The $5 Pi Zero computer from Raspberry Pi. Credit: RASPBERRY PI FOUNDATION

A chance encounter with Alphabet Inc.’s Google chairman Eric Schmidt in January 2013 led the head of a British nonprofit that makes bare-necessities computers to ditch his plans for a more expensive version of its popular $35 computer, the Raspberry Pi. The Cambridge, U.K.-based Raspberry Pi Foundation had received a $1 million grant from Google to distribute 15,000 units of the build-it-yourself, programmable Raspberry Pi computers to schoolchildren.

At an event announcing the donation—Schmidt happened to be in the U.K. at the time—the Google chairman wanted to know what the foundation was working on next.

“I told him we were thinking of making future Raspberry Pi’s a little bit more expensive, up at about $50 or $60, and a bit more powerful,” Eben Upton, the foundation’s founder, told The Wall Street Journal in an interview.

Eric Schmidt, chairman of Alphabet Inc.’s Google.
Bloomberg News

Mr. Schmidt, says Mr. Upton, said that was the wrong thing to do, and told the foundation’s founder he should aim for as low cost a computer as possible.

“He said it was very hard to compete with cheap. He made a very compelling case. It was a life-changing conversation,” Mr. Upton said, adding that he went back to the lab and scrapped all the engineering plans for more expensive versions of future Pi computers. “The idea was to make a more powerful thing at the same price, and then make a cheaper thing with the same power.”

In the beginning of 2015, the foundation started shipping its new, more powerful Raspberry Pi 2 computer, for the same $35 price as the Pi 1.

And on Thursday, just under three years since the conversation with Schmidt, Upton’s group released its cheapest product yet: a $5 computer called Pi Zero.

The Zero isn’t a complete computer. It consists of a 5 mm-deep circuit board and runs on a Broadcom microprocessor at 1 GHz. It has 512MB of onboard RAM, the same amount of memory that an iPhone 4S has. Sockets allow a user to plug in a keyboard, mouse and monitor. It also has a USB data port and sockets for power, video, and a Wi-Fi dongle. It has a general purpose input/output bar with 40 pins, so users can solder wires onto the pins that are connected to any type of external hardware, like sensors, or even another computer, to send and receive data. It runs on a free version of the Linux operating system, Raspbian, which when installed opens a Windows-style graphic interface with a basic desktop and menu, with access to programs and settings. It can also be used in Internet of Things applications—like controlling garage doors, for instance—as long as they run on the Linux IOT operating system.

Ten thousand units of the device, about the size of a money clip, were being given away free in the U.K., packaged up with the December issue of The MagPie, Raspberry Pi’s magazine, which hit newsstands Thursday.

The other 20,000 units produced by Sony Corp. in a factory in south Wales were all sold out Thursday by distributors in the U.K. and the U.S. Orders were flooding in, Mr. Upton said. He wouldn’t say how much each unit costs to make, but added, “I’m not expecting to lose money on it.”

When up and running, the computer can be used to play games, such as Minecraft and Scratch, a coding tutorial program. It can also be used for many other basic processing purposes, including operating as music players and running robots, as well as having home automation uses, and even for sending tweets from space.

The Pi 1, on sale since February 2012, has sold about 4.5 million units in total.

The Pi 2 has sold between 2.5 million to 3 million units since February, with 250,000 sold in October alone. “There is acceleration, this year has been very big for us,” Mr. Upton said.

The Pi Zero is also rolling out in the U.S. on Thursday for $5. It is available at electronics-learning website Adafruit. Micro Center is also stocking it, and it is being offered on Raspberry Pi’s own website.

In the U.K., it lists for £3.99, or about $6.

“We really don’t think we’ll get any cheaper than this. We’ve gone from say, four lattes, to one latte. We’re not going to go below the cost of one latte,” Mr. Upton said.

Mr. Upton said Mr. Schmidt hasn’t seen the Pi Zero yet. “I don’t want to bother him.”


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