Thursday, 10 March 2016

Raspberry Pi 3: Fancy A Fresh Slice Of Pi?

David Crookes cuts into the latest Raspberry Pi and licks his lips in anticipation...

In February 2015, the Raspberry Pi Foundation believed it had a record breaker on its hands. An impressive five million Raspberry Pis had been sold in total, which just edged it above the ZX Spectrum and led to early claims that it had become the biggest-selling British computer of all time. Then someone mentioned the Amstrad PCW range had sold eight million and was also very much British, and it caused a bit of backtracking.

Fast forward a year to 29th February 2016, though, and not only was the Raspberry Pi celebrating its fourth birthday, but it was also announcing that it, too, had sold eight million units. It was a staggering figure, which pointed to three million sales in just 12 months. “We’re calling it,” said foundation co-founder Eben Upton. “We’re the best-selling UK computer ever.”

Some companies would perhaps celebrate this amazing feat with a bottle of bubbly and a slice of cake, and perhaps that’s what the Raspberry Pi Foundation team did (deservedly so). But they also went one further and gave everyone a present of sorts. They announced the Raspberry Pi 3 – a brand new version of the bare-bones computer that has shaken and rattled the industry, the hobby market and the approach to teaching ICT. We wouldn’t be surprised if it has increased the total sales to 10 million before the year is out.

As if to underline just how important the Raspberry Pi has become, the announcement of the £30 computer was immediately seized on not just by the specialist press but mainstream newspapers and magazines too (the Mirror called it “world-changing”, which, in some sense, has a grain of truth in it). This is the machine that has been sent to the International Space Station along with astronaut Tim Peake, and it’s the mini-marvel that has opened up coding to a whole new generation. Small it may be, but its impact has been undeniably huge.

For those who are unaware, the Raspberry Pi 3 Model B is the latest release of the most pioneering range of bare-bone computers around today. It comes without any protective casing nor any leads, but it can be connected to a computer monitor or television and make use of a standard keyboard and mouse. As well as deliberately keeping the manufacturing costs low, the “nakedness” of the computer invites exploration and creative thinking. It shows the components that make up a computer, and it encourages experimentation.

At the same time, it evokes the ethos of the home computers of the 1980s. Just as those retro machines had a blinking prompt just waiting for you to tap in a quick 10 PRINT “Steve smells” 20 GOTO 10 in Dixons to much mirth, the Pi has also looked to make it easy for people to start programming from the very start. Even so, it can be used for other desktop computing tasks, and there’s a web browser to hand and lots of games available. You could use it as a work computer, but that would be criminal given there’s so much else it can do.

Given this background, the Raspberry Pi 3 Model B demands a look, but what does it bring to the table? Well, it has a faster 64-bit processor and a built-in wi-fi connection, but it’s the latter which excites the Pi team the most. Upton talks about it being a “big step” for the computer. Over the small number of years of the Pi’s existence, this has had a fair few people gnashing their teeth in frustration, because they’ve had to look around for the ‘missing’ element. In truth, it’s a convenient step but perhaps not killer enough for jaws to drop.

Still, although the need to connect an external antenna was something of a learning process – an achievement for newbies to ‘unlock’, if you will – having it firmly on board from the off is a step in the right direction. The connectivity is provided in the guise of a built-in Broadcom BCM43438 chip that allows for 2.4GHz 802.11n wireless LAN. It eliminates the need for wired Ethernet, USB wi-fi adapters or Ethernet-towireless gadgets, and it should make the computer even more accessible to users.

On top of that, the Broadcom chip has built-in Bluetooth Low Energy and Bluetooth 4.1 Classic radio support, which means users can connect up a wireless keyboard or mouse out of the box while allowing the computer to communicate with a host of other devices. “This is the first Pi you can stick behind your TV and completely forget about,” Upton has said (it can be plugged directly into a USB port and draw power). It will certainly be a boon for anyone looking to put the computer at the heart of an Internet of Things smart-home given, that it will be able to talk to all manner of gadgets.

