Project Configuration¶
Introduction¶
ESP-IDF uses kconfiglib which is a Python-based extension to the Kconfig system which provides a compile-time project configuration mechanism. Kconfig is based around options of several types: integer, string, boolean. Kconfig files specify dependencies between options, default values of the options, the way the options are grouped together, etc.
For the complete list of available features please see Kconfig and kconfiglib extentions.
Using sdkconfig.defaults¶
In some cases, such as when sdkconfig file is under revision control, the fact that sdkconfig file gets changed by the build system may be inconvenient. The build system offers a way to avoid this, in the form of sdkconfig.defaults file. This file is never touched by the build system, and must be created manually. It can contain all the options which matter for the given application. The format is the same as that of the sdkconfig file. Once sdkconfig.defaults is created, sdkconfig can be deleted and added to the ignore list of the revision control system (e.g. .gitignore file for git). Project build targets will automatically create sdkconfig file, populated with the settings from sdkconfig.defaults file, and the rest of the settings will be set to their default values. Note that the build process will not override settings that are already in sdkconfig by ones from sdkconfig.defaults. For more information, see Custom sdkconfig defaults.
Kconfig Formatting Rules¶
The following attributes of Kconfig files are standardized:
Within any menu, option names should have a consistent prefix. The prefix length is currently set to at least 3 characters.
The indentation style is 4 characters created by spaces. All sub-items belonging to a parent item are indented by one level deeper. For example,
menuis indented by 0 characters, theconfiginside of the menu by 4 characters, the help of theconfigby 8 characters and the text of thehelpby 12 characters.No trailing spaces are allowed at the end of the lines.
The maximum length of options is set to 40 characters.
The maximum length of lines is set to 120 characters.
Lines cannot be wrapped by backslash (because there is a bug in earlier versions of
conf-idfwhich causes that Windows line endings are not recognized after a backslash).
Format checker¶
tools/check_kconfigs.py is provided for checking the Kconfig formatting
rules. The checker checks all Kconfig and Kconfig.projbuild files in
the ESP-IDF directory and generates a new file with suffix .new with some
recommendations how to fix issues (if there are any). Please note that the
checker cannot correct all rules and the responsibility of the developer is to
check and make final corrections in order to pass the tests. For example,
indentations will be corrected if there isn’t some misleading previous
formatting but it cannot come up with a common prefix for options inside a
menu.
Backward Compatibility of Kconfig Options¶
The standard Kconfig tools ignore unknown options in sdkconfig. So if a
developer has custom settings for options which are renamed in newer ESP-IDF
releases then the given setting for the option would be silently ignored.
Therefore, several features have been adopted to avoid this:
confgen.pyis used by the tool chain to pre-processsdkconfigfiles before anything else, for examplemenuconfig, would read them. As the consequence, the settings for old options will be kept and not ignored.confgen.pyrecursively finds allsdkconfig.renamefiles in ESP-IDF directory which contain old and newKconfigoption names. Old options are replaced by new ones in thesdkconfigfile.confgen.pypost-processessdkconfigfiles and generates all build outputs (sdkconfig.h,sdkconfig.cmake,auto.conf) by adding a list of compatibility statements, i.e. value of the old option is set the value of the new option (after modification). This is done in order to not break customer codes where old option might still be used.Deprecated options and their replacements are automatically generated by
confgen.py.
Configuration Options Reference¶
Subsequent sections contain the list of available ESP-IDF options, automatically generated from Kconfig files. Note that depending on the options selected, some options listed here may not be visible by default in the interface of menuconfig.
By convention, all option names are upper case with underscores. When Kconfig generates sdkconfig and sdkconfig.h files, option names are prefixed with CONFIG_. So if an option ENABLE_FOO is defined in a Kconfig file and selected in menuconfig, then sdkconfig and sdkconfig.h files will have CONFIG_ENABLE_FOO defined. In this reference, option names are also prefixed with CONFIG_, same as in the source code.
SDK tool configuration¶
Contains:
CONFIG_SDK_TOOLPREFIX¶
Compiler toolchain path/prefix
Found in: SDK tool configuration
The prefix/path that is used to call the toolchain. The default setting assumes a crosstool-ng gcc setup that is in your PATH.
CONFIG_SDK_PYTHON¶
Python interpreter
Found in: SDK tool configuration
The executable name/path that is used to run python.
(Note: This option is used with the legacy GNU Make build system only.)
CONFIG_SDK_MAKE_WARN_UNDEFINED_VARIABLES¶
‘make’ warns on undefined variables
Found in: SDK tool configuration
Adds –warn-undefined-variables to MAKEFLAGS. This causes make to print a warning any time an undefined variable is referenced.
This option helps find places where a variable reference is misspelled or otherwise missing, but it can be unwanted if you have Makefiles which depend on undefined variables expanding to an empty string.
(Note: this option is used with the legacy GNU Make build system only.)
CONFIG_SDK_TOOLCHAIN_SUPPORTS_TIME_WIDE_64_BITS¶
Toolchain supports time_t wide 64-bits
Found in: SDK tool configuration
Enable this option in case you have a custom toolchain which supports time_t wide 64-bits. This option checks time_t is 64-bits and disables ROM time functions to use the time functions from the toolchain instead. This option allows resolving the Y2K38 problem. See “Setup Linux Toolchain from Scratch” to build a custom toolchain which supports 64-bits time_t.
Note: ESP-IDF does not currently come with any pre-compiled toolchain that supports 64-bit wide time_t. This will change in a future major release, but currently 64-bit time_t requires a custom built toolchain.
Build type¶
Contains:
CONFIG_APP_BUILD_TYPE¶
Application build type
Found in: Build type
Select the way the application is built.
By default, the application is built as a binary file in a format compatible with the ESP32 bootloader. In addition to this application, 2nd stage bootloader is also built. Application and bootloader binaries can be written into flash and loaded/executed from there.
Another option, useful for only very small and limited applications, is to only link the .elf file of the application, such that it can be loaded directly into RAM over JTAG. Note that since IRAM and DRAM sizes are very limited, it is not possible to build any complex application this way. However for kinds of testing and debugging, this option may provide faster iterations, since the application does not need to be written into flash. Note that at the moment, ESP-IDF does not contain all the startup code required to initialize the CPUs and ROM memory (data/bss). Therefore it is necessary to execute a bit of ROM code prior to executing the application. A gdbinit file may look as follows:
# Connect to a running instance of OpenOCD target remote :3333 # Reset and halt the target mon reset halt # Run to a specific point in ROM code, # where most of initialization is complete. thb *0x40007d54 c # Load the application into RAM load # Run till app_main tb app_main c
Execute this gdbinit file as follows:
xtensa-esp32-elf-gdb build/app-name.elf -x gdbinit
Recommended sdkconfig.defaults for building loadable ELF files is as follows. CONFIG_APP_BUILD_TYPE_ELF_RAM is required, other options help reduce application memory footprint.
CONFIG_APP_BUILD_TYPE_ELF_RAM=y CONFIG_VFS_SUPPORT_TERMIOS= CONFIG_NEWLIB_NANO_FORMAT=y CONFIG_ESP_SYSTEM_PANIC_PRINT_HALT=y CONFIG_ESP_DEBUG_STUBS_ENABLE= CONFIG_ESP_ERR_TO_NAME_LOOKUP=
- Available options:
Default (binary application + 2nd stage bootloader) (APP_BUILD_TYPE_APP_2NDBOOT)
ELF file, loadable into RAM (EXPERIMENTAL)) (APP_BUILD_TYPE_ELF_RAM)
Partition Table¶
Contains:
CONFIG_PARTITION_TABLE_TYPE¶
Partition Table
Found in: Partition Table
The partition table to flash to the ESP32. The partition table determines where apps, data and other resources are expected to be found.
The predefined partition table CSV descriptions can be found in the components/partition_table directory. Otherwise it’s possible to create a new custom partition CSV for your application.
- Available options:
Single factory app, no OTA (PARTITION_TABLE_SINGLE_APP)
Factory app, two OTA definitions (PARTITION_TABLE_TWO_OTA)
Custom partition table CSV (PARTITION_TABLE_CUSTOM)
CONFIG_PARTITION_TABLE_CUSTOM_FILENAME¶
Custom partition CSV file
Found in: Partition Table
Name of the custom partition CSV filename. This path is evaluated relative to the project root directory.
CONFIG_PARTITION_TABLE_OFFSET¶
Offset of partition table
Found in: Partition Table
The address of partition table (by default 0x8000). Allows you to move the partition table, it gives more space for the bootloader. Note that the bootloader and app will both need to be compiled with the same PARTITION_TABLE_OFFSET value.
This number should be a multiple of 0x1000.
Note that partition offsets in the partition table CSV file may need to be changed if this value is set to a higher value. To have each partition offset adapt to the configured partition table offset, leave all partition offsets blank in the CSV file.
CONFIG_PARTITION_TABLE_MD5¶
Generate an MD5 checksum for the partition table
Found in: Partition Table
Generate an MD5 checksum for the partition table for protecting the integrity of the table. The generation should be turned off for legacy bootloaders which cannot recognize the MD5 checksum in the partition table.
Application manager¶
Contains:
CONFIG_APP_COMPILE_TIME_DATE¶
Use time/date stamp for app
Found in: Application manager
If set, then the app will be built with the current time/date stamp. It is stored in the app description structure. If not set, time/date stamp will be excluded from app image. This can be useful for getting the same binary image files made from the same source, but at different times.
CONFIG_APP_EXCLUDE_PROJECT_VER_VAR¶
Exclude PROJECT_VER from firmware image
Found in: Application manager
The PROJECT_VER variable from the build system will not affect the firmware image. This value will not be contained in the esp_app_desc structure.
CONFIG_APP_EXCLUDE_PROJECT_NAME_VAR¶
Exclude PROJECT_NAME from firmware image
Found in: Application manager
The PROJECT_NAME variable from the build system will not affect the firmware image. This value will not be contained in the esp_app_desc structure.
CONFIG_APP_PROJECT_VER_FROM_CONFIG¶
Get the project version from Kconfig
Found in: Application manager
If this is enabled, then config item APP_PROJECT_VER will be used for the variable PROJECT_VER. Other ways to set PROJECT_VER will be ignored.
CONFIG_APP_PROJECT_VER¶
CONFIG_APP_RETRIEVE_LEN_ELF_SHA¶
The length of APP ELF SHA is stored in RAM(chars)
Found in: Application manager
At startup, the app will read this many hex characters from the embedded APP ELF SHA-256 hash value and store it in static RAM. This ensures the app ELF SHA-256 value is always available if it needs to be printed by the panic handler code. Changing this value will change the size of a static buffer, in bytes.
Serial flasher config¶
Contains:
CONFIG_ESPTOOLPY_PORT¶
Default serial port
Found in: Serial flasher config
The serial port that’s connected to the ESP chip. This can be overridden by setting the ESPPORT environment variable.
This value is ignored when using the CMake-based build system or idf.py.
CONFIG_ESPTOOLPY_BAUD¶
Default baud rate
Found in: Serial flasher config
Default baud rate to use while communicating with the ESP chip. Can be overridden by setting the ESPBAUD variable.
This value is ignored when using the CMake-based build system or idf.py.
- Available options:
115200 baud (ESPTOOLPY_BAUD_115200B)
230400 baud (ESPTOOLPY_BAUD_230400B)
921600 baud (ESPTOOLPY_BAUD_921600B)
2Mbaud (ESPTOOLPY_BAUD_2MB)
Other baud rate (ESPTOOLPY_BAUD_OTHER)
CONFIG_ESPTOOLPY_BAUD_OTHER_VAL¶
Other baud rate value
Found in: Serial flasher config
CONFIG_ESPTOOLPY_COMPRESSED¶
Use compressed upload
Found in: Serial flasher config
The flasher tool can send data compressed using zlib, letting the ROM on the ESP chip decompress it on the fly before flashing it. For most payloads, this should result in a speed increase.
CONFIG_ESPTOOLPY_FLASHMODE¶
Flash SPI mode
Found in: Serial flasher config
Mode the flash chip is flashed in, as well as the default mode for the binary to run in.
- Available options:
QIO (ESPTOOLPY_FLASHMODE_QIO)
QOUT (ESPTOOLPY_FLASHMODE_QOUT)
DIO (ESPTOOLPY_FLASHMODE_DIO)
DOUT (ESPTOOLPY_FLASHMODE_DOUT)
CONFIG_ESPTOOLPY_FLASHFREQ¶
Flash SPI speed
Found in: Serial flasher config
The SPI flash frequency to be used.
- Available options:
80 MHz (ESPTOOLPY_FLASHFREQ_80M)
40 MHz (ESPTOOLPY_FLASHFREQ_40M)
26 MHz (ESPTOOLPY_FLASHFREQ_26M)
20 MHz (ESPTOOLPY_FLASHFREQ_20M)
CONFIG_ESPTOOLPY_FLASHSIZE¶
Flash size
Found in: Serial flasher config
SPI flash size, in megabytes
- Available options:
1 MB (ESPTOOLPY_FLASHSIZE_1MB)
2 MB (ESPTOOLPY_FLASHSIZE_2MB)
4 MB (ESPTOOLPY_FLASHSIZE_4MB)
8 MB (ESPTOOLPY_FLASHSIZE_8MB)
16 MB (ESPTOOLPY_FLASHSIZE_16MB)
CONFIG_ESPTOOLPY_FLASHSIZE_DETECT¶
Detect flash size when flashing bootloader
Found in: Serial flasher config
If this option is set, flashing the project will automatically detect the flash size of the target chip and update the bootloader image before it is flashed.
CONFIG_ESPTOOLPY_BEFORE¶
Before flashing
Found in: Serial flasher config
Configure whether esptool.py should reset the ESP32 before flashing.
Automatic resetting depends on the RTS & DTR signals being wired from the serial port to the ESP32. Most USB development boards do this internally.
- Available options:
Reset to bootloader (ESPTOOLPY_BEFORE_RESET)
No reset (ESPTOOLPY_BEFORE_NORESET)
CONFIG_ESPTOOLPY_AFTER¶
After flashing
Found in: Serial flasher config
Configure whether esptool.py should reset the ESP32 after flashing.
Automatic resetting depends on the RTS & DTR signals being wired from the serial port to the ESP32. Most USB development boards do this internally.
- Available options:
Reset after flashing (ESPTOOLPY_AFTER_RESET)
Stay in bootloader (ESPTOOLPY_AFTER_NORESET)
CONFIG_ESPTOOLPY_MONITOR_BAUD¶
‘idf.py monitor’ baud rate
Found in: Serial flasher config
Baud rate to use when running ‘idf.py monitor’ or ‘make monitor’ to view serial output from a running chip.
Can override by setting the MONITORBAUD environment variable.
- Available options:
9600 bps (ESPTOOLPY_MONITOR_BAUD_9600B)
57600 bps (ESPTOOLPY_MONITOR_BAUD_57600B)
115200 bps (ESPTOOLPY_MONITOR_BAUD_115200B)
230400 bps (ESPTOOLPY_MONITOR_BAUD_230400B)
921600 bps (ESPTOOLPY_MONITOR_BAUD_921600B)
2 Mbps (ESPTOOLPY_MONITOR_BAUD_2MB)
Custom baud rate (ESPTOOLPY_MONITOR_BAUD_OTHER)
CONFIG_ESPTOOLPY_MONITOR_BAUD_OTHER_VAL¶
Custom baud rate value
Found in: Serial flasher config
Bootloader config¶
Contains:
CONFIG_BOOTLOADER_COMPILER_OPTIMIZATION¶
Bootloader optimization Level
Found in: Bootloader config
This option sets compiler optimization level (gcc -O argument) for the bootloader.
The default “Size” setting will add the -0s flag to CFLAGS.
The “Debug” setting will add the -Og flag to CFLAGS.
The “Performance” setting will add the -O2 flag to CFLAGS.
The “None” setting will add the -O0 flag to CFLAGS.
Note that custom optimization levels may be unsupported.
- Available options:
Size (-Os) (BOOTLOADER_COMPILER_OPTIMIZATION_SIZE)
Debug (-Og) (BOOTLOADER_COMPILER_OPTIMIZATION_DEBUG)
Optimize for performance (-O2) (BOOTLOADER_COMPILER_OPTIMIZATION_PERF)
Debug without optimization (-O0) (BOOTLOADER_COMPILER_OPTIMIZATION_NONE)
CONFIG_BOOTLOADER_LOG_LEVEL¶
Bootloader log verbosity
Found in: Bootloader config
Specify how much output to see in bootloader logs.
- Available options:
No output (BOOTLOADER_LOG_LEVEL_NONE)
Error (BOOTLOADER_LOG_LEVEL_ERROR)
Warning (BOOTLOADER_LOG_LEVEL_WARN)
Info (BOOTLOADER_LOG_LEVEL_INFO)
Debug (BOOTLOADER_LOG_LEVEL_DEBUG)
Verbose (BOOTLOADER_LOG_LEVEL_VERBOSE)
CONFIG_BOOTLOADER_VDDSDIO_BOOST¶
VDDSDIO LDO voltage
Found in: Bootloader config
If this option is enabled, and VDDSDIO LDO is set to 1.8V (using eFuse or MTDI bootstrapping pin), bootloader will change LDO settings to output 1.9V instead. This helps prevent flash chip from browning out during flash programming operations.
This option has no effect if VDDSDIO is set to 3.3V, or if the internal VDDSDIO regulator is disabled via eFuse.
- Available options:
1.8V (BOOTLOADER_VDDSDIO_BOOST_1_8V)
1.9V (BOOTLOADER_VDDSDIO_BOOST_1_9V)
CONFIG_BOOTLOADER_FACTORY_RESET¶
GPIO triggers factory reset
Found in: Bootloader config
Allows to reset the device to factory settings: - clear one or more data partitions; - boot from “factory” partition. The factory reset will occur if there is a GPIO input pulled low while device starts up. See settings below.
CONFIG_BOOTLOADER_NUM_PIN_FACTORY_RESET¶
Number of the GPIO input for factory reset
Found in: Bootloader config > CONFIG_BOOTLOADER_FACTORY_RESET
The selected GPIO will be configured as an input with internal pull-up enabled. To trigger a factory reset, this GPIO must be pulled low on reset. Note that GPIO34-39 do not have an internal pullup and an external one must be provided.
CONFIG_BOOTLOADER_OTA_DATA_ERASE¶
Clear OTA data on factory reset (select factory partition)
Found in: Bootloader config > CONFIG_BOOTLOADER_FACTORY_RESET
The device will boot from “factory” partition (or OTA slot 0 if no factory partition is present) after a factory reset.
CONFIG_BOOTLOADER_DATA_FACTORY_RESET¶
Comma-separated names of partitions to clear on factory reset
Found in: Bootloader config > CONFIG_BOOTLOADER_FACTORY_RESET
Allows customers to select which data partitions will be erased while factory reset.
Specify the names of partitions as a comma-delimited with optional spaces for readability. (Like this: “nvs, phy_init, …”) Make sure that the name specified in the partition table and here are the same. Partitions of type “app” cannot be specified here.
CONFIG_BOOTLOADER_APP_TEST¶
GPIO triggers boot from test app partition
Found in: Bootloader config
Allows to run the test app from “TEST” partition. A boot from “test” partition will occur if there is a GPIO input pulled low while device starts up. See settings below.
CONFIG_BOOTLOADER_NUM_PIN_APP_TEST¶
Number of the GPIO input to boot TEST partition
Found in: Bootloader config > CONFIG_BOOTLOADER_APP_TEST
The selected GPIO will be configured as an input with internal pull-up enabled. To trigger a test app, this GPIO must be pulled low on reset. After the GPIO input is deactivated and the device reboots, the old application will boot. (factory or OTA[x]). Note that GPIO34-39 do not have an internal pullup and an external one must be provided.
CONFIG_BOOTLOADER_HOLD_TIME_GPIO¶
Hold time of GPIO for reset/test mode (seconds)
Found in: Bootloader config
The GPIO must be held low continuously for this period of time after reset before a factory reset or test partition boot (as applicable) is performed.
CONFIG_BOOTLOADER_WDT_ENABLE¶
Use RTC watchdog in start code
Found in: Bootloader config
Tracks the execution time of startup code. If the execution time is exceeded, the RTC_WDT will restart system. It is also useful to prevent a lock up in start code caused by an unstable power source. NOTE: Tracks the execution time starts from the bootloader code - re-set timeout, while selecting the source for slow_clk - and ends calling app_main. Re-set timeout is needed due to WDT uses a SLOW_CLK clock source. After changing a frequency slow_clk a time of WDT needs to re-set for new frequency. slow_clk depends on ESP32_RTC_CLK_SRC (INTERNAL_RC or EXTERNAL_CRYSTAL).
CONFIG_BOOTLOADER_WDT_DISABLE_IN_USER_CODE¶
Allows RTC watchdog disable in user code
Found in: Bootloader config > CONFIG_BOOTLOADER_WDT_ENABLE
If it is set, the client must itself reset or disable rtc_wdt in their code (app_main()). Otherwise rtc_wdt will be disabled before calling app_main function. Use function rtc_wdt_feed() for resetting counter of rtc_wdt. Use function rtc_wdt_disable() for disabling rtc_wdt.
CONFIG_BOOTLOADER_WDT_TIME_MS¶
Timeout for RTC watchdog (ms)
Found in: Bootloader config > CONFIG_BOOTLOADER_WDT_ENABLE
Verify that this parameter is correct and more then the execution time. Pay attention to options such as reset to factory, trigger test partition and encryption on boot - these options can increase the execution time. Note: RTC_WDT will reset while encryption operations will be performed.
CONFIG_BOOTLOADER_APP_ROLLBACK_ENABLE¶
Enable app rollback support
Found in: Bootloader config
After updating the app, the bootloader runs a new app with the “ESP_OTA_IMG_PENDING_VERIFY” state set. This state prevents the re-run of this app. After the first boot of the new app in the user code, the function should be called to confirm the operability of the app or vice versa about its non-operability. If the app is working, then it is marked as valid. Otherwise, it is marked as not valid and rolls back to the previous working app. A reboot is performed, and the app is booted before the software update. Note: If during the first boot a new app the power goes out or the WDT works, then roll back will happen. Rollback is possible only between the apps with the same security versions.
CONFIG_BOOTLOADER_APP_ANTI_ROLLBACK¶
Enable app anti-rollback support
Found in: Bootloader config > CONFIG_BOOTLOADER_APP_ROLLBACK_ENABLE
This option prevents rollback to previous firmware/application image with lower security version.
CONFIG_BOOTLOADER_APP_SECURE_VERSION¶
eFuse secure version of app
Found in: Bootloader config > CONFIG_BOOTLOADER_APP_ROLLBACK_ENABLE > CONFIG_BOOTLOADER_APP_ANTI_ROLLBACK
The secure version is the sequence number stored in the header of each firmware. The security version is set in the bootloader, version is recorded in the eFuse field as the number of set ones. The allocated number of bits in the efuse field for storing the security version is limited (see BOOTLOADER_APP_SEC_VER_SIZE_EFUSE_FIELD option).
Bootloader: When bootloader selects an app to boot, an app is selected that has a security version greater or equal that recorded in eFuse field. The app is booted with a higher (or equal) secure version.
The security version is worth increasing if in previous versions there is a significant vulnerability and their use is not acceptable.
Your partition table should has a scheme with ota_0 + ota_1 (without factory).
CONFIG_BOOTLOADER_APP_SEC_VER_SIZE_EFUSE_FIELD¶
Size of the efuse secure version field
Found in: Bootloader config > CONFIG_BOOTLOADER_APP_ROLLBACK_ENABLE > CONFIG_BOOTLOADER_APP_ANTI_ROLLBACK
The size of the efuse secure version field. Its length is limited to 32 bits for ESP32 and 16 bits for ESP32-S2. This determines how many times the security version can be increased.
CONFIG_BOOTLOADER_EFUSE_SECURE_VERSION_EMULATE¶
Emulate operations with efuse secure version(only test)
Found in: Bootloader config > CONFIG_BOOTLOADER_APP_ROLLBACK_ENABLE > CONFIG_BOOTLOADER_APP_ANTI_ROLLBACK
This option allow emulate read/write operations with efuse secure version. It allow to test anti-rollback implemention without permanent write eFuse bits. In partition table should be exist this partition emul_efuse, data, 5, , 0x2000.
CONFIG_BOOTLOADER_SKIP_VALIDATE_IN_DEEP_SLEEP¶
Skip image validation when exiting deep sleep
Found in: Bootloader config
This option disables the normal validation of an image coming out of deep sleep (checksums, SHA256, and signature). This is a trade-off between wakeup performance from deep sleep, and image integrity checks.
Only enable this if you know what you are doing. It should not be used in conjunction with using deep_sleep() entry and changing the active OTA partition as this would skip the validation upon first load of the new OTA partition.
CONFIG_BOOTLOADER_CUSTOM_RESERVE_RTC¶
Reserve RTC FAST memory for custom purposes
Found in: Bootloader config
This option allows the customer to place data in the RTC FAST memory, this area remains valid when rebooted, except for power loss. This memory is located at a fixed address and is available for both the bootloader and the application. (The application and bootoloader must be compiled with the same option). The RTC FAST memory has access only through PRO_CPU.
CONFIG_BOOTLOADER_CUSTOM_RESERVE_RTC_SIZE¶
Size in bytes for custom purposes
Found in: Bootloader config > CONFIG_BOOTLOADER_CUSTOM_RESERVE_RTC
This option reserves in RTC FAST memory the area for custom purposes. If you want to create your own bootloader and save more information in this area of memory, you can increase it. It must be a multiple of 4 bytes. This area (rtc_retain_mem_t) is reserved and has access from the bootloader and an application.
CONFIG_BOOTLOADER_FLASH_XMC_SUPPORT¶
Enable the support for flash chips of XMC (READ HELP FIRST)
Found in: Bootloader config
Perform the startup flow recommended by XMC. Please consult XMC for the details of this flow. XMC chips will be forbidden to be used, when this option is disabled.
DON’T DISABLE THIS UNLESS YOU KNOW WHAT YOU ARE DOING.
Security features¶
Contains:
CONFIG_SECURE_SIGNED_APPS_NO_SECURE_BOOT¶
Require signed app images
Found in: Security features
Require apps to be signed to verify their integrity.
This option uses the same app signature scheme as hardware secure boot, but unlike hardware secure boot it does not prevent the bootloader from being physically updated. This means that the device can be secured against remote network access, but not physical access. Compared to using hardware Secure Boot this option is much simpler to implement.
CONFIG_SECURE_SIGNED_APPS_SCHEME¶
App Signing Scheme
Found in: Security features
Select the Secure App signing scheme. Depends on the Chip Revision. There are two options: 1. ECDSA based secure boot scheme. (Only choice for Secure Boot V1) Supported in ESP32 and ESP32-ECO3. 2. The RSA based secure boot scheme. (Only choice for Secure Boot V2) Supported in ESP32-ECO3. (ESP32 Chip Revision 3 onwards)
- Available options:
ECDSA (SECURE_SIGNED_APPS_ECDSA_SCHEME)
Embeds the ECDSA public key in the bootloader and signs the application with an ECDSA key.
Refer to the documentation before enabling.
RSA (SECURE_SIGNED_APPS_RSA_SCHEME)
Appends the RSA-3072 based Signature block to the application. Refer to <Secure Boot Version 2 documentation link> before enabling.
CONFIG_SECURE_SIGNED_ON_BOOT_NO_SECURE_BOOT¶
Bootloader verifies app signatures
Found in: Security features
If this option is set, the bootloader will be compiled with code to verify that an app is signed before booting it.
If hardware secure boot is enabled, this option is always enabled and cannot be disabled. If hardware secure boot is not enabled, this option doesn’t add significant security by itself so most users will want to leave it disabled.
CONFIG_SECURE_SIGNED_ON_UPDATE_NO_SECURE_BOOT¶
Verify app signature on update
Found in: Security features
If this option is set, any OTA updated apps will have the signature verified before being considered valid.
When enabled, the signature is automatically checked whenever the esp_ota_ops.h APIs are used for OTA updates, or esp_image_format.h APIs are used to verify apps.
If hardware secure boot is enabled, this option is always enabled and cannot be disabled. If hardware secure boot is not enabled, this option still adds significant security against network-based attackers by preventing spoofing of OTA updates.
CONFIG_SECURE_BOOT¶
Enable hardware Secure Boot in bootloader (READ DOCS FIRST)
Found in: Security features
Build a bootloader which enables Secure Boot on first boot.
Once enabled, Secure Boot will not boot a modified bootloader. The bootloader will only load a partition table or boot an app if the data has a verified digital signature. There are implications for reflashing updated apps once secure boot is enabled.
When enabling secure boot, JTAG and ROM BASIC Interpreter are permanently disabled by default.
CONFIG_SECURE_BOOT_VERSION¶
Select secure boot version
Found in: Security features > CONFIG_SECURE_BOOT
Select the Secure Boot Version. Depends on the Chip Revision. Secure Boot V2 is the new RSA based secure boot scheme. Supported in ESP32-ECO3. (ESP32 Chip Revision 3 onwards) Secure Boot V1 is the AES based secure boot scheme. Supported in ESP32 and ESP32-ECO3.
- Available options:
Enable Secure Boot version 1 (SECURE_BOOT_V1_ENABLED)
Build a bootloader which enables secure boot version 1 on first boot. Refer to the Secure Boot section of the ESP-IDF Programmer’s Guide for this version before enabling.
Enable Secure Boot version 2 (SECURE_BOOT_V2_ENABLED)
Build a bootloader which enables Secure Boot version 2 on first boot. Refer to Secure Boot V2 section of the ESP-IDF Programmer’s Guide for this version before enabling.
CONFIG_SECURE_BOOT_BUILD_SIGNED_BINARIES¶
Sign binaries during build
Found in: Security features
Once secure boot or signed app requirement is enabled, app images are required to be signed.
If enabled (default), these binary files are signed as part of the build process. The file named in “Secure boot private signing key” will be used to sign the image.
If disabled, unsigned app/partition data will be built. They must be signed manually using espsecure.py. Version 1 to enable ECDSA Based Secure Boot and Version 2 to enable RSA based Secure Boot. (for example, on a remote signing server.)
CONFIG_SECURE_BOOT_SIGNING_KEY¶
Secure boot private signing key
Found in: Security features > CONFIG_SECURE_BOOT_BUILD_SIGNED_BINARIES
Path to the key file used to sign app images.
Key file is an ECDSA private key (NIST256p curve) in PEM format for Secure Boot V1. Key file is an RSA private key in PEM format for Secure Boot V2.
Path is evaluated relative to the project directory.
You can generate a new signing key by running the following command: espsecure.py generate_signing_key secure_boot_signing_key.pem
See the Secure Boot section of the ESP-IDF Programmer’s Guide for this version for details.
CONFIG_SECURE_BOOT_VERIFICATION_KEY¶
Secure boot public signature verification key
Found in: Security features
Path to a public key file used to verify signed images. Secure Boot V1: This ECDSA public key is compiled into the bootloader and/or app, to verify app images. Secure Boot V2: This RSA public key is compiled into the signature block at the end of the bootloader/app.
Key file is in raw binary format, and can be extracted from a PEM formatted private key using the espsecure.py extract_public_key command.
Refer to the Secure Boot section of the ESP-IDF Programmer’s Guide for this version before enabling.
CONFIG_SECURE_BOOT_INSECURE¶
Allow potentially insecure options
Found in: Security features
You can disable some of the default protections offered by secure boot, in order to enable testing or a custom combination of security features.
Only enable these options if you are very sure.
Refer to the Secure Boot section of the ESP-IDF Programmer’s Guide for this version before enabling.
CONFIG_SECURE_FLASH_ENC_ENABLED¶
Enable flash encryption on boot (READ DOCS FIRST)
Found in: Security features
If this option is set, flash contents will be encrypted by the bootloader on first boot.
Note: After first boot, the system will be permanently encrypted. Re-flashing an encrypted system is complicated and not always possible.
Read Flash Encryption before enabling.
CONFIG_SECURE_FLASH_ENCRYPTION_KEYSIZE¶
Size of generated AES-XTS key
Found in: Security features > CONFIG_SECURE_FLASH_ENC_ENABLED
Size of generated AES-XTS key.
AES-128 uses a 256-bit key (32 bytes) which occupies one Efuse key block. AES-256 uses a 512-bit key (64 bytes) which occupies two Efuse key blocks.
This setting is ignored if either type of key is already burned to Efuse before the first boot. In this case, the pre-burned key is used and no new key is generated.
- Available options:
AES-128 (256-bit key) (SECURE_FLASH_ENCRYPTION_AES128)
AES-256 (512-bit key) (SECURE_FLASH_ENCRYPTION_AES256)
CONFIG_SECURE_FLASH_ENCRYPTION_MODE¶
Enable usage mode
Found in: Security features > CONFIG_SECURE_FLASH_ENC_ENABLED
By default Development mode is enabled which allows UART bootloader to perform flash encryption operations
Select Release mode only for production or manufacturing. Once enabled you can not reflash using UART bootloader
Refer to the Secure Boot section of the ESP-IDF Programmer’s Guide for this version and Flash Encryption for details.
- Available options:
Development(NOT SECURE) (SECURE_FLASH_ENCRYPTION_MODE_DEVELOPMENT)
Release (SECURE_FLASH_ENCRYPTION_MODE_RELEASE)
Potentially insecure options¶
Contains:
CONFIG_SECURE_BOOT_ALLOW_JTAG¶
Allow JTAG Debugging
Found in: Security features > Potentially insecure options
If not set (default), the bootloader will permanently disable JTAG (across entire chip) on first boot when either secure boot or flash encryption is enabled.
Setting this option leaves JTAG on for debugging, which negates all protections of flash encryption and some of the protections of secure boot.
Only set this option in testing environments.
CONFIG_SECURE_BOOT_ALLOW_SHORT_APP_PARTITION¶
Allow app partition length not 64KB aligned
Found in: Security features > Potentially insecure options
If not set (default), app partition size must be a multiple of 64KB. App images are padded to 64KB length, and the bootloader checks any trailing bytes after the signature (before the next 64KB boundary) have not been written. This is because flash cache maps entire 64KB pages into the address space. This prevents an attacker from appending unverified data after the app image in the flash, causing it to be mapped into the address space.
Setting this option allows the app partition length to be unaligned, and disables padding of the app image to this length. It is generally not recommended to set this option, unless you have a legacy partitioning scheme which doesn’t support 64KB aligned partition lengths.
CONFIG_SECURE_BOOT_V2_ALLOW_EFUSE_RD_DIS¶
Allow additional read protecting of efuses
Found in: Security features > Potentially insecure options
If not set (default, recommended), on first boot the bootloader will burn the WR_DIS_RD_DIS efuse when Secure Boot is enabled. This prevents any more efuses from being read protected.
If this option is set, it will remain possible to write the EFUSE_RD_DIS efuse field after Secure Boot is enabled. This may allow an attacker to read-protect the BLK2 efuse (for ESP32) and BLOCK4-BLOCK10 (i.e. BLOCK_KEY0-BLOCK_KEY5)(for other chips) holding the public key digest, causing an immediate denial of service and possibly allowing an additional fault injection attack to bypass the signature protection.
NOTE: Once a BLOCK is read-protected, the application will read all zeros from that block
NOTE: If “UART ROM download mode (Permanently disabled (recommended))” or “UART ROM download mode (Permanently switch to Secure mode (recommended))” is set, then it is __NOT__ possible to read/write efuses using espefuse.py utility. However, efuse can be read/written from the application
CONFIG_SECURE_INSECURE_ALLOW_DL_MODE¶
Don’t automatically restrict UART download mode
Found in: Security features > Potentially insecure options
By default, enabling either flash encryption in release mode or secure boot will automatically disable UART download mode on ESP32 ECO3, or enable secure download mode on newer chips. This is recommended to reduce the attack surface of the chip.
To allow the full UART download mode to stay enabled, enable this option and ensure the options SECURE_DISABLE_ROM_DL_MODE and SECURE_ENABLE_SECURE_ROM_DL_MODE are disabled as applicable. This is not recommended.
CONFIG_SECURE_FLASH_UART_BOOTLOADER_ALLOW_ENC¶
Leave UART bootloader encryption enabled
Found in: Security features > Potentially insecure options
If not set (default), the bootloader will permanently disable UART bootloader encryption access on first boot. If set, the UART bootloader will still be able to access hardware encryption.
It is recommended to only set this option in testing environments.
CONFIG_SECURE_FLASH_UART_BOOTLOADER_ALLOW_CACHE¶
Leave UART bootloader flash cache enabled
Found in: Security features > Potentially insecure options
If not set (default), the bootloader will permanently disable UART bootloader flash cache access on first boot. If set, the UART bootloader will still be able to access the flash cache.
Only set this option in testing environments.
CONFIG_SECURE_FLASH_REQUIRE_ALREADY_ENABLED¶
Require flash encryption to be already enabled
Found in: Security features > Potentially insecure options
If not set (default), and flash encryption is not yet enabled in eFuses, the 2nd stage bootloader will enable flash encryption: generate the flash encryption key and program eFuses. If this option is set, and flash encryption is not yet enabled, the bootloader will error out and reboot. If flash encryption is enabled in eFuses, this option does not change the bootloader behavior.
Only use this option in testing environments, to avoid accidentally enabling flash encryption on the wrong device. The device needs to have flash encryption already enabled using espefuse.py.
CONFIG_SECURE_DISABLE_ROM_DL_MODE¶
Permanently disable ROM Download Mode
Found in: Security features
If set, during startup the app will burn an eFuse bit to permanently disable the UART ROM Download Mode. This prevents any future use of esptool.py, espefuse.py and similar tools.
Once disabled, if the SoC is booted with strapping pins set for ROM Download Mode then an error is printed instead.
It is recommended to enable this option in any production application where Flash Encryption and/or Secure Boot is enabled and access to Download Mode is not required.
It is also possible to permanently disable Download Mode by calling esp_efuse_disable_rom_download_mode() at runtime.
CONFIG_SECURE_ENABLE_SECURE_ROM_DL_MODE¶
Permanently switch to ROM UART Secure Download mode
Found in: Security features
If set, during startup the app will burn an eFuse bit to permanently switch the UART ROM Download Mode into a separate Secure Download mode. This option can only work if Download Mode is not already disabled by eFuse.
Secure Download mode limits the use of Download Mode functions to simple flash read, write and erase operations, plus a command to return a summary of currently enabled security features.
Secure Download mode is not compatible with the esptool.py flasher stub feature, espefuse.py, read/writing memory or registers, encrypted download, or any other features that interact with unsupported Download Mode commands.
Secure Download mode should be enabled in any application where Flash Encryption and/or Secure Boot is enabled. Disabling this option does not immediately cancel the benefits of the security features, but it increases the potential “attack surface” for an attacker to try and bypass them with a successful physical attack.
It is also possible to enable secure download mode at runtime by calling esp_efuse_enable_rom_secure_download_mode()
Compiler options¶
Contains:
CONFIG_COMPILER_OPTIMIZATION¶
Optimization Level
Found in: Compiler options
This option sets compiler optimization level (gcc -O argument) for the app.
The “Default” setting will add the -0g flag to CFLAGS.
The “Size” setting will add the -0s flag to CFLAGS.
The “Performance” setting will add the -O2 flag to CFLAGS.
The “None” setting will add the -O0 flag to CFLAGS.
The “Size” setting cause the compiled code to be smaller and faster, but may lead to difficulties of correlating code addresses to source file lines when debugging.
The “Performance” setting causes the compiled code to be larger and faster, but will be easier to correlated code addresses to source file lines.
“None” with -O0 produces compiled code without optimization.
Note that custom optimization levels may be unsupported.
Compiler optimization for the IDF bootloader is set separately, see the BOOTLOADER_COMPILER_OPTIMIZATION setting.
- Available options:
Debug (-Og) (COMPILER_OPTIMIZATION_DEFAULT)
Optimize for size (-Os) (COMPILER_OPTIMIZATION_SIZE)
Optimize for performance (-O2) (COMPILER_OPTIMIZATION_PERF)
Debug without optimization (-O0) (COMPILER_OPTIMIZATION_NONE)
CONFIG_COMPILER_OPTIMIZATION_ASSERTION_LEVEL¶
Assertion level
Found in: Compiler options
Assertions can be:
Enabled. Failure will print verbose assertion details. This is the default.
Set to “silent” to save code size (failed assertions will abort() but user needs to use the aborting address to find the line number with the failed assertion.)
Disabled entirely (not recommended for most configurations.) -DNDEBUG is added to CPPFLAGS in this case.
- Available options:
Enabled (COMPILER_OPTIMIZATION_ASSERTIONS_ENABLE)
Enable assertions. Assertion content and line number will be printed on failure.
Silent (saves code size) (COMPILER_OPTIMIZATION_ASSERTIONS_SILENT)
Enable silent assertions. Failed assertions will abort(), user needs to use the aborting address to find the line number with the failed assertion.
Disabled (sets -DNDEBUG) (COMPILER_OPTIMIZATION_ASSERTIONS_DISABLE)
If assertions are disabled, -DNDEBUG is added to CPPFLAGS.
CONFIG_COMPILER_CXX_EXCEPTIONS¶
Enable C++ exceptions
Found in: Compiler options
Enabling this option compiles all IDF C++ files with exception support enabled.
Disabling this option disables C++ exception support in all compiled files, and any libstdc++ code which throws an exception will abort instead.
Enabling this option currently adds an additional ~500 bytes of heap overhead when an exception is thrown in user code for the first time.
Contains:
CONFIG_COMPILER_CXX_EXCEPTIONS_EMG_POOL_SIZE¶
Emergency Pool Size
Found in: Compiler options > CONFIG_COMPILER_CXX_EXCEPTIONS
Size (in bytes) of the emergency memory pool for C++ exceptions. This pool will be used to allocate memory for thrown exceptions when there is not enough memory on the heap.
CONFIG_COMPILER_CXX_RTTI¶
Enable C++ run-time type info (RTTI)
Found in: Compiler options
Enabling this option compiles all C++ files with RTTI support enabled. This increases binary size (typically by tens of kB) but allows using dynamic_cast conversion and typeid operator.
CONFIG_COMPILER_STACK_CHECK_MODE¶
Stack smashing protection mode
Found in: Compiler options
Stack smashing protection mode. Emit extra code to check for buffer overflows, such as stack smashing attacks. This is done by adding a guard variable to functions with vulnerable objects. The guards are initialized when a function is entered and then checked when the function exits. If a guard check fails, program is halted. Protection has the following modes:
In NORMAL mode (GCC flag: -fstack-protector) only functions that call alloca, and functions with buffers larger than 8 bytes are protected.
STRONG mode (GCC flag: -fstack-protector-strong) is like NORMAL, but includes additional functions to be protected – those that have local array definitions, or have references to local frame addresses.
In OVERALL mode (GCC flag: -fstack-protector-all) all functions are protected.
Modes have the following impact on code performance and coverage:
performance: NORMAL > STRONG > OVERALL
coverage: NORMAL < STRONG < OVERALL
- Available options:
None (COMPILER_STACK_CHECK_MODE_NONE)
Normal (COMPILER_STACK_CHECK_MODE_NORM)
Strong (COMPILER_STACK_CHECK_MODE_STRONG)
Overall (COMPILER_STACK_CHECK_MODE_ALL)
CONFIG_COMPILER_WARN_WRITE_STRINGS¶
Enable -Wwrite-strings warning flag
Found in: Compiler options
Adds -Wwrite-strings flag for the C/C++ compilers.
For C, this gives string constants the type
const char[]so that copying the address of one into a non-constchar \*pointer produces a warning. This warning helps to find at compile time code that tries to write into a string constant.For C++, this warns about the deprecated conversion from string literals to
char \*.
CONFIG_COMPILER_DISABLE_GCC8_WARNINGS¶
Disable new warnings introduced in GCC 6 - 8
Found in: Compiler options
Enable this option if using GCC 6 or newer, and wanting to disable warnings which don’t appear with GCC 5.
Component config¶
Contains:
HTTP Server¶
Contains:
CONFIG_HTTPD_MAX_REQ_HDR_LEN¶
Max HTTP Request Header Length
Found in: Component config > HTTP Server
This sets the maximum supported size of headers section in HTTP request packet to be processed by the server
CONFIG_HTTPD_MAX_URI_LEN¶
Max HTTP URI Length
Found in: Component config > HTTP Server
This sets the maximum supported size of HTTP request URI to be processed by the server
CONFIG_HTTPD_ERR_RESP_NO_DELAY¶
Use TCP_NODELAY socket option when sending HTTP error responses
Found in: Component config > HTTP Server
Using TCP_NODEALY socket option ensures that HTTP error response reaches the client before the underlying socket is closed. Please note that turning this off may cause multiple test failures
CONFIG_HTTPD_PURGE_BUF_LEN¶
Length of temporary buffer for purging data
Found in: Component config > HTTP Server
This sets the size of the temporary buffer used to receive and discard any remaining data that is received from the HTTP client in the request, but not processed as part of the server HTTP request handler.
If the remaining data is larger than the available buffer size, the buffer will be filled in multiple iterations. The buffer should be small enough to fit on the stack, but large enough to avoid excessive iterations.
CONFIG_HTTPD_LOG_PURGE_DATA¶
Log purged content data at Debug level
Found in: Component config > HTTP Server
Enabling this will log discarded binary HTTP request data at Debug level. For large content data this may not be desirable as it will clutter the log.
CONFIG_HTTPD_WS_SUPPORT¶
WebSocket server support
Found in: Component config > HTTP Server
This sets the WebSocket server support.
ESP HTTP client¶
Contains:
CONFIG_ESP_HTTP_CLIENT_ENABLE_HTTPS¶
Enable https
Found in: Component config > ESP HTTP client
This option will enable https protocol by linking mbedtls library and initializing SSL transport
CONFIG_ESP_HTTP_CLIENT_ENABLE_BASIC_AUTH¶
Enable HTTP Basic Authentication
Found in: Component config > ESP HTTP client
This option will enable HTTP Basic Authentication. It is disabled by default as Basic auth uses unencrypted encoding, so it introduces a vulnerability when not using TLS
ESP HTTPS server¶
Contains:
CONFIG_ESP_HTTPS_SERVER_ENABLE¶
Enable ESP_HTTPS_SERVER component
Found in: Component config > ESP HTTPS server
Enable ESP HTTPS server component
High resolution timer (esp_timer)¶
Contains:
CONFIG_ESP_TIMER_PROFILING¶
Enable esp_timer profiling features
Found in: Component config > High resolution timer (esp_timer)
If enabled, esp_timer_dump will dump information such as number of times the timer was started, number of times the timer has triggered, and the total time it took for the callback to run. This option has some effect on timer performance and the amount of memory used for timer storage, and should only be used for debugging/testing purposes.
CONFIG_ESP_TIMER_TASK_STACK_SIZE¶
High-resolution timer task stack size
Found in: Component config > High resolution timer (esp_timer)
Configure the stack size of “timer_task” task. This task is used to dispatch callbacks of timers created using ets_timer and esp_timer APIs. If you are seing stack overflow errors in timer task, increase this value.
Note that this is not the same as FreeRTOS timer task. To configure FreeRTOS timer task size, see “FreeRTOS timer task stack size” option in “FreeRTOS” menu.
CONFIG_ESP_TIMER_IMPL¶
Hardware timer to use for esp_timer
Found in: Component config > High resolution timer (esp_timer)
esp_timer APIs can be implemented using different hardware timers.
“FRC2 (legacy)” implementation has been used in ESP-IDF v2.x - v4.1.
“LAC timer of Timer Group 0” implementation is simpler, and has smaller run time overhead because software handling of timer overflow is not needed.
“SYSTIMER” implementation is similar to “LAC timer of Timer Group 0” but for ESP32-S2 chip.
- Available options:
FRC2 (legacy) timer (ESP_TIMER_IMPL_FRC2)
LAC timer of Timer Group 0 (ESP_TIMER_IMPL_TG0_LAC)
SYSTIMER (ESP_TIMER_IMPL_SYSTIMER)
FAT Filesystem support¶
Contains:
CONFIG_FATFS_CHOOSE_CODEPAGE¶
OEM Code Page
Found in: Component config > FAT Filesystem support
OEM code page used for file name encodings.
If “Dynamic” is selected, code page can be chosen at runtime using f_setcp function. Note that choosing this option will increase application size by ~480kB.
- Available options:
Dynamic (all code pages supported) (FATFS_CODEPAGE_DYNAMIC)
US (CP437) (FATFS_CODEPAGE_437)
Arabic (CP720) (FATFS_CODEPAGE_720)
Greek (CP737) (FATFS_CODEPAGE_737)
KBL (CP771) (FATFS_CODEPAGE_771)
Baltic (CP775) (FATFS_CODEPAGE_775)
Latin 1 (CP850) (FATFS_CODEPAGE_850)
Latin 2 (CP852) (FATFS_CODEPAGE_852)
Cyrillic (CP855) (FATFS_CODEPAGE_855)
Turkish (CP857) (FATFS_CODEPAGE_857)
Portugese (CP860) (FATFS_CODEPAGE_860)
Icelandic (CP861) (FATFS_CODEPAGE_861)
Hebrew (CP862) (FATFS_CODEPAGE_862)
Canadian French (CP863) (FATFS_CODEPAGE_863)
Arabic (CP864) (FATFS_CODEPAGE_864)
Nordic (CP865) (FATFS_CODEPAGE_865)
Russian (CP866) (FATFS_CODEPAGE_866)
Greek 2 (CP869) (FATFS_CODEPAGE_869)
Japanese (DBCS) (CP932) (FATFS_CODEPAGE_932)
Simplified Chinese (DBCS) (CP936) (FATFS_CODEPAGE_936)
Korean (DBCS) (CP949) (FATFS_CODEPAGE_949)
Traditional Chinese (DBCS) (CP950) (FATFS_CODEPAGE_950)
CONFIG_FATFS_LONG_FILENAMES¶
Long filename support
Found in: Component config > FAT Filesystem support
Support long filenames in FAT. Long filename data increases memory usage. FATFS can be configured to store the buffer for long filename data in stack or heap.
- Available options:
No long filenames (FATFS_LFN_NONE)
Long filename buffer in heap (FATFS_LFN_HEAP)
Long filename buffer on stack (FATFS_LFN_STACK)
CONFIG_FATFS_MAX_LFN¶
Max long filename length
Found in: Component config > FAT Filesystem support
Maximum long filename length. Can be reduced to save RAM.
CONFIG_FATFS_API_ENCODING¶
API character encoding
Found in: Component config > FAT Filesystem support
Choose encoding for character and string arguments/returns when using FATFS APIs. The encoding of arguments will usually depend on text editor settings.
- Available options:
API uses ANSI/OEM encoding (FATFS_API_ENCODING_ANSI_OEM)
API uses UTF-16 encoding (FATFS_API_ENCODING_UTF_16)
API uses UTF-8 encoding (FATFS_API_ENCODING_UTF_8)
CONFIG_FATFS_FS_LOCK¶
Number of simultaneously open files protected by lock function
Found in: Component config > FAT Filesystem support
This option sets the FATFS configuration value _FS_LOCK. The option _FS_LOCK switches file lock function to control duplicated file open and illegal operation to open objects.
* 0: Disable file lock function. To avoid volume corruption, application should avoid illegal open, remove and rename to the open objects.
* >0: Enable file lock function. The value defines how many files/sub-directories can be opened simultaneously under file lock control.
Note that the file lock control is independent of re-entrancy.
CONFIG_FATFS_TIMEOUT_MS¶
Timeout for acquiring a file lock, ms
Found in: Component config > FAT Filesystem support
This option sets FATFS configuration value _FS_TIMEOUT, scaled to milliseconds. Sets the number of milliseconds FATFS will wait to acquire a mutex when operating on an open file. For example, if one task is performing a lenghty operation, another task will wait for the first task to release the lock, and time out after amount of time set by this option.
CONFIG_FATFS_PER_FILE_CACHE¶
Use separate cache for each file
Found in: Component config > FAT Filesystem support
This option affects FATFS configuration value _FS_TINY.
If this option is set, _FS_TINY is 0, and each open file has its own cache, size of the cache is equal to the _MAX_SS variable (512 or 4096 bytes). This option uses more RAM if more than 1 file is open, but needs less reads and writes to the storage for some operations.
If this option is not set, _FS_TINY is 1, and single cache is used for all open files, size is also equal to _MAX_SS variable. This reduces the amount of heap used when multiple files are open, but increases the number of read and write operations which FATFS needs to make.
CONFIG_FATFS_ALLOC_PREFER_EXTRAM¶
Perfer external RAM when allocating FATFS buffers
Found in: Component config > FAT Filesystem support
When the option is enabled, internal buffers used by FATFS will be allocated from external RAM. If the allocation from external RAM fails, the buffer will be allocated from the internal RAM. Disable this option if optimizing for performance. Enable this option if optimizing for internal memory size.
Core dump¶
Contains:
CONFIG_ESP32_COREDUMP_TO_FLASH_OR_UART¶
Data destination
Found in: Component config > Core dump
Select place to store core dump: flash, uart or none (to disable core dumps generation).
Core dumps to Flash are not available if PSRAM is used for task stacks.
If core dump is configured to be stored in flash and custom partition table is used add corresponding entry to your CSV. For examples, please see predefined partition table CSV descriptions in the components/partition_table directory.
- Available options:
Flash (ESP32_ENABLE_COREDUMP_TO_FLASH)
UART (ESP32_ENABLE_COREDUMP_TO_UART)
None (ESP32_ENABLE_COREDUMP_TO_NONE)
CONFIG_ESP32_COREDUMP_DATA_FORMAT¶
Core dump data format
Found in: Component config > Core dump
Select the data format for core dump.
- Available options:
Binary format (ESP32_COREDUMP_DATA_FORMAT_BIN)
ELF format (ESP32_COREDUMP_DATA_FORMAT_ELF)
CONFIG_ESP32_COREDUMP_CHECKSUM¶
Core dump data integrity check
Found in: Component config > Core dump
Select the integrity check for the core dump.
- Available options:
Use CRC32 for integrity verification (ESP32_COREDUMP_CHECKSUM_CRC32)
Use SHA256 for integrity verification (ESP32_COREDUMP_CHECKSUM_SHA256)
CONFIG_ESP32_CORE_DUMP_MAX_TASKS_NUM¶
Maximum number of tasks
Found in: Component config > Core dump
Maximum number of tasks snapshots in core dump.
CONFIG_ESP32_CORE_DUMP_UART_DELAY¶
Delay before print to UART
Found in: Component config > Core dump
Config delay (in ms) before printing core dump to UART. Delay can be interrupted by pressing Enter key.
CONFIG_ESP32_CORE_DUMP_STACK_SIZE¶
Reserved stack size
Found in: Component config > Core dump
Size of the memory to be reserved for core dump stack. If 0 core dump process will run on the stack of crashed task/ISR, otherwise special stack will be allocated. To ensure that core dump itself will not overflow task/ISR stack set this to the value above 800. NOTE: It eats DRAM.
CONFIG_ESP32_CORE_DUMP_DECODE¶
Handling of UART core dumps in IDF Monitor
Found in: Component config > Core dump
- Available options:
Decode and show summary (info_corefile) (ESP32_CORE_DUMP_DECODE_INFO)
Don’t decode (ESP32_CORE_DUMP_DECODE_DISABLE)
mbedTLS¶
Contains:
CONFIG_MBEDTLS_MEM_ALLOC_MODE¶
Memory allocation strategy
Found in: Component config > mbedTLS
Allocation strategy for mbedTLS, essentially provides ability to allocate all required dynamic allocations from,
Internal DRAM memory only
External SPIRAM memory only
Either internal or external memory based on default malloc() behavior in ESP-IDF
Custom allocation mode, by overwriting calloc()/free() using mbedtls_platform_set_calloc_free() function
Internal IRAM memory wherever applicable else internal DRAM
Recommended mode here is always internal (*), since that is most preferred from security perspective. But if application requirement does not allow sufficient free internal memory then alternate mode can be selected.
(*) In case of ESP32-S2, hardware allows encryption of external SPIRAM contents provided hardware flash encryption feature is enabled. In that case, using external SPIRAM allocation strategy is also safe choice from security perspective.
- Available options:
Internal memory (MBEDTLS_INTERNAL_MEM_ALLOC)
External SPIRAM (MBEDTLS_EXTERNAL_MEM_ALLOC)
Default alloc mode (MBEDTLS_DEFAULT_MEM_ALLOC)
Custom alloc mode (MBEDTLS_CUSTOM_MEM_ALLOC)
Internal IRAM (MBEDTLS_IRAM_8BIT_MEM_ALLOC)
Allows to use IRAM memory region as 8bit accessible region.
TLS input and output buffers will be allocated in IRAM section which is 32bit aligned memory. Every unaligned (8bit or 16bit) access will result in an exception and incur penalty of certain clock cycles per unaligned read/write.
CONFIG_MBEDTLS_SSL_MAX_CONTENT_LEN¶
TLS maximum message content length
Found in: Component config > mbedTLS
Maximum TLS message length (in bytes) supported by mbedTLS.
16384 is the default and this value is required to comply fully with TLS standards.
However you can set a lower value in order to save RAM. This is safe if the other end of the connection supports Maximum Fragment Length Negotiation Extension (max_fragment_length, see RFC6066) or you know for certain that it will never send a message longer than a certain number of bytes.
If the value is set too low, symptoms are a failed TLS handshake or a return value of MBEDTLS_ERR_SSL_INVALID_RECORD (-0x7200).
CONFIG_MBEDTLS_ASYMMETRIC_CONTENT_LEN¶
Asymmetric in/out fragment length
Found in: Component config > mbedTLS
If enabled, this option allows customizing TLS in/out fragment length in asymmetric way. Please note that enabling this with default values saves 12KB of dynamic memory per TLS connection.
CONFIG_MBEDTLS_SSL_IN_CONTENT_LEN¶
TLS maximum incoming fragment length
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ASYMMETRIC_CONTENT_LEN
This defines maximum incoming fragment length, overriding default maximum content length (MBEDTLS_SSL_MAX_CONTENT_LEN).
CONFIG_MBEDTLS_SSL_OUT_CONTENT_LEN¶
TLS maximum outgoing fragment length
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ASYMMETRIC_CONTENT_LEN
This defines maximum outgoing fragment length, overriding default maximum content length (MBEDTLS_SSL_MAX_CONTENT_LEN).
CONFIG_MBEDTLS_DYNAMIC_BUFFER¶
Using dynamic TX/RX buffer
Found in: Component config > mbedTLS
Using dynamic TX/RX buffer. After enabling this option, mbedTLS will allocate TX buffer when need to send data and then free it if all data is sent, allocate RX buffer when need to receive data and then free it when all data is used or read by upper layer.
By default, when SSL is initialized, mbedTLS also allocate TX and RX buffer with the default value of “MBEDTLS_SSL_OUT_CONTENT_LEN” or “MBEDTLS_SSL_IN_CONTENT_LEN”, so to save more heap, users can set the options to be an appropriate value.
CONFIG_MBEDTLS_DYNAMIC_FREE_PEER_CERT¶
Free SSL peer certificate after its usage
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_DYNAMIC_BUFFER
Free peer certificate after its usage in handshake process.
CONFIG_MBEDTLS_DYNAMIC_FREE_CONFIG_DATA¶
Free private key and DHM data after its usage
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_DYNAMIC_BUFFER
Free private key and DHM data after its usage in handshake process.
The option will decrease heap cost when handshake, but also lead to problem:
Becasue all certificate, private key and DHM data are freed so users should register certificate and private key to ssl config object again.
CONFIG_MBEDTLS_DYNAMIC_FREE_CA_CERT¶
Free SSL CA certificate after its usage
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_DYNAMIC_BUFFER > CONFIG_MBEDTLS_DYNAMIC_FREE_CONFIG_DATA
Free CA certificate after its usage in the handshake process. This option will decrease the heap footprint for the TLS handshake, but may lead to a problem: If the respective ssl object needs to perform the TLS handshake again, the CA certificate should once again be registered to the ssl object.
