Commit Graph

26 Commits

Author SHA1 Message Date
Patrick Van Oosterwijck a66bd7a489 esp32/boards: Add GENERIC_C3_USB board with USB serial/JTAG support.
Add a new board type for ESP32-C3 revision 3 and up that implement the USB
serial/JTAG port on pin 18 and 19.  This variant uses the USB serial for
programming and console, leaving the UART free.

- Pins 18 and 19 are correctly reserved for this variant.  Also pins 14-17
  are reserved for flash for any ESP32-C3 so they can't be reconfigured
  anymore to crash the system.
- Added usb_serial_jtag.c and .h to implement this interface.
- Interface was tested to work correctly together with webrepl.
- Interface was tested to work correctly when sending and receiving
  large files with ampy.
- Disconnecting terminal or USB will not hang the system when it's
  trying to print.
2021-08-31 00:12:41 +10:00
Damien George 6214fa3f9e esp32/mphalport: Always yield at least once in delay_ms.
This helps the OS switch to and give other threads processing time during
the sleep.  It also ensures that pending events are handled, even when
sleeping for 0ms.

Fixes issue #5344.

Signed-off-by: Damien George <damien@micropython.org>
2021-07-22 00:20:53 +10:00
Damien George 6823514845 esp32: Add initial support for ESP32C3 SoCs.
Supported features for this SoC are:
- UART REPL, filesystem
- Pin, ADC, PWM, SoftI2C, SoftSPI, Timer, RTC
- OneWire, DHT, NeoPixel
- RMT
- WiFi, Bluetooth

Signed-off-by: Damien George <damien@micropython.org>
2021-07-18 23:58:24 +10:00
Damien George 59dbbe9be7 esp32: Fix use of mp_int_t, size_t and uintptr_t.
Signed-off-by: Damien George <damien@micropython.org>
2021-07-18 23:58:16 +10:00
Damien George 136369d72f all: Update to point to files in new shared/ directory.
Signed-off-by: Damien George <damien@micropython.org>
2021-07-12 17:08:10 +10:00
Damien George 132d93886f ports: Use common mp_hal_stdout_tx_strn_cooked instead of custom one.
To reduce code duplication.

Signed-off-by: Damien George <damien@micropython.org>
2021-07-08 12:59:31 +10:00
Damien George 5093d49fae esp32: Extend support for S2 series, and S3 where applicable.
Improvements made:
- PSRAM support for S2
- partition definition for 16MiB flash
- correct ADC and DAC pins
- correct GPIO and IRQ pins
- S3 components in CMakeLists

Based on original commit made by Seon Rozenblum aka @UnexpectedMaker.

Signed-off-by: Damien George <damien@micropython.org>
2021-05-10 16:56:53 +10:00
Damien George c81d048bb3 esp32: Add support for USB with CDC ACM.
The REPL will be available on the USB serial port.

Signed-off-by: Damien George <damien@micropython.org>
2021-04-15 10:31:06 +10:00
Damien George f12462ddc4 esp32: Remove obsolete IDF v3 code wrapped in MICROPY_ESP_IDF_4.
Signed-off-by: Damien George <damien@micropython.org>
2021-02-15 23:22:05 +11:00
Damien George 97072b7224 esp32: Add explicit initialisers to silence compiler warnings.
This makes no functional change.  See similar commit
9aa58cf8ba

Signed-off-by: Damien George <damien@micropython.org>
2021-02-15 16:37:58 +11:00
Damien George 8f20cdc353 all: Rename absolute time-based functions to include "epoch".
For time-based functions that work with absolute time there is the need for
an Epoch, to set the zero-point at which the absolute time starts counting.
Such functions include time.time() and filesystem stat return values.  And
different ports may use a different Epoch.

To make it clearer what functions use the Epoch (whatever it may be), and
make the ports more consistent with their use of the Epoch, this commit
renames all Epoch related functions to include the word "epoch" in their
name (and remove references to "2000").

Along with this rename, the following things have changed:

- mp_hal_time_ns() is now specified to return the number of nanoseconds
  since the Epoch, rather than since 1970 (but since this is an internal
  function it doesn't change anything for the user).

- littlefs timestamps on the esp8266 have been fixed (they were previously
  off by 30 years in nanoseconds).

Otherwise, there is no functional change made by this commit.

