Raspberry Pi 4
|Size||85.6 x 56mm||68.6 x 53.4mm||86.4 x 53.3mm||68.6 x 53.4mm||50 x 20.6mm|
|Processor||64-bit Cortex A-72 quad-core||ATmega328||ARM Cortex-A8 processor||ATmega328||ARM Cortex M4F 6 core|
|Number of Cores||4||1||1||1||6|
|RAM||1GB, 2GB or 4GB||2KB||512MB||2KB||1.5MB|
|Input Voltage||5V||7-12V||5V||7-12V||3.3V or 5V|
|GNSS||Shield/Add on||Shield/Add on||Shield/Add on||Shield/Add on||Integrated GPS & GLONASS|
|Time||NTP||Shield/Add on||Shield/Add on||Shield/Add on||Integrated RTC|
|Digital GPIO||40||14||65||14||6 (GPIO, SPI, I2C, PWM, UART, 1S2)|
|Analog Input||3.5mm AV jack||6||7||6||2|
|Ethernet||1||Shield/Add on||1||Shield/Add on||Shield/Add on|
|USB||2 x USB 3.0, 2 x USB 2.0||1 x USB 2.0||1 x micro USB 2.0||1 x USB 2.0||1 x USB 2.0|
|Video Out||2 x micro HDMI||N/A||No HDMI port (supports BBG HDMI Cape)||N/A||N/A|
|Audio Output||HDMI or 3.5mm jack||N/A||No (supports BBG HDMI Cape or USB audio sound card)||N/A||Hi-res audio output & multi-mic inputs|
|Operating System||Linux, Raspbian, Android, Windows 10, Ubuntu MATE 15.04, OpenElec, Pidora, RISC OS, Snappy Ubuntu Core||Arduino Bootloader||Linux, Neutrino, Integrity, Windows Embedded CE, VXWorks, Android, FreeBSD||Arduino Bootloader||NuttX|
|Bluetooth||Yes||Shield/Add on||Shield/Add on||Shield/Add on||Shield/Add on|
|Wi-Fi||Yes||Shield/Add on||Shield/Add on||Shield/Add on||Shield/Add on|
*Table viewed best on a larger screen.
There are now so many open source programming platforms and single board PCs available that for the beginner it can be hard to know which to choose. Everyone has heard of the Raspberry Pi, but is it right for you? What about Arduino, Orangepip or BeagleBone? Depending on what you want to achieve with your board, to prototype or design a project for the Internet of Things, to play games or run programs, you will want to know how the most popular platforms match up against each other.
Launched in February 2012, the Raspberry Pi was marketed as an educational tool, designed to introduce children to coding and computer circuits. But programmers, makers, hackers and hobbyists grasped the huge potential of the Pi. To date it has shipped 8 million units. The original Pi had a single core processor with 256 MB of RAM, a single USB port and no Ethernet connection. The Raspberry Pi 4, released in 2019, is almost unrecognisable (apart from its footprint, which has barely changed): its quad core 64Bit processor includes 4GB of RAM, boasts four USB ports, two micro HDMI ports supporting dual display and built-in Wi-Fi and Bluetooth.
What distinguishes the Raspberry Pi is the fact that it is a computer – plug it into a monitor, use the USB ports for keyboard, mouse and other shields, run desktop applications, connect to the web and play HD video. The Pi can be programmed via a number of languages such as Python and Scratch.
It is difficult to overestimate the impact the Raspberry Pi has had on education, computing, science and electronics. From time-lapse photography to home industry, movie viewing to music streaming, it has become the device of choice to power IoT projects. A global user community share projects and code, while Tim Peake took two specially modified Pi's onto the International Space Station, where they will remain until 2022. Right now, somewhere in the world, a Raspberry Jam event is probably taking place.
Sitting comfortably in the palm of the hand, the Arduino Uno is the smallest of the boards. Since its launch in 2010 it has not changed in design, features or functionality – but that does not mean it has stayed the same. Every new application expands the Uno's potential. Unlike the Raspberry Pi the Arduino family is comprised of a range of different boards, such as the Leonardo, the Due and the Mega. The Uno remains one of the most popular because of its versatility and ease with which the microcontroller on which it is based, the Atmel ATmega328, can be programmed. If you are an electronics novice the Arduino is your ideal launch pad for home automation projects.
