Eben Upton thought a new generation of youngsters might never develop valuable hardware and software hacking skills unless they had access to cheap, hobbyist-friendly computers. So he set out to build one himself. The resulting tiny box, which sells for just $25, has been a big hit. It could boost computer skills not only among children but among adults in poor countries as well.
Upton came up with the idea in 2006, when he was finishing his PhD in computer science at the University of Cambridge. Having agreed to help out with undergraduate computer science admissions, he was looking forward to interacting with teenagers who loved messing around with computers as much as he had when he was younger.
Upton had done all that messing around partly for the thrill of bending the machines to his will, and partly because the 1980s boom in video games had made it easy to imagine making a fortune working with computers. “I was a mercenary child,” he says, sounding a bit apologetic. “One of the things that drew me to computing was that there were 15-year-old kids who made so much money from computing they actually bought Ferraris.”
To judge by the applicants Upton was looking at, however, kids had lost interest. They were still messing around on computers, but they weren’t messing around with them. They weren’t writing programs and taking apart circuit boards. They were the kinds of kids who played World of Warcraft and exchanged cat pictures on Facebook. They had changed from active hackers to passive consumers.
Perhaps the dot-com bust had killed some of the enthusiasm for hacking. But to Upton, one other possible factor loomed large. In the 1980s, he and his friends had learned basic computer science on a BBC Micro, a line of computers built for the British Broadcasting Corporation by Acorn Computers and installed in most English schools. Small, rugged, inexpensive, and expandable, the Micro introduced a generation of British children to hardware engineering and software programming.
There was no contemporary equivalent to the Micro. “Sure, everyone in the middle class has a PC,” Upton says. “But even then, often there is only the one family PC. You won’t let kids screw around with it.” Schools aren’t going to let students take apart their machines, either. As a result, he observes, “computing” classes teach children how to use Microsoft Word and PowerPoint. “Even Microsoft wants schools to produce software engineers,” Upton says. To successfully restore literacy in computer tinkering, he decided, the world needed a modern analogue of the BBC Micro.
Being a hardware guy at heart, Upton went ahead and built a prototype of a next-generation hobbyist machine—the sort of stripped-down device that would enable its users to become acquainted with the guts of a computer. It would also allow its users to put the machine to work in projects ranging from robotics to wearable computing to gaming. He eventually took up a Cambridge professor’s suggestion to call his device Raspberry Pi, tipping his hat to the old tech tradition of naming computers after fruit. But he didn’t immediately see a way to produce Raspberry Pi in sufficient numbers to make a difference, so he reluctantly mothballed the project.
After finishing his PhD, Upton went to work at the Cambridge, U.K., office of Broadcom, a networking company based in Southern California. (He is now one of the company’s technical directors for Europe.) Upton was instrumental in the creation of Broadcom’s first microprocessor intended for multimedia applications—the BCM2835. Released in 2011, it is a single chip that’s small enough to fit in a phone but big enough to contain vital parts such as a central processing unit and a graphics processor. By some measures it was the most powerful chip in the mobile market at the time, and it was a tremendous success for Broadcom.
It was also, Upton realized, the way to restart Raspberry Pi, given that a single-chip computer would be much less costly to produce. He and half a dozen volunteers worked on the new version on evenings and weekends. But the BCM2835 wasn’t easy to deal with: it was dauntingly jammed with tiny components, including no fewer than five power supplies.
To keep Raspberry Pi small and cheap, the team wanted to build it on a single circuit board that could be stamped out, no further assembly required. But to enable the phone chip to work with computer peripherals and run full-scale computer software, they would, it appeared, need to build a board with more than eight stacked layers of circuitry, a prohibitively complex and expensive proposition. Working furiously to simplify the circuitry, the team eventually managed to shave the board design down to six layers.
The first prototypes were ready in December 2011, but Upton discovered, to his horror, that they didn’t work at all. Fighting panic at the thought of all the various subtle flaws that might be buried in all those layers of tangled circuitry, the team discovered that one pin on the chip had been inadvertently disconnected. It was a blessedly easy fix, and within minutes, his invention was popping to life.
The Raspberry Pi is strikingly unlike other computers. About the size of an Altoids box, the computer has no keyboard, monitor, or disk drive—it doesn’t even have an internal clock or an operating system. In other words, the machine requires a fair amount of hardware and software tinkering just to get started. It almost dares you to take it on and try to hack together a robot or gaming system.
It can’t get by on looks. Lacking a case, the Raspberry Pi offers a dense, bristling cluster of tiny electronics to the owner’s view, with five ports: HDMI, to hook the computer up to a television; USB, to hook it to multiple devices; Ethernet, for data; and analog TV and analog stereo. But having to face the guts of the device is a good thing, according to Upton. “Kids can see what they ordinarily can’t see, unless they smash a phone,” he says.
The really surprising feature of the Raspberry Pi is the $25 price: about a tenth the cost of the lowest-priced computers available in stores (if you ignore tablets, which no one can hack anyway).
It was intended for kids, but hackers of all ages wanted it, and so did budding computer scientists in poor countries. Almost the instant the Raspberry Pi went on sale, orders crashed the websites of its two vendors, RS Components and Premier Farnell. The companies reported that they were taking in orders fast enough to tear through the entire initial stock of 10,000 computers in minutes.
Thrilled with the reception, Upton is making more of the devices through a nonprofit Raspberry Pi Foundation he put together—his mercenary tendencies having abated over the years. In fact, he says, he intends to sell two million Raspberry Pis a year in order to reach a critical mass that will support an active community of owners to share tips and applications. He also hopes that the existence of this community will prompt schools to adopt the Raspberry Pi for courses.
Even more important, Upton hopes, is that kids start to take them apart. “That would be real success,” he says.
—Charles C. Mann