Signed-off-by: Damien George <damien@micropython.org>
2020-09-18 17:20:34 +10:00
Damien George 40153b800a esp32/mphalport: Fix mp_hal_time_ns offset.
gettimeofday returns seconds since 2000/1/1 so needs to be adjusted to
seconds since 1970/1/1 to give the correct return value of mp_hal_time_ns.

Signed-off-by: Damien George <damien@micropython.org>
2020-08-31 00:49:58 +10:00
Damien George ee50a6effe py/mphal.h: Introduce mp_hal_time_ns and implement on various ports.
This should return a 64-bit value being the number of nanoseconds since
1970/1/1.

Signed-off-by: Damien George <damien@micropython.org>
2020-08-22 16:13:44 +10:00
Damien George e08ca78f40 py/stream: Remove mp_stream_errno and use system errno instead.
This change is made for two reasons:

1. A 3rd-party library (eg berkeley-db-1.xx, axtls) may use the system
   provided errno for certain errors, and yet MicroPython stream objects
   that it calls will be using the internal mp_stream_errno.  So if the
   library returns an error it is not known whether the corresponding errno
   code is stored in the system errno or mp_stream_errno.  Using the system
   errno in all cases (eg in the mp_stream_posix_XXX wrappers) fixes this
   ambiguity.

2. For systems that have threading the system-provided errno should always
   be used because the errno value is thread-local.

For systems that do not have an errno, the new lib/embed/__errno.c file is
provided.
2020-04-27 23:58:46 +10:00
Thorsten von Eicken 1ae7e0e561 esp32: Consolidate check_esp_err functions and add IDF error string.
This commit consolidates a number of check_esp_err functions that check
whether an ESP-IDF return code is OK and raises an exception if not.  The
exception raised is an OSError with the error code as the first argument
(negative if it's ESP-IDF specific) and the ESP-IDF error string as the
second argument.

This commit also fixes esp32.Partition.set_boot to use check_esp_err, and
uses that function for a unit test.
2020-04-23 10:59:07 +10:00
Damien George 98a3911c43 py/scheduler: Add "raise_exc" argument to mp_handle_pending.
Previous behaviour is when this argument is set to "true", in which case
the function will raise any pending exception.  Setting it to "false" will
cancel any pending exception.
2020-02-07 16:08:20 +11:00
Jim Mussared 96008ff59a esp32: Support building with ESP IDF 4.0-beta1.
This commit adds support for a second supported hash (currently set to the
4.0-beta1 tag).  When this hash is detected, the relevant changes are
applied.

This allows to start using v4 features (e.g. BLE with Nimble), and also
start doing testing, while still supporting the original, stable, v3.3 IDF.

Note: this feature is experimental, not well tested, and network.LAN and
network.PPP are currently unsupported.
2019-09-17 12:25:36 +10:00
Damien George c80614dfc8 ports: Provide mp_hal_stdio_poll for sys.stdio polling where needed. 2019-07-01 17:10:12 +10:00
Damien George 297092a76a esp32/mphalport: Use ets_delay_us for mp_hal_delay_us_fast.
The system provided one is in ROM and is more accurate.
2019-03-12 15:46:44 +11:00
Damien George efe0569c26 esp32/mphalport: When tx'ing to REPL only release GIL if many chars sent
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.
2019-01-10 15:43:47 +11:00
Nicko van Someren 14ab81e87a esp32: Reduce latency for handling of scheduled Python callbacks.
Prior to this patch there was a large latency for executing scheduled
callbacks when when Python code is sleeping: at the heart of the
implementation of sleep_ms() is a call to vTaskDelay(1), which always
sleeps for one 100Hz tick, before performing another call to
MICROPY_EVENT_POLL_HOOK.