CONFIG_MBEDTLS_DEBUG¶
Enable mbedTLS debugging
Found in: Component config > mbedTLS
Enable mbedTLS debugging functions at compile time.
If this option is enabled, you can include “mbedtls/esp_debug.h” and call mbedtls_esp_enable_debug_log() at runtime in order to enable mbedTLS debug output via the ESP log mechanism.
CONFIG_MBEDTLS_DEBUG_LEVEL¶
Set mbedTLS debugging level
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_DEBUG
Set mbedTLS debugging level
- Available options:
Warning (MBEDTLS_DEBUG_LEVEL_WARN)
Info (MBEDTLS_DEBUG_LEVEL_INFO)
Debug (MBEDTLS_DEBUG_LEVEL_DEBUG)
Verbose (MBEDTLS_DEBUG_LEVEL_VERBOSE)
Certificate Bundle¶
Contains:
CONFIG_MBEDTLS_CERTIFICATE_BUNDLE¶
Enable trusted root certificate bundle
Found in: Component config > mbedTLS > Certificate Bundle
Enable support for large number of default root certificates
When enabled this option allows user to store default as well as customer specific root certificates in compressed format rather than storing full certificate. For the root certificates the public key and the subject name will be stored.
CONFIG_MBEDTLS_DEFAULT_CERTIFICATE_BUNDLE¶
Default certificate bundle options
Found in: Component config > mbedTLS > Certificate Bundle > CONFIG_MBEDTLS_CERTIFICATE_BUNDLE
- Available options:
Use the full default certificate bundle (MBEDTLS_CERTIFICATE_BUNDLE_DEFAULT_FULL)
Use only the most common certificates from the default bundles (MBEDTLS_CERTIFICATE_BUNDLE_DEFAULT_CMN)
Use only the most common certificates from the default bundles, reducing the size with 50%, while still having around 99% coverage.
Do not use the default certificate bundle (MBEDTLS_CERTIFICATE_BUNDLE_DEFAULT_NONE)
CONFIG_MBEDTLS_CUSTOM_CERTIFICATE_BUNDLE¶
Add custom certificates to the default bundle
Found in: Component config > mbedTLS > Certificate Bundle > CONFIG_MBEDTLS_CERTIFICATE_BUNDLE
CONFIG_MBEDTLS_CUSTOM_CERTIFICATE_BUNDLE_PATH¶
Custom certificate bundle path
Found in: Component config > mbedTLS > Certificate Bundle > CONFIG_MBEDTLS_CERTIFICATE_BUNDLE > CONFIG_MBEDTLS_CUSTOM_CERTIFICATE_BUNDLE
Name of the custom certificate directory or file. This path is evaluated relative to the project root directory.
CONFIG_MBEDTLS_ECP_RESTARTABLE¶
Enable mbedTLS ecp restartable
Found in: Component config > mbedTLS
Enable “non-blocking” ECC operations that can return early and be resumed.
CONFIG_MBEDTLS_CMAC_C¶
Enable CMAC mode for block ciphers
Found in: Component config > mbedTLS
Enable the CMAC (Cipher-based Message Authentication Code) mode for block ciphers.
CONFIG_MBEDTLS_HARDWARE_AES¶
Enable hardware AES acceleration
Found in: Component config > mbedTLS
Enable hardware accelerated AES encryption & decryption.
Note that if the ESP32 CPU is running at 240MHz, hardware AES does not offer any speed boost over software AES.
CONFIG_MBEDTLS_AES_USE_INTERRUPT¶
Use interrupt for long AES operations
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_HARDWARE_AES
Use an interrupt to coordinate long AES operations.
This allows other code to run on the CPU while an AES operation is pending. Otherwise the CPU busy-waits.
CONFIG_MBEDTLS_HARDWARE_GCM¶
Enable partially hardware accelerated GCM
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_HARDWARE_AES
Enable partially hardware accelerated GCM. GHASH calculation is still done in software.
If MBEDTLS_HARDWARE_GCM is disabled and MBEDTLS_HARDWARE_AES is enabled then mbedTLS will still use the hardware accelerated AES block operation, but on a single block at a time.
CONFIG_MBEDTLS_HARDWARE_MPI¶
Enable hardware MPI (bignum) acceleration
Found in: Component config > mbedTLS
Enable hardware accelerated multiple precision integer operations.
Hardware accelerated multiplication, modulo multiplication, and modular exponentiation for up to 4096 bit results.
These operations are used by RSA.
CONFIG_MBEDTLS_HARDWARE_SHA¶
Enable hardware SHA acceleration
Found in: Component config > mbedTLS
Enable hardware accelerated SHA1, SHA256, SHA384 & SHA512 in mbedTLS.
Due to a hardware limitation, on the ESP32 hardware acceleration is only guaranteed if SHA digests are calculated one at a time. If more than one SHA digest is calculated at the same time, one will be calculated fully in hardware and the rest will be calculated (at least partially calculated) in software. This happens automatically.
SHA hardware acceleration is faster than software in some situations but slower in others. You should benchmark to find the best setting for you.
CONFIG_MBEDTLS_ATCA_HW_ECDSA_SIGN¶
Enable hardware ECDSA sign acceleration when using ATECC608A
Found in: Component config > mbedTLS
This option enables hardware acceleration for ECDSA sign function, only when using ATECC608A cryptoauth chip (integrated with ESP32-WROOM-32SE)
CONFIG_MBEDTLS_ATCA_HW_ECDSA_VERIFY¶
Enable hardware ECDSA verify acceleration when using ATECC608A
Found in: Component config > mbedTLS
This option enables hardware acceleration for ECDSA sign function, only when using ATECC608A cryptoauth chip (integrated with ESP32-WROOM-32SE)
CONFIG_MBEDTLS_HAVE_TIME¶
Enable mbedtls time
Found in: Component config > mbedTLS
System has time.h and time(). The time does not need to be correct, only time differences are used.
CONFIG_MBEDTLS_HAVE_TIME_DATE¶
Enable mbedtls certificate expiry check
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_HAVE_TIME
System has time.h and time(), gmtime() and the clock is correct. The time needs to be correct (not necesarily very accurate, but at least the date should be correct). This is used to verify the validity period of X.509 certificates.
It is suggested that you should get the real time by “SNTP”.
CONFIG_MBEDTLS_ECDSA_DETERMINISTIC¶
Enable deterministic ECDSA
Found in: Component config > mbedTLS
Standard ECDSA is “fragile” in the sense that lack of entropy when signing may result in a compromise of the long-term signing key.
CONFIG_MBEDTLS_SHA512_C¶
Enable the SHA-384 and SHA-512 cryptographic hash algorithms
Found in: Component config > mbedTLS
Enable MBEDTLS_SHA512_C adds support for SHA-384 and SHA-512.
CONFIG_MBEDTLS_TLS_MODE¶
TLS Protocol Role
Found in: Component config > mbedTLS
mbedTLS can be compiled with protocol support for the TLS server, TLS client, or both server and client.
Reducing the number of TLS roles supported saves code size.
- Available options:
Server & Client (MBEDTLS_TLS_SERVER_AND_CLIENT)
Server (MBEDTLS_TLS_SERVER_ONLY)
Client (MBEDTLS_TLS_CLIENT_ONLY)
None (MBEDTLS_TLS_DISABLED)
TLS Key Exchange Methods¶
Contains:
CONFIG_MBEDTLS_PSK_MODES¶
Enable pre-shared-key ciphersuites
Found in: Component config > mbedTLS > TLS Key Exchange Methods
Enable to show configuration for different types of pre-shared-key TLS authentatication methods.
Leaving this options disabled will save code size if they are not used.
CONFIG_MBEDTLS_KEY_EXCHANGE_PSK¶
Enable PSK based ciphersuite modes
Found in: Component config > mbedTLS > TLS Key Exchange Methods > CONFIG_MBEDTLS_PSK_MODES
Enable to support symmetric key PSK (pre-shared-key) TLS key exchange modes.
CONFIG_MBEDTLS_KEY_EXCHANGE_DHE_PSK¶
Enable DHE-PSK based ciphersuite modes
Found in: Component config > mbedTLS > TLS Key Exchange Methods > CONFIG_MBEDTLS_PSK_MODES
Enable to support Diffie-Hellman PSK (pre-shared-key) TLS authentication modes.
CONFIG_MBEDTLS_KEY_EXCHANGE_ECDHE_PSK¶
Enable ECDHE-PSK based ciphersuite modes
Found in: Component config > mbedTLS > TLS Key Exchange Methods > CONFIG_MBEDTLS_PSK_MODES
Enable to support Elliptic-Curve-Diffie-Hellman PSK (pre-shared-key) TLS authentication modes.
CONFIG_MBEDTLS_KEY_EXCHANGE_RSA_PSK¶
Enable RSA-PSK based ciphersuite modes
Found in: Component config > mbedTLS > TLS Key Exchange Methods > CONFIG_MBEDTLS_PSK_MODES
Enable to support RSA PSK (pre-shared-key) TLS authentication modes.
CONFIG_MBEDTLS_KEY_EXCHANGE_RSA¶
Enable RSA-only based ciphersuite modes
Found in: Component config > mbedTLS > TLS Key Exchange Methods
Enable to support ciphersuites with prefix TLS-RSA-WITH-
CONFIG_MBEDTLS_KEY_EXCHANGE_DHE_RSA¶
Enable DHE-RSA based ciphersuite modes
Found in: Component config > mbedTLS > TLS Key Exchange Methods
Enable to support ciphersuites with prefix TLS-DHE-RSA-WITH-
CONFIG_MBEDTLS_KEY_EXCHANGE_ELLIPTIC_CURVE¶
Support Elliptic Curve based ciphersuites
Found in: Component config > mbedTLS > TLS Key Exchange Methods
Enable to show Elliptic Curve based ciphersuite mode options.
Disabling all Elliptic Curve ciphersuites saves code size and can give slightly faster TLS handshakes, provided the server supports RSA-only ciphersuite modes.
CONFIG_MBEDTLS_KEY_EXCHANGE_ECDHE_RSA¶
Enable ECDHE-RSA based ciphersuite modes
Found in: Component config > mbedTLS > TLS Key Exchange Methods > CONFIG_MBEDTLS_KEY_EXCHANGE_ELLIPTIC_CURVE
Enable to support ciphersuites with prefix TLS-ECDHE-RSA-WITH-
CONFIG_MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA¶
Enable ECDHE-ECDSA based ciphersuite modes
Found in: Component config > mbedTLS > TLS Key Exchange Methods > CONFIG_MBEDTLS_KEY_EXCHANGE_ELLIPTIC_CURVE
Enable to support ciphersuites with prefix TLS-ECDHE-RSA-WITH-
CONFIG_MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA¶
Enable ECDH-ECDSA based ciphersuite modes
Found in: Component config > mbedTLS > TLS Key Exchange Methods > CONFIG_MBEDTLS_KEY_EXCHANGE_ELLIPTIC_CURVE
Enable to support ciphersuites with prefix TLS-ECDHE-RSA-WITH-
CONFIG_MBEDTLS_KEY_EXCHANGE_ECDH_RSA¶
Enable ECDH-RSA based ciphersuite modes
Found in: Component config > mbedTLS > TLS Key Exchange Methods > CONFIG_MBEDTLS_KEY_EXCHANGE_ELLIPTIC_CURVE
Enable to support ciphersuites with prefix TLS-ECDHE-RSA-WITH-
CONFIG_MBEDTLS_KEY_EXCHANGE_ECJPAKE¶
Enable ECJPAKE based ciphersuite modes
Found in: Component config > mbedTLS > TLS Key Exchange Methods
Enable to support ciphersuites with prefix TLS-ECJPAKE-WITH-
CONFIG_MBEDTLS_SSL_RENEGOTIATION¶
Support TLS renegotiation
Found in: Component config > mbedTLS
The two main uses of renegotiation are (1) refresh keys on long-lived connections and (2) client authentication after the initial handshake. If you don’t need renegotiation, disabling it will save code size and reduce the possibility of abuse/vulnerability.
CONFIG_MBEDTLS_SSL_PROTO_SSL3¶
Legacy SSL 3.0 support
Found in: Component config > mbedTLS
Support the legacy SSL 3.0 protocol. Most servers will speak a newer TLS protocol these days.
CONFIG_MBEDTLS_SSL_PROTO_TLS1¶
Support TLS 1.0 protocol
Found in: Component config > mbedTLS
CONFIG_MBEDTLS_SSL_PROTO_TLS1_1¶
Support TLS 1.1 protocol
Found in: Component config > mbedTLS
CONFIG_MBEDTLS_SSL_PROTO_TLS1_2¶
Support TLS 1.2 protocol
Found in: Component config > mbedTLS
CONFIG_MBEDTLS_SSL_PROTO_DTLS¶
Support DTLS protocol (all versions)
Found in: Component config > mbedTLS
Requires TLS 1.1 to be enabled for DTLS 1.0 Requires TLS 1.2 to be enabled for DTLS 1.2
CONFIG_MBEDTLS_SSL_ALPN¶
Support ALPN (Application Layer Protocol Negotiation)
Found in: Component config > mbedTLS
Disabling this option will save some code size if it is not needed.
CONFIG_MBEDTLS_CLIENT_SSL_SESSION_TICKETS¶
TLS: Client Support for RFC 5077 SSL session tickets
Found in: Component config > mbedTLS
Client support for RFC 5077 session tickets. See mbedTLS documentation for more details. Disabling this option will save some code size.
CONFIG_MBEDTLS_SERVER_SSL_SESSION_TICKETS¶
TLS: Server Support for RFC 5077 SSL session tickets
Found in: Component config > mbedTLS
Server support for RFC 5077 session tickets. See mbedTLS documentation for more details. Disabling this option will save some code size.
Symmetric Ciphers¶
Contains:
CONFIG_MBEDTLS_AES_C¶
AES block cipher
Found in: Component config > mbedTLS > Symmetric Ciphers
CONFIG_MBEDTLS_CAMELLIA_C¶
Camellia block cipher
Found in: Component config > mbedTLS > Symmetric Ciphers
CONFIG_MBEDTLS_DES_C¶
DES block cipher (legacy, insecure)
Found in: Component config > mbedTLS > Symmetric Ciphers
Enables the DES block cipher to support 3DES-based TLS ciphersuites.
3DES is vulnerable to the Sweet32 attack and should only be enabled if absolutely necessary.
CONFIG_MBEDTLS_RC4_MODE¶
RC4 Stream Cipher (legacy, insecure)
Found in: Component config > mbedTLS > Symmetric Ciphers
ARCFOUR (RC4) stream cipher can be disabled entirely, enabled but not added to default ciphersuites, or enabled completely.
Please consider the security implications before enabling RC4.
- Available options:
Disabled (MBEDTLS_RC4_DISABLED)
Enabled, not in default ciphersuites (MBEDTLS_RC4_ENABLED_NO_DEFAULT)
Enabled (MBEDTLS_RC4_ENABLED)
CONFIG_MBEDTLS_BLOWFISH_C¶
Blowfish block cipher (read help)
Found in: Component config > mbedTLS > Symmetric Ciphers
Enables the Blowfish block cipher (not used for TLS sessions.)
The Blowfish cipher is not used for mbedTLS TLS sessions but can be used for other purposes. Read up on the limitations of Blowfish (including Sweet32) before enabling.
CONFIG_MBEDTLS_XTEA_C¶
XTEA block cipher
Found in: Component config > mbedTLS > Symmetric Ciphers
Enables the XTEA block cipher.
CONFIG_MBEDTLS_CCM_C¶
CCM (Counter with CBC-MAC) block cipher modes
Found in: Component config > mbedTLS > Symmetric Ciphers
Enable Counter with CBC-MAC (CCM) modes for AES and/or Camellia ciphers.
Disabling this option saves some code size.
CONFIG_MBEDTLS_GCM_C¶
GCM (Galois/Counter) block cipher modes
Found in: Component config > mbedTLS > Symmetric Ciphers
Enable Galois/Counter Mode for AES and/or Camellia ciphers.
This option is generally faster than CCM.
CONFIG_MBEDTLS_RIPEMD160_C¶
Enable RIPEMD-160 hash algorithm
Found in: Component config > mbedTLS
Enable the RIPEMD-160 hash algorithm.
Certificates¶
Contains:
CONFIG_MBEDTLS_PEM_PARSE_C¶
Read & Parse PEM formatted certificates
Found in: Component config > mbedTLS > Certificates
Enable decoding/parsing of PEM formatted certificates.
If your certificates are all in the simpler DER format, disabling this option will save some code size.
CONFIG_MBEDTLS_PEM_WRITE_C¶
Write PEM formatted certificates
Found in: Component config > mbedTLS > Certificates
Enable writing of PEM formatted certificates.
If writing certificate data only in DER format, disabling this option will save some code size.
CONFIG_MBEDTLS_X509_CRL_PARSE_C¶
X.509 CRL parsing
Found in: Component config > mbedTLS > Certificates
Support for parsing X.509 Certifificate Revocation Lists.
CONFIG_MBEDTLS_X509_CSR_PARSE_C¶
X.509 CSR parsing
Found in: Component config > mbedTLS > Certificates
Support for parsing X.509 Certifificate Signing Requests
CONFIG_MBEDTLS_ECP_C¶
Elliptic Curve Ciphers
Found in: Component config > mbedTLS
Contains:
CONFIG_MBEDTLS_ECDH_C¶
Elliptic Curve Diffie-Hellman (ECDH)
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ECP_C
Enable ECDH. Needed to use ECDHE-xxx TLS ciphersuites.
CONFIG_MBEDTLS_ECDSA_C¶
Elliptic Curve DSA
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ECP_C > CONFIG_MBEDTLS_ECDH_C
Enable ECDSA. Needed to use ECDSA-xxx TLS ciphersuites.
CONFIG_MBEDTLS_ECJPAKE_C¶
Elliptic curve J-PAKE
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ECP_C
Enable ECJPAKE. Needed to use ECJPAKE-xxx TLS ciphersuites.
CONFIG_MBEDTLS_ECP_DP_SECP192R1_ENABLED¶
Enable SECP192R1 curve
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ECP_C
Enable support for SECP192R1 Elliptic Curve.
CONFIG_MBEDTLS_ECP_DP_SECP224R1_ENABLED¶
Enable SECP224R1 curve
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ECP_C
Enable support for SECP224R1 Elliptic Curve.
CONFIG_MBEDTLS_ECP_DP_SECP256R1_ENABLED¶
Enable SECP256R1 curve
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ECP_C
Enable support for SECP256R1 Elliptic Curve.
CONFIG_MBEDTLS_ECP_DP_SECP384R1_ENABLED¶
Enable SECP384R1 curve
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ECP_C
Enable support for SECP384R1 Elliptic Curve.
CONFIG_MBEDTLS_ECP_DP_SECP521R1_ENABLED¶
Enable SECP521R1 curve
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ECP_C
Enable support for SECP521R1 Elliptic Curve.
CONFIG_MBEDTLS_ECP_DP_SECP192K1_ENABLED¶
Enable SECP192K1 curve
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ECP_C
Enable support for SECP192K1 Elliptic Curve.
CONFIG_MBEDTLS_ECP_DP_SECP224K1_ENABLED¶
Enable SECP224K1 curve
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ECP_C
Enable support for SECP224K1 Elliptic Curve.
CONFIG_MBEDTLS_ECP_DP_SECP256K1_ENABLED¶
Enable SECP256K1 curve
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ECP_C
Enable support for SECP256K1 Elliptic Curve.
CONFIG_MBEDTLS_ECP_DP_BP256R1_ENABLED¶
Enable BP256R1 curve
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ECP_C
support for DP Elliptic Curve.
CONFIG_MBEDTLS_ECP_DP_BP384R1_ENABLED¶
Enable BP384R1 curve
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ECP_C
support for DP Elliptic Curve.
CONFIG_MBEDTLS_ECP_DP_BP512R1_ENABLED¶
Enable BP512R1 curve
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ECP_C
support for DP Elliptic Curve.
CONFIG_MBEDTLS_ECP_DP_CURVE25519_ENABLED¶
Enable CURVE25519 curve
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ECP_C
Enable support for CURVE25519 Elliptic Curve.
CONFIG_MBEDTLS_ECP_NIST_OPTIM¶
NIST ‘modulo p’ optimisations
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_ECP_C
NIST ‘modulo p’ optimisations increase Elliptic Curve operation performance.
Disabling this option saves some code size.
# end of Elliptic Curve options
CONFIG_MBEDTLS_POLY1305_C¶
Poly1305 MAC algorithm
Found in: Component config > mbedTLS
Enable support for Poly1305 MAC algorithm.
CONFIG_MBEDTLS_CHACHA20_C¶
Chacha20 stream cipher
Found in: Component config > mbedTLS
Enable support for Chacha20 stream cipher.
CONFIG_MBEDTLS_CHACHAPOLY_C¶
ChaCha20-Poly1305 AEAD algorithm
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_CHACHA20_C
Enable support for ChaCha20-Poly1305 AEAD algorithm.
CONFIG_MBEDTLS_HKDF_C¶
HKDF algorithm (RFC 5869)
Found in: Component config > mbedTLS
Enable support for the Hashed Message Authentication Code (HMAC)-based key derivation function (HKDF).
CONFIG_MBEDTLS_THREADING_C¶
Enable the threading abstraction layer
Found in: Component config > mbedTLS
If you do intend to use contexts between threads, you will need to enable this layer to prevent race conditions.
CONFIG_MBEDTLS_THREADING_ALT¶
Enable threading alternate implementation
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_THREADING_C
Enable threading alt to allow your own alternate threading implementation.
CONFIG_MBEDTLS_THREADING_PTHREAD¶
Enable threading pthread implementation
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_THREADING_C
Enable the pthread wrapper layer for the threading layer.
CONFIG_MBEDTLS_SECURITY_RISKS¶
Show configurations with potential security risks
Found in: Component config > mbedTLS
Contains:
CONFIG_MBEDTLS_ALLOW_UNSUPPORTED_CRITICAL_EXT¶
X.509 CRT parsing with unsupported critical extensions
Found in: Component config > mbedTLS > CONFIG_MBEDTLS_SECURITY_RISKS
Allow the X.509 certificate parser to load certificates with unsupported critical extensions
LWIP¶
Contains:
CONFIG_LWIP_LOCAL_HOSTNAME¶
Local netif hostname
Found in: Component config > LWIP
The default name this device will report to other devices on the network. Could be updated at runtime with esp_netif_set_hostname()
CONFIG_LWIP_DNS_SUPPORT_MDNS_QUERIES¶
Enable mDNS queries in resolving host name
Found in: Component config > LWIP
If this feature is enabled, standard API such as gethostbyname support .local addresses by sending one shot multicast mDNS query
CONFIG_LWIP_L2_TO_L3_COPY¶
Enable copy between Layer2 and Layer3 packets
Found in: Component config > LWIP
If this feature is enabled, all traffic from layer2(WIFI Driver) will be copied to a new buffer before sending it to layer3(LWIP stack), freeing the layer2 buffer. Please be notified that the total layer2 receiving buffer is fixed and ESP32 currently supports 25 layer2 receiving buffer, when layer2 buffer runs out of memory, then the incoming packets will be dropped in hardware. The layer3 buffer is allocated from the heap, so the total layer3 receiving buffer depends on the available heap size, when heap runs out of memory, no copy will be sent to layer3 and packet will be dropped in layer2. Please make sure you fully understand the impact of this feature before enabling it.
CONFIG_LWIP_IRAM_OPTIMIZATION¶
Enable LWIP IRAM optimization
Found in: Component config > LWIP
If this feature is enabled, some functions relating to RX/TX in LWIP will be put into IRAM, it can improve UDP/TCP throughput by >10% for single core mode, it doesn’t help too much for dual core mode. On the other hand, it needs about 10KB IRAM for these optimizations.
If this feature is disabled, all lwip functions will be put into FLASH.
CONFIG_LWIP_TIMERS_ONDEMAND¶
Enable LWIP Timers on demand
Found in: Component config > LWIP
If this feature is enabled, IGMP and MLD6 timers will be activated only when joining groups or receiving QUERY packets.
This feature will reduce the power consumption for applications which do not use IGMP and MLD6.
CONFIG_LWIP_MAX_SOCKETS¶
Max number of open sockets
Found in: Component config > LWIP
Sockets take up a certain amount of memory, and allowing fewer sockets to be open at the same time conserves memory. Specify the maximum amount of sockets here. The valid value is from 1 to 16.
CONFIG_LWIP_USE_ONLY_LWIP_SELECT¶
Support LWIP socket select() only (DEPRECATED)
Found in: Component config > LWIP
This option is deprecated. Use VFS_SUPPORT_SELECT instead, which is the inverse of this option.
The virtual filesystem layer of select() redirects sockets to lwip_select() and non-socket file descriptors to their respective driver implementations. If this option is enabled then all calls of select() will be redirected to lwip_select(), therefore, select can be used for sockets only.
CONFIG_LWIP_SO_LINGER¶
Enable SO_LINGER processing
Found in: Component config > LWIP
Enabling this option allows SO_LINGER processing. l_onoff = 1,l_linger can set the timeout.
If l_linger=0, When a connection is closed, TCP will terminate the connection. This means that TCP will discard any data packets stored in the socket send buffer and send an RST to the peer.
If l_linger!=0,Then closesocket() calls to block the process until the remaining data packets has been sent or timed out.
CONFIG_LWIP_SO_REUSE¶
Enable SO_REUSEADDR option
Found in: Component config > LWIP
Enabling this option allows binding to a port which remains in TIME_WAIT.
CONFIG_LWIP_SO_REUSE_RXTOALL¶
SO_REUSEADDR copies broadcast/multicast to all matches
Found in: Component config > LWIP > CONFIG_LWIP_SO_REUSE
Enabling this option means that any incoming broadcast or multicast packet will be copied to all of the local sockets that it matches (may be more than one if SO_REUSEADDR is set on the socket.)
This increases memory overhead as the packets need to be copied, however they are only copied per matching socket. You can safely disable it if you don’t plan to receive broadcast or multicast traffic on more than one socket at a time.
CONFIG_LWIP_SO_RCVBUF¶
Enable SO_RCVBUF option
Found in: Component config > LWIP
Enabling this option allows checking for available data on a netconn.
CONFIG_LWIP_NETBUF_RECVINFO¶
Enable IP_PKTINFO option
Found in: Component config > LWIP
Enabling this option allows checking for the destination address of a received IPv4 Packet.
CONFIG_LWIP_IP4_FRAG¶
Enable fragment outgoing IP4 packets
Found in: Component config > LWIP
Enabling this option allows fragmenting outgoing IP4 packets if their size exceeds MTU.
CONFIG_LWIP_IP6_FRAG¶
Enable fragment outgoing IP6 packets
Found in: Component config > LWIP
Enabling this option allows fragmenting outgoing IP6 packets if their size exceeds MTU.
CONFIG_LWIP_IP4_REASSEMBLY¶
Enable reassembly incoming fragmented IP4 packets
Found in: Component config > LWIP
Enabling this option allows reassemblying incoming fragmented IP4 packets.
CONFIG_LWIP_IP6_REASSEMBLY¶
Enable reassembly incoming fragmented IP6 packets
Found in: Component config > LWIP
Enabling this option allows reassemblying incoming fragmented IP6 packets.
CONFIG_LWIP_IP_FORWARD¶
Enable IP forwarding
Found in: Component config > LWIP
Enabling this option allows packets forwarding across multiple interfaces.
CONFIG_LWIP_IPV4_NAPT¶
Enable NAT (new/experimental)
Found in: Component config > LWIP > CONFIG_LWIP_IP_FORWARD
Enabling this option allows Network Address and Port Translation.
CONFIG_LWIP_STATS¶
Enable LWIP statistics
Found in: Component config > LWIP
Enabling this option allows LWIP statistics
CONFIG_LWIP_ETHARP_TRUST_IP_MAC¶
Enable LWIP ARP trust
Found in: Component config > LWIP
Enabling this option allows ARP table to be updated.
If this option is enabled, the incoming IP packets cause the ARP table to be updated with the source MAC and IP addresses supplied in the packet. You may want to disable this if you do not trust LAN peers to have the correct addresses, or as a limited approach to attempt to handle spoofing. If disabled, lwIP will need to make a new ARP request if the peer is not already in the ARP table, adding a little latency. The peer *is* in the ARP table if it requested our address before. Also notice that this slows down input processing of every IP packet!
There are two known issues in real application if this feature is enabled: - The LAN peer may have bug to update the ARP table after the ARP entry is aged out. If the ARP entry on the LAN peer is aged out but failed to be updated, all IP packets sent from LWIP to the LAN peer will be dropped by LAN peer. - The LAN peer may not be trustful, the LAN peer may send IP packets to LWIP with two different MACs, but the same IP address. If this happens, the LWIP has problem to receive IP packets from LAN peer.
So the recommendation is to disable this option. Here the LAN peer means the other side to which the ESP station or soft-AP is connected.
CONFIG_LWIP_ESP_GRATUITOUS_ARP¶
Send gratuitous ARP periodically
Found in: Component config > LWIP
Enable this option allows to send gratuitous ARP periodically.
This option solve the compatibility issues.If the ARP table of the AP is old, and the AP doesn’t send ARP request to update it’s ARP table, this will lead to the STA sending IP packet fail. Thus we send gratuitous ARP periodically to let AP update it’s ARP table.
CONFIG_LWIP_GARP_TMR_INTERVAL¶
GARP timer interval(seconds)
Found in: Component config > LWIP > CONFIG_LWIP_ESP_GRATUITOUS_ARP
Set the timer interval for gratuitous ARP. The default value is 60s
CONFIG_LWIP_TCPIP_RECVMBOX_SIZE¶
TCPIP task receive mail box size
Found in: Component config > LWIP
Set TCPIP task receive mail box size. Generally bigger value means higher throughput but more memory. The value should be bigger than UDP/TCP mail box size.
