This is an experimental port of MicroPython for the WiFi modules based on Espressif ESP8266 chip.
WARNING: The port is experimental and many APIs are subject to change.
Supported features include:
Documentation is available at http://docs.micropython.org/en/latest/esp8266/quickref.html.
You need the esp-open-sdk toolchain (which provides both the compiler and libraries), which you can obtain using one of the following two options:
Use a Docker image with a pre-built toolchain (recommended). To use this, install Docker, then prepend docker run --rm -v $HOME:$HOME -u $UID -w $PWD larsks/esp-open-sdk to the start of the mpy-cross and firmware make commands below. This will run the commands using the toolchain inside the container but using the files on your local filesystem.
or, install the esp-open-sdk directly on your PC, which can be found at https://github.com/pfalcon/esp-open-sdk. Clone this repository and run make in its directory to build and install the SDK locally. Make sure to add toolchain bin directory to your PATH. Read esp-open-sdk's README for additional important information on toolchain setup. If you use this approach, then the command below will work exactly.
Add the external dependencies to the MicroPython repository checkout:
$ make -C ports/esp8266 submodules
See the README in the repository root for more information about external dependencies.
The MicroPython cross-compiler must be built to pre-compile some of the built-in scripts to bytecode. This can be done using:
$ make -C mpy-cross
(Prepend the Docker command if using Docker, see above)
Then, to build MicroPython for the ESP8266, just run:
$ cd ports/esp8266 $ make
(Prepend the Docker command if using Docker, see above)
This will produce binary images in the build-GENERIC/ subdirectory. If you install MicroPython to your module for the first time, or after installing any other firmware, you should erase flash completely:
$ esptool.py --port /dev/ttyXXX erase_flash
You can install esptool.py either from your system package manager or from PyPi.
Erasing the flash is also useful as a troubleshooting measure, if a module doesn't behave as expected.
To flash MicroPython image to your ESP8266, use:
$ make deploy
(This should not be run inside Docker as it will need access to the serial port.)
This will use the esptool.py script to download the images. You must have your ESP module in the bootloader mode, and connected to a serial port on your PC. The default serial port is /dev/ttyACM0, flash mode is qio and flash size is detect (auto-detect based on Flash ID).
To specify other values for esptool.py, use, e.g.:
$ make PORT=/dev/ttyUSB0 FLASH_MODE=qio FLASH_SIZE=32m deploy
(note that flash size is in megabits)
If you want to flash manually using esptool.py directly, the image produced is build-GENERIC/firmware-combined.bin, to be flashed at 0x00000.
The default board definition is the directory boards/GENERIC. For a custom configuration you can define your own board in the directory boards/.
The BOARD variable can be set on the make command line, for example:
$ make BOARD=GENERIC_512K
512KB FlashROM version
The normal build described above requires modules with at least 1MB of FlashROM onboard. There's a special configuration for 512KB modules, which can be built with make BOARD=GENERIC_512K. This configuration is highly limited, lacks filesystem support, WebREPL, and has many other features disabled. It's mostly suitable for advanced users who are interested to fine-tune options to achieve a required setup. If you are an end user, please consider using a module with at least 1MB of FlashROM.
Be sure to change ESP8266's WiFi access point password ASAP, see below.
Serial prompt
You can access the REPL (Python prompt) over UART (the same as used for programming).
Run help() for some basic information.
WiFi
Initially, the device configures itself as a WiFi access point (AP).
help() gives information how.WebREPL
Python prompt over WiFi, connecting through a browser.
upip
The ESP8266 port comes with builtin upip package manager, which can be used to install additional modules (see the main README for more information):
>>> import upip
>>> upip.install("micropython-pystone_lowmem")
[...]
>>> import pystone_lowmem
>>> pystone_lowmem.main()
Downloading and installing packages may requite a lot of free memory, if you get an error, retry immediately after the hard reset.
More detailed documentation and instructions can be found at http://docs.micropython.org/en/latest/esp8266/ , which includes Quick Reference, Tutorial, General Information related to ESP8266 port, and to MicroPython in general.
While the port is in beta, it's known to be generally stable. If you experience strange bootloops, crashes, lockups, here's a list to check against:
Please consult dedicated ESP8266 forums/resources for hardware-related problems.
Additional information may be available by the documentation links above.