This patch fixes this issue by using FreeRTOS Task Notifications to signal
the main thread that a new callback is pending.
2018-07-04 10:49:37 +10:00
Damien George 98b05e3614 esp32: Add support for and enable uos.dupterm(). 2018-04-27 23:51:45 +10:00
Damien George 04dc4a5034 esp32/mphalport: Improve mp_hal_stdout_tx_XXX functions.
This makes way for enabling uos.dupterm().
2018-04-27 23:49:21 +10:00
Damien George 4ed5865280 esp32/mphalport: Improve mp_hal_delay_us so it handles pending events.
Thanks to @bboser for the initial idea and implementation.
2018-04-26 20:21:33 +10:00
Damien George e1fe3abd09 esp32/mphalport: Use esp_timer_get_time instead of gettimeofday.
It's more efficient and improves accuracy.
2018-04-26 20:19:31 +10:00
Damien George bc08c884a2 esp32: Add new port to Espressif ESP32 SoC.
This commit is a combination of 216 commits from the initial stages of
development of this port, up to and including the point where the code was
moved to the ports/esp32 directory.  These commits were mostly concerned
with setting up the build system and getting a reliable port working with
basic features.  The following is a digest of the original commits in their
original order (most recent listed first), grouped where possible per
author.  The list is here to give credit for the work and provide some
level of traceability and accountability.  For the full history of
development please consult the original repository.

All code is MIT licensed and the relevant copyright holders are listed in
the comment-header of each file.

Damien George <damien.p.george@gmail.com>
  esp32: Update to latest ESP IDF.
  esp32: Update module symlinks now that code lives under the ports dir.
  esp32: Update to compile with new ports/esp32 directory structure.
  esp32: Move it to the ports/ directory.
  esp32/machine_uart: Don't save baudrate but compute it instead.
  esp32/modsocket: Add socket.readinto() method.
  esp32/modesp: Add esp.gpio_matrix_in and esp.gpio_matrix_out functions.
  esp32/machine_uart: Wait for all data to be tx'd before changing config.

NyxCode <moritz.bischof1@gmail.com>
  esp32: Add note to README.md about updating the submodules of ESP IDF.

Anthony Briggs <anthony.briggs@gmail.com>
  esp32: Update README.md installation and flashing instructions.

Javier Candeira <javier@candeira.com>
  esp32: Raise error when setting input-only pin to output.

  With help from Adrian Smith (fon@thefon.net)

Javier Candeira <javier@candeira.com>
  esp32: Replace exception raising with corresponding mp_raise_XXX funcs.

Tisham Dhar <whatnickd@gmail.com>
  esp32: Add some specific notes about building on Windows using WSL.

Ben Gamari <ben@smart-cactus.org>
  esp32: Provide machine.Signal class.

Damien George <damien.p.george@gmail.com>
  esp32/modnetwork: Implement AP version of network.isconnected().

Eric Poulsen <eric@zyxod.com>
  esp32/README.md: Add note about btree submodule initialization.

Damien George <damien.p.george@gmail.com>
  esp32: Make firmware.bin start at 0x1000 to allow flash size autodetect.
  esp32: Changes to follow latest version of upstream uPy.
  esp32/Makefile: Separate ESP-specific inc dirs to avoid header clashes.
  esp32: Enable "btree" database module.
  esp32: Update to latest ESP IDF.

Roosted7 <thomasroos@live.nl>
  esp32: Update to latest ESP-IDF.

Alex King <alex_w_king@yahoo.com>
  esp32/machine_timer: Add support for esp32 hardware timer.

  Code lineage:
  Timer() is based loosely on the version in esp8266, although the
  implementation is differs significantly because of the change in
  the underlying platform.

Damien George <damien.p.george@gmail.com>
  esp32/machine_uart: Increase UART TX buffer size to 64.
  esp32/modules: Update dht symlink.
  esp32/mpconfigport.h: Enable utimeq module, needed for uasyncio.
  esp32: Changes to follow latest version of upstream uPy.
  esp32: Update to latest ESP-IDF.
  esp32/machine_uart: Add uart.any() method.
  esp32/machine_uart: Uninstall the UART driver before installing it.

Thomas Roos <mail@thomasroos.nl>
  esp32: Update to latest ESP-IDF.

Eric Poulsen <eric@zyxod.com>
  esp32/modsocket: Make read/write return None when in non-blocking mode.
  esp32/modsocket.c: Fix send/sendto/write for non-blocking sockets.

Odd Stråbø <oddstr13@openshell.no>
  esp32: Initial working implementation of machine.UART.

  Code lineage (as seen by previous commits): I copied the ESP8266 code,
  renamed pyb -> machine, and used esp-idf as a reference while implementing
  minimal functionality.  I provide all of my changes under the MIT license.

Odd Stråbø <oddstr13@openshell.no>
  esp32/machine_uart: Rename pyb to machine.
  esp32: Copy machine_uart.c from esp8266 port.

