Python programming for arduino

As a software developer who has a passion for electronics and astronomy, he started one of the first projects to control a telescope with the Arduino microcontroller by using acomputer w

Python Programming for Arduino

Prototyping templates using Firmata

Potentiometer – continuous observation from an analog inputConnections

Prototyping with the I2C protocol

Arduino examples for I2C interfacing

Arduino coding for the TMP102 temperature sensorArduino coding for the BH1750 light sensor

The close() method

The read() method

The with statement – Python context managerUsing CSV files to store data

Plotting percentage humidity using matplotlib

Using button interrupts to control the parameters

Changing the temperature unit by pressing a buttonSwapping between the GUI and the plot by pressing a buttonTroubleshooting

Stage 2 – using a Raspberry Pi for the deployable thermostat

What is a Raspberry Pi?

Installing the operating system and configuring the Raspberry PiWhat do you need to begin using the Raspberry Pi?

Uploading data using a web interface based on web.pyPython – downloading data from Xively

The basic method for retrieving data from XivelyRetrieving data from the web.py web interface

10 The Final Project – a Remote Home Monitoring SystemThe design methodology for IoT projects

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Copyright © 2015 Packt Publishing

All rights reserved No part of this book may be reproduced, stored in a retrieval system,

or transmitted in any form or by any means, without the prior written permission of thepublisher, except in the case of brief quotations embedded in critical articles or reviews.Every effort has been made in the preparation of this book to ensure the accuracy of theinformation presented However, the information contained in this book is sold withoutwarranty, either express or implied Neither the author, nor Packt Publishing, and its

dealers and distributors will be held liable for any damages caused or alleged to be causeddirectly or indirectly by this book

Manu Joseph

Pratik Desai, PhD, is the Principal Scientist and cofounder of a connected devices start-up, Imbue Labs, where he develops scalable and interoperable architecture for wearabledevices and Internet of Things (IoT) platforms during the day At night, he leads the

development of an open source IoT initiative, the Semantic Repository of Things Pratikhas 8 years of research and design experience in various layers of the IoT and its

predecessor technologies such as wireless sensor networks, RFID, and machine-to-machine (M2M) communication His domains of expertise are the IoT, Semantic Web,machine learning, robotics, and artificial intelligence

Pratik completed his MS and PhD from Wright State University, Ohio, and collaboratedwith the Ohio Center of Excellence in Knowledge-enabled Computing (Kno.e.sis) duringhis doctoral research His doctoral research was focused on developing situation

awareness frameworks for IoT devices, enabling semantic web-based reasoning and

handling the uncertainty associated with sensor data

In his personal life, Pratik is an avid DIY junkie and likes to get hands-on experience onupcoming technologies He extensively expresses his views on technology and sharesinteresting developments on Twitter (@chheplo)

I would like to dedicate the book to my parents, who were responsible for building thefoundation of what I am today The book would not have been possible without the

patience, support, and encouragement from my beloved wife, Sachi I would also like tothank her for landing her photography skills that were used in development of some of theimportant images used in the book I would also like to extend my sincere gratitude to theeditors for their valuable feedbacks

Juan Ramón González is a technical engineer of computer systems and lives in Seville

(Andalusia, Spain) For the past 9 years, he has been working on free software-basedprojects for the regional Ministry of Education by using Python, C++, and JavaScript,among other programming languages

He is one of the main members of the CGA project in Andalusia (Centro de Gestión

Avanzado or Advanced Management Center), which manages a network with more than4,000 servers with Debian and 500,000 client computers that run Guadalinex, a

customized Ubuntu-based operating system for Andalusian schools

As a software developer who has a passion for electronics and astronomy, he started one

of the first projects to control a telescope with the Arduino microcontroller by using acomputer with the Stellarium software and a driver developed with Python to

communicate with the telescope This project’s sources are published on the collaborativeplatform GitHub You can see the whole code and the prototype at

He runs several websites around Arduino, including the Open Home Automation websitethat is dedicated to building home automation systems using open source hardware

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In the era of the Internet of Things (IoT), it has become very important to rapidly developand test prototypes of your hardware products while also augmenting them using softwarefeatures The Arduino movement has been the front-runner in this hardware revolution,and through its simple board designs it has made it convenient for anyone to develop DIYhardware projects The great amount of support that is available through the open sourcecommunity has made the difficulties that are associated with the development of a

hardware prototype a thing of the past On the software front, Python has been the crownjewel of the open source software community for a significant amount of time Python issupported by a huge amount of libraries to develop various features, such as graphical userinterfaces, plots, messaging, and cloud applications

