--- Title: Getting started with MicroPython and ESP8266 Description: Getting started with MicroPython and ESP8266 Slug: esp8266-and-micropython-guide Listing: true Created: 2020, September 6 Tags: [] --- **Table of contents** 1. [Introduction](#introduction) 2. [Flashing the SOC](#flashing-the-soc) 3. [Install better tooling](#install-better-tooling) 4. [Additional resources](#additional-resources) ## Introduction A while ago I bought some [ESP8266](https://www.espressif.com/en/products/socs/esp8266) and [ESP32](https://www.espressif.com/en/products/socs/esp32) dev boards to play around with and I finally found a project to try it out. For my project, I used [ESP32](https://www.espressif.com/en/products/socs/esp32) but I could easily choose [ESP8266](https://www.espressif.com/en/products/socs/esp8266). This guide contains which tools I use and how I prepared my workspace to code for [ESP8266](https://www.espressif.com/en/products/socs/esp8266). ![ESP8266 and ESP32 boards](/assets/esp8366-micropython/boards.jpg) This guide covers: - flashing SOC - install proper tooling - deploying a simple script > Make sure that you are using **a good USB cable**. I had some problems with mine and once I replaced it everything started to work. ## Flashing the SOC Plug your ESP8266 to USB port and check if the device was recognized with executing `dmesg | grep ch341-uart`. Then check if the device is available under `/dev/` by running `ls /dev/ttyUSB*`. > **Linux users**: if a device is not available be sure you are in `dialout` group. You can check this by executing `groups $USER`. You can add a user to `dialout` group with `sudo adduser $USER dialout`. After these conditions are meet go to the navigate to [https://micropython.org/download/esp8266/](https://micropython.org/download/esp8266/) and download `esp8266-20200902-v1.13.bin`. ```sh mkdir esp8266-test cd esp8266-test wget https://micropython.org/resources/firmware/esp8266-20200902-v1.13.bin ``` After obtaining firmware we will need some tooling to flash the firmware to the board. ```sh sudo pip3 install esptool ``` You can read more about `esptool` at [https://github.com/espressif/esptool/](https://github.com/espressif/esptool/). Before flashing the firmware we need to erase the flash on device. Substitute `USB0` with the device listed in output of `ls /dev/ttyUSB*`. ```sh esptool.py --port /dev/ttyUSB0 erase_flash ``` If flash was successfully erased it is now time to flash the new firmware to it. ```sh esptool.py --port /dev/ttyUSB0 --baud 460800 write_flash --flash_size=detect 0 esp8266-20200902-v1.13.bin ``` If everything went ok you can try accessing MicroPython REPL with `screen /dev/ttyUSB0 115200` or `picocom /dev/ttyUSB0 -b115200`. > Sometimes you will need to press `ENTER` in `screen` or `picocom` to access REPL. When you are in REPL you can test if all is working properly following steps. ```py > import machine > machine.freq() ``` This should output a number representing a frequency of the CPU (mine was `80000000`). When you are in `screen` or `picocom` these can help you a bit. | Key | Command | | -------- | -------------------- | | CTRL+d | preforms soft reboot | | CTRL+a x | exits picocom | | CTRL+a \ | exits screen | ## Install better tooling Now, to make our lives a little bit easier there are couple of additional tools that will make this whole experience a little more bearable. There are twq cool ways of uploading local files to SOC flash. - ampy → [https://github.com/scientifichackers/ampy](https://github.com/scientifichackers/ampy) - rshell → [https://github.com/dhylands/rshell](https://github.com/dhylands/rshell) ### ampy ```bash # installing ampy sudo pip3 install adafruit-ampy ``` Listed below are some common commands I used. ```bash # uploads file to flash ampy --delay 2 --port /dev/ttyUSB0 put boot.py # lists file on flash ampy --delay 2 --port /dev/ttyUSB0 ls # outputs contents of file on flash ampy --delay 2 --port /dev/ttyUSB0 cat boot.py ``` > I added `delay` of 2 seconds because I had problems with executing commands. ### rshell Even though `ampy` is a cool tool I opted with `rshell` in the end since it's much more polished and feature rich. ```bash # installing ampy sudo pip3 install rshell ``` Now that `rshell` is installed we can connect to the board. ```bash rshell --buffer-size=30 -p /dev/ttyUSB0 -a ``` This will open a shell inside bash and from here you can execute multiple commands. You can check what is supported with `help` once you are inside of a shell. ```bash m@turing ~/Junk/esp8266-test $ rshell --buffer-size=30 -p /dev/ttyUSB0 -a Using buffer-size of 30 Connecting to /dev/ttyUSB0 (buffer-size 30)... Trying to connect to REPL connected Testing if ubinascii.unhexlify exists ... Y Retrieving root directories ... /boot.py/ Setting time ... Sep 06, 2020 23:54:28 Evaluating board_name ... pyboard Retrieving time epoch ... Jan 01, 2000 Welcome to rshell. Use Control-D (or the exit command) to exit rshell. /home/m/Junk/esp8266-test> help Documented commands (type help ): ======================================== args cat connect date edit filesize help mkdir rm shell boards cd cp echo exit filetype ls repl rsync Use Control-D (or the exit command) to exit rshell. ``` > Inside a shell `ls` will display list of files on your machine. To get list of files on flash folder `/pyboard` is remapped inside the shell. To list files on flash you must perform `ls /pyboard`. #### Moving files to flash To avoid copying files all the time I used `rsync` function from the inside of `rshell`. ```bash rsync . /pyboard ``` #### Executing scripts It is a pain to continuously reboot the device to trigger `/pyboard/boot.py` and there is a better way of testing local scripts on remote device. Lets assume we have `src/freq.py` file that displays CPU frequency of a remote device. ```py # src/freq.py import machine print(machine.freq()) ``` Now lets upload this and execute it. ```bash # syncs files to remove device rsync ./src /pyboard # goes into REPL repl # we import file by importing it without .py extension and this will run the script > import freq # CTRL+x will exit REPL ``` ## Additional resources - [https://randomnerdtutorials.com/getting-started-micropython-esp32-esp8266/](https://randomnerdtutorials.com/getting-started-micropython-esp32-esp8266/) - [http://docs.micropython.org/en/latest/esp8266/quickref.html](http://docs.micropython.org/en/latest/esp8266/quickref.html)