Introduction
Prerequisites
to follow this manual you need to install Anaconda and Eclipse, and set up Eclipse for Python.
Media sources
These youtube lessons are too lengthy (American) the same stuff i regurgitated a dozen times and you never get anywhere. But anyway. 1 https://www.youtube.com/watch?v=95w4sx_zoB8
2 https://www.youtube.com/watch?v=mF5cE3DS50s&list=PLGs0VKk2DiYylFUUMMv9WiL3x3tpscDUQ
https://www.youtube.com/watch?v=d8_xXNcGYgo
Prototyping Arduino Projects using Python
Virtual Conda environment for Arduino Python
I run all my Python projects as Conda virtual environments. To set up an environment for Arduino Python, start the Terminal.
The general command for creating a conda virtual environment is:
$ conda create –name arduino_XX
If you want to specify which version of python to install and the packages to start with, the command can be extended (see the conda page on Managing environments for details):
$ conda create –n arduino_01 python=3.6 numpy
If you have .condarc file defining a set of default packages and do not want to include them in your arduino environment, then add the command –no-default-packages:
$ conda create –no-default-packages –n arduino_01 python=3.6 numpy
It is always best to install all (or as many as possible) of the packages that are needed for your environment in one go. Conda will then automatically resolve any dependency conflicts. For my arduino environment I wanted the following packages:
- pip
- pyfirmata
- time
As this is my first trial, I do not know about versions, so I will just go for the defaults in Python 3.6. The (theoretical) command for creating my virtual Python envirnment for Arduino Python thus becomes:
$ conda create –no-default-packages –n arduino_01 python=3.6 pip pyfirmata time
But that does not work, I get error messages. It might have to do with my .condarc file (or lack of this file). Having tried various commands I ended up with this stripped version:
$ conda create -n arduino_01 python=3.6 pip
And then the command (finally!)) went through. The terminal window reports what is happening, then stops and prompts for an answer whether to Proceed or not:
The following NEW packages will be INSTALLED:
ca-certificates pkgs/main/osx-64::ca-certificates-2019.11.27-0
certifi pkgs/main/osx-64::certifi-2019.11.28-py36_0
libcxx pkgs/main/osx-64::libcxx-4.0.1-hcfea43d_1
libcxxabi pkgs/main/osx-64::libcxxabi-4.0.1-hcfea43d_1
libedit pkgs/main/osx-64::libedit-3.1.20181209-hb402a30_0
libffi pkgs/main/osx-64::libffi-3.2.1-h475c297_4
ncurses pkgs/main/osx-64::ncurses-6.1-h0a44026_1
openssl pkgs/main/osx-64::openssl-1.1.1d-h1de35cc_3
pip pkgs/main/osx-64::pip-19.3.1-py36_0
python pkgs/main/osx-64::python-3.6.10-h359304d_0
readline pkgs/main/osx-64::readline-7.0-h1de35cc_5
setuptools pkgs/main/osx-64::setuptools-44.0.0-py36_0
sqlite pkgs/main/osx-64::sqlite-3.30.1-ha441bb4_0
tk pkgs/main/osx-64::tk-8.6.8-ha441bb4_0
wheel pkgs/main/osx-64::wheel-0.33.6-py36_0
xz pkgs/main/osx-64::xz-5.2.4-h1de35cc_4
zlib pkgs/main/osx-64::zlib-1.2.11-h1de35cc_3
Proceed ([y]/n)?
Just the the Y key and install. Once finished, change to the virtual environment at the terminal:
$ conda activate arduino_01<(span)>
If all has worked out, the terminal line should start the command line text with the name of the your environment in parenthesis: (arduino_01)<(span)>
Install additional packages
As I did not manage to install the packages I wanted when creating the virtual environment, I need to do that while the new environment (arduino_01) is active. Going though the list of packages, here is how to install them at time of writing this manual (January 2020):
pyfirmata
[pyFirmata][https://pypi.org/projects/pyFirmata/] is a Python interface for the Firmata protocol. Firmata protocol is for communicating with microcontrollers from software on a computer (or smartphone/tablet, etc). The protocol can be implemented in firmware on any microcontroller architecture as well as software on any computer software package (see list of client libraries below).
$ conda install -c conda-forge pyfirmata<(span)>
pyserial
$ conda install -c anaconda pyserial<(span)>
time
$ conda install -c conda-forge time<(span)>
tkinter
$ conda install tk<(span)>
Eclipse
I use Eclipse for writing my Python scripts. As stated in the Prerequistists you have to have Eclipse installed.
Define Python interpreter
In the Eclipse menu select:
In the left column expand Pydev and Python Interpreter (as shown in the figure below). Click the button for and navigate to the virtual environments under your Anaconda installation (also shown). Select the python program file and click in the Select interpreter window. With all options selected (default), also click in the Selection needed window that pops up. When finished click the button in the Preferences window.
Create Project
From the Eclipse menu select:
In the wizard for PyDev project, keep all the default entries and just add a Project Name.
When you click , Eclipse will ask if you want to change to the Python perspective, accept that suggestion.
Create package and module
With Eclipse setup and prepared for Python, and your project defined, create a python package (shown in the figure below) and then a python module. Create both from the menu:
Test packages
Small test script that utilizes the packages you installed in your virtual environment:
import pyfirmata
import time
board = pyfirmata.Arduino('/dev/ttyACM0')
while True:
board.digital[13].write(1)
time.sleep(1)
board.digital[13].write(0)
time.sleep(1)
Try to run the script.
If the script compiles you are fine. As you (probably) do not have any Arduino board attached, the script will report an error not finding the board, but that is OK for now.
Arduino test
With the system setup you can search for online manuals that will take you through the details of how to run Arduino Python.
Arduino With Python: How to Get Started
How to Program and Control an Arduino With Python
This manual uses pyserial instead of pyfirmata: