SNL,
DM9051) to the ESP32 port. This leverages the existing support in ESP-IDF
for these chips -- which configures these chips in "MAC raw" mode -- and
the existing support for network.LAN in the ESP32 port. In particular,
this doesn't leverage the wiznet5k support that is used on the rp2 and
stm32 ports (because that's for native use of lwIP).
Tested on the POE Featherwing (with the SJIRQ solder jumper bridged) and a
ESP32-S3 feather.
A note about the interrupt pin: The W5500 implementation within ESP-IDF
relies on hardware interrupt, and requires the interrupt pin from the W5500
to be wired to a GPIO. This is not the case by default on the Adafruit
Ethernet FeatherWing, which makes it not directly compatible with this
implementation.
Both the direction and the Pin used for ref_clk can now be configured. It
Requires at least idf v4.4. The new keyword arguments to the constructor
are:
- ref_clk_mode=mode: with mode being Pin.IN or Pin.OUT. If it is not set,
then the default configuration is used, which may be configured by
kconfig settings.
- ref_clk=pin_obj: which defines the Pin used for ref_clk. This is either
Pin(0), Pin(16) or Pin(17). No check is done for the pin number. If it
is the wrong one, it simply will not work. Besides that, no harm.
LAN8710 uses the same drivers as LAN8720, so this commit just adds the
names. Alternatively, both could be summarised under LAN87xx, like the
esp-idf does.
This was introduced by 35fb90bd57, but
it is much simpler and essentially the same to just use
`tud_cdc_n_connected()`.
The only difference is that tud_cdc_n_connected() only checks for DTR,
but this is correct anyway: DTR indicates device presence, RTS indicates
that the host wants to receive data.
Signed-off-by: Damien Tournoud <damien@platform.sh>
usocket_events_deinit will only be available if MICROPY_PY_USOCKET_EVENTS
is enabled (which is only enabled when webrepl is enabled).
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
The original ESP32 only supports timer source clock APB so it doesn't need
and doesn't have a clk_src field.
The ESP32C3 supports timer source clock APB and XTAL so it does have a
clk_src field, and this needs to be configured to get the correct period.
Fixes#8084.
Follow up to 8a91c719 to no longer explicitly disable BLE in
mpconfigport.h.
This work was funded through GitHub Sponsors.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Instead of defining `MICROPY_PY_BTREE` in `mpconfigport.h` we can define
it via CMake similar to how other ports that use Makefiles define it in
`mpconfigport.mk`.
Signed-off-by: David Lechner <david@pybricks.com>
If USB CDC is connected and the board sends data, but the host does not
receive the data, the device locks up. This is fixed in this commit by
having a timeout of 500ms, after which time the transmission is skipped.
Checks are added for pwm.freq(), pwm_duty(), pwm_duty_u10() and
pwm.duty_u16(). This avoids a core dump on ESP32C3, and misleading error
messages on Xtensa ESP32 devices.
Set the size of machine_pin_irq_handler array to GPIO_NUM_MAX:
- Min GPIO_NUM_MAX is 22 for IDF_TARGET_ESP32C3.
- Max GPIO_NUM_MAX is 49 for IDF_TARGET_ESP32S3.
The MP_REGISTER_ROOT_POINTER entry must be hard-coded, because the location
that it's evaluated by the compiler does not include the relevant IDF
header to get a definition of GPIO_NUM_MAX.
Each SoC family has its own clocks and timings/timeouts. For I2C, the
default source clock is either APB (ESP32, ESP32-S2) or XTAL (ESP32-S3,
ESP32-C3) as shown in the datasheets. Since
machine_i2c.c/machine_hw_i2c_init() uses the default clk_flags (0), the
alternate low-power clock source is never selected in ESP-IDF
i2c.c/i2c_param_config(). There is not an API in i2c.c to get the source
clock frequency, so a compile-time value is used based on SoC family.
Also, the maximum timeout is different across the SoC families, so use the
I2C_LL_MAX_TIMEOUT constant to eliminate the warning from
i2c_set_timeout().
With these changes, the following results were obtained. The I2C SCL
frequencies were measured with a Saleae logic analyzer.