The other major difference between the Pi 3 and its predecessor is the freshly made Broadcom BCM2837 system-on-chip (SoC). Upton says it retains the same basic architecture as its predecessors, BCM2835 and BCM2836, and he points out that this means it will work with all the existing tutorials and projects that had proliferated around this machine. But there are some major advances.

The new Pi has a 1.2GHz 64-bit quad-core ARM Cortex-A54 CPU, which is ten times faster than the original Pi (it’s up to 60% faster than the Pi 2). It has 32KB Level 1 and 512KB Level 2 cache memory as well as a VideoCore IV graphics processor. The SoCalso also links to a 1GB LPDDR2 memory module to the rear of the board.

In all other respects, though, the Raspberry Pi 3 is very much the same as the Raspberry Pi 2 (save for the moving of the LEDs). It’s less a revolutionary leap, more a few steps forward, and yet it does consolidate the computer’s capabilities. Upton appears very much aware of this, and he’s suggested the new Pi is looking to make life easier for the current users of the device. He has said that people tend to use it as a replacement for a PC or as an embedded computer. “The Pi 3 is doubling down,” he says, as opposed to the team looking to expand the capabilities and figure out new markets and uses for it.

What that means is the Raspberry Pi 3 has, like the Pi 2 before it, four USB ports, a full HDMI port, 40 GPIO pins, an Ethernet port, a camera interface and combined 3.5mm audio jack and composite video. It has a display interface and a micro-SD card slot that is now push-pull instead of the previous push-push. It won’t mean the end of the Raspberry Pi 1 Model B+ or the Raspberry Pi 2 Model B, though. Both are remaining on sale (for as little as £21.59 and £29.40 respectively). And it doesn’t mean you can’t snap up the cut-down original Pi Model A+ for £18.60 (a Pi 3 Model A+ is said to be coming soon). The slices of Pi have just become more plentiful.

Educating The Masses

What are the wider consequences of this new computer? That may seem an odd question, but the Raspberry Pi has always been more than a machine. It’s underpinned by a mammoth educational, charitable organisation with a huge drive to promote computer science. It has 60 full-time employees, its own official magazine and training programmes for teachers. There’s a £1 million education fund, which has been running for a couple of years, looking for projects that benefit children aged between five and 18. It seeks projects that make use of computing technology either in and of itself or within STEM subjects and the creative arts.

Asking how the Raspberry Pi 3 will affect education is therefore valid, and the answer is that the computer will provide a pleasant boost. Producing new computers such as the Raspberry Pi 3 and the Raspberry Pi Zero – as inexpensive as they are – help to generate a small profit that can be used in such enterprises. A new release keeps the interest peaking and, as the £4 Zero in particular proved, has the potential of catching the eye to such a degree that it can become big, global news.

This is one of the major reasons why, regardless of the lack of an amazing shift forward, you should seriously consider an upgrade. The more the Pi sells, the more chance there is of educating greater numbers of teachers and pupils. In that sense, buying a Pi 3 is an investment in our children’s future as much as in a piece of hardware for yourself. It’s all very much win-win: users get powerful, small computers that they can use to stretch their minds and understanding, and the foundation  gets the money it needs to keep push the learning aspect of its remit.

At the same time, there is an inherent danger in constantly moving forward. As the Raspberry Pi becomes more powerful, it becomes vital that teachers are able to keep up. It’s already been a long process to get to this point, and no one wants to risk derailing the process so early on.

To explain, when it was announced in the UK that the ICT curriculum was being torn up and replaced by a computing subject, it scared a good number of teachers. They were used to showing children how to use the tools that had been created by others but not so hot on how those apps were developed in the first place.

There was also a great deal of anxiety that their pupils may well know more than them, but the Raspberry Pi Foundation was able to step in at the right time and not only bring educators up to speed but show that fostering an environment of mutual learning in the classroom could be widely beneficial to all sides.

