The world of Arduino

Over the last year or so, our Arduino Masterclass has been hugely popular, but if you’re not sure what all the fuss is about, here’s your chance to get in on the ground floor. Arduino is the world’s cheapest and most popular DIY computer system. It allows you to write incredibly efficient software code or ‘sketches’, program them into the Arduino’s flash memory and run in all manner of embedded applications – single- or multi-function situations that don’t need the complexity of a PC.

Arduino is the perfect way to combine learning computer programming and how to interact with real world objects like lights, motors and switches. But it’s also a great first step into the wider world of electronics design. Through Arduino, you can build everything from automated Twitter clients to robots to complex projects like 3D printers, multi-rotor RC copters and even an Arduino-powered mobile phone.

The two key parts are the Arduino microcontroller board and the integrated development environment or IDE.

Introducing Arduino boards

Since its creation in 2005 by a band of dedicated Italian university lecturers, Arduino has expanded into numerous models, many of which are available at very low cost on eBay. Here are the main ones we’ll look at.

Arduino clones

All Arduino boards (except for the Intel Galileo) are open-source, so you’re free to make and sell your own. That means the majority of boards on eBay are clones, but that’s fine as we’ve used many clone boards and they work perfectly well. Why use clone boards? Price – complete pre-built, ready-to-go clone boards start from under around $8 – and that’s including shipping!

Arduino Shields

The key to Arduino’s success is undoubtedly its expansion port or ‘shield header’, which allows you to plug in expansion boards or shields providing extra functions, everything from motor drivers and alphanumeric LCDs to 3D printer power boards and mobile phone modules. There are even blank prototyping shields that allow you to roll your own designs. The key to using shields is ensuring you include any required libraries in your sketch to make them work.

Vital ingredient: your imagination

If you have a project in mind or something you want to build, chances are there’s an Arduino board that will fit the bill nicely. The only thing you need to add is your imagination. Arduino won’t turn you into an electrical engineer overnight, but it’s a great way to open the door into the world of electronics, become an engineer and design the products of tomorrow.

What’s available

Interested in getting started with Ardunio? Here are some of your options.

Arduino Uno


The Arduino Uno, the most well-known Arduino microcontroller board.

Price: from $14 (eBay)

The most recognisable Arduino is the Uno and like most early Arduino boards, it runs Atmel’s 8-bit/16MHz microcontroller chip called the ATMEGA328P. It’s incredibly modest by PC standards but enough for the vast majority of projects. You get 2KB of RAM, 32KB of flash storage and 20 input/output (I/O) pins (14 digital and six analog) to connect to the real world.

Arduino Nano


The Arduino Nano uses the same chip as the Arduino Uno.

Price: from $8 (eBay)

The Nano is an ultra-compact version of the Uno, with the same chip, built-in USB controller and about the size of a small USB flash drive. It doesn’t support expansion boards or shields like the Uno but it has the same electrical characteristics and performance. Well, not quite – it gives you two more analog inputs compared with the Uno. Not bad for such a tiny board.

Arduino Leonardo


The Arduino Leonardo offers new USB functionality.

Price: from $10 (eBay)

The Leonardo is the replacement for the Uno and features a new ATMEGA32U4 microcontroller, which integrates the USB controller into the chip itself, making it cheaper to produce. It has the same basic 16MHz/8-bit performance but features 2.5KB of RAM. Integrating the USB controller means you get more functionality and greater ability to integrate it with PC USB ports.

Arduino Micro


The tiny new Arduino Micro is a miniaturised Leonardo.

Price: from $8 (eBay)

The Micro is the ultra-compact version of the Leonardo, using the same ATMEGA32U4 chip. It’s actually smaller than the Arduino Nano and useful for a range of lightweight projects including multi-rotor RC copters. As tiny as it is (the length of a ‘AAA’ battery), the Micro still gives you 20 I/O pins, including 12 analog inputs. Like the Leonardo, the Micro can simulate a USB keyboard or mouse, thanks to Arduino IDE’s keyboard/mouse libraries.

Arduino Mega 2560


The Arduino Mega with its 70 I/O pins powers many open-source 3D printers.

Price: from $17 (eBay)

The key to the Mega is its digital I/O options. It uses Atmel’s ATMEGA2560 controller chip to offer up to 70 I/O pins and is ideal for those complex projects where you need to control multiple devices at once. The Mega is the brains behind many open-source 3D printers (and a few commercial models too). It only has 8KB of RAM and 256KB of flash storage but it’s more than enough to create a full-function 3D printer. It’s amazing what you don’t need when you don’t run bloatware…

Arduino Due


The Arduino Due runs an 84MHz ARM Cortex M3 microcontroller.

Price: from $35 (eBay)

Introduced in late 2012, the Due is the same size as the Mega but is the first Arduino to use an ARM-class microcontroller. It’s based on the ARM Cortex M3 design with 32-bit processing and a clock speed of 84MHz. It features 96KB of RAM and 512KB of flash storage. There are 66 I/O pins (54 digital, 12 analog) and includes two USB ports, one a host port. The Cortex M3 is a basic version of the Cortex A-series chip inside your tablet and smartphone.

Intel Galileo


Price: around $90

The Galileo is set to become the most powerful Arduino-compatible board of them all and marks Intel’s introduction into the Arduino ecosystem. It is fully compatible with the Arduino Uno, but runs Intel’s new Quark X1000 SoC (system on a chip), a 32-bit Pentium-class x86 processor running at 400MHz. It features 512KB of static RAM, 256MB of dynamic RAM and 8MB of on-board flash. But with on-board 10/100 Fast Ethernet, host USB port and a MicroSD card slot, connectivity and storage won’t be a problem. Did we mention the PCI Express mini card slot on the back? Best of all, the Galileo is programmed using the same software as standard Arduino boards.