Documentation for release v4.1 is available at https://docs.espressif.com/projects/esp-idf/en/v4.1/

ESP-IDF v4.1 is a minor update for ESP-IDF v4.0. ESP-IDF v4.1 will be supported until February 2023 in accordance with the ESP-IDF Support Policy.

Note: This is the first ESP-IDF release since the Support Policy was updated to change all ESP-IDF stable release support periods to 30 months. Previously this support period only applied to designated "Long Term Support" releases.

This is the list of changes since release v4.0:

Major New Features

Wi-Fi: Added support for Protected Management Frames (PMF)
Wi-Fi: Added SAE authentication support for WPA3 Personal
New Python-based menuconfig tool
Networking: Added new esp_netif API to manage network interfaces, replaces tcpip_adapter which is now deprecated.
Classic Bluetooth: Added support for Hands Free Profile (HFP) Audio Gateway (AG)
DTLS support in libcoap using mbedTLS (#3977)
Secure Boot V2 support (RSA based) added for ESP32 V3
Preview support for ESP32-S2 Beta SoC. This support will be replaced with ESP32-S2 SoC support in ESP-IDF v4.2. ESP32-S2 Beta firmware is not compatible with the ESP32-S2 production SoC, and not all features are supported.

Major Bug Fixes

Security fix: Fixed AP switch to adjacent channel without disconnect (-12638)
Updated toolchain fixes for PSRAM issue in ESP32 revisions prior to V3 (note: there is a known issue with this fix, see below.)

Breaking Changes

As part of the fix for -12638, the event WIFI_EVENT_STA_AUTHMODE_CHANGE has been removed. STA will now disassociate (with reason WIFI_REASON_AUTH_CHANGED) and reassociate in this case.

Known Issues

The esp-2020r2 toolchain has been added in this release which includes some fixes for C++ exceptions, a fix for -O2 optimization of volatile word accesses, and an improved PSRAM fix. Extended stress testing of Wi-Fi & BT coexistence with heavy PSRAM use show there is a difficult to reproduce issue with the updated PSRAM fix. It is possible to roll back to the esp-2020r1 toolchain release by running git revert --no-edit 298f23c9 in the ESP-IDF directory, then re-run the install.sh/install.bat/install.ps1 and . export.sh/export.bat/export.ps1 steps as described in the Get Started guide. This issue will be fixed in the v4.1.1 release.
A new macro to call a function with a user-allocated stack has been added but is non-functional
Using ADC in DMA mode does not work correctly
Can not correctly config IPv6 segmentation and reassembly from menuconfig
Nimble doesn't support non-resolvable private address
Watchdog timeout when using an RSA 4096-bit key to connect to WPA2-Enterprise (EAP-TLS) AP.
CAN driver doesn't work correctly if assertions are disabled in menuconfig

Bluetooth

Controller

Added API to query the number of available buffers for the current connection
Improved handling of calloc() failure
Fixed HCI timeout issues when using multiple cores and sleep is enabled
Fixed BLE crash issue triggered by BLE event interrupt missed
Fixed bugs related to role switch
Fall back to main XTAL as Bluetooth sleep clock source if the External 32kHz crystal is configured but not detected
Fixed a division by zero error in BT sleep clock cycle calculation
Fixed software assertion of invalid state when using HCI_Create_Connection_Cancel command
Fixed LMP timeout issue when handling LMP_sniff_req
Fixed the issue of repeatedly sending LMP_features_req_ext

Bluedroid

Fixed bug with fixed_queue semaphore pointer dereference
Fixed potential memcpy buffer overflow problem
Fixed wrong complete Identity Address (Public Address) of the Privacy-enabled Bonded Device got after bonding
Fixed the issue with pointer type conversion in gattc
Added missing GATT descriptors 0x2909 (Number of Digitals) through 0x290E (Time Trigger Setting) (#4082, #4470)
Fixed some spurious uninitialized variable warnings when optimization level set to Performance