Over the years, Picademy has runs dozens of workshops for teachers and suggested projects they can try. There has been a strong tie-up with Code Club and an emphasis on what the Pi Foundation refers to as the “maker approach”. These kinds of programmes are important if teachers are going to be able to continue their work, but the key is for the Pi Foundation to keep the education and the roll-out of new machines in step – something that requires ongoing funding and effort.

If the Raspberry Pi becomes too advanced, some retraining of those who have already gone through the process may be necessary. There is also a risk of making the machines appear too complex. There could well be a line that the Pi crosses at some stage in the future, which starts to move the computer further and further away from its core aims without being able to bring teachers up to speed in time. That time hasn’t come yet, though.

Well Intentioned?

Is the greater good really a reason to spend 30 notes on a new computer? To some degree, yes. In an interview with a leading gadget magazine, Upton said the UK government had declined to provide funds for the Raspberry Pi project a couple of years before it was launched, which is a pity. It appears the government believed there was no market for the computer, and the door to that particular revenue stream appears to have been closed ever since. There’s still a technology skills shortage, and computers such as the Raspberry Pi 3 help to form bridges over the gaps and foster learning among the young. If that’s not a reason to buy, we don’t know what is.

Of course, the more money that’s invested, the greater chance of the Pi being enhanced in the future. Upton has already said that features will be added to the Pi if they can be done so without affecting the overall cost of the product, and some of those wouldn’t pose a problem to learning. A switch to USB 3.0 would not perplex youngsters or teachers, for instance, and neither would the addition of extra RAM.

For now, though, the Raspberry Pi 3 continues to allow people to delve deep into their machines. It’s a computer that shows how the processes work and how coding can achieve all sorts of weird and wonderful outcomes. Some people have suggested making the Pi powerful enough now for a fullblown Windows 10 to be installed, but that’s going back to the initial problem of creating computers for consumers and not developers. While that could be good for people who are simply after a cheap workhorse, it’s not really what the foundation founders were thinking ten years ago.

So yes, buy a Raspberry Pi 3 and enjoy the extra benefits it brings. Use it to produce projects that equal or better those we looked at a few issues ago. The Raspberry Pi 3 delivers two things that people have wanted for a long time – speed and connectivity – without going crazy and adding any perplexing technologies. It tastes as good now as it always has.

Raspberry Pi 3 Specs

SoC: Broadcom BCM2837
CPU: 4× ARM Cortex-A53, 1.2GHz
GPU: Broadcom VideoCore IV
RAM: 1GB LPDDR2 (900MHz)
Networking: 10/100 Ethernet, 2.4GHz 802.11n wireless
Bluetooth: Bluetooth 4.1 Classic, Bluetooth Low Energy
Storage: Micro-SD
GPIO: 40-pin header, populated
Ports: HDMI, 3.5mm analogue audio-video jack, 4× USB 2.0, Ethernet, Camera Serial Interface (CSI), Display Serial Interface (DSI)


Eben Upton wears two hats: he’s a technical director and ASIC architect for Broadcom, and he also co-founded the Raspberry Pi Foundation in 2009. As CEO of Raspberry Pi Trading, too, it makes him a very busy man, but he took time out to answer our questions.

What possibilities does the Raspberry Pi 3 now bring to the Pi community?

EU: There are three things. The Raspberry Pi 3 brings more CPU performance, which makes the device a much more credible PC replacement. Wireless LAN and Bluetooth also mean that in the PC-replacement role you can be almost completely wireless (you only need a power and HDMI cable). Finally, wireless LAN and Bluetooth allow us to act as an ‘IoT hub’, aggregating the output of numerous lowcost sensors and uploading the data to the cloud.

Which features of the Raspberry Pi 3 do you consider most crucial, and why have they only become viable now?

EU: The wireless features are the real headline in this generation. They’ve become viable due to incremental reductions in component and manufacturing costs, and because we now have a large enough engineering team at Raspberry Pi to take on the burden of wireless design and conformance testing.

