Documentation

• Expand the hardware debugging limitations section (#8879)

CI

• Emulation on host: fix UDP seek&peek (#8827)

Release 3.1.1 Notes

Core

• Transparently manage recurrent scheduled functions in delay() (#8802)
• Fix C builds when including coredecls.h and / or core_esp8266_features.h (#8795)
• Typo in EAP patch (#8797)
• Fix clang warnings related to constexpr usage (#8796)
• Fix printf format in Updater debug messages (#8791)

Examples

• Remove 400b stack allocation from Advanced Web example (#8793)

Build system

• Also apply #8226 portable python fix to mkbuildopts script (#8804)
• Attempt to fix elf2bin.py not always working on Windows (#8799)

CI

• Document updating the GitHub deployment keys (#8790, #8792)

Release 3.1 Notes

Great additions

• NONOS SDK 3.0.5 (#8736, #8746, #8755, #8770)
• Support for global build defines and options for Arduino IDE (#8504)
• WPA2-Enterprise (#8529, #8566)
• (experimental) Flash-size agnostic builds (#6690)

Additions

• DHCP custom option(s) for DhcpServer (#8582)
• Updater lifetime callbacks (#8653)
• Add WiFiClient::abort() (#8738)

Notable changes

• hostByName timeout fixes (#8787)
• PHY status API for ethernet drivers (#8784)
• Update to EspSoftwareSerial 7.0.0 (#8781)
• Keep Servo in the same position after re-attaching (#8753)
• Fix WiFiClientSecure remoteIP(), remotePort(), localIP(), localPort() functions (#8693)
• mDNS - valid board for _adruino._tcp service (#8634)
• Allow longer delays for Ticker (#8625)
• ArduinoOTA and ESP8266HTTPUpdate no longer stop all WiFiClient/WiFiUDP (#8598)
• WiFiServer - rename available() to accept(), deprecate available() (#8419)
• Avoid out-of-bounds reads in String (#8463, #8597)
• Fix compilation issues and update toolchain (#8393, #8613)
• Update to SdFat 2.1.1 with UTF-8 support (#8355)
• lwIP v2.1.3 + various fixes (#8319, #8596)
• WiFiServer - 'rename' available() to accept() (#8419)
• WiFiServer - don't inherit from Server class (#8418)
• I2C clock phase correction in START condition (#8383)
• MMU functions strict aliasing fixes (#8290)
• Add FSTools with examples of how to convert between SPIFFS and LittleFS (#7696)
• Rename esp_yield() to esp_suspend(), update esp_yield() to also call esp_schedule() (#7148)

Breaking changes

None

Changes

SDK

• Added NONOS SDK 3.0.5 (#8736, #8770)
• Resolve flash address issues with SDK 3.0.x (#8755)
• Heap addendum to handle changes in NON-OS SDK 3.0.x (#8746)
• Fix missing NONOS SDK 2.2.x 19-03-13 (#7965, #8363)

Core

• Fix flashinit panic not printing (#8762)
• Fix Stream::parseFloat() (#8785)
• Added missing DRAM fallback to pvPortCallocIram, pvPortZallocIram, and (#8765)
• Fix pre-SDK Cache_Read_Enable for PUYA flash (#8658)
• OTA: Updater lifetime callbacks (#8653)
• Nice stack smashing postmortem message (#8670)
• Ensure xPortGetFreeHeapSize reports DRAM (#8680)
• SPI: writePattern() should not call setDataBits(0) (#8636)
• Correctly handle unaligned address in EspClass::flashWrite u8 overload (#8605)
• Add esp_is_8285(), check for ESP8285 at runtime (#8604)
• Allow to use temporary strings in configTime (#8606)
• Allow UART1 to be inverted (#8601)
• Avoid reading past end of non-zero terminated char arrays (#8597)
• Fix DTR offset value (#8586)
• WString: remove operator==(const __FlashStringHelper*) (#8569)
• Permit using the Updater _hash function, even if we don't have a signature appended to the image (#8507, #8545)
• Test: fixing itoa implementation and clean-up of tests and test Makefile (#8531)
• WString: unify numeric conversion and fix assignments (#8526)
• Fix OOM print handling of NULL file pointer (#8527)
• Heap panic / abort cleanup (#8465)
• Heap init code improvements and updates (#8458)
• Fix, calloc now fails on extra-large request. (#8482)
• Flash-size agnostic builds (#6690)
• WString: avoid writing to const storage (#8463)
• Fix Stream::read into buffer ignoring every second byte (#8452, #8453)
• Fix VM Address mask (#8440)
• Import getLocalTime() from esp32/Arduino (#8413)
• Sync umm_malloc style with upstream (#8426)
• StreamConstPtr: disallow passing a String temporary (#8410)
• Fix umm_blocks() (#8429)
• Missing includes in StreamString.h (#8367)
• Implement esp_yield() as a replacement for delay(0) (#7148)
• Update mmu_get... and mmu_set... (#8290)
• Reduce build size by implementing flash string overloads for String (#8106)

