Which Raspberry Pi should you buy?

Raspberry Pi B+

Who's it for?

People wanting to use the Pi as a desktop computer or media centre.

What is it?

If you're looking to turn the Pi into a media centre the $35 B+ is probably the right choice. With double the memory of its smaller sibling, you can be confident the B+ will be capable of running future releases of the RaspBMC or OpenElec media streamers. Unlike the A+, the board also includes an Ethernet port. As well as providing another channel to deliver audio and video to the device, Ethernet is also prone to fewer potential network hiccups than wifi.

The B+ may also be the better choice for people wanting to use the Pi as a Linux desktop machine and learn about computers and coding. With four USB ports compared to the A+'s one, it is relatively simple to plug in a keyboard and mouse and start using the B+, without the additional hassle of setting up a USB hub. The B+ 's ports can also power more energy hungry peripherals, such as external hard disk drives and wifi dongles. As with media centre users, having the Ethernet port also makes network connectivity simpler.

Both the A+ and B+ use a "low-noise" power supply that provides a dedicated supply rail for audio and has a dedicated output driver.

The specs

Chip: Broadcom BCM2835 SoC

Core architecture: ARM11

CPU: 700 MHz Low Power ARM1176JZFS Applications Processor

GPU: Dual Core VideoCore IV® Multimedia Co-Processor. Provides Open GL ES 2.0, hardware-accelerated OpenVG, and 1080p30 H.264 high-profile decode. Capable of 1Gpixel/s, 1.5Gtexel/s or 24GFLOPs with texture filtering and DMA infrastructure.

Memory: 512MB SDRAM

Operating System: Boots from Micro SD card, running a version of the Linux operating system. A range of Linux-based OSes are available to download, including NOOBS, Raspbian, Pidora, OpenELEC, RaspBMC. Also available is Risc OS, a non-Linux distro.

Dimensions: 85 x 56 x 17mm

Power: Micro USB socket 5V, 2A

Ethernet: 10/100 BaseT Ethernet socket

Video Output: HDMI (rev 1.3 & 1.4), Composite RCA (PAL and NTSC)

Audio Output: 3.5mm jack, HDMI

USB: 4 x USB 2.0 Connector. Default allowed USB current across 4 ports is 600mA, but can be increased to 1.2A via a config.txt parameter if a good quality 2A PSU (power supply unit) is used.

GPIO: Connector 40-pin 2.54 mm (100 mil) expansion header: 2x20 strip. Providing 27 GPIO pins as well as +3.3 V, +5 V and GND supply lines

Camera: Connector 15-pin MIPI Camera Serial Interface (CSI-2)

JTAG: Not populated

Display Connector: Display Serial Interface (DSI) 15 way flat flex cable connector with two data lanes and a clock lane

Memory Card Slot: SDIO

Raspberry Pi Foundation

Raspberry Pi Compute Module

Who's it for?

People who want to use the Pi inside a commercial appliance.

What is it?

Unlike the Pi boards, the compute module is designed to sit inside appliances.

The board is devoid of the Pi's usual ports, and instead is slimmed down to the size of a memory module found inside a computer.

Designed to be slotted into a printed circuit board the module was made to answer growing demand for using the Pi inside commercial electronics.

"Particularly over the past year, we've seen people starting to use the Raspberry Pi board as a sub-component in what we call an industrial or embedded application - using a Raspberry Pi as part of another product," said Eben Upton, one of the founders of the Raspberry Pi Foundation, at the time of the module's launch.

Upton said the module provides a simple way for people who have prototyped a product on the Pi to build the board into their final release, so they don't have to make significant software changes.

A range of appliances have gone on sale with the compute module inside, such as the Modberry automation controller.

The board reduces the Pi to its essentials - providing the system-on-a-chip, memory and onboard storage. Alongside that, all of the usual processor interfaces are available to whatever hardware you plug into your PCB.

A Compute Module IO board is also available to plug the module into and experiment, ahead of commiting to the expense of creating a custom PCB for the module to sit in.

The specs

Compute Module

DDR2 SODIMM sized 6.5cm by 3cm board

BCM2835 chip with 512MB RAM

On board 4GB eMMC Flash memor

200 pin edge connector

IO board

Multiple GPIO interfaces

1 x micro USB connector type B

1 x USB connector type A

2 x CSI ports for camera boards

2 x DSI ports for display boards

Full size HDMI port

Raspberry Pi Foundation

Kano

Who's it for?

Younger children - under 10's - and the less technically-minded to ease themselves into learning about computing and have fun while doing so.

