8b662ed3b3
* PoC cache configuration control Expaned boards.txt.py to allow new MMU options and create revised .ld's Updated eboot to pass 48K IRAM segments. Added Cache_Read_Enable intercept to modify call for 16K ICACHE Update platform.txt to pass new mmu options through to compiler and linker preprocessor. Added quick example: esp8266/MMU48K * Style corrections Added MMU_ qualifier to new defines. Moved changes into their own file. Don't know how to fix platformio issue. * Added detailed description for Cache_Read_Enable. Updated tools/sizes.py to report correct IRAM size and indicate ICACHE size. Merged in earlephilhower's work on unaligned exception. Refactored and added support for store operations and changed the name to be more closely aligned with its function. Improved crash reporting path. * Style and MMU_SEC_HEAP corrections. * Improved asm register usage. Added some inline functions to aid in byte and short access to iRAM. * only byte read has been tested Updated .ld file to work better with platform.io; however, I am still missing some steps, so platformio will still fail. * Interesting glitch in boards.txt after github merge. A new board in master was missing new additions added by boards.txt.py in the PR. Which the CI flags when it rebuilds boards.txt. * Support for 2nd Heap, excess IRAM, through umm_malloc. Adapted changes to umm_malloc, Esp.cpp, StackThunk.cpp, WiFiClientSecureBearSSL.cpp, and virtualmem.ino to irammem.ino from @earlephilhower PR #6994. Reworked umm_malloc to use context pointers instead of copy context. umm_malloc now supports allocations from IRAM. Added class HeapSelectIram, ... to aid in selecting alternate heaps, modeled after class InterruptLock. Restrict alloc request from ISRs to DRAM. Never ending improvements to debug printing. Sec Heap option now pulls in free IRAM left over in the 1st 32K block. Managed through umm_malloc with HeapSelectIram. Updated examples. * Post push CI cleanup. * Cleanup part II * Cleanup part III * Updates to support platformio, maybe. * Added exception C wrapper replacement. * CI Cleanup * CI Cleanup II Don't know what to do with platformio it doesn't like my .S file. ifdef out USE_ISR_SAFE_EXC_WRAPPER to block the new assemlby module from building on platformio only. * Changes to exc-c-wrapper-handler.S to assemble under platformio. * For platformio, Correction to toolchain-xtensa include path. @mcspr, Thankyou! * Temporarily added --print-memory-usage to ld parameters for cross-checking IRAM size. * undo change to platform.txt * correct merge conflict. take 1 * Fixed #if... for building umm_get_oom_count. It was not building when UMM_STATS_FULL was used. * Commented out XMC support. Compatibility issues with PoC when using 16K ICACHE. * Corrected size.py, DRAM bracketing changed to not include ICACHE with DRAM total. * Added additional _context for support of use of UMM_INLINE_METRICS. Corrected some UMM_POSION missed edits. * Changes to clear errors and warnings from toolchain 10.1 Several fixes and improvements to example MMU48K. With the improved optimization in toolchain 10.1 The example divide by 0 exception was failing with a HWDT event instead of its exception handler. The compiler saw the obscured divide by 0 and replaced it with a break point. * Isolated incompatable definitions related to _xtos_set_exception_handler. GDBSTUB definitions are different from the BootROM's. * Update tools/platformio-build.py Co-authored-by: Max Prokhorov <prokhorov.max@outlook.com> * Requested changes Changed mmu related usages of ETS_... defines to DBG_MMU_... Cleanup in example MMU48K.ino. Removed stale memory reference macro and mmu_status print statement. Cleanup printf '\n' to be '\r\n'. Improved issolation of development debug prints from the rest of the debug prints. * Corrected comment. And added missing include. * Improve comment. * style and comment correction * Added draft mmu.rst file and updated index. Updated example HeapMetric.ino to also illustrate use of IRAM Improved comments in exc-c-wrapper-handler.S. Added insurance IRQ disable. * Updated mmu.rst Improved function name uniqueness for is_iram, is_dram, and is_icache by adding prefix mmu_. Also, made them available outside of a debug build. Made pointer precision