Libraries - FS

• Update to LittleFS 2.5.1 (#8543, #8786)
• Fix File::readString to work with binary data (#8742)
• Add FSTools with examples of how to convert between SPIFFS and LITTLEFS. (#7696)
• Correctly using fs:: namespace in SD & SDFS (#8493)
• Move ESP8266SDFat library to master, not branch (#8460)
• Fix info.usedBytes calculation giving weird result (#8445)
• LittleFS: add overrides for Stream::send (#8386)
• Update to SdFat 2.1.1 with UTF-8 support (#8355)
• Clean up SpeedTest output, avoid div-by-0 (#8340)

Libraries - Network

• hostByName timeout fixes (#8787)
• PHY status API for ethernet drivers (#8784)
• lwip2: cleanup logging and use newlib printf (#8769)
• Consistent netif->status_callback (#8676)
• Make WiFi/Ethernet interface compatible with Arduino Ethernet API (#8645)
• Fix WiFi/Ethernet hostname management (#8626)
• Add WiFiClient::abort() (#8738)
• Provide wl_tcp_state as tcp_state alias (#8609)
• Do not call tcp/udp ::stopAll() when it is not required to do so (#8598)
• Fix lwip2 ping (#8596)
• DHCP custom option(s) for DhcpServer (#8582)
• lwIP on ethernet: examples (#8395)
• Define lwIP's s32/u32 to int (#8560)
• Update RFC 5246 URL (#8564)
• lwIP: v2.1.3 + dhcp fixes (#8319)
• WiFiServer - 'rename' available() to accept() (#8419)
• WiFiServer - don't inherit from Server class (#8418)
• WiFi library ArduinoWiFiServer update (#8238)
• Place deprecated attribute in front of function (#8258)

Libraries - WiFi

• Allow passing beacon interval to SoftAP config (#8695)
• Optimize disconnect method in WiFiSTA class (#8760)
• Add eraseap option to WiFi disconnect method. (#8758)
• Allow to access bss_info after scan (#8683)
• Patch eap.o memory leak (#8566)
• Fix double-free when connecting to WPA2-Enterprise networks (#8529)
• Initialize SoftAP DhcpServer object on demand (#8546)
• Correctly access WIFI_EVENT_MODE_CHANGE event info (#8343)
• Return WL_WRONG_PASSWORD when calling begin() w/ invalid password (#8229)

Libraries - TLS/SSL

• Don't return true with WiFiClientSecureBearSSL::connected() when really disconnected (#8330)
• Only check the actual used length of the hash (#8709)
• Fix WiFiClientSecure remoteIP(), remotePort(), localIP(), localPort() functions (#8693)
• SSL examples updates (#8643)
• Update example certs (#8642)
• Update to latest BearSSL (#8600)
• Delete operator=(Self&) when copy constructor is deleted (#8535)
• Update sessions example to show speed difference (#8528)

Libraries - ESP8266WebServer

• Stop incorrectingly increase number of arguments when setting up arg("plain") (#8599)
• Use String when working with Basic authentication (#8548)
• Fix missing implementation of send stream by reference (#8533)
• Drop inactive connection when another is waiting to improve page load time (#8216)
• Optional ETag support, custom generator function (#8227)

Libraries - Wire

• Buffer length improvements (#8398)
• Allow to override buffer length (#8390)
• I2C clock phase correction in START condition (#8383)