As a microcontroller – rather than a computer – it does not require the power of the Raspberry Pi or BeagleBone. Once your application has loaded you can just plug the Arduino in to your PC via USB; no need to reboot, plug in a keyboard or choose an application to run. The bespoke programming language of the Arduino IDE programming environment is easy to follow and the Arduino can be connected to an almost infinite number of input, outputs and controllers. The Arduino Uno can also work with a wider range of input voltages. It does the job it has been programmed to do, and does it immediately.
Sprinkle some Seeed on the BeagleBone Black and what do you get? The BeagleBone Green.
The BeagleBone Green is a unique collaboration between the open source board and sensor makers Seeed Studio and the BeagleBoard organisation. Seeed has adapted the architecture of the BeagleBone Black, the signature BeagleBone board, retaining most of the components and connectors that makes the Black so popular with prototypers – principally the 92 GPIOs with 65 possible digital input and output pins and 1GHz ARM Cortex-A8 processor. The major difference is that the HDMI port has been replaced by two Grove connectors, giving the BeagleBone Green access to Seeed's extensive family of modular Grove sensors. Grove is a building block system enabling the creation of simple IoT projects, with the focus on environmental sensing.
The interfacing potential of the BeagleBone Green means it scores highly as a prototyping tool – especially for those lacking electronics experience. Most Grove projects can be completed without the need for soldering. If your next hardware project calls for a device to perform sophisticated functions and interact with its environment, as well as connect easily to a network, the BeagleBone Green could be the board for you. BeagleBone Green also has the advantage of being compatible with all BeagleBone Black ‘capes' – the shields or break-out boards made by third parties for functions like display, motor control, prototyping and power supply.
The Orangepip Kona328 is the newest kid on the block. It is very similar to the Arduino Uno – using the same ATmega328 microcontroller and programmable via the Arduino IDE environment. In fact, all you can do with an Arduino Uno you can do with the Orangepip – but for bulk buyers, class packs of the Orangepip could save you nearly 50% on the price of the Arduino Uno.
The board features 14x digital I/O pins, 6 analog outputs, a 16MHz crystal oscillator, 1x USB connection, power jack and ICSP header. The Kona328 contains everything needed to support the microcontroller; simple to use, it requires a USB connection to a computer, AC-DC adaptor or battery to get started. The high performance ATmega 8-bit AVR RISC-based microcontroller provides enough power and memory to store and run multiple lines of code.
Orangepip offers a colourful introduction to coding and prototyping. Use it for game design, environmental sensing and all kinds of home automation projects – such as plant watering indication systems, voice-activated lighting controllers, weather stations and burglar alarms. In fact, a little bit of code goes a long way with the Orangepip. The Kona328 is also compatible with most of the Arduino shields designed for the Uno. If you are new to prototyping, the Orangepip represents the best value board on the market. All you need to add in order to complete simple projects is a USB cable, breadboard, basic components and jumper wires.
Sony's first development board has certainly been worth waiting for.
Despite having less than half the footprint of an Arduino or Raspberry Pi, the Sony Spresense has a considerable number of unique features that sets it apart from other development boards – so, for example, the Spresense features on-board GNSS, a GPS receiver that IoT developers will most appreciate, as well as audio codecs giving high performance audio output. The board also features a real time clock, on board flash memory, and low power consumption – in itself quite impressive considering that the Spresense is based on Sony’s 6 core CXD5602 MCU, generating a clock speed of 156 MHz.
The Spresense is supported by an extension board which adds significantly to its connectivity. This gives compatibility with selected Arduino shields; in fact the board has been designed with Arduino developers in mind. It can be programmed in Arduino IDE, as well as its own NuttX-based OS. A camera module is also available. Developers will be able to use the Spresense to create IoT solutions utilising the board’s key features, from drones to smart speakers and time-lapse cameras.