What are your hopes for the Pi at this stage?

EU: Our dream was originally to get back to the level of involvement in computing that we saw in the 1980s, but since then we’ve become more ambitious. You have to remember that only a very small, privileged, segment of the population had access to a high-quality computing and engineering education then. The opportunity is to go beyond that to the point where all young people, in the UK and overseas, have the opportunity to become engineers.

What would you like to see in a Pi 4?

EU: I’d prefer not to speculate at this stage, other than to say that of course we’d want faster CPU cores!

How well is the Raspberry Pi Zero doing and has it exceeded expectations?

EU: It’s doing well. I think we underestimated the level of demand. We’re ramping up production nicely now (subject to the constraints imposed by building lots of Raspberry Pi 3 units at Sony in Wales), and hope to catch up with demand in the next couple of months.

Ingredients For A Pi

The idea for the Raspberry Pi was formed almost exactly ten years ago when Eben Upton, a lecturer at Cambridge University, was finishing his PhD and realised that the A-level students he had been asked to interview for the Computer Science degree were severely lacking the level of knowledge of their predecessors.

He realised that a generation of children were dropping down an educational hole in terms of computing and he felt that most teaching of IT tended to revolve around familiarising students with Microsoft Word and Excel rather than programming. This approach, combined with the fact that the glossy front-ends of computers had persuaded people not to tinker ‘under the hood’, got him thinking.

Having been brought up hacking and programming on his BBC Micro, he felt that making a similar system available for children today would be hugely beneficial. As luck would have it, he wasn’t the only person thinking of solutions to the same problem. His friend Jack Lange, a demonstrator at Cambridge University’s Computer Laboratory, also noted the problem, and David Braben, the joint coder of the space trading game Elite, was rocked by children who found ICT to be the most boring subject at school. Computer science applications were substantially dropping even though the university population was rising. Something, they all surmised, needed to be done.

Initially, they considered producing a software platform; they also thought about snapping up lots of retro computers and flooding schools with as many as they could find. But neither were seen as ideal, and the latter, in particular, would have led to the secondary problem of having to share computers. It would be natural for a select few to start hogging the machines and leaving others behind. The solution was to produce an inexpensive bare-bones machine that could potentially be handed to every child.

Upton began to crack on. He produced a few prototypes, his first an Atmel Atmega644 microcontroller-based platform that ran at 22.1MHz and had 512K SRAM for data and framebuffer storage. Colleagues Rob Mullins, Alan Mycroft and Lang helped, Braben got on board, and they touched base with Pete Lomas, who was the managing director of hardware design at Norcott Technologies. In 2008, a charity that became the Raspberry Pi Foundation was formed to promote basic computer science in schools.

The fact Upton began working for Broadcom went in the group’s favour, because they were able to get a good supply of cheap chips. They used Broadcom’s system-on-a-chip, which is designed for phones, but as much as the hardware was important for encouraging children to be curious and inquisitive, the software had to be right too. They went for an open source OS – Linux – which also cut costs, and they encouraged programming in Python and Scratch.

With the hardware and software coming along, they visited the BBC and tried to persuade the Corporation to put its name to the machine. Technology correspondent Rory Cellan-Jones was rather taken by it and made a video with David Braben holding the computer, which went viral. The BBC didn’t lend its name to the machine in the end, but the publicity was enough to reaffirm the Raspberry Pi Foundation’s conviction. Two models were worked on: Model A and Model B with their varying RAM, USB ports and Ethernet (or not).

The Raspberry Pi was launched on 29th February 2012, and the first production batch of 10,000 units sold out within hours. It led to massive delays and caused a lot of stress, but it also helped to increase the hype and publicity around the machine. Since then, schools and hobbyists have taken the Pi to their hearts and there have been two further major iterations, together with a small-form Raspberry Pi Zero. Everyone, it seems, has wanted a slice of the action.