What is it?

This is the Pi baked to a new recipe, one that is primarily about making using the machine as easy and enjoyable as possible.

Kano is designed to be a colourful, simple and fun toolkit for learning how to control computers.

The board walks users through setting up and learning the basics with colourful illustrated story books, as well as providing a neon-orange keyboard and assorted cables to get started using the Pi immediately.

Coding can be intimidating at first and, rather than unleashing an arcane world of closures and prototype chains, Kano eases children in with its own operating system and various easy to use tools. Kano Blocks is a visual programming language that allows children to build and alter software by connecting blocks. The program outputs working games alongside the JavaScript and Python code they are built with.

Also loaded on the Kano is the drag and drop programming software Scratch, Codeacademy and Hacking Fundamentals, which provides an introduction to a popular Linux shell. Last but not least is Minecraft, a game that allows such freedom for creativity that 8-bit CPUs have been built in its world.

To help children at school, Kano provides exercises and tools for each key stage in the new UK computing curriculum.

Eben Upton, co-creator of the Raspberry Pi, has praised the Kano for making the machine more accessible to younger and less technical audiences.

The specs

£99 pack

Kano Books, illustrated and intuitive

Kano OS and levels on 8GB SD card

DIY speaker

Raspberry Pi Model B

Kano Keyboard Combo

Custom case

Card mods and stencils

Stickers

Cables: HDMI*, Mini-USB

Smart power plug (all region pins available)

Wifi powerup

Kano

BrickPi

Who's it for?

Those interested in controlling robots using the Pi but who want some help getting started.

What is it?

This kit is designed to make it simpler to use the Pi to control robots built from Lego.

The BrickPi is a board that slides over the Raspberry Pi and allows it to connect to and control Lego Mindstorm motors and sensors. Bots, or more accurately the bot's sensors and motors, are programmable using Python. The board also includes a 9V battery to power the Pi and the bot.

The BrickPi allows you to connect up to four motors and five sensors, and has editable firmware for its microcontroller. Both the hardware designs for the board and its software source code are also available online.

The specs

The $140 Brick Pi starter bundle includes:

BrickPi Advanced Power module

BrickPi Acrylic Case

BrickPi Power Pack

SD Card with Raspbian Installed

Wifi Dongle

Raspberry Pi Model B

The board:

Clock: The microprocessor is run on a 16MHZ clock.

Serial Line: The serial line runs from the Raspberry Pi to the two Arduino chips.

Power: Power is supplied to the entire unit with a 9 – 12V battery. The power source supplies drive power to the motors directly. The power source is regulated to 5V depending on the model: Advanced power uses a step down regulator, and the basic model uses a switching device voltage regulator. The 5V rail supplies power to the BrickPi microcontroller, Raspberry Pi, sensor ports, and indicator LEDs.

Motors: Motors are controlled by the Texas Instruments SN754410. PWM control is supplied by the Arduino, and power is provided directly by the 9V battery.

Sensors: Sensors are powered off the 5V regulator. These can be normal digital sensors or analog sensors. These sensors are read by the micro controller.

Ports: All Ports (sensor and motor) are the Dexter Industries NXT Sockets for LEGO MINDSTORMS NXT.

Pi-Top

Who's it for?

Those who want a Raspberry Pi they can use on the move

What is it?

This Pi-Top is a Raspberry Pi laptop, or at least all of the parts you need to build a Raspberry Pi laptop, including the case. The computer can be put together in "an evening", according to its designers, and can be assembled without any soldering.

The machine is available in a variety of configurations, including the option to print out the case yourself using a 3D printer, or without the Raspberry Pi, for those who already own the board.

The Pi can easily be clipped and unclipped from inside the laptop. Also available add-on boards called HATs that slot onto the Pi and provide the connectivity, sensors and other electronics to make it easier to use to control robots, set up home automation or to drive higher resolution screens.

The project has raised about $140,000 through the Crowd Funding website Indiegogo and the first machines are expected to ship next May.

The specs

$239 kit ($269 with the Raspberry Pi B+)

Injection molded case

3D printer STL files compatible for most print bed sizes (5" x 5" bed size and up)

PCBs - Power Management, HDMI to LVDS Bridge and Keyboard & Trackpad Controller.

Electronics breadboard

Battery

Keyboard

Trackpad

13.3”HD LCD Screen

Wifi adapter

Acrylic slice

Wiring

DC wall plug

Build instructions

Online & integrated lesson plans

Pi-Top