NimBLE

Updated to 1.2.0 upstream NimBLE release, plus some subsequent upstream bugfixes
Added config option to enable host flow control
Added host based privacy (RPA) feature support
NimBLE stack buffers are now allocated dynamically instead of .bss. Added a config option to choose the allocation
Added new project configuration options for host task stack size
Added system level mbuf block count (MSYS_1) option in project configuration
Fixed check for static random address in ble_hs_id_set_rnd()
Increased maximum concurrent connections to 9 (controller supported)
Reduced the size of the compiled binary (espressif/esp-nimble#6)
Added upstream NULL pointer check (apache/mynewt-nimble#701)
Fixed pairing procedure abort on unexpected pairing request (apache/mynewt-nimble#710)
Fixed connection flags after pairing (apache/mynewt-nimble#730)
Removed notification for update process timeout (Vol 6, Part B, section 5.2) (apache/mynewt-nimble#782)
Fixed CCCD behavior in case of an overflow and while storing for bonded devices (apache/mynewt-nimble#790, apache/mynewt-nimble#804)

Classic Bluetooth

GAP: Added new esp_bt_gap_read_remote_name() function to get remote device's Bluetooth name at any time
GAP: Fixed error on EIR type in Config EIR event
HFP: Added Audio Gateway (AG) support
HFP: Added AT+NREC=0 command for disabling AG echo cancellation (#3665)
HFP: Fixed crash on incoming audio
HFP: Fixed connection fail and crash when receiving unknown AT command
HFP: Fixed AG audio crash (change the return position)
A2DP: Fixed assertion for de-initializing A2DP while audio streaming is ongoing
AVRC: Fixed AVRC metadata length error

Bluetooth Low Energy

Fixed BLE throughput wasting memory
Fixed the BLE throughput client crash when enable the CONFIG_GATTC_WRITE_THROUTHPUT option
Fixed client no BLE_AUTH_CMPL_EVT when client proactively initiate an encryption request after device restart
Fixed notify malloc failed when testing multi-connection notify performance
Fixed btc disable crash sometimes
Fixed don't dequeue the command queue after process the read_by_type_req
Add BLE API to set channel classification
Added support to enable Peripheral Preferred Parameters in GAP service
Fixed data loss and send same pkt twice sometimes
Fixed adv data error in air sometimes
Fixed adv start/stop crash sometimes
Fixed the wrong mask value according to HID protocol
Fixed GATTC trigger open event multiple times

Blufi

Fixed the wrong type from BLUFI_TYPE_DATA_SUBTYPE_SOFTAP_MAX_CONN_NUM to BLUFI_TYPE_DATA_SUBTYPE_SOFTAP_CHANNEL
Fixed blufi prepare write buf len invalid
Reply with an error response when the format of the received data packet is wrong
Check if BLE is connected before sending a message via BLE

ESP-BLE-Mesh

Miscellaneous modifications for Provisioner
- Support Provisioner persistent functionality
- Add a function to set Provisioner static oob value
- Add a function to set Provisioner unicast address
- Add a function to provision devices with fixed address
- Add a function to store node composition data
- Add a function to get node with device uuid
- Add a function to get node with unicast address
- Add a function to delete node with device uuid
- Add a function to delete node with unicast address
- Add a function for Provisioner to update local AppKey
- Add a function for Provisioner to update local NetKey
- Fix Provisioner entering IV Update procedure
- Fix Provisioner failed to publish messages
- Provisioner ignores msg from removed node
- Fixed Provisioner provisioning deadlock
- Checks if the AppKey exists before deleting it
- Updated next allocated address when node info is added
Synchronized a few Zephyr BLE Mesh updates
Support using a specific partition for BLE Mesh
Add a function to de-initialize BLE Mesh stack
Fixed use-after-free issue when de-initialize mesh
Fixed not free beacon timer when de-initialize mesh
Fixed de-initialize error when using NimBLE host
Supports using SPIRAM for BLE Mesh dynamic memory, queue, etc.
Fixed compile error when using performance optimization level
Fixed compile error when including from C++ files
Made RSSI value available to mesh applications
Fixed reset transport info when node is removed
Now allows sending maximum 377 octet payload
Now uses lock for mesh timer operations
Fix an issue which may cause client failing to send msg
Added check of the result of creating mesh timer
NULL can be used if client message has no parameters
Unified client application and lower transport layer timeout
Removed timeout for client message to non-unicast address
Fixed timer start when sending client message
Fixed client local parameters not initialized
Calculates incomplete message timeout based on message info
Added check of buf->ref before decrementing buffer ref count
Sensor models related miscellaneous fixes
Update the ESP BLE Mesh examples hierarchy
Added BLE Mesh vendor models examples
Added BLE Mesh sensor models examples
Added BLE Mesh whitelist test functions
Added option to send normal BLE advertising packets while connected to mesh
Changed to continue node info restore even if failure happens
Added check if assigned node address is duplicated
Removed BLE_MESH_MAX_STORED_NODES option
Associates replay protection list size with nodes count
Fixed time scene wrong spelled macro name
Add length check for some mesh operations
Fix not erasing mesh node information completely
Added a option to fix mesh node nvs information restore
Now initializes mesh node device name during proxy server init
Fix using old menuconfig options for mesh duplicate scan

