Arduino: Cheat sheet

This comprehensive guide covers everything you need to know about Arduino, a project to ease people into creating their own DIY gadgets and electronic art.

If you've ever had a hankering to make your own electronics, then buying an Arduino board and getting stuck into a tutorial is as good place as any to start.

This guide and accompanying video will walk you through everything you need to know to get started with Arduino, and will be updated over time.

SEE: All of TechRepublic's cheat sheets and smart person's guides

Executive summary

  • What is Arduino? A project that provides hardware, software and community support for people who want to create DIY electronics.
  • Why does Arduino matter? Because it makes it simpler for people with a non-technical background to make their own gadgets.
  • Who does Arduino affect? Anyone interested in tinkering with electronics and using them to create devices or works of art.
  • Who are Arduino's competitors? Arduino has inspired a huge number of spin-off boards, due to its open design, which cater to a wide range of electronics hobbyists.
  • When is Arduino happening? Right now, it's an ongoing project with new Arduino boards being released on regular basis.
  • Where is Arduino available? The boards, kits and components are widely available online, from non-specialists store such as Amazon and specialist stories such as Adafruit in the US and element14 in the UK, as well as the official Arduino store.

What is Arduino?

The Arduino project provides a simple way for people to get started creating their own homemade gadgets.

The project offers all the ingredients that budding electronics hobbyists need: the hardware, software, and an active community to help new users via forums and online tutorials.

Arduino lends its name to a range of programmable microcontroller boards, which serve as the brains of these DIY devices. These boards can be wired into makeshift circuits, where they can interact with lights, sensors, motors, microphones, buttons, and any other component you want to include in your homespun appliances. For instance, you could use an Arduino to build a motion-controlled video camera or to remote control the lights in your sitting room.

Of course, all this hardware is no good without a way to control it. Fortunately Arduino boards are programmable from a Linux, Mac or Windows machine, using a integrated development environment (IDE), downloadable from here, or from the Arduino web editor.

This IDE lets users write programs called Sketches, which can interact with the board and any attached components via its onboard pins, for example sending a signal from the pin to an LED to make it flash or reading off an input from a pin that is connected to a sensor.

Starting from these very simple creations, users can build complex electronics, eventually working their way up to the likes of robot arms or fingerprint scanners, and more importantly their own unique creations, for instance a tooth-brushing robot.

Once the Sketch is complete, the IDE will transform it a form that can be understood by the board, first into C++ and compiling it down into machine instructions. These instructions can then be uploaded to the board via USB.

While writing programs for Arduino might sound daunting, the basics are relatively straightforward, with each Sketch program requiring the user to set up the board to send signals to or collect signals from its pins and the connected components, and then to instruct the board on how to interact with these components.

The Arduino language is basically a simplified version of the C++ programming language, and requires some basic knowledge of programming constructs, such as variables, functions, loops and constants. However, there is also a lot of pre-built code for common tasks, such as writing to storage or controlling servo motors, which you can drop straight into your program by importing libraries.

I'll walk you through setting up the board and a simple program in the video above. There is obviously far more complexity to get to grips with as you progress, but luckily there are a lot of tutorials and an active community to help you.

Additional resources

Why does Arduino matter?

The ethos of the Arduino is to simplify the process of making electronics, to make it accessible to people who don't have a technical background.

As the project page itself says, Arduinos are designed so that "anyone - children, hobbyists, artists, programmers - can start tinkering just following the step by step instructions of a kit, or sharing ideas online with other members of the Arduino community".

Much of this ease of use stems from the large ecosystem of boards and kits that have grown up over time and the swathes of tutorials and code produced by an active community, who are willing to help newcomers via the official forums.

That desire to broaden the appeal of electronics was what what led to the creation of the Arduino project, back in the mid 2000s, when the first board was produced at the Ivrea Interaction Design Institute in Italy, as a tool to allow students without a technical background to rapidly prototype electronics.

Additional resources

Who does Arduino affect?

The accessibility of the Arduino project has given the boards broad appeal. Arduinos are used by those new to electronics—teachers, artists and children—as well as those with expertise in electronics and programming.