Damien George <damien.p.george@gmail.com>
  esp32/moduos: Add uos.ilistdir() function.
  esp32: Mount filesystem at the root of the VFS, following esp8266.

Andy Valencia <vandyswa@gmail.com>
  esp32: Add hardware SHA1/SHA256 support via mbedtls API.

  Code lineage: a copy of extmod/moduhashlib with the API invocation details
  edited.  Total derivative work.

Andy Valencia <vandyswa@gmail.com>
  esp32: Add PWM support via machine.PWM class.

  Code lineage:
  I started by copying the esp8266 machine_pwm.c. I used information from the
  ESP32 Technical Reference Manual, the esp-idf documentation, and the SDK's
  sample ledc example code (but I did not copy that code, just studied it to
  understand the SDK's API for PWM). So aside from the code copied from the
  esp8266 PWM support, everything else you see is just new code I wrote.

  I wasn't an employee of anybody when I wrote it, and I wrote it with the
  understanding and intention that it's simply a derivative work of the
  existing micropython code. I freely and willingly contribute it to the
  project and intend that it not change the legal status of the micropython
  code base in any way, even if it is included in that base in whole or part.

Damien George <damien.p.george@gmail.com>
  esp32/modules: Add symlinks for upysh and upip.

Eric Poulsen <eric@zyxod.com>
  esp32/modmachine: Add unique_id() function to machine module.

Damien George <damien.p.george@gmail.com>
  esp32: Change dac_out_voltage to dac_output_voltage for new IDF API.
  esp32: Update esp32.custom_common.ld to align with changes in ESP IDF.

Eric Poulsen <eric@zyxod.com>
  esp32: Update to latest ESP IDF.

Damien George <damien.p.george@gmail.com>
  esp32/modsocket: When resolving IP addr handle the case of host=''.
  esp32: Update to latest ESP IDF.

Eric Poulsen <eric@zyxod.com>
  esp32/Makefile: Change default FLASH_MODE to dio for WROOM-32 module.
  esp32: Move FAT FS to start at 0x200000 and increase size to 2MiB.

Damien George <damien.p.george@gmail.com>
  esp32: Remove enable_irq/disable_irq and use ATOMIC_SECTION instead.
  esp32/mpconfigport.h: Provide ATOMIC_SECTION macros.
  esp32/main: Restart the MCU if there is a failed NLR jump.

Daniel Campora <daniel@pycom.io>
  esp32: Enable threading; be sure to exit GIL when a thread will block.
  esp32: Trace the registers when doing a gc collect. Also make it thread ready.
  esp32: Add threading implementation, disabled for the time being.

Damien George <damien.p.george@gmail.com>
  esp32: Update to latest ESP IDF.
  esp32/uart: Use high-level function to install UART0 RX ISR handler.
  esp32/Makefile: Make FreeRTOS private include dir really private.

Eric Poulsen <eric@zyxod.com>
  esp32: Add support for hardware SPI peripheral (block 1 and 2).

Sergio Conde Gómez <skgsergio@gmail.com>
  esp32/modules/inisetup.py: Mount filesystem at /flash like ESP8266

Damien George <damien.p.george@gmail.com>
  esp32: Convert to use core-provided KeyboardInterrupt exception.
  esp32: Pump the event loop while waiting for rx-chr or delay_ms.
  esp32: Implement Pin.irq() using "soft" scheduled interrupts.
  esp32: Update to latest ESP IDF version.

Eric Poulsen <eric@zyxod.com>
  esp32/README: Add troubleshooting section to the end.

tyggerjai <tyggerjai@gmail.com>
  esp32: Add support for WS2812 and APA106 RGB LEDs.

Damien George <damien.p.george@gmail.com>
  esp32: Add makeimg.py script to build full firmware; use it in Makefile.
  esp32/modsocket: Make socket.read return when socket closes.
  esp32/modsocket: Initialise the timeout on an accepted socket.
  esp32/mphalport: Provide proper implementations of disable_/enable_irq.
  esp32/modmachine: Add disable_irq/enable_irq functions.