CONFIG_LWIP_DHCP_DOES_ARP_CHECK¶
DHCP: Perform ARP check on any offered address
Found in: Component config > LWIP
Enabling this option performs a check (via ARP request) if the offered IP address is not already in use by another host on the network.
CONFIG_LWIP_DHCP_DISABLE_CLIENT_ID¶
DHCP: Disable Use of HW address as client identification
Found in: Component config > LWIP
This option could be used to disable DHCP client identification with its MAC address. (Client id is used by DHCP servers to uniquely identify clients and are included in the DHCP packets as an option 61) Set this option to “y” in order to exclude option 61 from DHCP packets.
CONFIG_LWIP_DHCP_RESTORE_LAST_IP¶
DHCP: Restore last IP obtained from DHCP server
Found in: Component config > LWIP
When this option is enabled, DHCP client tries to re-obtain last valid IP address obtained from DHCP server. Last valid DHCP configuration is stored in nvs and restored after reset/power-up. If IP is still available, there is no need for sending discovery message to DHCP server and save some time.
CONFIG_LWIP_DHCP_COARSE_TIMER_SECS¶
DHCP coarse timer interval(s)
Found in: Component config > LWIP
Set DHCP coarse interval in seconds. A higher value will be less precise but cost less power consumption.
DHCP server¶
Contains:
CONFIG_LWIP_DHCPS_LEASE_UNIT¶
Multiplier for lease time, in seconds
Found in: Component config > LWIP > DHCP server
The DHCP server is calculating lease time multiplying the sent and received times by this number of seconds per unit. The default is 60, that equals one minute.
CONFIG_LWIP_DHCPS_MAX_STATION_NUM¶
Maximum number of stations
Found in: Component config > LWIP > DHCP server
The maximum number of DHCP clients that are connected to the server. After this number is exceeded, DHCP server removes of the oldest device from it’s address pool, without notification.
CONFIG_LWIP_AUTOIP¶
Enable IPV4 Link-Local Addressing (AUTOIP)
Found in: Component config > LWIP
Enabling this option allows the device to self-assign an address in the 169.256/16 range if none is assigned statically or via DHCP.
See RFC 3927.
Contains:
CONFIG_LWIP_AUTOIP_TRIES¶
DHCP Probes before self-assigning IPv4 LL address
Found in: Component config > LWIP > CONFIG_LWIP_AUTOIP
DHCP client will send this many probes before self-assigning a link local address.
From LWIP help: “This can be set as low as 1 to get an AutoIP address very quickly, but you should be prepared to handle a changing IP address when DHCP overrides AutoIP.” (In the case of ESP-IDF, this means multiple SYSTEM_EVENT_STA_GOT_IP events.)
CONFIG_LWIP_AUTOIP_MAX_CONFLICTS¶
Max IP conflicts before rate limiting
Found in: Component config > LWIP > CONFIG_LWIP_AUTOIP
If the AUTOIP functionality detects this many IP conflicts while self-assigning an address, it will go into a rate limited mode.
CONFIG_LWIP_AUTOIP_RATE_LIMIT_INTERVAL¶
Rate limited interval (seconds)
Found in: Component config > LWIP > CONFIG_LWIP_AUTOIP
If rate limiting self-assignment requests, wait this long between each request.
CONFIG_LWIP_IPV6_AUTOCONFIG¶
Enable IPV6 stateless address autoconfiguration
Found in: Component config > LWIP
Enabling this option allows the devices to IPV6 stateless address autoconfiguration.
See RFC 4862.
CONFIG_LWIP_NETIF_LOOPBACK¶
Support per-interface loopback
Found in: Component config > LWIP
Enabling this option means that if a packet is sent with a destination address equal to the interface’s own IP address, it will “loop back” and be received by this interface.
Contains:
CONFIG_LWIP_LOOPBACK_MAX_PBUFS¶
Max queued loopback packets per interface
Found in: Component config > LWIP > CONFIG_LWIP_NETIF_LOOPBACK
Configure the maximum number of packets which can be queued for loopback on a given interface. Reducing this number may cause packets to be dropped, but will avoid filling memory with queued packet data.
TCP¶
Contains:
CONFIG_LWIP_TCP_ISN_HOOK¶
Enable TCP ISN Hook
Found in: Component config > LWIP > TCP
Enables custom TCP ISN hook to randomize initial sequence number in TCP connection. This is recommended as default lwIP implementation (tcp_next_iss) is not very strong, as it does not take into consideration any platform specific entropy source.
CONFIG_LWIP_MAX_ACTIVE_TCP¶
Maximum active TCP Connections
Found in: Component config > LWIP > TCP
The maximum number of simultaneously active TCP connections. The practical maximum limit is determined by available heap memory at runtime.
Changing this value by itself does not substantially change the memory usage of LWIP, except for preventing new TCP connections after the limit is reached.
CONFIG_LWIP_MAX_LISTENING_TCP¶
Maximum listening TCP Connections
Found in: Component config > LWIP > TCP
The maximum number of simultaneously listening TCP connections. The practical maximum limit is determined by available heap memory at runtime.
Changing this value by itself does not substantially change the memory usage of LWIP, except for preventing new listening TCP connections after the limit is reached.
CONFIG_LWIP_TCP_HIGH_SPEED_RETRANSMISSION¶
TCP high speed retransmissions
Found in: Component config > LWIP > TCP
Speed up the TCP retransmission interval. If disabled, it is recommended to change the number of SYN retransmissions to 6, and TCP initial rto time to 3000.
CONFIG_LWIP_TCP_MAXRTX¶
Maximum number of retransmissions of data segments
Found in: Component config > LWIP > TCP
Set maximum number of retransmissions of data segments.
CONFIG_LWIP_TCP_SYNMAXRTX¶
Maximum number of retransmissions of SYN segments
Found in: Component config > LWIP > TCP
Set maximum number of retransmissions of SYN segments.
CONFIG_LWIP_TCP_MSS¶
Maximum Segment Size (MSS)
Found in: Component config > LWIP > TCP
Set maximum segment size for TCP transmission.
Can be set lower to save RAM, the default value 1460(ipv4)/1440(ipv6) will give best throughput. IPv4 TCP_MSS Range: 576 <= TCP_MSS <= 1460 IPv6 TCP_MSS Range: 1220<= TCP_mSS <= 1440
CONFIG_LWIP_TCP_TMR_INTERVAL¶
TCP timer interval(ms)
Found in: Component config > LWIP > TCP
Set TCP timer interval in milliseconds.
Can be used to speed connections on bad networks. A lower value will redeliver unacked packets faster.
CONFIG_LWIP_TCP_MSL¶
Maximum segment lifetime (MSL)
Found in: Component config > LWIP > TCP
Set maximum segment lifetime in milliseconds.
CONFIG_LWIP_TCP_FIN_WAIT_TIMEOUT¶
Maximum FIN segment lifetime
Found in: Component config > LWIP > TCP
Set maximum segment lifetime in milliseconds.
CONFIG_LWIP_TCP_SND_BUF_DEFAULT¶
Default send buffer size
Found in: Component config > LWIP > TCP
Set default send buffer size for new TCP sockets.
Per-socket send buffer size can be changed at runtime with lwip_setsockopt(s, TCP_SNDBUF, …).
This value must be at least 2x the MSS size, and the default is 4x the default MSS size.
Setting a smaller default SNDBUF size can save some RAM, but will decrease performance.
CONFIG_LWIP_TCP_WND_DEFAULT¶
Default receive window size
Found in: Component config > LWIP > TCP
Set default TCP receive window size for new TCP sockets.
Per-socket receive window size can be changed at runtime with lwip_setsockopt(s, TCP_WINDOW, …).
Setting a smaller default receive window size can save some RAM, but will significantly decrease performance.
CONFIG_LWIP_TCP_RECVMBOX_SIZE¶
Default TCP receive mail box size
Found in: Component config > LWIP > TCP
Set TCP receive mail box size. Generally bigger value means higher throughput but more memory. The recommended value is: LWIP_TCP_WND_DEFAULT/TCP_MSS + 2, e.g. if LWIP_TCP_WND_DEFAULT=14360, TCP_MSS=1436, then the recommended receive mail box size is (14360/1436 + 2) = 12.
TCP receive mail box is a per socket mail box, when the application receives packets from TCP socket, LWIP core firstly posts the packets to TCP receive mail box and the application then fetches the packets from mail box. It means LWIP can caches maximum LWIP_TCP_RECCVMBOX_SIZE packets for each TCP socket, so the maximum possible cached TCP packets for all TCP sockets is LWIP_TCP_RECCVMBOX_SIZE multiples the maximum TCP socket number. In other words, the bigger LWIP_TCP_RECVMBOX_SIZE means more memory. On the other hand, if the receiv mail box is too small, the mail box may be full. If the mail box is full, the LWIP drops the packets. So generally we need to make sure the TCP receive mail box is big enough to avoid packet drop between LWIP core and application.
CONFIG_LWIP_TCP_QUEUE_OOSEQ¶
Queue incoming out-of-order segments
Found in: Component config > LWIP > TCP
Queue incoming out-of-order segments for later use.
Disable this option to save some RAM during TCP sessions, at the expense of increased retransmissions if segments arrive out of order.
CONFIG_LWIP_TCP_SACK_OUT¶
Support sending selective acknowledgements
Found in: Component config > LWIP > TCP
TCP will support sending selective acknowledgements (SACKs).
CONFIG_LWIP_TCP_KEEP_CONNECTION_WHEN_IP_CHANGES¶
Keep TCP connections when IP changed
Found in: Component config > LWIP > TCP
This option is enabled when the following scenario happen: network dropped and reconnected, IP changes is like: 192.168.0.2->0.0.0.0->192.168.0.2
Disable this option to keep consistent with the original LWIP code behavior.
CONFIG_LWIP_TCP_OVERSIZE¶
Pre-allocate transmit PBUF size
Found in: Component config > LWIP > TCP
Allows enabling “oversize” allocation of TCP transmission pbufs ahead of time, which can reduce the length of pbuf chains used for transmission.
This will not make a difference to sockets where Nagle’s algorithm is disabled.
Default value of MSS is fine for most applications, 25% MSS may save some RAM when only transmitting small amounts of data. Disabled will have worst performance and fragmentation characteristics, but uses least RAM overall.
- Available options:
MSS (LWIP_TCP_OVERSIZE_MSS)
25% MSS (LWIP_TCP_OVERSIZE_QUARTER_MSS)
Disabled (LWIP_TCP_OVERSIZE_DISABLE)
CONFIG_LWIP_WND_SCALE¶
Support TCP window scale
Found in: Component config > LWIP > TCP
Enable this feature to support TCP window scaling.
CONFIG_LWIP_TCP_RCV_SCALE¶
Set TCP receiving window scaling factor
Found in: Component config > LWIP > TCP > CONFIG_LWIP_WND_SCALE
Enable this feature to support TCP window scaling.
CONFIG_LWIP_TCP_RTO_TIME¶
Default TCP rto time
Found in: Component config > LWIP > TCP
Set default TCP rto time for a reasonable initial rto. In bad network environment, recommend set value of rto time to 1500.
UDP¶
Contains:
CONFIG_LWIP_MAX_UDP_PCBS¶
Maximum active UDP control blocks
Found in: Component config > LWIP > UDP
The maximum number of active UDP “connections” (ie UDP sockets sending/receiving data). The practical maximum limit is determined by available heap memory at runtime.
CONFIG_LWIP_UDP_RECVMBOX_SIZE¶
Default UDP receive mail box size
Found in: Component config > LWIP > UDP
Set UDP receive mail box size. The recommended value is 6.
UDP receive mail box is a per socket mail box, when the application receives packets from UDP socket, LWIP core firstly posts the packets to UDP receive mail box and the application then fetches the packets from mail box. It means LWIP can caches maximum UDP_RECCVMBOX_SIZE packets for each UDP socket, so the maximum possible cached UDP packets for all UDP sockets is UDP_RECCVMBOX_SIZE multiples the maximum UDP socket number. In other words, the bigger UDP_RECVMBOX_SIZE means more memory. On the other hand, if the receiv mail box is too small, the mail box may be full. If the mail box is full, the LWIP drops the packets. So generally we need to make sure the UDP receive mail box is big enough to avoid packet drop between LWIP core and application.
CONFIG_LWIP_TCPIP_TASK_STACK_SIZE¶
TCP/IP Task Stack Size
Found in: Component config > LWIP
Configure TCP/IP task stack size, used by LWIP to process multi-threaded TCP/IP operations. Setting this stack too small will result in stack overflow crashes.
CONFIG_LWIP_TCPIP_TASK_AFFINITY¶
TCP/IP task affinity
Found in: Component config > LWIP
Allows setting LwIP tasks affinity, i.e. whether the task is pinned to CPU0, pinned to CPU1, or allowed to run on any CPU. Currently this applies to “TCP/IP” task and “Ping” task.
- Available options:
No affinity (LWIP_TCPIP_TASK_AFFINITY_NO_AFFINITY)
CPU0 (LWIP_TCPIP_TASK_AFFINITY_CPU0)
CPU1 (LWIP_TCPIP_TASK_AFFINITY_CPU1)
CONFIG_LWIP_PPP_SUPPORT¶
Enable PPP support (new/experimental)
Found in: Component config > LWIP
Enable PPP stack. Now only PPP over serial is possible.
PPP over serial support is experimental and unsupported.
Contains:
CONFIG_LWIP_PPP_ENABLE_IPV6¶
Enable IPV6 support for PPP connections (IPV6CP)
Found in: Component config > LWIP > CONFIG_LWIP_PPP_SUPPORT
Enable IPV6 support in PPP for the local link between the DTE (processor) and DCE (modem). There are some modems which do not support the IPV6 addressing in the local link. If they are requested for IPV6CP negotiation, they may time out. This would in turn fail the configuration for the whole link. If your modem is not responding correctly to PPP Phase Network, try to disable IPV6 support.
CONFIG_LWIP_IPV6_MEMP_NUM_ND6_QUEUE¶
Max number of IPv6 packets to queue during MAC resolution
Found in: Component config > LWIP
Config max number of IPv6 packets to queue during MAC resolution.
CONFIG_LWIP_IPV6_ND6_NUM_NEIGHBORS¶
Max number of entries in IPv6 neighbor cache
Found in: Component config > LWIP
Config max number of entries in IPv6 neighbor cache
CONFIG_LWIP_PPP_NOTIFY_PHASE_SUPPORT¶
Enable Notify Phase Callback
Found in: Component config > LWIP
Enable to set a callback which is called on change of the internal PPP state machine.
CONFIG_LWIP_PPP_PAP_SUPPORT¶
Enable PAP support
Found in: Component config > LWIP
Enable Password Authentication Protocol (PAP) support
CONFIG_LWIP_PPP_CHAP_SUPPORT¶
Enable CHAP support
Found in: Component config > LWIP
Enable Challenge Handshake Authentication Protocol (CHAP) support
CONFIG_LWIP_PPP_MSCHAP_SUPPORT¶
Enable MSCHAP support
Found in: Component config > LWIP
Enable Microsoft version of the Challenge-Handshake Authentication Protocol (MSCHAP) support
CONFIG_LWIP_PPP_MPPE_SUPPORT¶
Enable MPPE support
Found in: Component config > LWIP
Enable Microsoft Point-to-Point Encryption (MPPE) support
CONFIG_LWIP_PPP_DEBUG_ON¶
ICMP¶
Contains:
CONFIG_LWIP_MULTICAST_PING¶
Respond to multicast pings
Found in: Component config > LWIP > ICMP
CONFIG_LWIP_BROADCAST_PING¶
Respond to broadcast pings
Found in: Component config > LWIP > ICMP
LWIP RAW API¶
Contains:
CONFIG_LWIP_MAX_RAW_PCBS¶
Maximum LWIP RAW PCBs
Found in: Component config > LWIP > LWIP RAW API
The maximum number of simultaneously active LWIP RAW protocol control blocks. The practical maximum limit is determined by available heap memory at runtime.
SNTP¶
Contains:
CONFIG_LWIP_DHCP_MAX_NTP_SERVERS¶
Maximum number of NTP servers
Found in: Component config > LWIP > SNTP
Set maximum number of NTP servers used by LwIP SNTP module. First argument of sntp_setserver/sntp_setservername functions is limited to this value.
CONFIG_LWIP_SNTP_UPDATE_DELAY¶
Request interval to update time (ms)
Found in: Component config > LWIP > SNTP
This option allows you to set the time update period via SNTP. Default is 1 hour. Must not be below 15 seconds by specification. (SNTPv4 RFC 4330 enforces a minimum update time of 15 seconds).
CONFIG_LWIP_ESP_LWIP_ASSERT¶
Enable LWIP ASSERT checks
Found in: Component config > LWIP
Enable this option allows lwip to check assert. It is recommended to keep it open, do not close it.
ESP-MQTT Configurations¶
Contains:
CONFIG_MQTT_PROTOCOL_311¶
Enable MQTT protocol 3.1.1
Found in: Component config > ESP-MQTT Configurations
If not, this library will use MQTT protocol 3.1
CONFIG_MQTT_TRANSPORT_SSL¶
Enable MQTT over SSL
Found in: Component config > ESP-MQTT Configurations
Enable MQTT transport over SSL with mbedtls
CONFIG_MQTT_TRANSPORT_WEBSOCKET¶
Enable MQTT over Websocket
Found in: Component config > ESP-MQTT Configurations
Enable MQTT transport over Websocket.
CONFIG_MQTT_TRANSPORT_WEBSOCKET_SECURE¶
Enable MQTT over Websocket Secure
Found in: Component config > ESP-MQTT Configurations > CONFIG_MQTT_TRANSPORT_WEBSOCKET
Enable MQTT transport over Websocket Secure.
CONFIG_MQTT_USE_CUSTOM_CONFIG¶
MQTT Using custom configurations
Found in: Component config > ESP-MQTT Configurations
Custom MQTT configurations.
CONFIG_MQTT_TCP_DEFAULT_PORT¶
Default MQTT over TCP port
Found in: Component config > ESP-MQTT Configurations > CONFIG_MQTT_USE_CUSTOM_CONFIG
Default MQTT over TCP port
CONFIG_MQTT_SSL_DEFAULT_PORT¶
Default MQTT over SSL port
Found in: Component config > ESP-MQTT Configurations > CONFIG_MQTT_USE_CUSTOM_CONFIG
Default MQTT over SSL port
CONFIG_MQTT_WS_DEFAULT_PORT¶
Default MQTT over Websocket port
Found in: Component config > ESP-MQTT Configurations > CONFIG_MQTT_USE_CUSTOM_CONFIG
Default MQTT over Websocket port
CONFIG_MQTT_WSS_DEFAULT_PORT¶
Default MQTT over Websocket Secure port
Found in: Component config > ESP-MQTT Configurations > CONFIG_MQTT_USE_CUSTOM_CONFIG
Default MQTT over Websocket Secure port
CONFIG_MQTT_BUFFER_SIZE¶
Default MQTT Buffer Size
Found in: Component config > ESP-MQTT Configurations > CONFIG_MQTT_USE_CUSTOM_CONFIG
This buffer size using for both transmit and receive
CONFIG_MQTT_TASK_STACK_SIZE¶
MQTT task stack size
Found in: Component config > ESP-MQTT Configurations > CONFIG_MQTT_USE_CUSTOM_CONFIG
MQTT task stack size
CONFIG_MQTT_DISABLE_API_LOCKS¶
Disable API locks
Found in: Component config > ESP-MQTT Configurations > CONFIG_MQTT_USE_CUSTOM_CONFIG
Default config employs API locks to protect internal structures. It is possible to disable these locks if the user code doesn’t access MQTT API from multiple concurrent tasks
CONFIG_MQTT_TASK_PRIORITY¶
MQTT task priority
Found in: Component config > ESP-MQTT Configurations > CONFIG_MQTT_USE_CUSTOM_CONFIG
MQTT task priority. Higher number denotes higher priority.
CONFIG_MQTT_TASK_CORE_SELECTION_ENABLED¶
Enable MQTT task core selection
Found in: Component config > ESP-MQTT Configurations
This will enable core selection
CONFIG_MQTT_TASK_CORE_SELECTION¶
Core to use ?
Found in: Component config > ESP-MQTT Configurations > CONFIG_MQTT_TASK_CORE_SELECTION_ENABLED
- Available options:
Core 0 (MQTT_USE_CORE_0)
Core 1 (MQTT_USE_CORE_1)
CONFIG_MQTT_CUSTOM_OUTBOX¶
Enable custom outbox implementation
Found in: Component config > ESP-MQTT Configurations
Set to true if a specific implementation of message outbox is needed (e.g. persistant outbox in NVM or similar).
Wi-Fi¶
Contains:
CONFIG_ESP32_WIFI_STATIC_RX_BUFFER_NUM¶
Max number of WiFi static RX buffers
Found in: Component config > Wi-Fi
Set the number of WiFi static RX buffers. Each buffer takes approximately 1.6KB of RAM. The static rx buffers are allocated when esp_wifi_init is called, they are not freed until esp_wifi_deinit is called.
WiFi hardware use these buffers to receive all 802.11 frames. A higher number may allow higher throughput but increases memory use. If ESP32_WIFI_AMPDU_RX_ENABLED is enabled, this value is recommended to set equal or bigger than ESP32_WIFI_RX_BA_WIN in order to achieve better throughput and compatibility with both stations and APs.
CONFIG_ESP32_WIFI_DYNAMIC_RX_BUFFER_NUM¶
Max number of WiFi dynamic RX buffers
Found in: Component config > Wi-Fi
Set the number of WiFi dynamic RX buffers, 0 means unlimited RX buffers will be allocated (provided sufficient free RAM). The size of each dynamic RX buffer depends on the size of the received data frame.
For each received data frame, the WiFi driver makes a copy to an RX buffer and then delivers it to the high layer TCP/IP stack. The dynamic RX buffer is freed after the higher layer has successfully received the data frame.
For some applications, WiFi data frames may be received faster than the application can process them. In these cases we may run out of memory if RX buffer number is unlimited (0).
If a dynamic RX buffer limit is set, it should be at least the number of static RX buffers.
CONFIG_ESP32_WIFI_TX_BUFFER¶
Type of WiFi TX buffers
Found in: Component config > Wi-Fi
Select type of WiFi TX buffers:
If “Static” is selected, WiFi TX buffers are allocated when WiFi is initialized and released when WiFi is de-initialized. The size of each static TX buffer is fixed to about 1.6KB.
If “Dynamic” is selected, each WiFi TX buffer is allocated as needed when a data frame is delivered to the Wifi driver from the TCP/IP stack. The buffer is freed after the data frame has been sent by the WiFi driver. The size of each dynamic TX buffer depends on the length of each data frame sent by the TCP/IP layer.
If PSRAM is enabled, “Static” should be selected to guarantee enough WiFi TX buffers. If PSRAM is disabled, “Dynamic” should be selected to improve the utilization of RAM.
- Available options:
Static (ESP32_WIFI_STATIC_TX_BUFFER)
Dynamic (ESP32_WIFI_DYNAMIC_TX_BUFFER)
CONFIG_ESP32_WIFI_STATIC_TX_BUFFER_NUM¶
Max number of WiFi static TX buffers
Found in: Component config > Wi-Fi
Set the number of WiFi static TX buffers. Each buffer takes approximately 1.6KB of RAM. The static RX buffers are allocated when esp_wifi_init() is called, they are not released until esp_wifi_deinit() is called.
For each transmitted data frame from the higher layer TCP/IP stack, the WiFi driver makes a copy of it in a TX buffer. For some applications especially UDP applications, the upper layer can deliver frames faster than WiFi layer can transmit. In these cases, we may run out of TX buffers.
CONFIG_ESP32_WIFI_CACHE_TX_BUFFER_NUM¶
Max number of WiFi cache TX buffers
Found in: Component config > Wi-Fi
Set the number of WiFi cache TX buffer number.
For each TX packet from uplayer, such as LWIP etc, WiFi driver needs to allocate a static TX buffer and makes a copy of uplayer packet. If WiFi driver fails to allocate the static TX buffer, it caches the uplayer packets to a dedicated buffer queue, this option is used to configure the size of the cached TX queue.
CONFIG_ESP32_WIFI_DYNAMIC_TX_BUFFER_NUM¶
Max number of WiFi dynamic TX buffers
Found in: Component config > Wi-Fi
Set the number of WiFi dynamic TX buffers. The size of each dynamic TX buffer is not fixed, it depends on the size of each transmitted data frame.
For each transmitted frame from the higher layer TCP/IP stack, the WiFi driver makes a copy of it in a TX buffer. For some applications, especially UDP applications, the upper layer can deliver frames faster than WiFi layer can transmit. In these cases, we may run out of TX buffers.
CONFIG_ESP32_WIFI_CSI_ENABLED¶
WiFi CSI(Channel State Information)
Found in: Component config > Wi-Fi
Select this option to enable CSI(Channel State Information) feature. CSI takes about CONFIG_ESP32_WIFI_STATIC_RX_BUFFER_NUM KB of RAM. If CSI is not used, it is better to disable this feature in order to save memory.
CONFIG_ESP32_WIFI_AMPDU_TX_ENABLED¶
CONFIG_ESP32_WIFI_TX_BA_WIN¶
WiFi AMPDU TX BA window size
Found in: Component config > Wi-Fi > CONFIG_ESP32_WIFI_AMPDU_TX_ENABLED
Set the size of WiFi Block Ack TX window. Generally a bigger value means higher throughput but more memory. Most of time we should NOT change the default value unless special reason, e.g. test the maximum UDP TX throughput with iperf etc. For iperf test in shieldbox, the recommended value is 9~12.
CONFIG_ESP32_WIFI_AMPDU_RX_ENABLED¶
CONFIG_ESP32_WIFI_RX_BA_WIN¶
WiFi AMPDU RX BA window size
Found in: Component config > Wi-Fi > CONFIG_ESP32_WIFI_AMPDU_RX_ENABLED
Set the size of WiFi Block Ack RX window. Generally a bigger value means higher throughput and better compatibility but more memory. Most of time we should NOT change the default value unless special reason, e.g. test the maximum UDP RX throughput with iperf etc. For iperf test in shieldbox, the recommended value is 9~12. If PSRAM is used and WiFi memory is prefered to allocat in PSRAM first, the default and minimum value should be 16 to achieve better throughput and compatibility with both stations and APs.
CONFIG_ESP32_WIFI_NVS_ENABLED¶
CONFIG_ESP32_WIFI_TASK_CORE_ID¶
WiFi Task Core ID
Found in: Component config > Wi-Fi
Pinned WiFi task to core 0 or core 1.
- Available options:
Core 0 (ESP32_WIFI_TASK_PINNED_TO_CORE_0)
Core 1 (ESP32_WIFI_TASK_PINNED_TO_CORE_1)
CONFIG_ESP32_WIFI_SOFTAP_BEACON_MAX_LEN¶
Max length of WiFi SoftAP Beacon
Found in: Component config > Wi-Fi
ESP-MESH utilizes beacon frames to detect and resolve root node conflicts (see documentation). However the default length of a beacon frame can simultaneously hold only five root node identifier structures, meaning that a root node conflict of up to five nodes can be detected at one time. In the occurence of more root nodes conflict involving more than five root nodes, the conflict resolution process will detect five of the root nodes, resolve the conflict, and re-detect more root nodes. This process will repeat until all root node conflicts are resolved. However this process can generally take a very long time.
To counter this situation, the beacon frame length can be increased such that more root nodes can be detected simultaneously. Each additional root node will require 36 bytes and should be added ontop of the default beacon frame length of 752 bytes. For example, if you want to detect 10 root nodes simultaneously, you need to set the beacon frame length as 932 (752+36*5).
Setting a longer beacon length also assists with debugging as the conflicting root nodes can be identified more quickly.
CONFIG_ESP32_WIFI_MGMT_SBUF_NUM¶
WiFi mgmt short buffer number
Found in: Component config > Wi-Fi
Set the number of WiFi management short buffer.
CONFIG_ESP32_WIFI_DEBUG_LOG_ENABLE¶
Enable WiFi debug log
Found in: Component config > Wi-Fi
Select this option to enable WiFi debug log
CONFIG_ESP32_WIFI_DEBUG_LOG_LEVEL¶
WiFi debug log level
Found in: Component config > Wi-Fi > CONFIG_ESP32_WIFI_DEBUG_LOG_ENABLE
The WiFi log is divided into the following levels: ERROR,WARNING,INFO,DEBUG,VERBOSE. The ERROR,WARNING,INFO levels are enabled by default, and the DEBUG,VERBOSE levels can be enabled here.
- Available options:
WiFi Debug Log Debug (ESP32_WIFI_DEBUG_LOG_DEBUG)
WiFi Debug Log Verbose (ESP32_WIFI_DEBUG_LOG_VERBOSE)
CONFIG_ESP32_WIFI_DEBUG_LOG_MODULE¶
WiFi debug log module
Found in: Component config > Wi-Fi > CONFIG_ESP32_WIFI_DEBUG_LOG_ENABLE
The WiFi log module contains three parts: WIFI,COEX,MESH. The WIFI module indicates the logs related to WiFi, the COEX module indicates the logs related to WiFi and BT(or BLE) coexist, the MESH module indicates the logs related to Mesh. When ESP32_WIFI_LOG_MODULE_ALL is enabled, all modules are selected.
- Available options:
WiFi Debug Log Module All (ESP32_WIFI_DEBUG_LOG_MODULE_ALL)
WiFi Debug Log Module WiFi (ESP32_WIFI_DEBUG_LOG_MODULE_WIFI)
WiFi Debug Log Module Coex (ESP32_WIFI_DEBUG_LOG_MODULE_COEX)
WiFi Debug Log Module Mesh (ESP32_WIFI_DEBUG_LOG_MODULE_MESH)
CONFIG_ESP32_WIFI_DEBUG_LOG_SUBMODULE¶
WiFi debug log submodule
Found in: Component config > Wi-Fi > CONFIG_ESP32_WIFI_DEBUG_LOG_ENABLE
Enable this option to set the WiFi debug log submodule. Currently the log submodule contains the following parts: INIT,IOCTL,CONN,SCAN. The INIT submodule indicates the initialization process.The IOCTL submodule indicates the API calling process. The CONN submodule indicates the connecting process.The SCAN submodule indicates the scaning process.
