Introduction

If you want to program your ESP32 and ESP8266 with MicroPython firmware, it's very handy to use an IDE. In this guide, we'll introduce you to Thonny IDE. After completing this guide, you'll have your first LED blinking using MicroPython and Thonny IDE.

We've experimented with several IDEs to program the ESP32 and ESP8266 boards using MicroPython, and Thonny IDE is our preference.

It allows you to program your ESP32, ESP8266, Raspberry Pi Pico, and other boards with MicroPython. It is compatible with Windows, Mac OS X, and Linux. It comes installed by default on the Raspberry Pi OS. Additionally, it's easy to install, so you shouldn't have problems with the installation process.

What is MicroPython?

MicroPython is a Python 3 programming language re-implementation targeted for microcontrollers and embedded systems. MicroPython is very similar to regular Python. Apart from a few exceptions, the language features of Python are also available in MicroPython. The most significant difference between Python and MicroPython is that MicroPython was designed to work under constrained conditions.

Because of that, MicroPython does not come with the entire pack of standard libraries. It only includes a small subset of the Python standard libraries, but it includes modules to easily control and interact with the GPIOs, use Wi-Fi, and other communication protocols.

Installing Thonny IDE

In this guide, we provide instructions to install Thonny IDE in different operating systems. Follow the section for the operating system you're using.

• Installing Thonny IDE – Windows PC
• Installing Thonny IDE – Mac OS X
• Installing Thonny IDE – Linux

A) Installing Thonny IDE – Windows PC

To install Thonny on your Windows PC, follow the next instructions:

1. Go to https://thonny.org
2. Download the Installer for Windows and wait a few seconds while it downloads.

3. Run the .exe file.
4. Follow the installation wizard to complete the installation process. You just need to click "Next".

5. After completing the installation, open Thonny IDE. A window should open ready for programming.

B) Installing Thonny IDE – Mac OS X

Since Thonny IDE is open source and downloaded from the Internet, it's not a verified app in the App Store. For security reasons, Mac OS X blocks unknown apps to run on your computer. Follow these next instructions to enable any downloaded software to run in your Mac.

1. Open the "System Preferences..." menu.
2. Open the "Security & Privacy" menu.

3. At the bottom left corner, click the lock icon to modify your "Security & Privacy" settings.

4. Type your username/password and click the "Unlock" button.
5. Select the option "Allow apps downloaded from: Anywhere".

That's it, you can close that window. To install Thonny on Mac OS X, follow the next instructions:

1. Go to https://thonny.org
2. Download the version for Mac OS X and wait a few seconds while it downloads.
3. Open the .dmg file.
4. Drag the "Thonny" application to your Desktop.
5. Thonny IDE is now installed and you can double-click to open it.

C) Installing Thonny IDE – Linux

To install Thonny on your Linux computer, it depends on your Linux distribution and version. First, we recommend installing these dependencies: python3, python3-pip, and python3-tk

If you're in Ubuntu, you can install the Python dependencies like this:

sudo apt install python3 python3-pip python3-tk

After having Python3, pip3, and Python3 Tkinter, you can install Thonny IDE.

Ubuntu:

bash <(wget -O - https://thonny.org/installer-for-linux)

Or install with pip3:

sudo pip3 install thonny

Fedora since 27:

sudo dnf install thonny

Raspbian since Stretch:

sudo apt install python3-thonny

After installing Thonny IDE, to open it:

• You either need go to the search bar and type "Thonny" to find it
• Or if you installed using pip3, you can type in your terminal: thonny

Flashing MicroPython Firmware

MicroPython isn't flashed onto the ESP32 or ESP8266 boards by default. The first thing you need to do to start programming your boards with MicroPython is flash/upload/burn the firmware.

There are different ways in which you can do that. Thonny IDE comes with a tool that allows you to quickly install MicroPython firmware on your board. That's the method we'll use in this tutorial.

Flashing MicroPython Firmware using Thonny IDE

In this section, you'll learn how to flash MicroPython firmware on your boards using Thonny IDE. Follow the next steps:

1. Connect your ESP32 or ESP8266 board to your computer.
2. Open Thonny IDE. Go to Tools > Options > Interpreter.
3. Select the interpreter you want to use accordingly to the board you're using and select the COM port your board is connected to. Finally, click on the link Install or update MicroPython.

4. Then, select the port once again, the board you're using, and the variant. It will automatically pick up the most recent MicroPython firmware version. Finally, you can click Install.