Getting started with Arduino might seem overwhelming at first, due to the sheer number of boards available, with more than 20 official offerings that are typically built around Atmel AVR microcontrollers, and that's not counting clone or "Arduino-compatible" boards.


The Arduino Uno is a great board to get started with.

Image: Arduino

The reason there are so many Arduino-inspired spin-offs is that the designs for the Arduino boards are available to anyone to use under a Creative Commons Attribution Share-Alike licence.

This open-source hardware model not only helps people to study and learn about the boards, but also to tweak those designs and create their own spin-off Arduino clones, which can be cheaper than official boards and / or add new functionality. However, it's worth checking they're 100% compatible with the official boards before picking them up.

Each board has its own flavor, for instance, while the Arduino Robot is a wheeled offering with dedicated boards for driving motors and reading sensors, the Arduino Mega is a single board that ramps up the number of pins to 56 for use in more complex projects.

However, the Arduino organization handily categorizes its boards, splitting them into tiers that denote which board is most likely to suit your needs. If you're outside of the US, official Arduino boards are sometimes sold under the Genuino brand name.

A good choice for beginners is the Arduino Uno, which is a bit of an all-rounder, relatively cheap (€20 or about $22), with enough digital and analog pins to get you started on building electronics, and a raft relevant tutorials available online.

Adding new features to the board can be straightforward, with the easiest option being to use a shield, an expansion board that slots directly into the Arduino's pin headers. Shields can add an array of features, ranging from Zigbee wireless connectivity or an SD card reader.

You'll also need to pick up the electronic components you want to interact with. For newcomers there are many different starter packs available that bundle together an Uno with LEDs, motors, resistors, capacitors, sensors, push buttons and everything else you need to get started. You won't even need to bust out the soldering iron to piece these together, as you can use a breadboard, a plug board that allows electronic components to be easily wired together into circuits with the Arduino.

Once you become more familiar with using the Uno or outgrow its capabilities, you can progress to using one of the many other Arduino boards available, for instance once you've prototyped your electronics, you might want to build the tiny Pro Mini into the final device.

If you want to see what's possible using Arduino, then check out the official Project Hub, where you'll find stair-climbing robots, Harry Potter's Sorting Hat brought to life, IoT-enabled hydroponic farms, a personal healthcare assistant powered by Amazon Alexa, drones, nightmarish hexapod robots, ultrasonic mapping tools, home automation kits, a picture that changes to reflect the weather — the list goes on.

While an Uno board is relatively affordable, the price can quickly mount. Fancier boards, like the Arduino Robot can sell for more than €150, and an official starter kit with everything you need to get started is €80, and if you get hooked, you're likely to continue to accrue new hardware. As mentioned, there is a plethora of clone boards out there that are much cheaper, though it is worth checking they are 100% compatible before buying.

Additional resources

Who are the Arduino's competitors?

While the $35 Raspberry Pi is often mentioned in the same breath as Arduino, due to its superficially similar appearance and equally low price tag, there are significant differences between the Arduino and the Pi. Arduinos are based around microcontrollers and Raspberry Pi is based around a microprocessor connected to on-board RAM and other features. While both boards can control electronics attached to their pins, the Pi is also capable of being run as a full desktop computer. However, the Arduino arguably has the advantage of being simpler to use to make electronic prototypes, and also to swap out for a new microcontroller in the final product.

However, there are a huge number of boards aimed at electronics hobbyists, which are compatible with the Arduino to some extent. These spin-off boards riff on the Arduino in every conceivable way, adding or cutting functionality, lowering or upping power consumption, some cheaper, some more expensive. Basically if you've got an idea for an electronics project, chances are there's an Arduino-inspired board to suit your need.

Additional resources

When is Arduino happening?

Right now, it's an ongoing project with new Arduino boards being released on a regular basis.

Additional resources

Where is Arduino available?

The boards, kits and components are widely available online, from non-specialists store such as Amazon and specialist stories such as Adafruit in the US and element14 in the UK, as well as the official Arduino store.

Additional resources

About Nick Heath

Nick Heath is chief reporter for TechRepublic. He writes about the technology that IT decision makers need to know about, and the latest happenings in the European tech scene.

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