CONFIG_ESP32_WIFI_DEBUG_LOG_SUBMODULE_ALL¶
WiFi Debug Log Submodule All
Found in: Component config > Wi-Fi > CONFIG_ESP32_WIFI_DEBUG_LOG_ENABLE > CONFIG_ESP32_WIFI_DEBUG_LOG_SUBMODULE
When this option is enabled, all debug submodules are selected.
CONFIG_ESP32_WIFI_DEBUG_LOG_SUBMODULE_INIT¶
WiFi Debug Log Submodule Init
Found in: Component config > Wi-Fi > CONFIG_ESP32_WIFI_DEBUG_LOG_ENABLE > CONFIG_ESP32_WIFI_DEBUG_LOG_SUBMODULE
CONFIG_ESP32_WIFI_DEBUG_LOG_SUBMODULE_IOCTL¶
WiFi Debug Log Submodule Ioctl
Found in: Component config > Wi-Fi > CONFIG_ESP32_WIFI_DEBUG_LOG_ENABLE > CONFIG_ESP32_WIFI_DEBUG_LOG_SUBMODULE
CONFIG_ESP32_WIFI_DEBUG_LOG_SUBMODULE_CONN¶
WiFi Debug Log Submodule Conn
Found in: Component config > Wi-Fi > CONFIG_ESP32_WIFI_DEBUG_LOG_ENABLE > CONFIG_ESP32_WIFI_DEBUG_LOG_SUBMODULE
CONFIG_ESP32_WIFI_DEBUG_LOG_SUBMODULE_SCAN¶
WiFi Debug Log Submodule Scan
Found in: Component config > Wi-Fi > CONFIG_ESP32_WIFI_DEBUG_LOG_ENABLE > CONFIG_ESP32_WIFI_DEBUG_LOG_SUBMODULE
CONFIG_ESP32_WIFI_IRAM_OPT¶
WiFi IRAM speed optimization
Found in: Component config > Wi-Fi
Select this option to place frequently called Wi-Fi library functions in IRAM. When this option is disabled, more than 10Kbytes of IRAM memory will be saved but Wi-Fi throughput will be reduced.
CONFIG_ESP32_WIFI_RX_IRAM_OPT¶
WiFi RX IRAM speed optimization
Found in: Component config > Wi-Fi
Select this option to place frequently called Wi-Fi library RX functions in IRAM. When this option is disabled, more than 17Kbytes of IRAM memory will be saved but Wi-Fi performance will be reduced.
CONFIG_ESP32_WIFI_ENABLE_WPA3_SAE¶
Enable WPA3-Personal
Found in: Component config > Wi-Fi
Select this option to allow the device to establish a WPA3-Personal connection with eligible AP’s. PMF (Protected Management Frames) is a prerequisite feature for a WPA3 connection, it needs to be explicitly configured before attempting connection. Please refer to the Wi-Fi Driver API Guide for details.
PHY¶
Contains:
CONFIG_ESP32_PHY_CALIBRATION_AND_DATA_STORAGE¶
Store phy calibration data in NVS
Found in: Component config > PHY
If this option is enabled, NVS will be initialized and calibration data will be loaded from there. PHY calibration will be skipped on deep sleep wakeup. If calibration data is not found, full calibration will be performed and stored in NVS. Normally, only partial calibration will be performed. If this option is disabled, full calibration will be performed.
If it’s easy that your board calibrate bad data, choose ‘n’. Two cases for example, you should choose ‘n’: 1.If your board is easy to be booted up with antenna disconnected. 2.Because of your board design, each time when you do calibration, the result are too unstable. If unsure, choose ‘y’.
CONFIG_ESP32_PHY_INIT_DATA_IN_PARTITION¶
Use a partition to store PHY init data
Found in: Component config > PHY
If enabled, PHY init data will be loaded from a partition. When using a custom partition table, make sure that PHY data partition is included (type: ‘data’, subtype: ‘phy’). With default partition tables, this is done automatically. If PHY init data is stored in a partition, it has to be flashed there, otherwise runtime error will occur.
If this option is not enabled, PHY init data will be embedded into the application binary.
If unsure, choose ‘n’.
Contains:
CONFIG_ESP32_PHY_DEFAULT_INIT_IF_INVALID¶
Reset default PHY init data if invalid
Found in: Component config > PHY > CONFIG_ESP32_PHY_INIT_DATA_IN_PARTITION
If enabled, PHY init data will be restored to default if it cannot be verified successfully to avoid endless bootloops.
If unsure, choose ‘n’.
CONFIG_ESP32_SUPPORT_MULTIPLE_PHY_INIT_DATA_BIN¶
Support multiple PHY init data bin
Found in: Component config > PHY > CONFIG_ESP32_PHY_INIT_DATA_IN_PARTITION
If enabled, the corresponding PHY init data type can be automatically switched according to the country code. China’s PHY init data bin is used by default. Can be modified by country information in API esp_wifi_set_country(). The priority of switching the PHY init data type is: 1. Country configured by API esp_wifi_set_country() and the parameter policy is WIFI_COUNTRY_POLICY_MANUAL. 2. Country notified by the connected AP. 3. Country configured by API esp_wifi_set_country() and the parameter policy is WIFI_COUNTRY_POLICY_AUTO.
CONFIG_ESP32_PHY_INIT_DATA_ERROR¶
Terminate operation when PHY init data error
Found in: Component config > PHY > CONFIG_ESP32_PHY_INIT_DATA_IN_PARTITION > CONFIG_ESP32_SUPPORT_MULTIPLE_PHY_INIT_DATA_BIN
If enabled, when an error occurs while the PHY init data is updated, the program will terminate and restart. If not enabled, the PHY init data will not be updated when an error occurs.
CONFIG_ESP32_PHY_MAX_WIFI_TX_POWER¶
Max WiFi TX power (dBm)
Found in: Component config > PHY
Set maximum transmit power for WiFi radio. Actual transmit power for high data rates may be lower than this setting.
SPI Flash driver¶
Contains:
CONFIG_SPI_FLASH_VERIFY_WRITE¶
Verify SPI flash writes
Found in: Component config > SPI Flash driver
If this option is enabled, any time SPI flash is written then the data will be read back and verified. This can catch hardware problems with SPI flash, or flash which was not erased before verification.
CONFIG_SPI_FLASH_LOG_FAILED_WRITE¶
Log errors if verification fails
Found in: Component config > SPI Flash driver > CONFIG_SPI_FLASH_VERIFY_WRITE
If this option is enabled, if SPI flash write verification fails then a log error line will be written with the address, expected & actual values. This can be useful when debugging hardware SPI flash problems.
CONFIG_SPI_FLASH_WARN_SETTING_ZERO_TO_ONE¶
Log warning if writing zero bits to ones
Found in: Component config > SPI Flash driver > CONFIG_SPI_FLASH_VERIFY_WRITE
If this option is enabled, any SPI flash write which tries to set zero bits in the flash to ones will log a warning. Such writes will not result in the requested data appearing identically in flash once written, as SPI NOR flash can only set bits to one when an entire sector is erased. After erasing, individual bits can only be written from one to zero.
Note that some software (such as SPIFFS) which is aware of SPI NOR flash may write one bits as an optimisation, relying on the data in flash becoming a bitwise AND of the new data and any existing data. Such software will log spurious warnings if this option is enabled.
CONFIG_SPI_FLASH_ENABLE_COUNTERS¶
Enable operation counters
Found in: Component config > SPI Flash driver
This option enables the following APIs:
spi_flash_reset_counters
spi_flash_dump_counters
spi_flash_get_counters
These APIs may be used to collect performance data for spi_flash APIs and to help understand behaviour of libraries which use SPI flash.
CONFIG_SPI_FLASH_ROM_DRIVER_PATCH¶
Enable SPI flash ROM driver patched functions
Found in: Component config > SPI Flash driver
Enable this flag to use patched versions of SPI flash ROM driver functions. This option should be enabled, if any one of the following is true: (1) need to write to flash on ESP32-D2WD; (2) main SPI flash is connected to non-default pins; (3) main SPI flash chip is manufactured by ISSI.
CONFIG_SPI_FLASH_DANGEROUS_WRITE¶
Writing to dangerous flash regions
Found in: Component config > SPI Flash driver
SPI flash APIs can optionally abort or return a failure code if erasing or writing addresses that fall at the beginning of flash (covering the bootloader and partition table) or that overlap the app partition that contains the running app.
It is not recommended to ever write to these regions from an IDF app, and this check prevents logic errors or corrupted firmware memory from damaging these regions.
Note that this feature *does not* check calls to the esp_rom_xxx SPI flash ROM functions. These functions should not be called directly from IDF applications.
- Available options:
Aborts (SPI_FLASH_DANGEROUS_WRITE_ABORTS)
Fails (SPI_FLASH_DANGEROUS_WRITE_FAILS)
Allowed (SPI_FLASH_DANGEROUS_WRITE_ALLOWED)
CONFIG_SPI_FLASH_USE_LEGACY_IMPL¶
Use the legacy implementation before IDF v4.0
Found in: Component config > SPI Flash driver
The implementation of SPI flash has been greatly changed in IDF v4.0. Enable this option to use the legacy implementation.
CONFIG_SPI_FLASH_BYPASS_BLOCK_ERASE¶
Bypass a block erase and always do sector erase
Found in: Component config > SPI Flash driver
Some flash chips can have very high “max” erase times, especially for block erase (32KB or 64KB). This option allows to bypass “block erase” and always do sector erase commands. This will be much slower overall in most cases, but improves latency for other code to run.
CONFIG_SPI_FLASH_YIELD_DURING_ERASE¶
Enables yield operation during flash erase
Found in: Component config > SPI Flash driver
This allows to yield the CPUs between erase commands. Prevents starvation of other tasks.
CONFIG_SPI_FLASH_ERASE_YIELD_DURATION_MS¶
Duration of erasing to yield CPUs (ms)
Found in: Component config > SPI Flash driver > CONFIG_SPI_FLASH_YIELD_DURING_ERASE
If a duration of one erase command is large then it will yield CPUs after finishing a current command.
CONFIG_SPI_FLASH_ERASE_YIELD_TICKS¶
CPU release time (tick)
Found in: Component config > SPI Flash driver > CONFIG_SPI_FLASH_YIELD_DURING_ERASE
Defines how many ticks will be before returning to continue a erasing.
CONFIG_SPI_FLASH_SIZE_OVERRIDE¶
Override flash size in bootloader header by ESPTOOLPY_FLASHSIZE
Found in: Component config > SPI Flash driver
SPI Flash driver uses the flash size configured in bootloader header by default. Enable this option to override flash size with latest ESPTOOLPY_FLASHSIZE value from the app header if the size in the bootloader header is incorrect.
Auto-detect flash chips¶
Contains:
CONFIG_SPI_FLASH_SUPPORT_ISSI_CHIP¶
ISSI
Found in: Component config > SPI Flash driver > Auto-detect flash chips
Enable this to support auto detection of ISSI chips if chip vendor not directly given by
chip\_drvmember of the chip struct. This adds support for variant chips, however will extend detecting time.
CONFIG_SPI_FLASH_SUPPORT_MXIC_CHIP¶
MXIC
Found in: Component config > SPI Flash driver > Auto-detect flash chips
Enable this to support auto detection of MXIC chips if chip vendor not directly given by
chip\_drvmember of the chip struct. This adds support for variant chips, however will extend detecting time.
CONFIG_SPI_FLASH_SUPPORT_GD_CHIP¶
GigaDevice
Found in: Component config > SPI Flash driver > Auto-detect flash chips
Enable this to support auto detection of GD (GigaDevice) chips if chip vendor not directly given by
chip\_drvmember of the chip struct. If you are using Wrover modules, please don’t disable this, otherwise your flash may not work in 4-bit mode.This adds support for variant chips, however will extend detecting time and image size. Note that the default chip driver supports the GD chips with product ID 60H.
CONFIG_SPI_FLASH_ENABLE_ENCRYPTED_READ_WRITE¶
Enable encrypted partition read/write operations
Found in: Component config > SPI Flash driver
This option enables flash read/write operations to encrypted partition/s. This option is kept enabled irrespective of state of flash encryption feature. However, in case application is not using flash encryption feature and is in need of some additional memory from IRAM region (~1KB) then this config can be disabled.
ADC-Calibration¶
Log output¶
Contains:
CONFIG_LOG_DEFAULT_LEVEL¶
Default log verbosity
Found in: Component config > Log output
Specify how much output to see in logs by default. You can set lower verbosity level at runtime using esp_log_level_set function.
Note that this setting limits which log statements are compiled into the program. So setting this to, say, “Warning” would mean that changing log level to “Debug” at runtime will not be possible.
- Available options:
No output (LOG_DEFAULT_LEVEL_NONE)
Error (LOG_DEFAULT_LEVEL_ERROR)
Warning (LOG_DEFAULT_LEVEL_WARN)
Info (LOG_DEFAULT_LEVEL_INFO)
Debug (LOG_DEFAULT_LEVEL_DEBUG)
Verbose (LOG_DEFAULT_LEVEL_VERBOSE)
CONFIG_LOG_COLORS¶
Use ANSI terminal colors in log output
Found in: Component config > Log output
Enable ANSI terminal color codes in bootloader output.
In order to view these, your terminal program must support ANSI color codes.
CONFIG_LOG_TIMESTAMP_SOURCE¶
Log Timestamps
Found in: Component config > Log output
Choose what sort of timestamp is displayed in the log output:
Milliseconds since boot is calulated from the RTOS tick count multiplied by the tick period. This time will reset after a software reboot. e.g. (90000)
System time is taken from POSIX time functions which use the ESP32’s RTC and FRC1 timers to maintain an accurate time. The system time is initialized to 0 on startup, it can be set with an SNTP sync, or with POSIX time functions. This time will not reset after a software reboot. e.g. (00:01:30.000)
NOTE: Currently this will not get used in logging from binary blobs (i.e WiFi & Bluetooth libraries), these will always print milliseconds since boot.
- Available options:
Milliseconds Since Boot (LOG_TIMESTAMP_SOURCE_RTOS)
System Time (LOG_TIMESTAMP_SOURCE_SYSTEM)
Unity unit testing library¶
Contains:
CONFIG_UNITY_ENABLE_FLOAT¶
Support for float type
Found in: Component config > Unity unit testing library
If not set, assertions on float arguments will not be available.
CONFIG_UNITY_ENABLE_DOUBLE¶
Support for double type
Found in: Component config > Unity unit testing library
If not set, assertions on double arguments will not be available.
CONFIG_UNITY_ENABLE_COLOR¶
Colorize test output
Found in: Component config > Unity unit testing library
If set, Unity will colorize test results using console escape sequences.
CONFIG_UNITY_ENABLE_IDF_TEST_RUNNER¶
Include ESP-IDF test registration/running helpers
Found in: Component config > Unity unit testing library
If set, then the following features will be available:
TEST_CASE macro which performs automatic registration of test functions
Functions to run registered test functions: unity_run_all_tests, unity_run_tests_with_filter, unity_run_single_test_by_name.
Interactive menu which lists test cases and allows choosing the tests to be run, available via unity_run_menu function.
Disable if a different test registration mechanism is used.
CONFIG_UNITY_ENABLE_FIXTURE¶
Include Unity test fixture
Found in: Component config > Unity unit testing library
If set, unity_fixture.h header file and associated source files are part of the build. These provide an optional set of macros and functions to implement test groups.
CONFIG_UNITY_ENABLE_BACKTRACE_ON_FAIL¶
Print a backtrace when a unit test fails
Found in: Component config > Unity unit testing library
If set, the unity framework will print the backtrace information before jumping back to the test menu. The jumping is usually occurs in assert functions such as TEST_ASSERT, TEST_FAIL etc.
Modbus configuration¶
Contains:
CONFIG_FMB_COMM_MODE_RTU_EN¶
Enable Modbus stack support for RTU mode
Found in: Component config > Modbus configuration
Enable RTU Modbus communication mode option for Modbus serial stack.
CONFIG_FMB_COMM_MODE_ASCII_EN¶
Enable Modbus stack support for ASCII mode
Found in: Component config > Modbus configuration
Enable ASCII Modbus communication mode option for Modbus serial stack.
CONFIG_FMB_MASTER_TIMEOUT_MS_RESPOND¶
Slave respond timeout (Milliseconds)
Found in: Component config > Modbus configuration
If master sends a frame which is not broadcast, it has to wait sometime for slave response. if slave is not respond in this time, the master will process timeout error.
CONFIG_FMB_MASTER_DELAY_MS_CONVERT¶
Slave conversion delay (Milliseconds)
Found in: Component config > Modbus configuration
If master sends a broadcast frame, it has to wait conversion time to delay, then master can send next frame.
CONFIG_FMB_QUEUE_LENGTH¶
Modbus serial task queue length
Found in: Component config > Modbus configuration
Modbus serial driver queue length. It is used by event queue task. See the serial driver API for more information.
CONFIG_FMB_SERIAL_TASK_STACK_SIZE¶
Modbus serial task stack size
Found in: Component config > Modbus configuration
Modbus serial task stack size for event queue task. It may be adjusted when debugging is enabled (for example).
CONFIG_FMB_SERIAL_BUF_SIZE¶
Modbus serial task RX/TX buffer size
Found in: Component config > Modbus configuration
Modbus serial task RX and TX buffer size for UART driver initialization. This buffer is used for modbus frame transfer. The Modbus protocol maximum frame size is 256 bytes. Bigger size can be used for non standard implementations.
CONFIG_FMB_SERIAL_ASCII_BITS_PER_SYMB¶
Number of data bits per ASCII character
Found in: Component config > Modbus configuration
This option defines the number of data bits per ASCII character.
CONFIG_FMB_SERIAL_ASCII_TIMEOUT_RESPOND_MS¶
Response timeout for ASCII communication mode (ms)
Found in: Component config > Modbus configuration
This option defines response timeout of slave in milliseconds for ASCII communication mode. Thus the timeout will expire and allow the master program to handle the error.
CONFIG_FMB_SERIAL_TASK_PRIO¶
Modbus serial task priority
Found in: Component config > Modbus configuration
Modbus UART driver event task priority. The priority of Modbus controller task is equal to (CONFIG_FMB_SERIAL_TASK_PRIO - 1).
CONFIG_FMB_PORT_TASK_AFFINITY¶
Modbus task affinity
Found in: Component config > Modbus configuration
Allows setting the core affinity of the Modbus controller task, i.e. whether the task is pinned to particular CPU, or allowed to run on any CPU.
- Available options:
No affinity (FMB_PORT_TASK_AFFINITY_NO_AFFINITY)
CPU0 (FMB_PORT_TASK_AFFINITY_CPU0)
CPU1 (FMB_PORT_TASK_AFFINITY_CPU1)
CONFIG_FMB_CONTROLLER_SLAVE_ID_SUPPORT¶
Modbus controller slave ID support
Found in: Component config > Modbus configuration
Modbus slave ID support enable. When enabled the Modbus <Report Slave ID> command is supported by stack.
CONFIG_FMB_CONTROLLER_SLAVE_ID¶
Modbus controller slave ID
Found in: Component config > Modbus configuration > CONFIG_FMB_CONTROLLER_SLAVE_ID_SUPPORT
Modbus slave ID value to identify modbus device in the network using <Report Slave ID> command. Most significant byte of ID is used as short device ID and other three bytes used as long ID.
CONFIG_FMB_CONTROLLER_NOTIFY_TIMEOUT¶
Modbus controller notification timeout (ms)
Found in: Component config > Modbus configuration
Modbus controller notification timeout in milliseconds. This timeout is used to send notification about accessed parameters.
CONFIG_FMB_CONTROLLER_NOTIFY_QUEUE_SIZE¶
Modbus controller notification queue size
Found in: Component config > Modbus configuration
Modbus controller notification queue size. The notification queue is used to get information about accessed parameters.
CONFIG_FMB_CONTROLLER_STACK_SIZE¶
Modbus controller stack size
Found in: Component config > Modbus configuration
Modbus controller task stack size. The Stack size may be adjusted when debug mode is used which requires more stack size (for example).
CONFIG_FMB_EVENT_QUEUE_TIMEOUT¶
Modbus stack event queue timeout (ms)
Found in: Component config > Modbus configuration
Modbus stack event queue timeout in milliseconds. This may help to optimize Modbus stack event processing time.
CONFIG_FMB_TIMER_PORT_ENABLED¶
Modbus stack use timer for 3.5T symbol time measurement
Found in: Component config > Modbus configuration
If this option is set the Modbus stack uses timer for T3.5 time measurement. Else the internal UART TOUT timeout is used for 3.5T symbol time measurement.
CONFIG_FMB_TIMER_GROUP¶
Slave Timer group number
Found in: Component config > Modbus configuration
Modbus slave Timer group number that is used for timeout measurement.
CONFIG_FMB_TIMER_INDEX¶
Slave Timer index in the group
Found in: Component config > Modbus configuration
Modbus slave Timer Index in the group that is used for timeout measurement.
CONFIG_FMB_MASTER_TIMER_GROUP¶
Master Timer group number
Found in: Component config > Modbus configuration
Modbus master Timer group number that is used for timeout measurement.
CONFIG_FMB_MASTER_TIMER_INDEX¶
Master Timer index
Found in: Component config > Modbus configuration
Modbus master Timer Index in the group that is used for timeout measurement. Note: Modbus master and slave should have different timer index to be able to work simultaneously.
CONFIG_FMB_TIMER_ISR_IN_IRAM¶
Place timer interrupt handler into IRAM
Found in: Component config > Modbus configuration
This option places Modbus timer IRQ handler into IRAM. This allows to avoid delays related to processing of non-IRAM-safe interrupts during a flash write operation (NVS updating a value, or some other flash API which has to perform an read/write operation and disable CPU cache). This option has dependency with the UART_ISR_IN_IRAM option which places UART interrupt handler into IRAM to prevent delays related to processing of UART events.
Event Loop Library¶
Contains:
CONFIG_ESP_EVENT_LOOP_PROFILING¶
Enable event loop profiling
Found in: Component config > Event Loop Library
Enables collections of statistics in the event loop library such as the number of events posted to/recieved by an event loop, number of callbacks involved, number of events dropped to to a full event loop queue, run time of event handlers, and number of times/run time of each event handler.
CONFIG_ESP_EVENT_POST_FROM_ISR¶
Support posting events from ISRs
Found in: Component config > Event Loop Library
Enable posting events from interrupt handlers.
CONFIG_ESP_EVENT_POST_FROM_IRAM_ISR¶
Support posting events from ISRs placed in IRAM
Found in: Component config > Event Loop Library > CONFIG_ESP_EVENT_POST_FROM_ISR
Enable posting events from interrupt handlers placed in IRAM. Enabling this option places API functions esp_event_post and esp_event_post_to in IRAM.
ESP System Settings¶
Contains:
CONFIG_ESP_SYSTEM_PANIC¶
Panic handler behaviour
Found in: Component config > ESP System Settings
If FreeRTOS detects unexpected behaviour or an unhandled exception, the panic handler is invoked. Configure the panic handler’s action here.
- Available options:
Print registers and halt (ESP_SYSTEM_PANIC_PRINT_HALT)
Outputs the relevant registers over the serial port and halt the processor. Needs a manual reset to restart.
Print registers and reboot (ESP_SYSTEM_PANIC_PRINT_REBOOT)
Outputs the relevant registers over the serial port and immediately reset the processor.
Silent reboot (ESP_SYSTEM_PANIC_SILENT_REBOOT)
Just resets the processor without outputting anything
Invoke GDBStub (ESP_SYSTEM_PANIC_GDBSTUB)
Invoke gdbstub on the serial port, allowing for gdb to attach to it to do a postmortem of the crash.
Application Level Tracing¶
Contains:
CONFIG_APPTRACE_DESTINATION¶
Data Destination
Found in: Component config > Application Level Tracing
Select destination for application trace: trace memory or none (to disable).
- Available options:
Trace memory (APPTRACE_DEST_TRAX)
None (APPTRACE_DEST_NONE)
CONFIG_APPTRACE_ONPANIC_HOST_FLUSH_TMO¶
Timeout for flushing last trace data to host on panic
Found in: Component config > Application Level Tracing
Timeout for flushing last trace data to host in case of panic. In ms. Use -1 to disable timeout and wait forever.
CONFIG_APPTRACE_POSTMORTEM_FLUSH_THRESH¶
Threshold for flushing last trace data to host on panic
Found in: Component config > Application Level Tracing
Threshold for flushing last trace data to host on panic in post-mortem mode. This is minimal amount of data needed to perform flush. In bytes.
CONFIG_APPTRACE_PENDING_DATA_SIZE_MAX¶
Size of the pending data buffer
Found in: Component config > Application Level Tracing
Size of the buffer for events in bytes. It is useful for buffering events from the time critical code (scheduler, ISRs etc). If this parameter is 0 then events will be discarded when main HW buffer is full.
FreeRTOS SystemView Tracing¶
Contains:
CONFIG_SYSVIEW_ENABLE¶
SystemView Tracing Enable
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing
Enables supporrt for SEGGER SystemView tracing functionality.
CONFIG_SYSVIEW_TS_SOURCE¶
Timer to use as timestamp source
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing > CONFIG_SYSVIEW_ENABLE
SystemView needs to use a hardware timer as the source of timestamps when tracing. This option selects the timer for it.
- Available options:
CPU cycle counter (CCOUNT) (SYSVIEW_TS_SOURCE_CCOUNT)
Timer 0, Group 0 (SYSVIEW_TS_SOURCE_TIMER_00)
Timer 1, Group 0 (SYSVIEW_TS_SOURCE_TIMER_01)
Timer 0, Group 1 (SYSVIEW_TS_SOURCE_TIMER_10)
Timer 1, Group 1 (SYSVIEW_TS_SOURCE_TIMER_11)
esp_timer high resolution timer (SYSVIEW_TS_SOURCE_ESP_TIMER)
CONFIG_SYSVIEW_MAX_TASKS¶
Maximum supported tasks
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing > CONFIG_SYSVIEW_ENABLE
Configures maximum supported tasks in sysview debug
CONFIG_SYSVIEW_BUF_WAIT_TMO¶
Trace buffer wait timeout
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing > CONFIG_SYSVIEW_ENABLE
Configures timeout (in us) to wait for free space in trace buffer. Set to -1 to wait forever and avoid lost events.
CONFIG_SYSVIEW_EVT_OVERFLOW_ENABLE¶
Trace Buffer Overflow Event
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing > CONFIG_SYSVIEW_ENABLE
Enables “Trace Buffer Overflow” event.
CONFIG_SYSVIEW_EVT_ISR_ENTER_ENABLE¶
ISR Enter Event
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing > CONFIG_SYSVIEW_ENABLE
Enables “ISR Enter” event.
CONFIG_SYSVIEW_EVT_ISR_EXIT_ENABLE¶
ISR Exit Event
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing > CONFIG_SYSVIEW_ENABLE
Enables “ISR Exit” event.
CONFIG_SYSVIEW_EVT_ISR_TO_SCHEDULER_ENABLE¶
ISR Exit to Scheduler Event
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing > CONFIG_SYSVIEW_ENABLE
Enables “ISR to Scheduler” event.
CONFIG_SYSVIEW_EVT_TASK_START_EXEC_ENABLE¶
Task Start Execution Event
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing > CONFIG_SYSVIEW_ENABLE
Enables “Task Start Execution” event.
CONFIG_SYSVIEW_EVT_TASK_STOP_EXEC_ENABLE¶
Task Stop Execution Event
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing > CONFIG_SYSVIEW_ENABLE
Enables “Task Stop Execution” event.
CONFIG_SYSVIEW_EVT_TASK_START_READY_ENABLE¶
Task Start Ready State Event
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing > CONFIG_SYSVIEW_ENABLE
Enables “Task Start Ready State” event.
CONFIG_SYSVIEW_EVT_TASK_STOP_READY_ENABLE¶
Task Stop Ready State Event
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing > CONFIG_SYSVIEW_ENABLE
Enables “Task Stop Ready State” event.
CONFIG_SYSVIEW_EVT_TASK_CREATE_ENABLE¶
Task Create Event
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing > CONFIG_SYSVIEW_ENABLE
Enables “Task Create” event.
CONFIG_SYSVIEW_EVT_TASK_TERMINATE_ENABLE¶
Task Terminate Event
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing > CONFIG_SYSVIEW_ENABLE
Enables “Task Terminate” event.
CONFIG_SYSVIEW_EVT_IDLE_ENABLE¶
System Idle Event
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing > CONFIG_SYSVIEW_ENABLE
Enables “System Idle” event.
CONFIG_SYSVIEW_EVT_TIMER_ENTER_ENABLE¶
Timer Enter Event
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing > CONFIG_SYSVIEW_ENABLE
Enables “Timer Enter” event.
CONFIG_SYSVIEW_EVT_TIMER_EXIT_ENABLE¶
Timer Exit Event
Found in: Component config > Application Level Tracing > FreeRTOS SystemView Tracing > CONFIG_SYSVIEW_ENABLE
Enables “Timer Exit” event.
CONFIG_APPTRACE_GCOV_ENABLE¶
GCOV to Host Enable
Found in: Component config > Application Level Tracing
Enables support for GCOV data transfer to host.
PThreads¶
Contains:
CONFIG_PTHREAD_TASK_PRIO_DEFAULT¶
Default task priority
Found in: Component config > PThreads
Priority used to create new tasks with default pthread parameters.
CONFIG_PTHREAD_TASK_STACK_SIZE_DEFAULT¶
Default task stack size
Found in: Component config > PThreads
Stack size used to create new tasks with default pthread parameters.
CONFIG_PTHREAD_STACK_MIN¶
Minimum allowed pthread stack size
Found in: Component config > PThreads
Minimum allowed pthread stack size set in attributes passed to pthread_create
CONFIG_PTHREAD_TASK_CORE_DEFAULT¶
Default pthread core affinity
Found in: Component config > PThreads
The default core to which pthreads are pinned.