Libraries - HTTPUpdate

• Allow passing custom HTTPClient (#8773)
• Correct class name in readme.rst (#8751)
• Add DEBUG payload output (#8745)
• Add setClientTimeout() (#8740)
• Fix missing include in OTA example (#8667)
• Catch a possible null-dereference (#8508)
• Allow manually setting MD5 checksum (#8204)

Libraries - HTTPClient

• Fix connection reuse for different URIs in ::begin (#8466)
• Prevent empty user-agent in header (#8411)
• Movable HTTPClient and fixing WiFiClient copy (#8237)
• Add writeToPrint (#8056)
• Pass authorization String by value (#8225)
• Add ::DELETE() (#8214)

Libraries - ArduinoOTA

• Fix compilation when no global MDNS instance is available (#8478)
• Add ::end() (#8379)

Libraries - mDNS

• Restart mDNS when network state changes (#8705)
• Also increase # of sends when a send fails (#8641)
• Report valid Board ID (#8634)
• Fix timeout type (#8394)
• Remove obsolete comments about legacy mDNS impl. (#8377)

Libraries - others

• Update to EspSoftwareSerial 7.0.0 (#8260, #8295, #8353, #8370, #8373, #8541, #8739, #8754, #8781)
• Remove temporary buffer in common ConfigFile example .ino (#8298)
• DNS Server: Add DNS forwarder to DNSServer (#7237)
• Netbios: Use current netif address in response (#8622)
• Servo: Keep Servo in the same position after re-attaching (#8753)
• HTTPUpdateServer Allow external POSTS (CORS) (#6824)
• Ticker: Allow longer delays and some internal updates (#8625)

Tools

• Stack decoder script (#8661)
• Do not show python traceback when esptool fails (#8603, #8608)
• Table output for segment size script (#8551, #8572, #8573)

Documentation

• Correction on Heap API available from ISR (#8708)
• We are no longer using Travis CI (#8706)
• Update WiFi scan docs (#8685)
• Fix Sphinx build warnings (#8686)
• Add missing license headers (#8630)
• Update FS documentation (#8619)
• Document side effects for wifi-off-at-boot (#8614)
• Correct "list" formatting (#8610)
• Update broken links (#8589)
• Add documentation entry about compiler warnings (#8492)
• Remove Python installation from OTA doc (#8417)
• comments on Arduino flush() method (#8318)

Boards

• Add Wemos ESP-WROOM-02 board (#8664)
• MOD-WIFI-ESP8266(-DEV) update (#8297)

Build system

• PIO: Fix CPPDEFINES loop (#8744)
• ldscripts: Fix typo in section list (#8726)
• Add debug support for build.opt (#8637)
• Rebuilt HAL w/latest toolchain and fixed configure (#8615)
• PIO: Move _GNU_SOURCE from CCFLAGS to CPPDEFINES (#8579)
• PIO: Improve support for hand-written asm source files (#8583)
• platform.txt: Override python3 anon pipe encoding to utf-8 for 'tools/sizes.py' (#8570)
• Add support for global build defines and options (#8504, #8565)
• Table output for segment size script (#8551)
• Properly quote paths for GCC warnings files (#8523)
• Fix minor typo in generated comment (#8503)
• Migrate from astyle to clang-format (#8464)
• Minor git install documentation fix (#8488)
• Remove obsolete PWMRANGE in keywords.txt (#8447)
• Correctly link with precompiled libraries (#8392)
• Remove warnings, errors during host tests in CI (#8358)
• Respect linking order of libraries for PlatformIO (#8263)

CI

• Remove paths / paths-ignore condition from CI (#8704)
• Rework CI workflows (#8688)
• emulation on host: fix incorrect lwIP DNS implementation (#8627)
• Github Actions updates and setup dependabot (#8624)
• Fix python warnings and update device tests runner (#8623)
• emulation on host: avoid closing STDIN (#8577)
• emulation on host: allow parallel compilation units (#8574)
• CI: update arduino IDE url (#8563)
• emulation on host: fix internal udp management (#8561)
• emulation on host: fix for latest changes in DNSServer (#8559)
• Correction to run_CI_locally.sh (#8552)
• ci: make sure to kill gpg related processes (#8549)
• Error even w/warnings disabled for no-return fcns (#8495)
• gitignore: Skip .git{,hub} files when packaging (#8743)
• emulation on host: minor updates (#8454)
• Emulation on host: updates (#8409)