Nick Moore <nick@zoic.org>
  esp32/modsocket.c: add comment explaining timeout behaviour
  esp32/modsocket.c: clean up send methods for retries too
  esp32/modsocket.c: sockets always nonblocking, accept timeout in modsocket
  esp32: Update to latest ESP IDF version.
  esp32/modsocket.c: remove MSG_PEEK workaround on select ioctl.
  esp32/modsocket.c: Initialize tcp when modsocket loads.

Damien George <damien.p.george@gmail.com>
  esp32/main: Bump heap size from 64k to 96k.
  esp32/modutime: Add time.time() function.
  esp32/modsocket: Convert lwip errnos to uPy ones.
  esp32/modules: Provide symlink to ds18x20 module.
  esp32: Add support for onewire protocol via OneWire module.
  esp32: Add support for DHT11 and DHT22 sensors.
  esp32/mphalport: Improve delay and ticks functions.
  esp32: Update to latest ESP IDF.
  esp32/modules: Provide symlink to urequests from micropython-lib.
  esp32: Populate sys.path.

Nick Moore <nick@zoic.org>
  esp32/machine_dac.c: implement DAC pins as well
  esp32/machine_adc.c: also machine.ADC
  esp32/machine_touchpad.c: add support for touchpad

Damien George <damien.p.george@gmail.com>
  esp32/README: Add hint about using GNUmakefile on case-insensitive FS.
  esp32/mpconfigport.h: Enable maximum speed software SPI.
  esp32: Provide improved version of mp_hal_delay_us_fast.
  esp32/mpconfigport.h: Enable MICROPY_PY_BUILTINS_POW3 option.
  esp32: Update to latest ESP IDF.
  esp32: Convert to use new oofatfs library and generic VFS sub-system.
  esp32: Enable help('modules') to list builtin modules.
  esp32: Convert to use new builtin help function.

Aaron Kelly <AaronKelly@email.com>
  esp32/README: Add comment about ESP-IDF version

Damien George <damien.p.george@gmail.com>
  esp32: Consistently use size_t instead of mp_uint_t.
  esp32: Change "Micro Python" to "MicroPython" in license comments.
  esp32/Makefile: Use -C argument to git instead of cd'ing.
  esp32/help: Add section to help about using the network module.
  esp32/README: Add section about configuring and using an ESP32 board.
  esp32/README: Remove paragraph about buggy toolchain, it's now fixed.
  esp32/modnetwork: Change network init logging from info to debug.
  esp32/modnetwork: Don't start AP automatically when init'ing wifi.
  esp32/modsocket: Implement socket.setsockopt, to support SO_REUSEADDR.
  esp32: Update to latest ESP IDF.
  esp32/sdkconfig.h: Remove unused CONFIG_ESPTOOLPY_xxx config settings.
  esp32/modsocket: Add support for DGRAM and RAW, and sendto/recvfrom.
  esp32/modsocket: Fix return value of "port" in socket.accept.
  esp32/modsocket: Make socket.recv take exactly 2 args.
  esp32: Enable ussl module, using mbedtls component from ESP IDF.
  esp32/modsocket: Rename "socket" module to "usocket".
  esp32/sdkconfig: Increase max number of open sockets from 4 to 8.
  esp32/modsocket: Add error checking for creating and closing sockets.
  esp32/modsocket: Use _r (re-entrant) versions of LWIP socket API funcs.
  esp32/modsocket: Raise an exception if socket.connect did not succeed.
  esp32/modsocket: Make socket.accept return a tuple: (client, addr).
  esp32/modsocket: Use m_new_obj_with_finaliser instead of calloc.
  esp32/Makefile: Add check for IDF version, and warn if not supported.
  esp32/esp32.custom_common.ld: Update to follow changes in IDF.
  esp32: Update to latest ESP IDF.

nubcore <x@nubcore.com>
  esp32: add #define CONFIG_ESP32_WIFI_RX_BUFFER_NUM 25

Nick Moore <nick@zoic.org>
  esp32/modsocket.c: add in sendall and makefile methods #10
  esp32/modsocket.c: fixups for #10
  esp32/modsocket.c: fix copyright, socket_recv gets param and exception
  esp32/modnetwork.c: fix copyright, network.active param to bool

Damien George <damien.p.george@gmail.com>
  esp32/modnetwork: Implement wlan.isconnected() method.
  esp32/modnetwork: Add initial implementation of wlan.config().
  esp32/modnetwork: Simplify event_handler messages.