- Available options:
No affinity (PTHREAD_DEFAULT_CORE_NO_AFFINITY)
Core 0 (PTHREAD_DEFAULT_CORE_0)
Core 1 (PTHREAD_DEFAULT_CORE_1)
CONFIG_PTHREAD_TASK_NAME_DEFAULT¶
Heap memory debugging¶
Contains:
CONFIG_HEAP_CORRUPTION_DETECTION¶
Heap corruption detection
Found in: Component config > Heap memory debugging
Enable heap poisoning features to detect heap corruption caused by out-of-bounds access to heap memory.
See the “Heap Memory Debugging” page of the IDF documentation for a description of each level of heap corruption detection.
- Available options:
Basic (no poisoning) (HEAP_POISONING_DISABLED)
Light impact (HEAP_POISONING_LIGHT)
Comprehensive (HEAP_POISONING_COMPREHENSIVE)
CONFIG_HEAP_TRACING_DEST¶
Heap tracing
Found in: Component config > Heap memory debugging
Enables the heap tracing API defined in esp_heap_trace.h.
This function causes a moderate increase in IRAM code side and a minor increase in heap function (malloc/free/realloc) CPU overhead, even when the tracing feature is not used. So it’s best to keep it disabled unless tracing is being used.
- Available options:
Disabled (HEAP_TRACING_OFF)
Standalone (HEAP_TRACING_STANDALONE)
Host-based (HEAP_TRACING_TOHOST)
CONFIG_HEAP_TRACING_STACK_DEPTH¶
Heap tracing stack depth
Found in: Component config > Heap memory debugging
Number of stack frames to save when tracing heap operation callers.
More stack frames uses more memory in the heap trace buffer (and slows down allocation), but can provide useful information.
CONFIG_HEAP_TASK_TRACKING¶
Enable heap task tracking
Found in: Component config > Heap memory debugging
Enables tracking the task responsible for each heap allocation.
This function depends on heap poisoning being enabled and adds four more bytes of overhead for each block allocated.
CONFIG_HEAP_ABORT_WHEN_ALLOCATION_FAILS¶
Abort if memory allocation fails
Found in: Component config > Heap memory debugging
When enabled, if a memory allocation operation fails it will cause a system abort.
Wear Levelling¶
Contains:
CONFIG_WL_SECTOR_SIZE¶
Wear Levelling library sector size
Found in: Component config > Wear Levelling
Sector size used by wear levelling library. You can set default sector size or size that will fit to the flash device sector size.
With sector size set to 4096 bytes, wear levelling library is more efficient. However if FAT filesystem is used on top of wear levelling library, it will need more temporary storage: 4096 bytes for each mounted filesystem and 4096 bytes for each opened file.
With sector size set to 512 bytes, wear levelling library will perform more operations with flash memory, but less RAM will be used by FAT filesystem library (512 bytes for the filesystem and 512 bytes for each file opened).
- Available options:
512 (WL_SECTOR_SIZE_512)
4096 (WL_SECTOR_SIZE_4096)
CONFIG_WL_SECTOR_MODE¶
Sector store mode
Found in: Component config > Wear Levelling
Specify the mode to store data into flash:
In Performance mode a data will be stored to the RAM and then stored back to the flash. Compared to the Safety mode, this operation is faster, but if power will be lost when erase sector operation is in progress, then the data from complete flash device sector will be lost.
In Safety mode data from complete flash device sector will be read from flash, modified, and then stored back to flash. Compared to the Performance mode, this operation is slower, but if power is lost during erase sector operation, then the data from full flash device sector will not be lost.
- Available options:
Perfomance (WL_SECTOR_MODE_PERF)
Safety (WL_SECTOR_MODE_SAFE)
Supplicant¶
Contains:
CONFIG_WPA_MBEDTLS_CRYPTO¶
Use MbedTLS crypto API’s
Found in: Component config > Supplicant
Select this option to use MbedTLS crypto API’s which utilize hardware acceleration.
CONFIG_WPA_DEBUG_PRINT¶
Print debug messages from WPA Supplicant
Found in: Component config > Supplicant
Select this option to print logging information from WPA supplicant, this includes handshake information and key hex dumps depending on the project logging level.
Enabling this could increase the build size ~60kb depending on the project logging level.
CONFIG_WPA_TESTING_OPTIONS¶
Add DPP testing code
Found in: Component config > Supplicant
Select this to enable unity test for DPP.
CONFIG_WPA_WPS_STRICT¶
Strictly validate all WPS attributes
Found in: Component config > Supplicant
Select this option to enable validate each WPS attribute rigorously. Disabling this add the workaorunds with various APs. Enabling this may cause inter operability issues with some APs.
CoAP Configuration¶
Contains:
CONFIG_COAP_MBEDTLS_ENCRYPTION_MODE¶
CoAP Encryption method
Found in: Component config > CoAP Configuration
If the CoAP information is to be encrypted, the encryption environment can be set up in one of two ways (default being Pre-Shared key mode)
Encrypt using defined Pre-Shared Keys (PSK if uri includes coaps://)
Encrypt using defined Public Key Infrastructure (PKI if uri includes coaps://)
- Available options:
Pre-Shared Keys (COAP_MBEDTLS_PSK)
PKI Certificates (COAP_MBEDTLS_PKI)
CONFIG_COAP_MBEDTLS_DEBUG¶
Enable CoAP debugging
Found in: Component config > CoAP Configuration
Enable CoAP debugging functions at compile time for the example code.
If this option is enabled, call coap_set_log_level() at runtime in order to enable CoAP debug output via the ESP log mechanism.
CONFIG_COAP_MBEDTLS_DEBUG_LEVEL¶
Set CoAP debugging level
Found in: Component config > CoAP Configuration > CONFIG_COAP_MBEDTLS_DEBUG
Set CoAP debugging level
- Available options:
Emergency (COAP_LOG_EMERG)
Alert (COAP_LOG_ALERT)
Critical (COAP_LOG_CRIT)
Error (COAP_LOG_ERROR)
Warning (COAP_LOG_WARNING)
Notice (COAP_LOG_NOTICE)
Info (COAP_LOG_INFO)
Debug (COAP_LOG_DEBUG)
Newlib¶
Contains:
CONFIG_NEWLIB_STDOUT_LINE_ENDING¶
Line ending for UART output
Found in: Component config > Newlib
This option allows configuring the desired line endings sent to UART when a newline (‘n’, LF) appears on stdout. Three options are possible:
CRLF: whenever LF is encountered, prepend it with CR
LF: no modification is applied, stdout is sent as is
CR: each occurence of LF is replaced with CR
This option doesn’t affect behavior of the UART driver (drivers/uart.h).
- Available options:
CRLF (NEWLIB_STDOUT_LINE_ENDING_CRLF)
LF (NEWLIB_STDOUT_LINE_ENDING_LF)
CR (NEWLIB_STDOUT_LINE_ENDING_CR)
CONFIG_NEWLIB_STDIN_LINE_ENDING¶
Line ending for UART input
Found in: Component config > Newlib
This option allows configuring which input sequence on UART produces a newline (‘n’, LF) on stdin. Three options are possible:
CRLF: CRLF is converted to LF
LF: no modification is applied, input is sent to stdin as is
CR: each occurence of CR is replaced with LF
This option doesn’t affect behavior of the UART driver (drivers/uart.h).
- Available options:
CRLF (NEWLIB_STDIN_LINE_ENDING_CRLF)
LF (NEWLIB_STDIN_LINE_ENDING_LF)
CR (NEWLIB_STDIN_LINE_ENDING_CR)
CONFIG_NEWLIB_NANO_FORMAT¶
Enable ‘nano’ formatting options for printf/scanf family
Found in: Component config > Newlib
ESP32 ROM contains parts of newlib C library, including printf/scanf family of functions. These functions have been compiled with so-called “nano” formatting option. This option doesn’t support 64-bit integer formats and C99 features, such as positional arguments.
For more details about “nano” formatting option, please see newlib readme file, search for ‘–enable-newlib-nano-formatted-io’: https://sourceware.org/newlib/README
If this option is enabled, build system will use functions available in ROM, reducing the application binary size. Functions available in ROM run faster than functions which run from flash. Functions available in ROM can also run when flash instruction cache is disabled.
If you need 64-bit integer formatting support or C99 features, keep this option disabled.
SPIFFS Configuration¶
Contains:
CONFIG_SPIFFS_MAX_PARTITIONS¶
Maximum Number of Partitions
Found in: Component config > SPIFFS Configuration
Define maximum number of partitions that can be mounted.
SPIFFS Cache Configuration¶
Contains:
CONFIG_SPIFFS_CACHE¶
Enable SPIFFS Cache
Found in: Component config > SPIFFS Configuration > SPIFFS Cache Configuration
Enables/disable memory read caching of nucleus file system operations.
CONFIG_SPIFFS_CACHE_WR¶
Enable SPIFFS Write Caching
Found in: Component config > SPIFFS Configuration > SPIFFS Cache Configuration > CONFIG_SPIFFS_CACHE
Enables memory write caching for file descriptors in hydrogen.
CONFIG_SPIFFS_CACHE_STATS¶
Enable SPIFFS Cache Statistics
Found in: Component config > SPIFFS Configuration > SPIFFS Cache Configuration > CONFIG_SPIFFS_CACHE
Enable/disable statistics on caching. Debug/test purpose only.
CONFIG_SPIFFS_PAGE_CHECK¶
Enable SPIFFS Page Check
Found in: Component config > SPIFFS Configuration
Always check header of each accessed page to ensure consistent state. If enabled it will increase number of reads from flash, especially if cache is disabled.
CONFIG_SPIFFS_GC_MAX_RUNS¶
Set Maximum GC Runs
Found in: Component config > SPIFFS Configuration
Define maximum number of GC runs to perform to reach desired free pages.
CONFIG_SPIFFS_GC_STATS¶
Enable SPIFFS GC Statistics
Found in: Component config > SPIFFS Configuration
Enable/disable statistics on gc. Debug/test purpose only.
CONFIG_SPIFFS_PAGE_SIZE¶
SPIFFS logical page size
Found in: Component config > SPIFFS Configuration
Logical page size of SPIFFS partition, in bytes. Must be multiple of flash page size (which is usually 256 bytes). Larger page sizes reduce overhead when storing large files, and improve filesystem performance when reading large files. Smaller page sizes reduce overhead when storing small (< page size) files.
CONFIG_SPIFFS_OBJ_NAME_LEN¶
Set SPIFFS Maximum Name Length
Found in: Component config > SPIFFS Configuration
Object name maximum length. Note that this length include the zero-termination character, meaning maximum string of characters can at most be SPIFFS_OBJ_NAME_LEN - 1.
SPIFFS_OBJ_NAME_LEN + SPIFFS_META_LENGTH should not exceed SPIFFS_PAGE_SIZE - 64.
CONFIG_SPIFFS_FOLLOW_SYMLINKS¶
Enable symbolic links for image creation
Found in: Component config > SPIFFS Configuration
If this option is enabled, symbolic links are taken into account during partition image creation.
CONFIG_SPIFFS_USE_MAGIC¶
Enable SPIFFS Filesystem Magic
Found in: Component config > SPIFFS Configuration
Enable this to have an identifiable spiffs filesystem. This will look for a magic in all sectors to determine if this is a valid spiffs system or not at mount time.
CONFIG_SPIFFS_USE_MAGIC_LENGTH¶
Enable SPIFFS Filesystem Length Magic
Found in: Component config > SPIFFS Configuration > CONFIG_SPIFFS_USE_MAGIC
If this option is enabled, the magic will also be dependent on the length of the filesystem. For example, a filesystem configured and formatted for 4 megabytes will not be accepted for mounting with a configuration defining the filesystem as 2 megabytes.
CONFIG_SPIFFS_META_LENGTH¶
Size of per-file metadata field
Found in: Component config > SPIFFS Configuration
This option sets the number of extra bytes stored in the file header. These bytes can be used in an application-specific manner. Set this to at least 4 bytes to enable support for saving file modification time.
SPIFFS_OBJ_NAME_LEN + SPIFFS_META_LENGTH should not exceed SPIFFS_PAGE_SIZE - 64.
CONFIG_SPIFFS_USE_MTIME¶
Save file modification time
Found in: Component config > SPIFFS Configuration
If enabled, then the first 4 bytes of per-file metadata will be used to store file modification time (mtime), accessible through stat/fstat functions. Modification time is updated when the file is opened.
CONFIG_SPIFFS_MTIME_WIDE_64_BITS¶
The time field occupies 64 bits in the image instead of 32 bits
Found in: Component config > SPIFFS Configuration
If this option is not set, the time field is 32 bits (up to 2106 year), otherwise it is 64 bits and make sure it matches SPIFFS_META_LENGTH. If the chip already has the spiffs image with the time field = 32 bits then this option cannot be applied in this case. Erase it first before using this option. To resolve the Y2K38 problem for the spiffs, use a toolchain with support time_t 64 bits (see SDK_TOOLCHAIN_SUPPORTS_TIME_WIDE_64_BITS).
Debug Configuration¶
Contains:
CONFIG_SPIFFS_DBG¶
Enable general SPIFFS debug
Found in: Component config > SPIFFS Configuration > Debug Configuration
Enabling this option will print general debug mesages to the console.
CONFIG_SPIFFS_API_DBG¶
Enable SPIFFS API debug
Found in: Component config > SPIFFS Configuration > Debug Configuration
Enabling this option will print API debug mesages to the console.
CONFIG_SPIFFS_GC_DBG¶
Enable SPIFFS Garbage Cleaner debug
Found in: Component config > SPIFFS Configuration > Debug Configuration
Enabling this option will print GC debug mesages to the console.
CONFIG_SPIFFS_CACHE_DBG¶
Enable SPIFFS Cache debug
Found in: Component config > SPIFFS Configuration > Debug Configuration
Enabling this option will print cache debug mesages to the console.
CONFIG_SPIFFS_CHECK_DBG¶
Enable SPIFFS Filesystem Check debug
Found in: Component config > SPIFFS Configuration > Debug Configuration
Enabling this option will print Filesystem Check debug mesages to the console.
CONFIG_SPIFFS_TEST_VISUALISATION¶
Enable SPIFFS Filesystem Visualization
Found in: Component config > SPIFFS Configuration > Debug Configuration
Enable this option to enable SPIFFS_vis function in the API.
Virtual file system¶
Contains:
CONFIG_VFS_SUPPORT_IO¶
Provide basic I/O functions
Found in: Component config > Virtual file system
If enabled, the following functions are provided by the VFS component.
open, close, read, write, pread, pwrite, lseek, fstat, fsync, ioctl, fcntl
Filesystem drivers can then be registered to handle these functions for specific paths.
Disabling this option can save memory when the support for these functions is not required.
CONFIG_VFS_SUPPORT_DIR¶
Provide directory related functions
Found in: Component config > Virtual file system > CONFIG_VFS_SUPPORT_IO
If enabled, the following functions are provided by the VFS component.
stat, link, unlink, rename, utime, access, truncate, rmdir, mkdir, opendir, closedir, readdir, readdir_r, seekdir, telldir, rewinddir
Filesystem drivers can then be registered to handle these functions for specific paths.
Disabling this option can save memory when the support for these functions is not required.
CONFIG_VFS_SUPPORT_SELECT¶
Provide select function
Found in: Component config > Virtual file system > CONFIG_VFS_SUPPORT_IO
If enabled, select function is provided by the VFS component, and can be used on peripheral file descriptors (such as UART) and sockets at the same time.
If disabled, the default select implementation will be provided by LWIP for sockets only.
Disabling this option can reduce code size if support for “select” on UART file descriptors is not required.
CONFIG_VFS_SUPPRESS_SELECT_DEBUG_OUTPUT¶
Suppress select() related debug outputs
Found in: Component config > Virtual file system > CONFIG_VFS_SUPPORT_IO > CONFIG_VFS_SUPPORT_SELECT
Select() related functions might produce an unconveniently lot of debug outputs when one sets the default log level to DEBUG or higher. It is possible to suppress these debug outputs by enabling this option.
CONFIG_VFS_SUPPORT_TERMIOS¶
Provide termios.h functions
Found in: Component config > Virtual file system > CONFIG_VFS_SUPPORT_IO
Disabling this option can save memory when the support for termios.h is not required.
Host File System I/O (Semihosting)¶
Contains:
CONFIG_VFS_SEMIHOSTFS_MAX_MOUNT_POINTS¶
Host FS: Maximum number of the host filesystem mount points
Found in: Component config > Virtual file system > CONFIG_VFS_SUPPORT_IO > Host File System I/O (Semihosting)
Define maximum number of host filesystem mount points.
CONFIG_VFS_SEMIHOSTFS_HOST_PATH_MAX_LEN¶
Host FS: Maximum path length for the host base directory
Found in: Component config > Virtual file system > CONFIG_VFS_SUPPORT_IO > Host File System I/O (Semihosting)
Define maximum path length for the host base directory which is to be mounted. If host path passed to esp_vfs_semihost_register() is longer than this value it will be truncated.
NVS¶
Contains:
CONFIG_NVS_ENCRYPTION¶
Enable NVS encryption
Found in: Component config > NVS
This option enables encryption for NVS. When enabled, AES-XTS is used to encrypt the complete NVS data, except the page headers. It requires XTS encryption keys to be stored in an encrypted partition. This means enabling flash encryption is a pre-requisite for this feature.
FreeRTOS¶
Contains:
CONFIG_FREERTOS_UNICORE¶
Run FreeRTOS only on first core
Found in: Component config > FreeRTOS
This version of FreeRTOS normally takes control of all cores of the CPU. Select this if you only want to start it on the first core. This is needed when e.g. another process needs complete control over the second core.
# This invisible config value sets the value of tskNO_AFFINITY in task.h. # Intended to be used as a constant from other Kconfig files. # Value is (32-bit) INT_MAX.
CONFIG_FREERTOS_CORETIMER¶
Xtensa timer to use as the FreeRTOS tick source
Found in: Component config > FreeRTOS
FreeRTOS needs a timer with an associated interrupt to use as the main tick source to increase counters, run timers and do pre-emptive multitasking with. There are multiple timers available to do this, with different interrupt priorities. Check
- Available options:
Timer 0 (int 6, level 1) (FREERTOS_CORETIMER_0)
Select this to use timer 0
Timer 1 (int 15, level 3) (FREERTOS_CORETIMER_1)
Select this to use timer 1
CONFIG_FREERTOS_OPTIMIZED_SCHEDULER¶
Enable FreeRTOS pĺatform optimized scheduler
Found in: Component config > FreeRTOS
On most platforms there are instructions can speedup the ready task searching. Enabling this option the FreeRTOS with this instructions support will be built.
CONFIG_FREERTOS_HZ¶
Tick rate (Hz)
Found in: Component config > FreeRTOS
Select the tick rate at which FreeRTOS does pre-emptive context switching.
CONFIG_FREERTOS_ASSERT_ON_UNTESTED_FUNCTION¶
Halt when an SMP-untested function is called
Found in: Component config > FreeRTOS
Some functions in FreeRTOS have not been thoroughly tested yet when moving to the SMP implementation of FreeRTOS. When this option is enabled, these fuctions will throw an assert().
CONFIG_FREERTOS_CHECK_STACKOVERFLOW¶
Check for stack overflow
Found in: Component config > FreeRTOS
FreeRTOS can check for stack overflows in threads and trigger an user function called vApplicationStackOverflowHook when this happens.
- Available options:
No checking (FREERTOS_CHECK_STACKOVERFLOW_NONE)
Do not check for stack overflows (configCHECK_FOR_STACK_OVERFLOW=0)
Check by stack pointer value (FREERTOS_CHECK_STACKOVERFLOW_PTRVAL)
Check for stack overflows on each context switch by checking if the stack pointer is in a valid range. Quick but does not detect stack overflows that happened between context switches (configCHECK_FOR_STACK_OVERFLOW=1)
Check using canary bytes (FREERTOS_CHECK_STACKOVERFLOW_CANARY)
Places some magic bytes at the end of the stack area and on each context switch, check if these bytes are still intact. More thorough than just checking the pointer, but also slightly slower. (configCHECK_FOR_STACK_OVERFLOW=2)
CONFIG_FREERTOS_WATCHPOINT_END_OF_STACK¶
Set a debug watchpoint as a stack overflow check
Found in: Component config > FreeRTOS
FreeRTOS can check if a stack has overflown its bounds by checking either the value of the stack pointer or by checking the integrity of canary bytes. (See FREERTOS_CHECK_STACKOVERFLOW for more information.) These checks only happen on a context switch, and the situation that caused the stack overflow may already be long gone by then. This option will use the debug memory watchpoint 1 (the second one) to allow breaking into the debugger (or panic’ing) as soon as any of the last 32 bytes on the stack of a task are overwritten. The side effect is that using gdb, you effectively only have one watchpoint; the 2nd one is overwritten as soon as a task switch happens.
This check only triggers if the stack overflow writes within 4 bytes of the end of the stack, rather than overshooting further, so it is worth combining this approach with one of the other stack overflow check methods.
When this watchpoint is hit, gdb will stop with a SIGTRAP message. When no JTAG OCD is attached, esp-idf will panic on an unhandled debug exception.
CONFIG_FREERTOS_INTERRUPT_BACKTRACE¶
Enable backtrace from interrupt to task context
Found in: Component config > FreeRTOS
If this option is enabled, interrupt stack frame will be modified to point to the code of the interrupted task as its return address. This helps the debugger (or the panic handler) show a backtrace from the interrupt to the task which was interrupted. This also works for nested interrupts: higer level interrupt stack can be traced back to the lower level interrupt. This option adds 4 instructions to the interrupt dispatching code.
CONFIG_FREERTOS_THREAD_LOCAL_STORAGE_POINTERS¶
Number of thread local storage pointers
Found in: Component config > FreeRTOS
FreeRTOS has the ability to store per-thread pointers in the task control block. This controls the number of pointers available.
This value must be at least 1. Index 0 is reserved for use by the pthreads API thread-local-storage. Other indexes can be used for any desired purpose.
CONFIG_FREERTOS_ASSERT¶
FreeRTOS assertions
Found in: Component config > FreeRTOS
Failed FreeRTOS configASSERT() assertions can be configured to behave in different ways.
- Available options:
abort() on failed assertions (FREERTOS_ASSERT_FAIL_ABORT)
If a FreeRTOS configASSERT() fails, FreeRTOS will abort() and halt execution. The panic handler can be configured to handle the outcome of an abort() in different ways.
Print and continue failed assertions (FREERTOS_ASSERT_FAIL_PRINT_CONTINUE)
If a FreeRTOS assertion fails, print it out and continue.
Disable FreeRTOS assertions (FREERTOS_ASSERT_DISABLE)
FreeRTOS configASSERT() will not be compiled into the binary.
CONFIG_FREERTOS_IDLE_TASK_STACKSIZE¶
Idle Task stack size
Found in: Component config > FreeRTOS
The idle task has its own stack, sized in bytes. The default size is enough for most uses. Size can be reduced to 768 bytes if no (or simple) FreeRTOS idle hooks are used and pthread local storage or FreeRTOS local storage cleanup callbacks are not used.
The stack size may need to be increased above the default if the app installs idle or thread local storage cleanup hooks that use a lot of stack memory.
CONFIG_FREERTOS_ISR_STACKSIZE¶
ISR stack size
Found in: Component config > FreeRTOS
The interrupt handlers have their own stack. The size of the stack can be defined here. Each processor has its own stack, so the total size occupied will be twice this.
CONFIG_FREERTOS_LEGACY_HOOKS¶
Use FreeRTOS legacy hooks
Found in: Component config > FreeRTOS
FreeRTOS offers a number of hooks/callback functions that are called when a timer tick happens, the idle thread runs etc. esp-idf replaces these by runtime registerable hooks using the esp_register_freertos_xxx_hook system, but for legacy reasons the old hooks can also still be enabled. Please enable this only if you have code that for some reason can’t be migrated to the esp_register_freertos_xxx_hook system.
CONFIG_FREERTOS_MAX_TASK_NAME_LEN¶
Maximum task name length
Found in: Component config > FreeRTOS
Changes the maximum task name length. Each task allocated will include this many bytes for a task name. Using a shorter value saves a small amount of RAM, a longer value allows more complex names.
For most uses, the default of 16 is OK.
CONFIG_FREERTOS_SUPPORT_STATIC_ALLOCATION¶
Enable FreeRTOS static allocation API
Found in: Component config > FreeRTOS
FreeRTOS gives the application writer the ability to instead provide the memory themselves, allowing the following objects to optionally be created without any memory being allocated dynamically:
Tasks
Software Timers (Daemon task is still dynamic. See documentation)
Queues
Event Groups
Binary Semaphores
Counting Semaphores
Recursive Semaphores
Mutexes
Whether it is preferable to use static or dynamic memory allocation is dependent on the application, and the preference of the application writer. Both methods have pros and cons, and both methods can be used within the same RTOS application.
Creating RTOS objects using statically allocated RAM has the benefit of providing the application writer with more control: RTOS objects can be placed at specific memory locations. The maximum RAM footprint can be determined at link time, rather than run time. The application writer does not need to concern themselves with graceful handling of memory allocation failures. It allows the RTOS to be used in applications that simply don’t allow any dynamic memory allocation (although FreeRTOS includes allocation schemes that can overcome most objections).
CONFIG_FREERTOS_ENABLE_STATIC_TASK_CLEAN_UP¶
Enable static task clean up hook
Found in: Component config > FreeRTOS > CONFIG_FREERTOS_SUPPORT_STATIC_ALLOCATION
Enable this option to make FreeRTOS call the static task clean up hook when a task is deleted.
Bear in mind that if this option is enabled you will need to implement the following function:
void vPortCleanUpTCB ( void \*pxTCB ) { // place clean up code here }
CONFIG_FREERTOS_TIMER_TASK_PRIORITY¶
FreeRTOS timer task priority
Found in: Component config > FreeRTOS
The timer service task (primarily) makes use of existing FreeRTOS features, allowing timer functionality to be added to an application with minimal impact on the size of the application’s executable binary.
Use this constant to define the priority that the timer task will run at.
CONFIG_FREERTOS_TIMER_TASK_STACK_DEPTH¶
FreeRTOS timer task stack size
Found in: Component config > FreeRTOS
The timer service task (primarily) makes use of existing FreeRTOS features, allowing timer functionality to be added to an application with minimal impact on the size of the application’s executable binary.
Use this constant to define the size (in bytes) of the stack allocated for the timer task.
CONFIG_FREERTOS_TIMER_QUEUE_LENGTH¶
FreeRTOS timer queue length
Found in: Component config > FreeRTOS
FreeRTOS provides a set of timer related API functions. Many of these functions use a standard FreeRTOS queue to send commands to the timer service task. The queue used for this purpose is called the ‘timer command queue’. The ‘timer command queue’ is private to the FreeRTOS timer implementation, and cannot be accessed directly.
For most uses the default value of 10 is OK.
CONFIG_FREERTOS_QUEUE_REGISTRY_SIZE¶
FreeRTOS queue registry size
Found in: Component config > FreeRTOS
FreeRTOS uses the queue registry as a means for kernel aware debuggers to locate queues, semaphores, and mutexes. The registry allows for a textual name to be associated with a queue for easy identification within a debugging GUI. A value of 0 will disable queue registry functionality, and a value larger than 0 will specify the number of queues/semaphores/mutexes that the registry can hold.
CONFIG_FREERTOS_USE_TRACE_FACILITY¶
Enable FreeRTOS trace facility
Found in: Component config > FreeRTOS
If enabled, configUSE_TRACE_FACILITY will be defined as 1 in FreeRTOS. This will allow the usage of trace facility functions such as uxTaskGetSystemState().
CONFIG_FREERTOS_USE_STATS_FORMATTING_FUNCTIONS¶
Enable FreeRTOS stats formatting functions
Found in: Component config > FreeRTOS > CONFIG_FREERTOS_USE_TRACE_FACILITY
If enabled, configUSE_STATS_FORMATTING_FUNCTIONS will be defined as 1 in FreeRTOS. This will allow the usage of stats formatting functions such as vTaskList().
CONFIG_FREERTOS_VTASKLIST_INCLUDE_COREID¶
Enable display of xCoreID in vTaskList
Found in: Component config > FreeRTOS > CONFIG_FREERTOS_USE_TRACE_FACILITY > CONFIG_FREERTOS_USE_STATS_FORMATTING_FUNCTIONS
If enabled, this will include an extra column when vTaskList is called to display the CoreID the task is pinned to (0,1) or -1 if not pinned.
CONFIG_FREERTOS_GENERATE_RUN_TIME_STATS¶
Enable FreeRTOS to collect run time stats
Found in: Component config > FreeRTOS
If enabled, configGENERATE_RUN_TIME_STATS will be defined as 1 in FreeRTOS. This will allow FreeRTOS to collect information regarding the usage of processor time amongst FreeRTOS tasks. Run time stats are generated using either the ESP Timer or the CPU Clock as the clock source (Note that run time stats are only valid until the clock source overflows). The function vTaskGetRunTimeStats() will also be available if FREERTOS_USE_STATS_FORMATTING_FUNCTIONS and FREERTOS_USE_TRACE_FACILITY are enabled. vTaskGetRunTimeStats() will display the run time of each task as a % of the total run time of all CPUs (task run time / no of CPUs) / (total run time / 100 )
CONFIG_FREERTOS_RUN_TIME_STATS_CLK¶
Choose the clock source for run time stats
Found in: Component config > FreeRTOS > CONFIG_FREERTOS_GENERATE_RUN_TIME_STATS
Choose the clock source for FreeRTOS run time stats. Options are CPU0’s CPU Clock or the ESP Timer. Both clock sources are 32 bits. The CPU Clock can run at a higher frequency hence provide a finer resolution but will overflow much quicker. Note that run time stats are only valid until the clock source overflows.
- Available options:
Use ESP TIMER for run time stats (FREERTOS_RUN_TIME_STATS_USING_ESP_TIMER)
ESP Timer will be used as the clock source for FreeRTOS run time stats. The ESP Timer runs at a frequency of 1MHz regardless of Dynamic Frequency Scaling. Therefore the ESP Timer will overflow in approximately 4290 seconds.