Wi-Fi Coexistence

Fixed A2DP disconnect when Wi-Fi switches channels
Fixed A2DP stuck after creating another connection
Improve Wi-Fi TX & RX performance
Fixed wakeup delay when DFS is enabled
New API esp_coex_ble_conn_dynamic_prio_enable() allows configuring BLE/W-Fi relative priority in coexistence
Optimize WiFi/BT coexist sleep
Adjust coexist scheme when BT is in connected status

Wi-Fi

Added PMK caching feature for WPA2 Enterprise stations
Added support for Protected Management Frames (PMF)
Added SAE authentication support for WPA3 Personal
Fixed AP switch to adjacent channel without disconnect (-12638)
Wi-Fi now uses new esp_event library added in ESP-IDF v4.0
Fixed wpa_supplicant EAP re-authentication issue
Fixed wpa_supplicant assoc_ie_len setting based on generated RSN/WPA IE
Fixed EAPOL key used during reauthentication
Fixed memory leak on Wi-Fi stop
Added wpa_supplicant parsing support for WEP40 key
Fixed esp_wifi_set_max_tx_power description
Added new API esp_wifi_ap_get_sta_aid
Disabled wpa_supplicant TLS 1.2 support by default due to issues with some Enterprise Authentication Servers. This option can be enabled in menuconfig.
Fixed wpa_supplicant memory leaks and invalid memory access
Added check for Wi-Fi stop when calling esp_wifi_deinit
Now places the Vendor Specific element at the end according to the protocol
Fixed crash during WEP shared auth
Fixed WiFi buffer reload that WiFi receiving no longer works because internal buffer reloading fails
Fixed WiFi receiving that WiFi receiving no longer works because it writes the MAC registers when WiFi/BT common clock is disabled
Fixed WiFi performance, including AMPDU parameter negotiations, WiFi TX optimization etc
Fixed AMSDU decrypt that ESP32 can't decrypt the AMSDU if it's encrypted
Reduced Wi-Fi compiled binary size
Added TX packet length checking, Wi-Fi driver will drop a packet which is too long
Improved RSSI scan accuracy
Now returns an error if the setting AP's channel is out of range
Fixed sniffer during WiFi mode switching
Reduced Wi-Fi compiled binary size
Throughput improvements
Fixed Wi-Fi receive failure due to internal buffer reload failure
Fixed some Wi-Fi timer issues
Fix crash caused by too big of association request RSN information
Fixed setting channel when Wi-Fi is in NULL mode
Fixed the soft-AP incorrectly updates the second channel
Fixed AP switch to adjacent channel without disconnect
Added soft-AP example channel configuration
Fixed beacon timeout and station fails to connect to AP sometimes when WiFi and Bluetooth run together
Fixed the station can't get the IP address from China Mobile router
Fixed a timeout issue in the EAPOL four-way handshake
Added softap example channel configuration
Placed the Vendor Specific element at the end according to Wi-Fi spec
Fixed the bug for softAP update second channel wrong
Fixed internal scan data struct definition, changed wifi_scan_time_t from union to struct
Fixed country code query when policy change from manual to auto

ESP-WIFI-MESH

Remove coexist warnings for mesh.