ESP32 (TTGO T Dislay)
I2C(0, scl=22, sda=21, freq=101781) Measured: 100KHz
I2C(0, scl=22, sda=21, freq=430107) Measured: 400KHz
I2C(0, scl=22, sda=21, freq=1212121) Measured: 941KHz
ESP32-S3 (TTGO T-QT)
I2C(0, scl=34, sda=33, freq=111111) Measured: 107KHz
I2C(0, scl=34, sda=33, freq=444444) Measured: 400KHz
I2C(0, scl=34, sda=33, freq=1111111) Measured: 842KHz
ESP32-C3 (XIAO ESP32C3)
I2C(0, scl=7, sda=6, freq=107816) Measured: 103KHz
I2C(0, scl=7, sda=6, freq=444444) Measured: 380KHz
I2C(0, scl=7, sda=6, freq=1176470) Measured: 800KHz
(ESP32-S2 board was not available for testing.)
Auto DMA channel is supported in IDF v4.4, and is required to be used on S3
chips, so use this simpler configuration option where possible.
Fixes issue #8634.
Signed-off-by: Damien George <damien@micropython.org>
Updates all README.md and docs, and manifests to `require("mip")`.
Also extend and improve the documentation on freezing and packaging.
This work was funded through GitHub Sponsors.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Instead of being an explicit field, it's now a slot like all the other
methods.
This is a marginal code size improvement because most types have a make_new
(100/138 on PYBV11), however it improves consistency in how types are
declared, removing the special case for make_new.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
The goal here is to remove a slot (making way to turn make_new into a slot)
as well as reduce code size by the ~40 references to mp_identity_getiter
and mp_stream_unbuffered_iter.
This introduces two new type flags:
- MP_TYPE_FLAG_ITER_IS_ITERNEXT: This means that the "iter" slot in the
type is "iternext", and should use the identity getiter.
- MP_TYPE_FLAG_ITER_IS_CUSTOM: This means that the "iter" slot is a pointer
to a mp_getiter_iternext_custom_t instance, which then defines both
getiter and iternext.
And a third flag that is the OR of both, MP_TYPE_FLAG_ITER_IS_STREAM: This
means that the type should use the identity getiter, and
mp_stream_unbuffered_iter as iternext.
Finally, MP_TYPE_FLAG_ITER_IS_GETITER is defined as a no-op flag to give
the default case where "iter" is "getiter".
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Changes in this commit:
- Manifest include's now use the directory path where possible (no longer
necessary to include the manifest.py file explicitly).
- Add manifest.py for all drivers and components that are referenced by
port/board manifests.
- Replace all uses of freeze() with package()/module(), except for port and
board modules.
- Use opt=3 everywhere, for consistency and to reduce code size.
- Use require() instead of include() for all micropython-lib references.
- Remove support for optional board-level manifest.py in mimxrt port, to
make it behave the same as other ports (the board must set
FROZEN_MANIFEST to a custom manifest.py, which can optionally include the
default, port-level manifest).
- Also reinstates modules that were accidentally removed from the esp8266
512k build in fbe9417b90.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
Signed-off-by: Damien George <damien@micropython.org>
uart.flush()
flush() will wait until all characters have been sent.To
avoid a permanent lock, a timeout applies depending on the
size of txbuf and the baud rate.
ret = uart.txdone()
ret is True if no transfer is in progress.
ret is False otherwise.
So that everything is reset and the SD card can be created again after
calling SDCard.deinit() (and after a soft reset).
Fixes issue #8949.
Signed-off-by: Damien George <damien@micropython.org>
Having two separate manifests is confusing. It's simpler to have the daily
builds use the same configuration as the stable, release builds.
Signed-off-by: Damien George <damien@micropython.org>
Previously the desired output type was specified. Now make the type part
of the function name. Because this function is used in a few places this
saves code size due to smaller call-site.
This makes `mp_obj_new_str_type_from_vstr` a private function of objstr.c
(which is almost the only place where the output type isn't a compile-time
constant).
This saves ~140 bytes on PYBV11.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
It used to be 10 bit times, which is too short. The break state must be
longer than a regular character time, at least 13 bit times. This is now
implemented by reducing the baudrate while sending the "0". The break time
will now vary with data length and parity setting, but will at least be 15
bit times.
Tested with a GENERIC_SPIRAM, GENERIC_C3 and UM_TINYS2 board.