What is MicroPython?

Posted on Fri 29 March 2019 in Python • 2 min read

From the MicroPython docs themselves “MicroPython is a lean and efficient implementation of the Python 3 programming language that includes a small subset of the Python standard library and is optimised to run on microcontrollers and in constrained environments.”. But what does all this mean? Python 3 is one of the most widely used, easy to write/read programming languages in the world that is rapidly growing. By default Python comes with a ‘standard library’ which includes basic functions such as if statements, loops, printing, etc.

Where MicroPython comes in is that the standard library for Python might take up valuable space/computations to run as efficiently it does on a PC, so MicroPython is a slice of the standard library that is able to run more efficiently and take up less space on a microcontroller (RAM and space is crucial when working with microcontrollers).

MicroPython also comes with an interactive REPL (Read-Evaluate-Print Loop), which is an often overlooked amazing feature of MicroPython. The REPL allows you to connect to a microcontroller, execute code quickly without the need to compile or upload code. Which gives immediate feedback on whether your program is working as intended.

Differences between MicroPython & Python

There obviously had to be some changes between Python and MicroPython to make it work efficiently on processors a fraction of the power, but what are they? If you are a beginner-intermediate Python programmer, you’ll only run into trouble in very specific scenarios, which can be easily worked around. For example you cannot delete from a list with a step greater than 1.

Sample Python Code

L = [1,2,3,4]

You’d expect for the output here in Python normally to be:

Python Output MicroPython Output
[2,4] TypeError: object 'range' isn't a tuple or list

However this can be easily worked around with an explicit loop for example:

Sample MicroPython/Python Code

L = [1,2,3,4]
for i in L:

For more information on differences between Python (in particular CPython) and MicroPython you can find the MicroPython documentation here: http://docs.micropython.org/en/latest/genrst/index.html