ESP-NOW

Fixed unicast packet TX failure
Fixed randomly crash (#4311)
Fixed modifying the channel info of peer node
Fixed the crash when modifying peer node between unencrypted and encrypted
Fixed the bug for fetch peer
Fixed the bug that the channel parameter doesn't work when adding peer node

Smartconfig

Airkiss: Fixed bug where connection would timeout but success was returned (#3362)
Fixed the bug that airkiss find hidden AP fail

Ethernet

Fixed Ethernet interrupt crash when cache is disabled. New flag ETH_MAC_FLAG_WORK_WITH_CACHE_DISABLE introduced to support Ethernet MAC continuing to operate while cache is disabled.
Ensure that eth_driver handle is allocated in internal RAM (#4635)
Ensure that calling esp_eth_stop() stops the EMAC hardware layer
Improved reliability of ethernet driver start/stop/uninstall/install

Peripheral Drivers

Most drivers have been refactored internally, however public behaviour of existing APIs should be the same as in ESP-IDF V4.0
Added option to place UART ISR in IRAM
Added new ESP Serial Slave Link library to communicate with serial slave devices via SDIO or similar interfaces
CAN: Fixed can_reconfigure_alerts() function taking semaphore in a critical section
CAN: Fixed possible logging in critical sections
CAN: Added bitfields to can_message_t as an alternate way to set CAN message flags.
I2S: Fixed compile error if FreeRTOS header not included before I2S header (#4251)
LEDC: Added missing ledc_set_pin() function declaration
MCPWM: Fixed off-by-one error when setting period
SDSPI & SDMMC: Fixed gpio_pin_bit_mask truncation to max GPIO value 31
PSRAM: Added support for 2T mode
UART: Added simplified API to set threshold values for RX FIFO full and TX FIFO empty
SPI: Fixed bug where spihost handle could be allocated in PSRAM
SPI_SLAVE: Fixed assertion failure when spi_slave_initialize failed with DMA channel equals zero (#2740)
TIMER_GROUP: Fixes the interrupt enable/disable of timer groups
SIGMA_DELTA: Fixed the cpp guard in the header file

Core System

Added config option to retry 32 kHz external crystal calibration
Fixed DPORT ECO workaround register operation to improve workaround reliability. (Details of workaround in ECO document item 3.10 "When each CPU reads certain different address spaces simultaneously, a read error can occur")
Added likely & unlikely macros to help compiler produce optimized instruction sequences
Reorder some startup code to reduce amount of ESP_EARLY_LOGx logging in the app
bootloader_random: Added protected for shared CLK_EN & RST_EN registers when calling bootloader_random_enable()/_disable() in the app
esp_attr: Fixed multiple definition linker errors when using section attributes in C++ builds (#4021 )
esp_event: Fix a possible null pointer dereference (#4373)
esp_timer: Add parameter NULL checks to public API Return ESP_ERR_INVALID_ARG if the handle is NULL, instead of crashing.
heap: Added dedicated "aligned alloc" and "aligned free" functions functions (some restrictions apply, see linked documentation).
heap: Added new heap_caps_get_allocated_size() function
heap: Ensured malloc(0) will always return NULL
ipc: IPC now runs at priority of the caller's task, preventing priority inversion issue where one core commandeers the other core
log: Added option to log system time rather than RTOS time (#3958)
mac: Calling esp_base_mac_addr_set() now fails if MAC is not a unicast MAC (#4263)
pthread: Fixed pthread_once() possible race condition (#4561)
single core: Don't compile in unnecessary ipc code in single core configurations
startup: Clear RF PHY peripheral status during early startup
time: Added optional support for 64-bit time_t, depends on toolchain support which is not part of the default toolchain yet, this is planned for ESP-IDF v5.0.
toolchain: add new compiler optimization levels for "Performance" (-O2) and "None" (-O0)
heap: Only fill new heaps with FREE_FILL_PATTERN on init if Comprehensive poisoning is enabled, allowing faster boot in other situations (especially when PSRAM is used)

Debugging

core dump: Default Core Dump data format is now ELF (configurable)
core dump: Disable core dump to flash if stack in PSRAM option is enabled
panic handler: Moved some panic handler code into flash to reduce IRAM usage, cache will be re-enabled in panic handler if necessary
panic handler: Fixed printing of ELF file if cache is disabled

