96 lines
4.2 KiB
ReStructuredText
96 lines
4.2 KiB
ReStructuredText
|
Introduction to MicroPython on the ESP8266
|
||
|
|
==========================================
|
||
|
|
|
||
|
|
Using MicroPython is a great way to get the most of your ESP8266 board. And
|
||
|
|
vice versa, the ESP8266 chip is a great platform for using MicroPython. This
|
||
|
|
tutorial will guide you through setting up MicroPython, getting a prompt, using
|
||
|
|
WebREPL, connecting to the network and communicating with the Internet, using
|
||
|
|
the hardware peripherals, and controlling some external components.
|
||
|
|
|
||
|
|
Let's get started!
|
||
|
|
|
||
|
|
Requirements
|
||
|
|
------------
|
||
|
|
|
||
|
|
The first thing you need is a board with an ESP8266 chip. The MicroPython
|
||
|
|
software supports the ESP8266 chip itself and any board should work. The main
|
||
|
|
characteristic of a board is how much flash it has, how the GPIO pins are
|
||
|
|
connected to the outside world, and whether it includes a built-in USB-serial
|
||
|
|
convertor to make the UART available to your PC.
|
||
|
|
|
||
|
|
The minimum requirement for flash size is 512k. A board with this amount of
|
||
|
|
flash will not have room for a filesystem, but otherwise is fully functional.
|
||
|
|
If your board has 1Mbyte or more of flash then it will support a filesystem.
|
||
|
|
|
||
|
|
Names of pins will be given in this tutorial using the chip names (eg GPIO0)
|
||
|
|
and it should be straightforward to find which pin this corresponds to on your
|
||
|
|
particular board.
|
||
|
|
|
||
|
|
Powering the board
|
||
|
|
------------------
|
||
|
|
|
||
|
|
If your board has a USB connector on it then most likely it is powered through
|
||
|
|
this when connected to your PC. Otherwise you will need to power it directly.
|
||
|
|
Please refer to the documentation for your board for further details.
|
||
|
|
|
||
|
|
Deploying the firmware
|
||
|
|
----------------------
|
||
|
|
|
||
|
|
The very first thing you need to do is put the MicroPython firmware (compiled
|
||
|
|
code) on your ESP8266 device. There are two main steps to do this: first you
|
||
|
|
need to put your device in boot-loader mode, and second you need to copy across
|
||
|
|
the firmware. The exact procedure for these steps is highly dependent on the
|
||
|
|
particular board and you will need to refer to its documentation for details.
|
||
|
|
|
||
|
|
If you have a board that has a USB connector, a USB-serial convertor, and has
|
||
|
|
the DTR and RTS pins wired in a special way then deploying the firmware should
|
||
|
|
be easy as all steps can be done automatically. Boards that have such features
|
||
|
|
include the Adafruit Feather HUZZAH and NodeMCU boards.
|
||
|
|
|
||
|
|
For best results it is recommended to first erase the entire flash of your
|
||
|
|
device before putting on new MicroPython firmware.
|
||
|
|
|
||
|
|
Currently we only support esptool.py to copy across the firmware. You can find
|
||
|
|
this tool here: `<https://github.com/themadinventor/esptool/>`__ . Any other
|
||
|
|
flashing program should work, so feel free to try them out, or refer to the
|
||
|
|
documentation for your board to see its recommendations.
|
||
|
|
|
||
|
|
Using esptool.py you can erase the flash with the command::
|
||
|
|
|
||
|
|
esptool.py --port /dev/ttyUSB0 erase_flash
|
||
|
|
|
||
|
|
And then deploy the new firmware using::
|
||
|
|
|
||
|
|
esptool.py --port /dev/ttyUSB0 --baud 460800 write_flash --flash_size=8m 0 mp-esp8266-firmware.bin
|
||
|
|
|
||
|
|
You might need to change the "port" setting to something else relevant for your
|
||
|
|
PC. You may also need to reduce the baudrate if you get errors when flashing
|
||
|
|
(eg down to 115200).
|
||
|
|
|
||
|
|
If you have a NodeMCU board, you may need to use the following command to deploy
|
||
|
|
the firmware (note the "-fm dio" option)::
|
||
|
|
|
||
|
|
esptool.py --port /dev/ttyUSB0 --baud 460800 write_flash --flash_size=8m -fm dio 0 mp-esp8266-firmware.bin
|
||
|
|
|
||
|
|
If the above commands run without error then MicroPython should be installed on
|
||
|
|
your board!
|
||
|
|
|
||
|
|
Serial prompt
|
||
|
|
-------------
|
||
|
|
|
||
|
|
Once you have the firmware on the device you can access the REPL (Python prompt)
|
||
|
|
over UART0 (GPIO1=TX, GPIO3=RX), which might be connected to a USB-serial
|
||
|
|
convertor, depending on your board. The baudrate is 115200. The next part of
|
||
|
|
the tutorial will discuss the prompt in more detail.
|
||
|
|
|
||
|
|
WiFi
|
||
|
|
----
|
||
|
|
|
||
|
|
After a fresh install and boot the device configures itself as a WiFi access
|
||
|
|
point (AP) that you can connect to. The ESSID is of the form MicroPython-xxxxxx
|
||
|
|
where the x's are replaced with part of the MAC address of your device (so will
|
||
|
|
be the same everytime, and most likely different for all ESP8266 chips). The
|
||
|
|
password for the WiFi is micropythoN (note the upper-case N). Its IP address
|
||
|
|
will be 192.168.4.1 once you connect to its network. WiFi configuration will
|
||
|
|
be discussed in more detail later in the tutorial.
|