5. After a few seconds, the installation should be completed. If you're using an ESP32, you may need to press the BOOT button for a few seconds after clicking the Install button.
6. When the installation is completed, you can close the window. You should get a message on the Shell, and at the bottom right corner, it should have the Interpreter it's using and the COM port.

The REPL

You should also see the >>> symbol (if you don't, click on the Stop icon at the top).

This symbol represents the MicroPython REPL (Read-Eval-Print-Loop) prompt. This symbol means you're interacting with MicroPython (the board with MicroPython firmware installed) in interactive mode in real time. This simply means that you can enter and execute commands directly.

Testing the Installation

Type help() in the Shell after the prompt >>> and see if your device responds.

It should print some useful information about programming your board using MicroPython. You can test other commands. For example, type the following:

>>> print('Hello')

It should print Hello on the Shell right after you enter the command.

You can also run the following commands successively on the Shell after the prompt (>>>) one at a time to turn on the ESP32/ESP8266 built-in LED.

>>> from machine import Pin
>>> led = Pin(2, Pin.OUT)

If you're using an ESP32, turn the onboard LED as follows:

>>> led.value(1)

If you're using an ESP8266, the built-in LED works with inverted logic. So, you turn it on as follows:

>>> led.value(0)

The on-board LED should light up.

Thonny IDE Overview

At this point, you should have:

• Thonny IDE installed on your computer
• ESP32/ESP8266 flashed with MicroPython firmware

Open Thonny IDE. There are two different sections: the Editor and the MicroPython Shell/Terminal:

• The Editor section is where you write your code and edit your .py files. You can open more than one file, and the Editor will open a new tab for each file.
• In the MicroPython Shell, you can type commands to be executed immediately by your ESP board without the need to upload new files. The terminal also provides information about the state of an executing program, shows errors related to the uploading process, syntax errors, prints messages, etc.

Running Your First Script – Blinking an LED

To get you familiar with the process of writing a file and executing code on your ESP32/ESP8266 boards, we'll upload a new script that simply blinks the on-board LED of your ESP32 or ESP8266.

When you open Thonny IDE for the first time, the Editor shows an untitled file. Copy the following script to that file:

from machine import Pin
from time import sleep
led = Pin(2, Pin.OUT)
while True:
  led.value(not led.value())
  sleep(0.5)

Running the Script

To run that script on your board, simply click on the Run icon in Thonny IDE.

The on-board LED will start blinking.

To stop the execution of the program, you can hit the STOP button or simply press CTRL+C.

Running your Code Automatically

Just running the file with Thonny doesn't copy it permanently to the ESP32 or ESP8266 filesystem. This means that if you unplug it from your computer and apply power to the board, nothing will happen because it doesn't have any MicroPython file saved on its filesystem.

The Thonny IDE Run function is useful to test the code, but if you want to upload it permanently to your board, you need to create and save a file to the board's filesystem.

Uploading Code to the ESP32/ESP8266 Boards

Stop the execution of the previous program by clicking on the Stop button if you haven't already.

1. With the code copied to the file, click on the Save icon or go to File > Save as…
2. Then, select MicroPython device.
3. Name the file main.py, otherwise, it will not run automatically on the ESP32 or ESP8266.

4. Finally, click Ok to proceed.

5. Now, press the on-board RST/EN button so that the board restarts and starts running the code.
6. Now, your board should be blinking the blue on-board LED every 500 milliseconds.

After saving the file, you can remove and apply power again to the board, or you can even power it using a different power supply that is not your computer.

Notice that the board will automatically start blinking the LED when you apply power to it. This means the main.py file was successfully uploaded to the board and that it is running that file automatically.

Congratulations! You've just written and uploaded your first MicroPython script to your ESP32/ESP8266 board.

Troubleshooting Tips for Thonny IDE

We've discovered some common problems and error messages that occur with Thonny IDE. Usually restarting your ESP with the on-board EN/RST button fixes your problem. Or press the Thonny IDE "Stop/Restart backend" button and repeat your desired action. In case it doesn't work for you, read these next common errors and discover how to solve them.

Wrapping Up

Thonny IDE is a great IDE to program the ESP32 and ESP8266 boards using MicroPython. It is compatible with Windows, Mac OS X, and Linux, and it is easy to install.

This tutorial covered:

• Installing Thonny IDE on different operating systems
• Flashing MicroPython firmware to ESP32/ESP8266
• Testing the installation and running your first script
• Uploading code permanently to your board
• Common troubleshooting tips

With Thonny IDE and MicroPython, you're now ready to start building amazing projects with your ESP32 and ESP8266 boards!