This book tries to bring you the best of both hardware and software worlds to help youdevelop exciting projects using Arduino and Python The main goal of the book is to assistthe reader to solve the difficult problem of interfacing Arduino hardware with Pythonlibraries Meanwhile, as a secondary goal, the book also provides you with exercises andprojects that can be used as blueprints for your future IoT projects

The book has been designed in such a way that every successive chapter has increasingcomplexity in terms of material that is covered and also more practical value The bookhas three conceptual sections (getting started, implementing Python features, and networkconnectivity) and each section concludes with a practical project that integrates the

concepts that you learned in that section

The theoretical concepts and exercises covered in the book are meant to give you hands-on experience with Python-Arduino programming, while the projects are designed to teachyou hardware prototyping methodologies for your future projects However, you will stillneed extensive expertise in each domain to develop a commercial product In the end, Ihope to provide you with sufficient knowledge to jump-start your journey in this noveldomain of the IoT

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to create your first Python-Arduino project, which controls different LEDs according tothe detected motion

Chapter 8, Introduction to Arduino Networking, introduces computer networking for

Arduino while utilizing various protocols to establish Ethernet communication betweenthe Python program and Arduino This chapter also explores a messaging protocol calledMQTT, with basic examples This protocol is specifically designed for resource-

To begin with, you will just need a computer with one of the supported operating systems,Windows, Mac OS X, or Linux The book requires various additional hardware

designed for Python 2.7 and they have not been tested against Python 3+

If you are a student, a hobbyist, a developer, or a designer with little or no programmingand hardware prototyping experience and you want to develop IoT applications, then thisbook is for you

If you are a software developer and interested in gaining experience with hardware

domain, this book will help you to get started If you are a hardware engineer who wants

to learn advance software features, this book can help you to begin with

digitalWrite(led, LOW); // turn the LED off by making the voltage LOW delay(1000); // wait for a second

}

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Chapter 1 Getting Started with Python and Arduino

This chapter introduces the Python programming language and the open source electronicprototyping platform Arduino The first section of the chapter focuses on Python andbriefly describes the benefits of Python along with installation and configuration steps.The remaining part of the chapter describes Arduino and Arduino’s development

environment

At the end of this chapter, you will have configured a programming environment for bothPython and Arduino for your favorite operating system If you are a beginner with either

or both platforms (that is, Python and Arduino), it is advisable that you follow the givensteps in this chapter, as the later chapters will assume that you have the exact

configuration described here If you have previous experience of working with theseplatforms, you can skip to the next chapter

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Since its introduction by Guido van Rossum in 1991, Python has grown into one of themost widely used general-purpose, high-level programming languages, and is supported

by one of the largest open source developer communities Python is an open source

programming language that includes a lot of supporting libraries These libraries are thebest feature of Python, making it one of the most extensible platforms Python is a

dynamic programming language, and it uses an interpreter to execute code at runtimerather than using a compiler to compile and create executable byte codes

The philosophy behind the development of Python was to create flexible, readable, andclear code to easily express concepts The emphasis on using whitespace indentation in aunique way differentiates Python from other popular high-level languages Python

supports functional, imperative, and object-oriented programming with automatic memorymanagement

Python is considered to be one of the easiest languages to learn for first-time

programmers Compared to other popular object-oriented languages such as C++ andJava, Python has the following major benefits for programmers:

applications, as well as the development of simple GUI-based applications to plot chartsfrom complex math functions The majority of Python library packages have

systematically maintained the code that was obtained from the community with regularupdates The de facto repository that indexes the largest number of Python packages isPyPI (http://pypi.python.org) PyPI also provides simple ways to install various packages

on your operating system, which will be covered in the upcoming section

While working with the hardware platform, it is necessary to have some means of

communication between the hardware and the computer that you are using for

based communication is the most popular, and it is really simple to establish, especiallyfor the Arduino platform Python provides a library called pySerial that is really easy touse and quick to implement to interface a serial port It is really simple to use similar

development Among the common computer to hardware interfacing methods, serial- port-libraries and Python’s interactive programming abilities to rapidly test and implement yourproject ideas

successful at providing support for these types of applications for years Python has anumber of libraries to support the development of each of the features mentioned here,which are available through PyPI These libraries are open source, easy to use, and widelysupported by the community This makes Python a language of choice for IoT

applications Additionally, Python also has support to create and ship your custom-builtapplications as libraries so that everyone else can also utilize them in their projects This is

a helpful feature if you are developing custom protocols, APIs, or algorithms for your ownhardware products

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