width more specific. Made some of the static inline functions in mmu_irm.h safe for ISRs by setting then for always inline. * Add a default MMU_IRAM_SIZE value for a new CI test to pass. Extended use 'umm_heap_context_t *_context' argument in ..._core functions and expanded its usage to reduce unnecessary repeated calls to umm_info(NULL, false), also removed recursion from umm_info(NULL, true). Fixed stack buffer length in umm_info_safe_printf_P and heap.cpp. Added example for creating an IRAM reserve section. Updated mmu.rst. Grammar and spelling corrections. * CI appeasement * CI appeasement with comment correction. * Ensure SYS always runs with DRAM Heap selected. * Add/move heap stack overflow/underflow check to Esp.cpp where the event was discarded. * Improved comment clarity of purpose for IramReserve.ino. Clean up MMU48K.ino * Added missing #include * Corrected usage of warning * CI appeasement and use #message not #pragma message * Updated git version of eboot.elf to match build version. Good test catch. * Remove conditional build option USE_ISR_SAFE_EXC_WRAPPER, always install. Use the replacement wrapper on non32xfer_exception_handler install. Added comments to code describing some exception handling issues. * Updated mmu.rst * Expanded and clarified comments. Limited access to some detailed typdefs/prototypes to .cpp modules, to avoid future build conflicts. Completed TODO for verifing that the "C" structure struct __exception_frame matches the ASM version. Fixed some typo's, code rot, and added some more cases in examaple irammem.ino. Refactored a little and reordered printing to ease comparison between methods. Corrected `#ifdef __cplusplus` coverage area. Cleaned up `extern "C" ...` usage. Fixes issues with including mmu_iram.h or esp8266_undocumented.h in .c files. * Style fixes and more cleanup * Style fix * Remove unnessasary IRAM_ATTR from install_non32xfer_exception_handler Some comment tuning. In the context of _xtos_set_exception_handler and the functions it registers, changed to type int for exception cause type. This is also the type used by gdbstub and some other Xtensa files I found.
Arduino core for ESP8266 WiFi chip
Quick links
Arduino on ESP8266
This project brings support for the ESP8266 chip to the Arduino environment. It lets you write sketches, using familiar Arduino functions and libraries, and run them directly on ESP8266, with no external microcontroller required.
ESP8266 Arduino core comes with libraries to communicate over WiFi using TCP and UDP, set up HTTP, mDNS, SSDP, and DNS servers, do OTA updates, use a file system in flash memory, and work with SD cards, servos, SPI and I2C peripherals.
Contents
- Installing options:
- Documentation
- Issues and support
- Contributing
- License and credits
Installing with Boards Manager
Starting with 1.6.4, Arduino allows installation of third-party platform packages using Boards Manager. We have packages available for Windows, Mac OS, and Linux (32 and 64 bit).
- Install the current upstream Arduino IDE at the 1.8.9 level or later. The current version is on the Arduino website.
- Start Arduino and open the Preferences window.
- Enter
https://arduino.esp8266.com/stable/package_esp8266com_index.jsoninto the File>Preferences>Additional Boards Manager URLs field of the Arduino IDE. You can add multiple URLs, separating them with commas. - Open Boards Manager from Tools > Board menu and install esp8266 platform (and don't forget to select your ESP8266 board from Tools > Board menu after installation).
Latest release 
Boards manager link: https://arduino.esp8266.com/stable/package_esp8266com_index.json
Documentation: https://arduino-esp8266.readthedocs.io/en/2.7.4_a/
Using git version
Also known as latest git or master branch.
- Install the current upstream Arduino IDE at the 1.8 level or later. The current version is on the Arduino website.
- Follow the instructions in the documentation.
Using PlatformIO
PlatformIO is an open source ecosystem for IoT development with a cross-platform build system, a library manager, and full support for Espressif (ESP8266) development. It works on the following popular host operating systems: macOS, Windows, Linux 32/64, and Linux ARM (like Raspberry Pi, BeagleBone, CubieBoard).