Use CPU Clock for run time stats (FREERTOS_RUN_TIME_STATS_USING_CPU_CLK)
CPU Clock will be used as the clock source for the generation of run time stats. The CPU Clock has a frequency dependent on ESP32_DEFAULT_CPU_FREQ_MHZ and Dynamic Frequency Scaling (DFS). Therefore the CPU Clock frequency can fluctuate between 80 to 240MHz. Run time stats generated using the CPU Clock represents the number of CPU cycles each task is allocated and DOES NOT reflect the amount of time each task runs for (as CPU clock frequency can change). If the CPU clock consistently runs at the maximum frequency of 240MHz, it will overflow in approximately 17 seconds.
CONFIG_FREERTOS_USE_TICKLESS_IDLE¶
Tickless idle support
Found in: Component config > FreeRTOS
If power management support is enabled, FreeRTOS will be able to put the system into light sleep mode when no tasks need to run for a number of ticks. This number can be set using FREERTOS_IDLE_TIME_BEFORE_SLEEP option. This feature is also known as “automatic light sleep”.
Note that timers created using esp_timer APIs may prevent the system from entering sleep mode, even when no tasks need to run.
If disabled, automatic light sleep support will be disabled.
CONFIG_FREERTOS_IDLE_TIME_BEFORE_SLEEP¶
Minimum number of ticks to enter sleep mode for
Found in: Component config > FreeRTOS > CONFIG_FREERTOS_USE_TICKLESS_IDLE
FreeRTOS will enter light sleep mode if no tasks need to run for this number of ticks.
CONFIG_FREERTOS_TASK_FUNCTION_WRAPPER¶
Enclose all task functions in a wrapper function
Found in: Component config > FreeRTOS
If enabled, all FreeRTOS task functions will be enclosed in a wrapper function. If a task function mistakenly returns (i.e. does not delete), the call flow will return to the wrapper function. The wrapper function will then log an error and abort the application. This option is also required for GDB backtraces and C++ exceptions to work correctly inside top-level task functions.
CONFIG_FREERTOS_CHECK_MUTEX_GIVEN_BY_OWNER¶
Check that mutex semaphore is given by owner task
Found in: Component config > FreeRTOS
If enabled, assert that when a mutex semaphore is given, the task giving the semaphore is the task which is currently holding the mutex.
CONFIG_FREERTOS_CHECK_PORT_CRITICAL_COMPLIANCE¶
Tests compliance with Vanilla FreeRTOS port*_CRITICAL calls
Found in: Component config > FreeRTOS
If enabled, context of port*_CRITICAL calls (ISR or Non-ISR) would be checked to be in compliance with Vanilla FreeRTOS. e.g Calling port*_CRITICAL from ISR context would cause assert failure
ESP HTTPS OTA¶
Contains:
CONFIG_OTA_ALLOW_HTTP¶
Allow HTTP for OTA (WARNING: ONLY FOR TESTING PURPOSE, READ HELP)
Found in: Component config > ESP HTTPS OTA
It is highly recommended to keep HTTPS (along with server certificate validation) enabled. Enabling this option comes with potential risk of: - Non-encrypted communication channel with server - Accepting firmware upgrade image from server with fake identity
OpenSSL¶
Contains:
CONFIG_OPENSSL_DEBUG¶
Enable OpenSSL debugging
Found in: Component config > OpenSSL
Enable OpenSSL debugging function.
If the option is enabled, “SSL_DEBUG” works.
CONFIG_OPENSSL_DEBUG_LEVEL¶
OpenSSL debugging level
Found in: Component config > OpenSSL > CONFIG_OPENSSL_DEBUG
OpenSSL debugging level.
Only function whose debugging level is higher than “OPENSSL_DEBUG_LEVEL” works.
For example: If OPENSSL_DEBUG_LEVEL = 2, you use function “SSL_DEBUG(1, “malloc failed”)”. Because 1 < 2, it will not print.
CONFIG_OPENSSL_LOWLEVEL_DEBUG¶
Enable OpenSSL low-level module debugging
Found in: Component config > OpenSSL > CONFIG_OPENSSL_DEBUG
If the option is enabled, low-level module debugging function of OpenSSL is enabled, e.g. mbedtls internal debugging function.
CONFIG_OPENSSL_ASSERT¶
Select OpenSSL assert function
Found in: Component config > OpenSSL
OpenSSL function needs “assert” function to check if input parameters are valid.
If you want to use assert debugging function, “OPENSSL_DEBUG” should be enabled.
- Available options:
Do nothing (OPENSSL_ASSERT_DO_NOTHING)
Do nothing and “SSL_ASSERT” does not work.
Check and exit (OPENSSL_ASSERT_EXIT)
Enable assert exiting, it will check and return error code.
Show debugging message (OPENSSL_ASSERT_DEBUG)
Enable assert debugging, it will check and show debugging message.
Show debugging message and exit (OPENSSL_ASSERT_DEBUG_EXIT)
Enable assert debugging and exiting, it will check, show debugging message and return error code.
Show debugging message and block (OPENSSL_ASSERT_DEBUG_BLOCK)
Enable assert debugging and blocking, it will check, show debugging message and block by “while (1);”.
TinyUSB¶
Contains:
Descriptor configuration¶
Contains:
CONFIG_USB_DESC_USE_ESPRESSIF_VID¶
VID: Use an Espressif’s default value
Found in: Component config > TinyUSB > Descriptor configuration
Long description
CONFIG_USB_DESC_CUSTOM_VID¶
CONFIG_USB_DESC_USE_DEFAULT_PID¶
PID: Use a default PID assigning
Found in: Component config > TinyUSB > Descriptor configuration
Default TinyUSB PID assigning uses values 0x4000…0x4007
CONFIG_USB_DESC_CUSTOM_PID¶
CONFIG_USB_DESC_BCDDEVICE¶
bcdDevice
Found in: Component config > TinyUSB > Descriptor configuration
Version of the firmware of the USB device
CONFIG_USB_DESC_MANUFACTURER_STRING¶
Manufacturer
Found in: Component config > TinyUSB > Descriptor configuration
Name of the manufacturer of the USB device
CONFIG_USB_DESC_PRODUCT_STRING¶
CONFIG_USB_DESC_SERIAL_STRING¶
Serial string
Found in: Component config > TinyUSB > Descriptor configuration
Specify serial number of the USB device
libsodium¶
Contains:
CONFIG_LIBSODIUM_USE_MBEDTLS_SHA¶
Use mbedTLS SHA256 & SHA512 implementations
Found in: Component config > libsodium
If this option is enabled, libsodium will use thin wrappers around mbedTLS for SHA256 & SHA512 operations.
This saves some code size if mbedTLS is also used. However it is incompatible with hardware SHA acceleration (due to the way libsodium’s API manages SHA state).
ESP-TLS¶
Contains:
CONFIG_ESP_TLS_LIBRARY_CHOOSE¶
Choose SSL/TLS library for ESP-TLS (See help for more Info)
Found in: Component config > ESP-TLS
The ESP-TLS APIs support multiple backend TLS libraries. Currently mbedTLS and WolfSSL are supported. Different TLS libraries may support different features and have different resource usage. Consult the ESP-TLS documentation in ESP-IDF Programming guide for more details.
- Available options:
mbedTLS (ESP_TLS_USING_MBEDTLS)
wolfSSL (License info in wolfSSL directory README) (ESP_TLS_USING_WOLFSSL)
CONFIG_ESP_TLS_SERVER¶
Enable ESP-TLS Server
Found in: Component config > ESP-TLS
Enable support for creating server side SSL/TLS session, available for mbedTLS as well as wolfSSL TLS library.
CONFIG_ESP_TLS_PSK_VERIFICATION¶
Enable PSK verification
Found in: Component config > ESP-TLS
Enable support for pre shared key ciphers, supported for both mbedTLS as well as wolfSSL TLS library.
CONFIG_ESP_WOLFSSL_SMALL_CERT_VERIFY¶
Enable SMALL_CERT_VERIFY
Found in: Component config > ESP-TLS
Enables server verification with Intermediate CA cert, does not authenticate full chain of trust upto the root CA cert (After Enabling this option client only needs to have Intermediate CA certificate of the server to authenticate server, root CA cert is not necessary).
CONFIG_ESP_DEBUG_WOLFSSL¶
Enable debug logs for wolfSSL
Found in: Component config > ESP-TLS
Enable detailed debug prints for wolfSSL SSL library.
ESP NETIF Adapter¶
Contains:
CONFIG_ESP_NETIF_IP_LOST_TIMER_INTERVAL¶
IP Address lost timer interval (seconds)
Found in: Component config > ESP NETIF Adapter
The value of 0 indicates the IP lost timer is disabled, otherwise the timer is enabled.
The IP address may be lost because of some reasons, e.g. when the station disconnects from soft-AP, or when DHCP IP renew fails etc. If the IP lost timer is enabled, it will be started everytime the IP is lost. Event SYSTEM_EVENT_STA_LOST_IP will be raised if the timer expires. The IP lost timer is stopped if the station get the IP again before the timer expires.
CONFIG_ESP_NETIF_USE_TCPIP_STACK_LIB¶
TCP/IP Stack Library
Found in: Component config > ESP NETIF Adapter
Choose the TCP/IP Stack to work, for example, LwIP, uIP, etc.
- Available options:
LwIP (ESP_NETIF_TCPIP_LWIP)
lwIP is a small independent implementation of the TCP/IP protocol suite.
Loopback (ESP_NETIF_LOOPBACK)
Dummy implementation of esp-netif functionality which connects driver transmit to receive function. This option is for testing purpose only
CONFIG_ESP_NETIF_TCPIP_ADAPTER_COMPATIBLE_LAYER¶
Enable backward compatible tcpip_adapter interface
Found in: Component config > ESP NETIF Adapter
Backward compatible interface to tcpip_adapter is enabled by default to support legacy TCP/IP stack initialisation code. Disable this option to use only esp-netif interface.
jsmn¶
Contains:
CONFIG_JSMN_PARENT_LINKS¶
CONFIG_JSMN_STRICT¶
Enable strict mode
Found in: Component config > jsmn
In strict mode primitives are: numbers and booleans
mDNS¶
Contains:
CONFIG_MDNS_MAX_SERVICES¶
Max number of services
Found in: Component config > mDNS
Services take up a certain amount of memory, and allowing fewer services to be open at the same time conserves memory. Specify the maximum amount of services here. The valid value is from 1 to 64.
CONFIG_MDNS_TASK_PRIORITY¶
mDNS task priority
Found in: Component config > mDNS
Allows setting mDNS task priority. Please do not set the task priority higher than priorities of system tasks. Compile time warning/error would be emitted if the chosen task priority were too high.
CONFIG_MDNS_TASK_STACK_SIZE¶
CONFIG_MDNS_TASK_AFFINITY¶
mDNS task affinity
Found in: Component config > mDNS
Allows setting mDNS tasks affinity, i.e. whether the task is pinned to CPU0, pinned to CPU1, or allowed to run on any CPU.
- Available options:
No affinity (MDNS_TASK_AFFINITY_NO_AFFINITY)
CPU0 (MDNS_TASK_AFFINITY_CPU0)
CPU1 (MDNS_TASK_AFFINITY_CPU1)
CONFIG_MDNS_SERVICE_ADD_TIMEOUT_MS¶
mDNS adding service timeout (ms)
Found in: Component config > mDNS
Configures timeout for adding a new mDNS service. Adding a service fails if could not be completed within this time.
CONFIG_MDNS_STRICT_MODE¶
mDNS strict mode
Found in: Component config > mDNS
Configures strict mode. Set this to 1 for the mDNS library to strictly follow the RFC6762: Currently the only strict feature: Do not repeat original questions in response packets (defined in RFC6762 sec. 6). Default configuration is 0, i.e. non-strict mode, since some implementations, such as lwIP mdns resolver (used by standard POSIX API like getaddrinfo, gethostbyname) could not correctly resolve advertised names.
CONFIG_MDNS_TIMER_PERIOD_MS¶
mDNS timer period (ms)
Found in: Component config > mDNS
Configures period of mDNS timer, which periodically transmits packets and schedules mDNS searches.
Ethernet¶
Contains:
CONFIG_ETH_USE_SPI_ETHERNET¶
Support SPI to Ethernet Module
Found in: Component config > Ethernet
ESP-IDF can also support some SPI-Ethernet modules.
Contains:
CONFIG_ETH_SPI_ETHERNET_DM9051¶
Use DM9051
Found in: Component config > Ethernet > CONFIG_ETH_USE_SPI_ETHERNET
DM9051 is a fast Ethernet controller with an SPI interface. It’s also integrated with a 10/100M PHY and MAC. Select to enable DM9051 driver.
CONFIG_ETH_USE_OPENETH¶
Support OpenCores Ethernet MAC (for use with QEMU)
Found in: Component config > Ethernet
OpenCores Ethernet MAC driver can be used when an ESP-IDF application is executed in QEMU. This driver is not supported when running on a real chip.
Contains:
CONFIG_ETH_OPENETH_DMA_RX_BUFFER_NUM¶
Number of Ethernet DMA Rx buffers
Found in: Component config > Ethernet > CONFIG_ETH_USE_OPENETH
Number of DMA receive buffers, each buffer is 1600 bytes.
CONFIG_ETH_OPENETH_DMA_TX_BUFFER_NUM¶
Number of Ethernet DMA Tx buffers
Found in: Component config > Ethernet > CONFIG_ETH_USE_OPENETH
Number of DMA transmit buffers, each buffer is 1600 bytes.
GDB Stub¶
Contains:
CONFIG_ESP_GDBSTUB_SUPPORT_TASKS¶
Enable listing FreeRTOS tasks through GDB Stub
Found in: Component config > GDB Stub
If enabled, GDBStub can supply the list of FreeRTOS tasks to GDB. Thread list can be queried from GDB using ‘info threads’ command. Note that if GDB task lists were corrupted, this feature may not work. If GDBStub fails, try disabling this feature.
CONFIG_ESP_GDBSTUB_MAX_TASKS¶
Maximum number of tasks supported by GDB Stub
Found in: Component config > GDB Stub > CONFIG_ESP_GDBSTUB_SUPPORT_TASKS
Set the number of tasks which GDB Stub will support.
Wi-Fi Provisioning Manager¶
Contains:
CONFIG_WIFI_PROV_SCAN_MAX_ENTRIES¶
Max Wi-Fi Scan Result Entries
Found in: Component config > Wi-Fi Provisioning Manager
This sets the maximum number of entries of Wi-Fi scan results that will be kept by the provisioning manager
CONFIG_WIFI_PROV_AUTOSTOP_TIMEOUT¶
Provisioning auto-stop timeout
Found in: Component config > Wi-Fi Provisioning Manager
Time (in seconds) after which the Wi-Fi provisioning manager will auto-stop after connecting to a Wi-Fi network successfully.
Driver configurations¶
Contains:
ADC configuration¶
Contains:
CONFIG_ADC_FORCE_XPD_FSM¶
Use the FSM to control ADC power
Found in: Component config > Driver configurations > ADC configuration
ADC power can be controlled by the FSM instead of software. This allows the ADC to be shut off when it is not working leading to lower power consumption. However using the FSM control ADC power will increase the noise of ADC.
CONFIG_ADC_DISABLE_DAC¶
Disable DAC when ADC2 is used on GPIO 25 and 26
Found in: Component config > Driver configurations > ADC configuration
If this is set, the ADC2 driver will disable the output of the DAC corresponding to the specified channel. This is the default value.
For testing, disable this option so that we can measure the output of DAC by internal ADC.
SPI configuration¶
Contains:
CONFIG_SPI_MASTER_IN_IRAM¶
Place transmitting functions of SPI master into IRAM
Found in: Component config > Driver configurations > SPI configuration
Normally only the ISR of SPI master is placed in the IRAM, so that it can work without the flash when interrupt is triggered. For other functions, there’s some possibility that the flash cache miss when running inside and out of SPI functions, which may increase the interval of SPI transactions. Enable this to put
queue\_trans,get\_trans\_resultandtransmitfunctions into the IRAM to avoid possible cache miss.During unit test, this is enabled to measure the ideal case of api.
CONFIG_SPI_MASTER_ISR_IN_IRAM¶
Place SPI master ISR function into IRAM
Found in: Component config > Driver configurations > SPI configuration
Place the SPI master ISR in to IRAM to avoid possible cache miss.
Also you can forbid the ISR being disabled during flash writing access, by add ESP_INTR_FLAG_IRAM when initializing the driver.
CONFIG_SPI_SLAVE_IN_IRAM¶
Place transmitting functions of SPI slave into IRAM
Found in: Component config > Driver configurations > SPI configuration
Normally only the ISR of SPI slave is placed in the IRAM, so that it can work without the flash when interrupt is triggered. For other functions, there’s some possibility that the flash cache miss when running inside and out of SPI functions, which may increase the interval of SPI transactions. Enable this to put
queue\_trans,get\_trans\_resultandtransmitfunctions into the IRAM to avoid possible cache miss.
CONFIG_SPI_SLAVE_ISR_IN_IRAM¶
Place SPI slave ISR function into IRAM
Found in: Component config > Driver configurations > SPI configuration
Place the SPI slave ISR in to IRAM to avoid possible cache miss.
Also you can forbid the ISR being disabled during flash writing access, by add ESP_INTR_FLAG_IRAM when initializing the driver.
TWAI configuration¶
Contains:
CONFIG_TWAI_ISR_IN_IRAM¶
Place TWAI ISR function into IRAM
Found in: Component config > Driver configurations > TWAI configuration
Place the TWAI ISR in to IRAM. This will allow the ISR to avoid cache misses, and also be able to run whilst the cache is disabled (such as when writing to SPI Flash). Note that if this option is enabled: - Users should also set the ESP_INTR_FLAG_IRAM in the driver configuration structure when installing the driver (see docs for specifics). - Alert logging (i.e., setting of the TWAI_ALERT_AND_LOG flag) will have no effect.
CONFIG_TWAI_ERRATA_FIX_LISTEN_ONLY_DOM¶
Add SW workaround for listen only transmits dominant bit errata
Found in: Component config > Driver configurations > TWAI configuration
When in the listen only mode, the TWAI controller must not influence the TWAI bus (i.e., must not send any dominant bits). However, while in listen only mode on the ESP32/ESP32-S2/ESP32-S3/ESP32-C3, the TWAI controller will still transmit dominant bits when it detects an error (i.e., as part of an active error frame). Enabling this option will add a workaround that forces the TWAI controller into an error passive state on initialization, thus preventing any dominant bits from being sent.
UART configuration¶
Contains:
CONFIG_UART_ISR_IN_IRAM¶
Place UART ISR function into IRAM
Found in: Component config > Driver configurations > UART configuration
If this option is not selected, UART interrupt will be disabled for a long time and may cause data lost when doing spi flash operation.
eFuse Bit Manager¶
Contains:
CONFIG_EFUSE_CUSTOM_TABLE¶
Use custom eFuse table
Found in: Component config > eFuse Bit Manager
Allows to generate a structure for eFuse from the CSV file.
CONFIG_EFUSE_CUSTOM_TABLE_FILENAME¶
Custom eFuse CSV file
Found in: Component config > eFuse Bit Manager > CONFIG_EFUSE_CUSTOM_TABLE
Name of the custom eFuse CSV filename. This path is evaluated relative to the project root directory.
CONFIG_EFUSE_VIRTUAL¶
Simulate eFuse operations in RAM
Found in: Component config > eFuse Bit Manager
All read and writes operations are redirected to RAM instead of eFuse registers. If this option is set, all permanent changes (via eFuse) are disabled. Log output will state changes which would be applied, but they will not be.
ESP32S2-specific¶
Contains:
CONFIG_ESP32S2_DEFAULT_CPU_FREQ_MHZ¶
CPU frequency
Found in: Component config > ESP32S2-specific
CPU frequency to be set on application startup.
- Available options:
FPGA (ESP32S2_DEFAULT_CPU_FREQ_FPGA)
80 MHz (ESP32S2_DEFAULT_CPU_FREQ_80)
160 MHz (ESP32S2_DEFAULT_CPU_FREQ_160)
240 MHz (ESP32S2_DEFAULT_CPU_FREQ_240)
Memory protection¶
Contains:
CONFIG_ESP32S2_MEMPROT_FEATURE¶
Enable memory protection
Found in: Component config > ESP32S2-specific > Memory protection
If enabled, permission control module watches all memory access and fires panic handler if permission violation is detected. This feature automatically splits memory into data and instruction segments and sets Read/Execute permissions for instruction part (below splitting address) and Read/Write permissions for data part (above splitting address). The memory protection is effective on all access through IRAM0 and DRAM0 buses.
CONFIG_ESP32S2_MEMPROT_FEATURE_LOCK¶
Lock memory protection settings
Found in: Component config > ESP32S2-specific > Memory protection > CONFIG_ESP32S2_MEMPROT_FEATURE
Once locked, memory protection settings cannot be changed anymore. The lock is reset only on the chip startup.
Cache config¶
Contains:
CONFIG_ESP32S2_INSTRUCTION_CACHE_SIZE¶
Instruction cache size
Found in: Component config > ESP32S2-specific > Cache config
Instruction cache size to be set on application startup. If you use 8KB instruction cache rather than 16KB instruction cache, then the other 8KB will be added to the heap.
- Available options:
8KB (ESP32S2_INSTRUCTION_CACHE_8KB)
16KB (ESP32S2_INSTRUCTION_CACHE_16KB)
CONFIG_ESP32S2_INSTRUCTION_CACHE_LINE_SIZE¶
Instruction cache line size
Found in: Component config > ESP32S2-specific > Cache config
Instruction cache line size to be set on application startup.
- Available options:
16 Bytes (ESP32S2_INSTRUCTION_CACHE_LINE_16B)
32 Bytes (ESP32S2_INSTRUCTION_CACHE_LINE_32B)
CONFIG_ESP32S2_DATA_CACHE_SIZE¶
Data cache size
Found in: Component config > ESP32S2-specific > Cache config
Data cache size to be set on application startup. If you use 8KB data cache rather than 16KB data cache, the other 8KB will be added to the heap.
- Available options:
0KB (ESP32S2_DATA_CACHE_0KB)
8KB (ESP32S2_DATA_CACHE_8KB)
16KB (ESP32S2_DATA_CACHE_16KB)
CONFIG_ESP32S2_DATA_CACHE_LINE_SIZE¶
Data cache line size
Found in: Component config > ESP32S2-specific > Cache config
Data cache line size to be set on application startup.
- Available options:
16 Bytes (ESP32S2_DATA_CACHE_LINE_16B)
32 Bytes (ESP32S2_DATA_CACHE_LINE_32B)
CONFIG_ESP32S2_INSTRUCTION_CACHE_WRAP¶
Enable instruction cache wrap
Found in: Component config > ESP32S2-specific > Cache config
If enabled, instruction cache will use wrap mode to read spi flash (maybe spiram). The wrap length equals to INSTRUCTION_CACHE_LINE_SIZE. However, it depends on complex conditions.
CONFIG_ESP32S2_DATA_CACHE_WRAP¶
Enable data cache wrap
Found in: Component config > ESP32S2-specific > Cache config
If enabled, data cache will use wrap mode to read spiram (maybe spi flash). The wrap length equals to DATA_CACHE_LINE_SIZE. However, it depends on complex conditions.
CONFIG_ESP32S2_SPIRAM_SUPPORT¶
Support for external, SPI-connected RAM
Found in: Component config > ESP32S2-specific
This enables support for an external SPI RAM chip, connected in parallel with the main SPI flash chip.
SPI RAM config¶
Contains:
CONFIG_SPIRAM_TYPE¶
Type of SPI RAM chip in use
Found in: Component config > ESP32S2-specific > CONFIG_ESP32S2_SPIRAM_SUPPORT > SPI RAM config
- Available options:
Auto-detect (SPIRAM_TYPE_AUTO)
ESP-PSRAM16 or APS1604 (SPIRAM_TYPE_ESPPSRAM16)
ESP-PSRAM32 or IS25WP032 (SPIRAM_TYPE_ESPPSRAM32)
ESP-PSRAM64 or LY68L6400 (SPIRAM_TYPE_ESPPSRAM64)
CONFIG_SPIRAM_FETCH_INSTRUCTIONS¶
Cache fetch instructions from SPI RAM
Found in: Component config > ESP32S2-specific > CONFIG_ESP32S2_SPIRAM_SUPPORT > SPI RAM config
If enabled, instruction in flash will be copied into SPIRAM. If SPIRAM_RODATA also enabled, you can run the instruction when erasing or programming the flash.
CONFIG_SPIRAM_RODATA¶
Cache load read only data from SPI RAM
Found in: Component config > ESP32S2-specific > CONFIG_ESP32S2_SPIRAM_SUPPORT > SPI RAM config
If enabled, radata in flash will be copied into SPIRAM. If SPIRAM_FETCH_INSTRUCTIONS also enabled, you can run the instruction when erasing or programming the flash.
CONFIG_SPIRAM_USE_AHB_DBUS3¶
Enable AHB DBUS3 to access SPIRAM
Found in: Component config > ESP32S2-specific > CONFIG_ESP32S2_SPIRAM_SUPPORT > SPI RAM config
If Enabled, if SPI_CONFIG_SIZE is bigger then 10MB+576KB, then you can have 4MB more space to map the SPIRAM. However, the AHB bus is slower than other data cache buses.
CONFIG_SPIRAM_SPEED¶
Set RAM clock speed
Found in: Component config > ESP32S2-specific > CONFIG_ESP32S2_SPIRAM_SUPPORT > SPI RAM config
Select the speed for the SPI RAM chip. If SPI RAM is enabled, we only support three combinations of SPI speed mode we supported now:
Flash SPI running at 40Mhz and RAM SPI running at 40Mhz
Flash SPI running at 80Mhz and RAM SPI running at 40Mhz
Flash SPI running at 80Mhz and RAM SPI running at 80Mhz
Note: If the third mode(80Mhz+80Mhz) is enabled for SPI RAM of type 32MBit, one of the HSPI/VSPI host will be occupied by the system. Which SPI host to use can be selected by the config item SPIRAM_OCCUPY_SPI_HOST. Application code should never touch HSPI/VSPI hardware in this case. The option to select 80MHz will only be visible if the flash SPI speed is also 80MHz. (ESPTOOLPY_FLASHFREQ_80M is true)
- Available options:
80MHz clock speed (SPIRAM_SPEED_80M)
40Mhz clock speed (SPIRAM_SPEED_40M)
26Mhz clock speed (SPIRAM_SPEED_26M)
20Mhz clock speed (SPIRAM_SPEED_20M)
CONFIG_SPIRAM_BOOT_INIT¶
Initialize SPI RAM during startup
Found in: Component config > ESP32S2-specific > CONFIG_ESP32S2_SPIRAM_SUPPORT > SPI RAM config
If this is enabled, the SPI RAM will be enabled during initial boot. Unless you have specific requirements, you’ll want to leave this enabled so memory allocated during boot-up can also be placed in SPI RAM.
CONFIG_SPIRAM_IGNORE_NOTFOUND¶
Ignore PSRAM when not found
Found in: Component config > ESP32S2-specific > CONFIG_ESP32S2_SPIRAM_SUPPORT > SPI RAM config > CONFIG_SPIRAM_BOOT_INIT
Normally, if psram initialization is enabled during compile time but not found at runtime, it is seen as an error making the CPU panic. If this is enabled, booting will complete but no PSRAM will be available.
CONFIG_SPIRAM_USE¶
SPI RAM access method
Found in: Component config > ESP32S2-specific > CONFIG_ESP32S2_SPIRAM_SUPPORT > SPI RAM config
The SPI RAM can be accessed in multiple methods: by just having it available as an unmanaged memory region in the CPU’s memory map, by integrating it in the heap as ‘special’ memory needing heap_caps_malloc to allocate, or by fully integrating it making malloc() also able to return SPI RAM pointers.
- Available options:
Integrate RAM into memory map (SPIRAM_USE_MEMMAP)
Make RAM allocatable using heap_caps_malloc(…, MALLOC_CAP_SPIRAM) (SPIRAM_USE_CAPS_ALLOC)
Make RAM allocatable using malloc() as well (SPIRAM_USE_MALLOC)
CONFIG_SPIRAM_MEMTEST¶
Run memory test on SPI RAM initialization
Found in: Component config > ESP32S2-specific > CONFIG_ESP32S2_SPIRAM_SUPPORT > SPI RAM config
Runs a rudimentary memory test on initialization. Aborts when memory test fails. Disable this for slightly faster startup.
CONFIG_SPIRAM_MALLOC_ALWAYSINTERNAL¶
Maximum malloc() size, in bytes, to always put in internal memory
Found in: Component config > ESP32S2-specific > CONFIG_ESP32S2_SPIRAM_SUPPORT > SPI RAM config
If malloc() is capable of also allocating SPI-connected ram, its allocation strategy will prefer to allocate chunks less than this size in internal memory, while allocations larger than this will be done from external RAM. If allocation from the preferred region fails, an attempt is made to allocate from the non-preferred region instead, so malloc() will not suddenly fail when either internal or external memory is full.
CONFIG_SPIRAM_TRY_ALLOCATE_WIFI_LWIP¶
Try to allocate memories of WiFi and LWIP in SPIRAM firstly. If failed, allocate internal memory
Found in: Component config > ESP32S2-specific > CONFIG_ESP32S2_SPIRAM_SUPPORT > SPI RAM config
Try to allocate memories of WiFi and LWIP in SPIRAM firstly. If failed, try to allocate internal memory then.
CONFIG_SPIRAM_MALLOC_RESERVE_INTERNAL¶
Reserve this amount of bytes for data that specifically needs to be in DMA or internal memory
Found in: Component config > ESP32S2-specific > CONFIG_ESP32S2_SPIRAM_SUPPORT > SPI RAM config
Because the external/internal RAM allocation strategy is not always perfect, it sometimes may happen that the internal memory is entirely filled up. This causes allocations that are specifically done in internal memory, for example the stack for new tasks or memory to service DMA or have memory that’s also available when SPI cache is down, to fail. This option reserves a pool specifically for requests like that; the memory in this pool is not given out when a normal malloc() is called.