FreeRTOS

Reduced interrupt cycle overhead by using window overflow and underflow exceptions to speed up Xtensa register spills to the stack
Added support for including FreeRTOS headers using the traditional header paths, instead of requiring freertos/ prefix

newlib libc

Fixed linking of newlib nano from ROM only if PSRAM cache workaround is disabled

LWIP

Added option to automatically resolve mDNS queries when looking up .local addresses
Added IPV6 stateless address autoconfiguration support
Added config option for SO_LINGER
Cleaned up the TCP/IP stack port layer
Fixed crash when a netconn is marked as closed
Fix select_waiting() assert caused by UDP socket closing
Fix the crash caused by socket lock not initialized
Fixed issue with IPV6 TCP sending OK when STA disconnects
MLD6: Fixed error when attempting to join a non-multicast IPV6 address
Now includes hostname in DHCP discover packet, if set
PPPoS: Fixed power_down DCE immediately after getting IP
PPPoS: Allow esp_netif_ppp_set_auth set auth_type with NETIF_PPP_AUTHTYPE_NONE (#4639)
PPP client: Prevent rhostname array overflow (espressif/esp-lwip#14)
sntp: Added API to set the SNTP update interval (#4437)
Fixed assertion failure if killing a TCP connection not marked for closing yet
Fixed assertion failure if UDP socket is closed during select
Fixed failure to set DHCP timeout during system initialization

mDNS

Added configuration values for mDNS task priority, affinity, internal service timeouts
Fixed missing "bye" packet if services removed with mdns_service_remove_all() or mdns_free() (#3660)

Provisioning

NimBLE: Fix bug in protocomm_nimble chararcteristic access callback
Unified Provisioning: Fixed BLE characteristics read response issue when read response length is a multiple of () length
Wifi_provisioning_softap: Allow applications to start webserver externally
Wifi_prov_manager: Fix to ensure that provisioning status is reliably conveyed to remote host
Wifi_prov_manager: Fix to ensure Wi-Fi events still received after Connection errors
BLE: Change service_uuid to non-standard 128-bit UUID

OTA

Fixed bug where erase size could be one sector too long (#4953)
esp_https_ota: Added error checking functionalities. A few additional error checking mechanisms have been added which returns the control in case an invalid header is received, and a wrapper to the esp_http_client_is_complete_data_received() function of esp_http_client has been added.
esp_https_ota: Fixed OTA when using a server with chunked HTTP encoding
esp_https_ota: Added errno check for network disconnection when performing OTA

HTTP Client

Added esp_http_client_set_authtype() function (#4444)
Fixed HTTP client issue regarding message_complete callback invocation (fixes some issues with OTA failing with unexpected errors if the connection closes early)
Fixed memory leak in esp_http_client_set_username/password (#4444)

mbedTLS

Added new fast Montgomery exponentiation implementation for RSA accelerator. Significantly improves ESP32 RSA performance (especially public key operations)
Don't allow disabling ECDSA support in mbedTLS config if app image signature checking is enabled
Fixed incorrect compilation of MPI accelerator functions when hardware support is disabled (#5321)

ULP

Added some missing ULP macro functionality: stage counters, branch on stage counter, I2C operations. (#3580)
Added ULP macro MOVE <label> construct which helps when writing larger programs. (#3580)
Added a union member to allow getting the encoded ULP instruction from a macro result (#3759)

Bootloader

Added option to skip image validation when waking from deep sleep (incompatible with Secure Boot) (#3304)
Restructured bootloader initialization, moving target-specific initialization into separate source files
Fixed bug where bootloader header variable could be linked to an unaligned address, causing boot failure

ESP-TLS

Added support for WolfSSL backend (see https://github.com/espressif/esp-wolfssl)
Added timeout support for blocking connections

TCP Transport

Added API to use password protected client keys
Added functionality to use ALPN with SSL

Websocket

Added User-Agent and additional headers to websocket client (#4345)
Fixed opcodes when performing a fragmented send (#4974)

ESP-MQTT

Added functionality to use ALPN with SSL
Added option to configure MQTT task priority (#4947)
Added support for PSK authentication (espressif/esp-mqtt#95)
Added functionality to use certificates in DER format
Added support for password protected client-key

Storage

FATFS: handle the internal FR_INT_ERR error as "filesystem corrupted"
NVS: Add support to expose a NVS entry via a C++ smart pointer handle
NVS: Fixed iterator skipping version 1 blobs (#4954)
SPIFFS: Fixed bugs when CONFIG_SPIFFS_USE_MTIME is not defined
SPIFFS: Now follows symlinks in spiffsgen (#3778)
spi_flash: Fixed regression in task delays during long erase operations, preventing starvation of other tasks
spi_flash: Fixed possible task watchdog timeout by adding vTaskDelay during long erase
spi_flash: Fixed over-allocation and possible OOM crash when reading from SPI Flash to PSRAM (#4769)
spi_flash: Fixed the inconsistency in clock between SPI0 and SPI1. (#5099)