- What is PlatformIO?
- PlatformIO IDE
- PlatformIO Core (command line tool)
- Advanced usage - custom settings, uploading to SPIFFS, Over-the-Air (OTA), staging version
- Integration with Cloud and Standalone IDEs - Cloud9, Codeanywhere, Eclipse Che (Codenvy), Atom, CLion, Eclipse, Emacs, NetBeans, Qt Creator, Sublime Text, VIM, Visual Studio, and VSCode
- Project Examples
Building with make
makeEspArduino is a generic makefile for any ESP8266 Arduino project. Using make instead of the Arduino IDE makes it easier to do automated and production builds.
Documentation
Documentation for latest development version: https://arduino-esp8266.readthedocs.io/en/latest/
Issues and support
ESP8266 Community Forum is a well-established community for questions and answers about Arduino for ESP8266. Stackoverflow is also an alternative. If you need help, have a "How do I..." type question, have a problem with a 3rd party library not hosted in this repo, or just want to discuss how to approach a problem, please ask there.
If you find the forum useful, please consider supporting it with a donation.
If you encounter an issue which you think is a bug in the ESP8266 Arduino Core or the associated libraries, or if you want to propose an enhancement, you are welcome to submit it here on Github: https://github.com/esp8266/Arduino/issues.
Please provide as much context as possible, as well as the information requested in the issue template:
- ESP8266 Arduino core version which you are using (you can check it in Boards Manager)
- your sketch code; please wrap it into a code block, see Github markdown manual
- when encountering an issue that happens at run time, attach the serial output. Wrap it into a code block, just like the code.
- for issues that happen at compile time, enable verbose compiler output in the IDE preferences, and attach that output (also inside a code block)
- ESP8266 development board model
- IDE settings (board choice, flash size)
- etc
Contributing
For minor fixes of code and documentation, please go ahead and submit a pull request. A gentle introduction to the process can be found here.
Check out the list of issues that are easy to fix — easy issues pending. Working on them is a great way to move the project forward.
Larger changes (rewriting parts of existing code from scratch, adding new functions to the core, adding new libraries) should generally be discussed by opening an issue first. PRs with such changes require testing and approval.
Feature branches with lots of small commits (especially titled "oops", "fix typo", "forgot to add file", etc.) should be squashed before opening a pull request. At the same time, please refrain from putting multiple unrelated changes into a single pull request.
License and credits
Arduino IDE is developed and maintained by the Arduino team. The IDE is licensed under GPL.
ESP8266 core includes an xtensa gcc toolchain, which is also under GPL.
Esptool.py was initially created by Fredrik Ahlberg (@themadinventor, @kongo), and is currently maintained by Angus Gratton (@projectgus) under GPL 2.0 license.
Espressif's NONOS SDK included in this build is under Espressif MIT License.
ESP8266 core files are licensed under LGPL.
SPI Flash File System (SPIFFS) written by Peter Andersson is used in this project. It is distributed under the MIT license.
umm_malloc memory management library written by Ralph Hempel is used in this project. It is distributed under the MIT license.
SoftwareSerial library and examples written by Peter Lerup. Distributed under LGPL 2.1.
BearSSL library written by Thomas Pornin, built from https://github.com/earlephilhower/bearssl-esp8266, is used in this project. It is distributed under the MIT License.
LittleFS library written by ARM Limited and released under the BSD 3-clause license.
uzlib library written and (c) 2014-2018 Paul Sokolovsky, licensed under the ZLib license (https://www.zlib.net/zlib_license.html). uzlib is based on: tinf library by Joergen Ibsen (Deflate decompression); Deflate Static Huffman tree routines by Simon Tatham; LZ77 compressor by Paul Sokolovsky; with library integrated and maintained by Paul Sokolovsky.
Other useful links
Serial Monitor Arduino IDE plugin Original discussion here, quick download there.