Set this to 0 to disable this feature.
Note that because FreeRTOS stacks are forced to internal memory, they will also use this memory pool; be sure to keep this in mind when adjusting this value.
Note also that the DMA reserved pool may not be one single contiguous memory region, depending on the configured size and the static memory usage of the app.
CONFIG_ESP32S2_TRAX¶
Use TRAX tracing feature
Found in: Component config > ESP32S2-specific
The ESP32S2 contains a feature which allows you to trace the execution path the processor has taken through the program. This is stored in a chunk of 32K (16K for single-processor) of memory that can’t be used for general purposes anymore. Disable this if you do not know what this is.
CONFIG_ESP32S2_UNIVERSAL_MAC_ADDRESSES¶
Number of universally administered (by IEEE) MAC address
Found in: Component config > ESP32S2-specific
Configure the number of universally administered (by IEEE) MAC addresses. During initialization, MAC addresses for each network interface are generated or derived from a single base MAC address. If the number of universal MAC addresses is Two, all interfaces (WiFi station, WiFi softap) receive a universally administered MAC address. They are generated sequentially by adding 0, and 1 (respectively) to the final octet of the base MAC address. If the number of universal MAC addresses is one, only WiFi station receives a universally administered MAC address. It’s generated by adding 0 to the base MAC address. The WiFi softap receives local MAC addresses. It’s derived from the universal WiFi station MAC addresses. When using the default (Espressif-assigned) base MAC address, either setting can be used. When using a custom universal MAC address range, the correct setting will depend on the allocation of MAC addresses in this range (either 1 or 2 per device.)
- Available options:
One (ESP32S2_UNIVERSAL_MAC_ADDRESSES_ONE)
Two (ESP32S2_UNIVERSAL_MAC_ADDRESSES_TWO)
CONFIG_ESP32S2_ULP_COPROC_ENABLED¶
Enable Ultra Low Power (ULP) Coprocessor
Found in: Component config > ESP32S2-specific
Set to ‘y’ if you plan to load a firmware for the coprocessor.
If this option is enabled, further coprocessor configuration will appear in the Components menu.
CONFIG_ESP32S2_ULP_COPROC_RESERVE_MEM¶
RTC slow memory reserved for coprocessor
Found in: Component config > ESP32S2-specific > CONFIG_ESP32S2_ULP_COPROC_ENABLED
Bytes of memory to reserve for ULP coprocessor firmware & data.
Data is reserved at the beginning of RTC slow memory.
CONFIG_ESP32S2_DEBUG_OCDAWARE¶
Make exception and panic handlers JTAG/OCD aware
Found in: Component config > ESP32S2-specific
The FreeRTOS panic and unhandled exception handers can detect a JTAG OCD debugger and instead of panicking, have the debugger stop on the offending instruction.
CONFIG_ESP32S2_DEBUG_STUBS_ENABLE¶
OpenOCD debug stubs
Found in: Component config > ESP32S2-specific
Debug stubs are used by OpenOCD to execute pre-compiled onboard code which does some useful debugging, e.g. GCOV data dump.
CONFIG_ESP32S2_BROWNOUT_DET¶
Hardware brownout detect & reset
Found in: Component config > ESP32S2-specific
The ESP32-S2 has a built-in brownout detector which can detect if the voltage is lower than a specific value. If this happens, it will reset the chip in order to prevent unintended behaviour.
CONFIG_ESP32S2_BROWNOUT_DET_LVL_SEL¶
Brownout voltage level
Found in: Component config > ESP32S2-specific > CONFIG_ESP32S2_BROWNOUT_DET
The brownout detector will reset the chip when the supply voltage is approximately below this level. Note that there may be some variation of brownout voltage level between each ESP3-S2 chip.
#The voltage levels here are estimates, more work needs to be done to figure out the exact voltages #of the brownout threshold levels.
- Available options:
2.44V (ESP32S2_BROWNOUT_DET_LVL_SEL_7)
2.56V (ESP32S2_BROWNOUT_DET_LVL_SEL_6)
2.67V (ESP32S2_BROWNOUT_DET_LVL_SEL_5)
2.84V (ESP32S2_BROWNOUT_DET_LVL_SEL_4)
2.98V (ESP32S2_BROWNOUT_DET_LVL_SEL_3)
3.19V (ESP32S2_BROWNOUT_DET_LVL_SEL_2)
3.30V (ESP32S2_BROWNOUT_DET_LVL_SEL_1)
CONFIG_ESP32S2_TIME_SYSCALL¶
Timers used for gettimeofday function
Found in: Component config > ESP32S2-specific
This setting defines which hardware timers are used to implement ‘gettimeofday’ and ‘time’ functions in C library.
If both high-resolution and RTC timers are used, timekeeping will continue in deep sleep. Time will be reported at 1 microsecond resolution. This is the default, and the recommended option.
If only high-resolution timer is used, gettimeofday will provide time at microsecond resolution. Time will not be preserved when going into deep sleep mode.
If only RTC timer is used, timekeeping will continue in deep sleep, but time will be measured at 6.(6) microsecond resolution. Also the gettimeofday function itself may take longer to run.
If no timers are used, gettimeofday and time functions return -1 and set errno to ENOSYS.
When RTC is used for timekeeping, two RTC_STORE registers are used to keep time in deep sleep mode.
- Available options:
RTC and high-resolution timer (ESP32S2_TIME_SYSCALL_USE_RTC_FRC1)
RTC (ESP32S2_TIME_SYSCALL_USE_RTC)
High-resolution timer (ESP32S2_TIME_SYSCALL_USE_FRC1)
None (ESP32S2_TIME_SYSCALL_USE_NONE)
CONFIG_ESP32S2_RTC_CLK_SRC¶
RTC clock source
Found in: Component config > ESP32S2-specific
Choose which clock is used as RTC clock source.
“Internal 90kHz oscillator” option provides lowest deep sleep current consumption, and does not require extra external components. However frequency stability with respect to temperature is poor, so time may drift in deep/light sleep modes.
“External 32kHz crystal” provides better frequency stability, at the expense of slightly higher (1uA) deep sleep current consumption.
“External 32kHz oscillator” allows using 32kHz clock generated by an external circuit. In this case, external clock signal must be connected to 32K_XN pin. Amplitude should be <1.2V in case of sine wave signal, and <1V in case of square wave signal. Common mode voltage should be 0.1 < Vcm < 0.5Vamp, where Vamp is the signal amplitude. Additionally, 1nF capacitor must be connected between 32K_XP pin and ground. 32K_XP pin can not be used as a GPIO in this case.
“Internal 8MHz oscillator divided by 256” option results in higher deep sleep current (by 5uA) but has better frequency stability than the internal 90kHz oscillator. It does not require external components.
- Available options:
Internal 90kHz RC oscillator (ESP32S2_RTC_CLK_SRC_INT_RC)
External 32kHz crystal (ESP32S2_RTC_CLK_SRC_EXT_CRYS)
External 32kHz oscillator at 32K_XN pin (ESP32S2_RTC_CLK_SRC_EXT_OSC)
Internal 8MHz oscillator, divided by 256 (~32kHz) (ESP32S2_RTC_CLK_SRC_INT_8MD256)
CONFIG_ESP32S2_RTC_CLK_CAL_CYCLES¶
Number of cycles for RTC_SLOW_CLK calibration
Found in: Component config > ESP32S2-specific
When the startup code initializes RTC_SLOW_CLK, it can perform calibration by comparing the RTC_SLOW_CLK frequency with main XTAL frequency. This option sets the number of RTC_SLOW_CLK cycles measured by the calibration routine. Higher numbers increase calibration precision, which may be important for applications which spend a lot of time in deep sleep. Lower numbers reduce startup time.
When this option is set to 0, clock calibration will not be performed at startup, and approximate clock frequencies will be assumed:
90000 Hz if internal RC oscillator is used as clock source. For this use value 1024.
32768 Hz if the 32k crystal oscillator is used. For this use value 3000 or more. In case more value will help improve the definition of the launch of the crystal. If the crystal could not start, it will be switched to internal RC.
CONFIG_ESP32S2_RTC_XTAL_CAL_RETRY¶
Number of attempts to repeat 32k XTAL calibration
Found in: Component config > ESP32S2-specific
Number of attempts to repeat 32k XTAL calibration before giving up and switching to the internal RC. Increase this option if the 32k crystal oscillator does not start and switches to internal RC.
CONFIG_ESP32S2_NO_BLOBS¶
No Binary Blobs
Found in: Component config > ESP32S2-specific
If enabled, this disables the linking of binary libraries in the application build. Note that after enabling this Wi-Fi/Bluetooth will not work.
CONFIG_ESP32S2_RTCDATA_IN_FAST_MEM¶
Place RTC_DATA_ATTR and RTC_RODATA_ATTR variables into RTC fast memory segment
Found in: Component config > ESP32S2-specific
This option allows to place .rtc_data and .rtc_rodata sections into RTC fast memory segment to free the slow memory region for ULP programs.
CONFIG_ESP32S2_ALLOW_RTC_FAST_MEM_AS_HEAP¶
Enable RTC fast memory for dynamic allocations
Found in: Component config > ESP32S2-specific
This config option allows to add RTC fast memory region to system heap with capability similar to that of DRAM region but without DMA. This memory will be consumed first per heap initialization order by early startup services and scheduler related code. Speed wise RTC fast memory operates on APB clock and hence does not have much performance impact.
Power Management¶
Contains:
CONFIG_PM_ENABLE¶
Support for power management
Found in: Component config > Power Management
If enabled, application is compiled with support for power management. This option has run-time overhead (increased interrupt latency, longer time to enter idle state), and it also reduces accuracy of RTOS ticks and timers used for timekeeping. Enable this option if application uses power management APIs.
CONFIG_PM_DFS_INIT_AUTO¶
Enable dynamic frequency scaling (DFS) at startup
Found in: Component config > Power Management > CONFIG_PM_ENABLE
If enabled, startup code configures dynamic frequency scaling. Max CPU frequency is set to CONFIG_ESP32S2_DEFAULT_CPU_FREQ_MHZ setting, min frequency is set to XTAL frequency. If disabled, DFS will not be active until the application configures it using esp_pm_configure function.
CONFIG_PM_USE_RTC_TIMER_REF¶
Use RTC timer to prevent time drift (EXPERIMENTAL)
Found in: Component config > Power Management > CONFIG_PM_ENABLE
When APB clock frequency changes, high-resolution timer (esp_timer) scale and base value need to be adjusted. Each adjustment may cause small error, and over time such small errors may cause time drift. If this option is enabled, RTC timer will be used as a reference to compensate for the drift. It is recommended that this option is only used if 32k XTAL is selected as RTC clock source.
CONFIG_PM_PROFILING¶
Enable profiling counters for PM locks
Found in: Component config > Power Management > CONFIG_PM_ENABLE
If enabled, esp_pm_* functions will keep track of the amount of time each of the power management locks has been held, and esp_pm_dump_locks function will print this information. This feature can be used to analyze which locks are preventing the chip from going into a lower power state, and see what time the chip spends in each power saving mode. This feature does incur some run-time overhead, so should typically be disabled in production builds.
CONFIG_PM_TRACE¶
Enable debug tracing of PM using GPIOs
Found in: Component config > Power Management > CONFIG_PM_ENABLE
If enabled, some GPIOs will be used to signal events such as RTOS ticks, frequency switching, entry/exit from idle state. Refer to pm_trace.c file for the list of GPIOs. This feature is intended to be used when analyzing/debugging behavior of power management implementation, and should be kept disabled in applications.
Compatibility options¶
Contains:
CONFIG_LEGACY_INCLUDE_COMMON_HEADERS¶
Include headers across components as before IDF v4.0
Found in: Compatibility options
Soc, esp32, and driver components, the most common components. Some header of these components are included implicitly by headers of other components before IDF v4.0. It’s not required for high-level components, but still included through long header chain everywhere.
This is harmful to the modularity. So it’s changed in IDF v4.0.
You can still include these headers in a legacy way until it is totally deprecated by enable this option.
Deprecated options and their replacements¶
CONFIG_ADC2_DISABLE_DAC (CONFIG_ADC_DISABLE_DAC)
CONFIG_APP_ANTI_ROLLBACK (CONFIG_BOOTLOADER_APP_ANTI_ROLLBACK)
CONFIG_APP_ROLLBACK_ENABLE (CONFIG_BOOTLOADER_APP_ROLLBACK_ENABLE)
CONFIG_APP_SECURE_VERSION (CONFIG_BOOTLOADER_APP_SECURE_VERSION)
CONFIG_APP_SECURE_VERSION_SIZE_EFUSE_FIELD (CONFIG_BOOTLOADER_APP_SEC_VER_SIZE_EFUSE_FIELD)
- CONFIG_CONSOLE_UART (CONFIG_ESP_CONSOLE_UART)
CONFIG_CONSOLE_UART_DEFAULT
CONFIG_CONSOLE_UART_CUSTOM
CONFIG_CONSOLE_UART_NONE
CONFIG_CONSOLE_UART_BAUDRATE (CONFIG_ESP_CONSOLE_UART_BAUDRATE)
- CONFIG_CONSOLE_UART_NUM (CONFIG_ESP_CONSOLE_UART_NUM)
CONFIG_CONSOLE_UART_CUSTOM_NUM_0
CONFIG_CONSOLE_UART_CUSTOM_NUM_1
CONFIG_CONSOLE_UART_RX_GPIO (CONFIG_ESP_CONSOLE_UART_RX_GPIO)
CONFIG_CONSOLE_UART_TX_GPIO (CONFIG_ESP_CONSOLE_UART_TX_GPIO)
CONFIG_CXX_EXCEPTIONS (CONFIG_COMPILER_CXX_EXCEPTIONS)
CONFIG_CXX_EXCEPTIONS_EMG_POOL_SIZE (CONFIG_COMPILER_CXX_EXCEPTIONS_EMG_POOL_SIZE)
CONFIG_DISABLE_GCC8_WARNINGS (CONFIG_COMPILER_DISABLE_GCC8_WARNINGS)
CONFIG_EFUSE_SECURE_VERSION_EMULATE (CONFIG_BOOTLOADER_EFUSE_SECURE_VERSION_EMULATE)
CONFIG_ENABLE_STATIC_TASK_CLEAN_UP_HOOK (CONFIG_FREERTOS_ENABLE_STATIC_TASK_CLEAN_UP)
- CONFIG_ESP32S2_PANIC (CONFIG_ESP_SYSTEM_PANIC)
CONFIG_ESP32S2_PANIC_PRINT_HALT
CONFIG_ESP32S2_PANIC_PRINT_REBOOT
CONFIG_ESP32S2_PANIC_SILENT_REBOOT
CONFIG_ESP32S2_PANIC_GDBSTUB
- CONFIG_ESP32_APPTRACE_DESTINATION (CONFIG_APPTRACE_DESTINATION)
CONFIG_ESP32_APPTRACE_DEST_TRAX
CONFIG_ESP32_APPTRACE_DEST_NONE
CONFIG_ESP32_APPTRACE_ONPANIC_HOST_FLUSH_TMO (CONFIG_APPTRACE_ONPANIC_HOST_FLUSH_TMO)
CONFIG_ESP32_APPTRACE_PENDING_DATA_SIZE_MAX (CONFIG_APPTRACE_PENDING_DATA_SIZE_MAX)
CONFIG_ESP32_APPTRACE_POSTMORTEM_FLUSH_TRAX_THRESH (CONFIG_APPTRACE_POSTMORTEM_FLUSH_THRESH)
CONFIG_ESP32_GCOV_ENABLE (CONFIG_APPTRACE_GCOV_ENABLE)
- CONFIG_ESP32_PANIC (CONFIG_ESP_SYSTEM_PANIC)
CONFIG_ESP32S2_PANIC_PRINT_HALT
CONFIG_ESP32S2_PANIC_PRINT_REBOOT
CONFIG_ESP32S2_PANIC_SILENT_REBOOT
CONFIG_ESP32S2_PANIC_GDBSTUB
CONFIG_ESP32_PTHREAD_STACK_MIN (CONFIG_PTHREAD_STACK_MIN)
- CONFIG_ESP32_PTHREAD_TASK_CORE_DEFAULT (CONFIG_PTHREAD_TASK_CORE_DEFAULT)
CONFIG_ESP32_DEFAULT_PTHREAD_CORE_NO_AFFINITY
CONFIG_ESP32_DEFAULT_PTHREAD_CORE_0
CONFIG_ESP32_DEFAULT_PTHREAD_CORE_1
CONFIG_ESP32_PTHREAD_TASK_NAME_DEFAULT (CONFIG_PTHREAD_TASK_NAME_DEFAULT)
CONFIG_ESP32_PTHREAD_TASK_PRIO_DEFAULT (CONFIG_PTHREAD_TASK_PRIO_DEFAULT)
CONFIG_ESP32_PTHREAD_TASK_STACK_SIZE_DEFAULT (CONFIG_PTHREAD_TASK_STACK_SIZE_DEFAULT)
CONFIG_ESP_GRATUITOUS_ARP (CONFIG_LWIP_ESP_GRATUITOUS_ARP)
CONFIG_ESP_TCP_KEEP_CONNECTION_WHEN_IP_CHANGES (CONFIG_LWIP_TCP_KEEP_CONNECTION_WHEN_IP_CHANGES)
CONFIG_EVENT_LOOP_PROFILING (CONFIG_ESP_EVENT_LOOP_PROFILING)
CONFIG_FLASH_ENCRYPTION_ENABLED (CONFIG_SECURE_FLASH_ENC_ENABLED)
CONFIG_FLASH_ENCRYPTION_UART_BOOTLOADER_ALLOW_CACHE (CONFIG_SECURE_FLASH_UART_BOOTLOADER_ALLOW_CACHE)
CONFIG_FLASH_ENCRYPTION_UART_BOOTLOADER_ALLOW_ENCRYPT (CONFIG_SECURE_FLASH_UART_BOOTLOADER_ALLOW_ENC)
CONFIG_GARP_TMR_INTERVAL (CONFIG_LWIP_GARP_TMR_INTERVAL)
CONFIG_GDBSTUB_MAX_TASKS (CONFIG_ESP_GDBSTUB_MAX_TASKS)
CONFIG_GDBSTUB_SUPPORT_TASKS (CONFIG_ESP_GDBSTUB_SUPPORT_TASKS)
CONFIG_INT_WDT (CONFIG_ESP_INT_WDT)
CONFIG_INT_WDT_CHECK_CPU1 (CONFIG_ESP_INT_WDT_CHECK_CPU1)
CONFIG_INT_WDT_TIMEOUT_MS (CONFIG_ESP_INT_WDT_TIMEOUT_MS)
CONFIG_IPC_TASK_STACK_SIZE (CONFIG_ESP_IPC_TASK_STACK_SIZE)
CONFIG_L2_TO_L3_COPY (CONFIG_LWIP_L2_TO_L3_COPY)
- CONFIG_LOG_BOOTLOADER_LEVEL (CONFIG_BOOTLOADER_LOG_LEVEL)
CONFIG_LOG_BOOTLOADER_LEVEL_NONE
CONFIG_LOG_BOOTLOADER_LEVEL_ERROR
CONFIG_LOG_BOOTLOADER_LEVEL_WARN
CONFIG_LOG_BOOTLOADER_LEVEL_INFO
CONFIG_LOG_BOOTLOADER_LEVEL_DEBUG
CONFIG_LOG_BOOTLOADER_LEVEL_VERBOSE
CONFIG_MAIN_TASK_STACK_SIZE (CONFIG_ESP_MAIN_TASK_STACK_SIZE)
CONFIG_MAKE_WARN_UNDEFINED_VARIABLES (CONFIG_SDK_MAKE_WARN_UNDEFINED_VARIABLES)
CONFIG_MB_CONTROLLER_NOTIFY_QUEUE_SIZE (CONFIG_FMB_CONTROLLER_NOTIFY_QUEUE_SIZE)
CONFIG_MB_CONTROLLER_NOTIFY_TIMEOUT (CONFIG_FMB_CONTROLLER_NOTIFY_TIMEOUT)
CONFIG_MB_CONTROLLER_SLAVE_ID (CONFIG_FMB_CONTROLLER_SLAVE_ID)
CONFIG_MB_CONTROLLER_SLAVE_ID_SUPPORT (CONFIG_FMB_CONTROLLER_SLAVE_ID_SUPPORT)
CONFIG_MB_CONTROLLER_STACK_SIZE (CONFIG_FMB_CONTROLLER_STACK_SIZE)
CONFIG_MB_EVENT_QUEUE_TIMEOUT (CONFIG_FMB_EVENT_QUEUE_TIMEOUT)
CONFIG_MB_MASTER_DELAY_MS_CONVERT (CONFIG_FMB_MASTER_DELAY_MS_CONVERT)
CONFIG_MB_MASTER_TIMEOUT_MS_RESPOND (CONFIG_FMB_MASTER_TIMEOUT_MS_RESPOND)
CONFIG_MB_QUEUE_LENGTH (CONFIG_FMB_QUEUE_LENGTH)
CONFIG_MB_SERIAL_BUF_SIZE (CONFIG_FMB_SERIAL_BUF_SIZE)
CONFIG_MB_SERIAL_TASK_PRIO (CONFIG_FMB_SERIAL_TASK_PRIO)
CONFIG_MB_SERIAL_TASK_STACK_SIZE (CONFIG_FMB_SERIAL_TASK_STACK_SIZE)
CONFIG_MB_TIMER_GROUP (CONFIG_FMB_TIMER_GROUP)
CONFIG_MB_TIMER_INDEX (CONFIG_FMB_TIMER_INDEX)
CONFIG_MB_TIMER_PORT_ENABLED (CONFIG_FMB_TIMER_PORT_ENABLED)
- CONFIG_MONITOR_BAUD (CONFIG_ESPTOOLPY_MONITOR_BAUD)
CONFIG_MONITOR_BAUD_9600B
CONFIG_MONITOR_BAUD_57600B
CONFIG_MONITOR_BAUD_115200B
CONFIG_MONITOR_BAUD_230400B
CONFIG_MONITOR_BAUD_921600B
CONFIG_MONITOR_BAUD_2MB
CONFIG_MONITOR_BAUD_OTHER
CONFIG_MONITOR_BAUD_OTHER_VAL (CONFIG_ESPTOOLPY_MONITOR_BAUD_OTHER_VAL)
- CONFIG_OPTIMIZATION_ASSERTION_LEVEL (CONFIG_COMPILER_OPTIMIZATION_ASSERTION_LEVEL)
CONFIG_OPTIMIZATION_ASSERTIONS_ENABLED
CONFIG_OPTIMIZATION_ASSERTIONS_SILENT
CONFIG_OPTIMIZATION_ASSERTIONS_DISABLED
- CONFIG_OPTIMIZATION_COMPILER (CONFIG_COMPILER_OPTIMIZATION)
CONFIG_COMPILER_OPTIMIZATION_LEVEL_DEBUG
CONFIG_COMPILER_OPTIMIZATION_LEVEL_RELEASE
CONFIG_POST_EVENTS_FROM_IRAM_ISR (CONFIG_ESP_EVENT_POST_FROM_IRAM_ISR)
CONFIG_POST_EVENTS_FROM_ISR (CONFIG_ESP_EVENT_POST_FROM_ISR)
CONFIG_PPP_CHAP_SUPPORT (CONFIG_LWIP_PPP_CHAP_SUPPORT)
CONFIG_PPP_DEBUG_ON (CONFIG_LWIP_PPP_DEBUG_ON)
CONFIG_PPP_MPPE_SUPPORT (CONFIG_LWIP_PPP_MPPE_SUPPORT)
CONFIG_PPP_MSCHAP_SUPPORT (CONFIG_LWIP_PPP_MSCHAP_SUPPORT)
CONFIG_PPP_NOTIFY_PHASE_SUPPORT (CONFIG_LWIP_PPP_NOTIFY_PHASE_SUPPORT)
CONFIG_PPP_PAP_SUPPORT (CONFIG_LWIP_PPP_PAP_SUPPORT)
CONFIG_PPP_SUPPORT (CONFIG_LWIP_PPP_SUPPORT)
CONFIG_PYTHON (CONFIG_SDK_PYTHON)
CONFIG_SEMIHOSTFS_HOST_PATH_MAX_LEN (CONFIG_VFS_SEMIHOSTFS_HOST_PATH_MAX_LEN)
CONFIG_SEMIHOSTFS_MAX_MOUNT_POINTS (CONFIG_VFS_SEMIHOSTFS_MAX_MOUNT_POINTS)
- CONFIG_SPI_FLASH_WRITING_DANGEROUS_REGIONS (CONFIG_SPI_FLASH_DANGEROUS_WRITE)
CONFIG_SPI_FLASH_WRITING_DANGEROUS_REGIONS_ABORTS
CONFIG_SPI_FLASH_WRITING_DANGEROUS_REGIONS_FAILS
CONFIG_SPI_FLASH_WRITING_DANGEROUS_REGIONS_ALLOWED
- CONFIG_STACK_CHECK_MODE (CONFIG_COMPILER_STACK_CHECK_MODE)
CONFIG_STACK_CHECK_NONE
CONFIG_STACK_CHECK_NORM
CONFIG_STACK_CHECK_STRONG
CONFIG_STACK_CHECK_ALL
CONFIG_SUPPORT_STATIC_ALLOCATION (CONFIG_FREERTOS_SUPPORT_STATIC_ALLOCATION)
CONFIG_SUPPORT_TERMIOS (CONFIG_VFS_SUPPORT_TERMIOS)
CONFIG_SUPPRESS_SELECT_DEBUG_OUTPUT (CONFIG_VFS_SUPPRESS_SELECT_DEBUG_OUTPUT)
CONFIG_SYSTEM_EVENT_QUEUE_SIZE (CONFIG_ESP_SYSTEM_EVENT_QUEUE_SIZE)
CONFIG_SYSTEM_EVENT_TASK_STACK_SIZE (CONFIG_ESP_SYSTEM_EVENT_TASK_STACK_SIZE)
CONFIG_TASK_WDT (CONFIG_ESP_TASK_WDT)
CONFIG_TASK_WDT_CHECK_IDLE_TASK_CPU0 (CONFIG_ESP_TASK_WDT_CHECK_IDLE_TASK_CPU0)
CONFIG_TASK_WDT_CHECK_IDLE_TASK_CPU1 (CONFIG_ESP_TASK_WDT_CHECK_IDLE_TASK_CPU1)
CONFIG_TASK_WDT_PANIC (CONFIG_ESP_TASK_WDT_PANIC)
CONFIG_TASK_WDT_TIMEOUT_S (CONFIG_ESP_TASK_WDT_TIMEOUT_S)
CONFIG_TCPIP_RECVMBOX_SIZE (CONFIG_LWIP_TCPIP_RECVMBOX_SIZE)
- CONFIG_TCPIP_TASK_AFFINITY (CONFIG_LWIP_TCPIP_TASK_AFFINITY)
CONFIG_TCPIP_TASK_AFFINITY_NO_AFFINITY
CONFIG_TCPIP_TASK_AFFINITY_CPU0
CONFIG_TCPIP_TASK_AFFINITY_CPU1
CONFIG_TCPIP_TASK_STACK_SIZE (CONFIG_LWIP_TCPIP_TASK_STACK_SIZE)
CONFIG_TCP_MAXRTX (CONFIG_LWIP_TCP_MAXRTX)
CONFIG_TCP_MSL (CONFIG_LWIP_TCP_MSL)
CONFIG_TCP_MSS (CONFIG_LWIP_TCP_MSS)
- CONFIG_TCP_OVERSIZE (CONFIG_LWIP_TCP_OVERSIZE)
CONFIG_TCP_OVERSIZE_MSS
CONFIG_TCP_OVERSIZE_QUARTER_MSS
CONFIG_TCP_OVERSIZE_DISABLE
CONFIG_TCP_QUEUE_OOSEQ (CONFIG_LWIP_TCP_QUEUE_OOSEQ)
CONFIG_TCP_RECVMBOX_SIZE (CONFIG_LWIP_TCP_RECVMBOX_SIZE)
CONFIG_TCP_SND_BUF_DEFAULT (CONFIG_LWIP_TCP_SND_BUF_DEFAULT)
CONFIG_TCP_SYNMAXRTX (CONFIG_LWIP_TCP_SYNMAXRTX)
CONFIG_TCP_WND_DEFAULT (CONFIG_LWIP_TCP_WND_DEFAULT)
CONFIG_TIMER_QUEUE_LENGTH (CONFIG_FREERTOS_TIMER_QUEUE_LENGTH)
CONFIG_TIMER_TASK_PRIORITY (CONFIG_FREERTOS_TIMER_TASK_PRIORITY)
CONFIG_TIMER_TASK_STACK_DEPTH (CONFIG_FREERTOS_TIMER_TASK_STACK_DEPTH)
CONFIG_TIMER_TASK_STACK_SIZE (CONFIG_ESP_TIMER_TASK_STACK_SIZE)
CONFIG_TOOLPREFIX (CONFIG_SDK_TOOLPREFIX)
CONFIG_UDP_RECVMBOX_SIZE (CONFIG_LWIP_UDP_RECVMBOX_SIZE)
CONFIG_USE_ONLY_LWIP_SELECT (CONFIG_LWIP_USE_ONLY_LWIP_SELECT)
CONFIG_WARN_WRITE_STRINGS (CONFIG_COMPILER_WARN_WRITE_STRINGS)
Customisations¶
Because IDF builds by default with Warning On Undefined Variables, when the Kconfig tool generates Makefiles (the auto.conf file) its behaviour has been customised. In normal Kconfig, a variable which is set to “no” is undefined. In IDF’s version of Kconfig, this variable is defined in the Makefile but has an empty value.
(Note that ifdef and ifndef can still be used in Makefiles, because they test if a variable is defined and has a non-empty value.)
When generating header files for C & C++, the behaviour is not customised - so #ifdef can be used to test if a boolean config item is set or not.