VFS

VFS: Check in select() if the UART driver is installed or not

Modbus

Added support for Modbus ASCII master mode
Fixed issue re-initializing Modbus controller after call to mbc_master_destroy()

External Libraries

coap: Improved support for different mbedTLS configurations (#3961, #3971, #3977)
jsmn: Added project configuration options for library (#4416)
mbedTLS: Updated to v2.16.5
tinycbor: Added new tinycbor component and example

Tools

c++: Allow enabling RTTI
idf_monitor: Work around a Windows driver bug when using a USB-CDC device
idf_monitor: fix the bug that idf_monitor not blocked when no log printed (#3884)
idf_monitor: Fixed flashing encrypted binaries from IDF Monitor
idf_size: Added support to write size data to a JSON file
idf_size: Significantly improved performance (#4518)
openocd: Documented support for ARM architecture
parttool: Fixed crash when retrieving partition info (#5271)

Build System

Added PowerShell versions of "install.bat" and "export.bat" for Windows PowerShell users
Added idf.py --cache option and support for setting config variable IDF_ENABLE_CCACHE to permanently enable CCache
Added minor fixes for convert_to_cmake.py
Added new idf.py --version command
Allow idf.py and CMake build system to work on FreeBSD (not officially supported) (#2029)
Added new idf.py --monitor-baud option (can also set default with IDF_MONITOR_BAUD environment variable)
Fix IDF_PATH case mismatches on case insensitive filesystems
Fixed execution order for dependent tasks
Updated kconfiglib to the upstream version, switch to a Python-based menuconfig tool
ldgen linker script mapping rules order is now deterministic
Fixed generation of hex config values for Make & CMake (espressif/vscode-esp-idf-extension#83)
Updated MSYS2 legacy build environment to use Python 3 (Python2 packages have been removed from MSYS2)

Examples

http_request: Fixed some non-compliant parts of the HTTP request, made example configurable
Improved the example behaviour when esp_restart() is called and Wi-Fi is initialized
ping: Added new example
restful server: Added NetBIOS support for discovery
tcp_server: Fixed unnecessary reopening of listening socket
efuse: Added example demonstrating efuse API for writing efuses
ble throughput: Fixed intermittent crash when running the BLE throughput client
ble hid device: Fixed the wrong mask value based on the HID protocol
ble hid device: Fixed issue with security info restore when a paired BLE HID device disconnects and then reconnects after a BT Classic HID device has connected
BLE mesh: Update mesh console example
BLE mesh: Added BLE mesh vendor models examples
BLE mesh: Added BLE mesh sensor model examples
blufi: Changed the Wi-Fi storage mode to default WIFI_STORAGE_FLASH
bluetooth: Added HFP Audio Gateway example
ota: Fixed bug with failing OTA if the connection closed prematurely
softap example: Added channel configuration

Documentation

Translated more ESP-IDF Programming Guide pages into Chinese
Added basic C++ style guide
Encourage Python 3 rather than Python 2 for new users
Added Getting Started Guide for Ethernet Kit V1.1
Added some definitions removed during driver refactoring back to API reference
Included feedback link in footer of all documentation pages
Removed duplicate commands and invalid serial port information in description of examples
Corrected description of ULP instructions REG_WR and REG_RD
Added caveats about using JTAG debugging with hardware security features

Obtaining v4.1

For full installation instructions, see the ESP-IDF Programming Guide.

The source files attached to this release will not work due to our use of git submodules. Use one of the following methods instead:

Using git

To get this release, use the following commands:

git clone -b v4.1 --recursive https://github.com/espressif/esp-idf.git esp-idf-v4.1
cd esp-idf-v4.1/

This is the recommended way of obtaining v4.1 of ESP-IDF.

Download an archive with submodules included

Attached to this release is an esp-idf-v4.1.zip archive. It includes .git directory and all the submodules, so can be used out of the box. This archive is provided for users who have connectivity issues preventing them from cloning from GitHub.

This archive can also be downloaded from Espressif's download server:
https://dl.espressif.com/dl/esp-idf/releases/esp-idf-v4.1.zip

espressif/esp-idf v4.1 ESP-IDF Release v4.1 on GitHub