Nick Moore <nick@zoic.org>
  esp32/modsocket.c: support for ioctl, settimeout, setblocking, getaddrinfo

Damien George <damien.p.george@gmail.com>
  esp32/README: Add comment about FLASH_MODE being dio.
  esp32: Update to latest ESP IDF.
  esp32/modnetwork: Remove unnecessary indirection variable for scan list.
  esp32/modnetwork: Check that STA is active before trying to scan.
  esp32/mphalport: Replace portTICK_RATE_MS with portTICK_PERIOD_MS.
  esp32/README: Add comment about using $(HOME) in makefile.
  esp32/modnetwork: Use memset instead of bzero, the latter is deprecated.
  esp32/modnetwork: Improve error handling when STA is connecting to AP.
  esp32/Makefile: Use tab instead of spaces, and use shorter variable.

Nick Moore <nick@zoic.org>
  esp32/modsocket.c: AF_*, SOCK_* and IPPROTO_* constants
  esp32/modsocket.c: socket.settimeout implementation

Damien George <damien.p.george@gmail.com>
  esp32/Makefile: Update to latest ESP IDF.

Nick Moore <nick@zoic.org>
  esp32/modsocket.c: use mp streams for sockets
  esp32: network.WLAN.ifconfig based on esp8266 version
  esp32: Fix up exception handling
  esp32: sketchy modsocket ... revisit this once modnetwork is sorted
  esp32: First cut at modnetwork, manually rebased from prev. version

Damien George <damien.p.george@gmail.com>
  esp32/help: Update help text.
  esp32: Add info about Microbric Pty Ltd being the sponsor of this port.
  esp32: Add README.md file.
  esp32/mpconfigport.h: Add weak links to many of the builtin modules.
  esp32: Enable soft implementation of machine.SPI class.
  esp32/Makefile: Simplify APP_LD_ARGS by using OBJ variable.
  esp32/Makefile: Reorganise Makefile and add some comments.
  esp32/Makefile: Clean up CFLAGS for ESP IDF components.
  esp32/Makefile: Tidy up names of ESP IDF components, to match dir name.
  esp32/Makefile: Define and use ESPCOMP variable.
  esp32: Update to latest ESP IDF.
  esp32/main: Enable filesystem support.
  esp32: Use custom ld script to ensure correct code get placed in iram.
  esp32: Update to latest ESP IDF.
  esp32/main: Pin the uPy task to core 0.
  esp32: Update to use latest ESP IDF.
  esp32: Disable boot-up scripts, spi_flash_erase_sector no longer works.
  esp32: Add scripts to init and mount filesystem.
  esp32: Enable frozen bytecode, with scripts stored in "modules/" dir.
  esp32/modesp: Increase flash_user_start position to 1Mbyte.
  esp32/Makefile: Add "erase" target for convenient erasure.
  esp32/sdkconfig: Reorder config settings to put common things together.
  esp32/sdkconfig: Change to use single core only.
  esp32: Add esp module.
  esp32/uart.c: Make sure uart ISR handler is all in iram.
  esp32/main.c: Use ESP_TASK_PRIO_MIN + 1 for mp_task's priority.
  esp32/Makefile: Use only bare-minimum flags when compiling .S files.
  esp32/Makefile: Rename "firmware" to "application".
  esp32: Update ESP IDF version.
  esp32/Makefile: Add declarations to build bootloader and partitions.
  esp32/Makefile: When deploying, write the application last.
  esp32/Makefile: Use $(INC) variable instead of listing include dirs.
  esp32/Makefile: Use locally built versions of freertos and newlib libs.
  esp32: Add low-level uart handler with ISR and ringbuf for stdin.
  esp32: Add machine.idle() function.
  esp32: Add machine.I2C class.
  esp32: Enable machine.time_pulse_us.
  esp32: Add initial implementation of machine.Pin class.
  esp32: Prepare main.c for using xTaskCreateStatic.
  esp32: Clean up mphalport.h.
  esp32: Add initial uos module.
  esp32: Clean up mpconfigport.h, enable more features.
  esp32: Use new reset function.
  esp32: Update to latest ESP IDF.
  esp32: Add idf-version target to Makefile, to track IDF commit.
  esp32: Initial port to ESP32.
2017-12-13 14:48:53 +11:00