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Raspberry Pi

Despite first impressions, the Raspberry Pi is not a tasty snack. The Raspberry Pi is a small, powerful, and inexpensive single board computer developed over several years by the Raspberry Pi Foundation.

If you are a looking for a low cost, small, easy-to-use computer for your next project, or are interested in learning how computers work, then the Raspberry Pi is for you.
Raspberry Pi 3 Model B

The Raspberry Pi was designed as an educational device and was inspired by the success of the BBC Micro for teaching computer programming to a generation. The Raspberry Pi Foundation set out to do the same in today's world, where you don't need to know how to write software to use a computer. At the time of printing, the Raspberry Pi Foundation had shipped over 2.5 million units, and it is safe to say that they have exceeded their expectations!

The Raspberry Pi Foundation

The Raspberry Pi Foundation is a not-for-profit charity and was founded in 2006 by Eben Upton, Rob Mullins, Jack Lang, and Alan Mycroft. The aim of this charity is to promote the study of computer science to a generation that didn't grow up with the BBC Micro or the Commodore 64.

They became concerned about the lack of devices that a hobbyist could use to learn and experiment with. The home computer was often ruled out, as it was so expensive, leaving the hobbyist and children with nothing to develop their skills with.

History of the Raspberry Pi

Any new product goes through many iterations before mass production. In the case of the Raspberry Pi, it all began in 2006 when several concept versions of the Raspberry Pi based on the Atmel 8-bit ATMega664 microcontroller were developed. Another concept based on a USB memory stick with an ARM processor (similar to what is used in the current Raspberry Pi) was created after that. It took six years of hardware development to create the Raspberry Pi that we know and love today!
Official logo of Raspberry Pi

It wasn't until August 2011 when 50 boards of the Alpha version of the Raspberry Pi were built. These boards were slightly larger than the current version to allow the Raspberry Pi Foundation, to debug the device and confirm that it would all work as expected. Twenty-five beta versions of the Raspberry Pi were assembled in December 2011 and auctioned to raise money for the Raspberry Pi Foundation. Only a single small error with these was found and corrected for the first production run.

The first production run consisted of 10,000 boards of Raspberry Pi manufactured overseas in China and Taiwan. Unfortunately, there was a problem with the Ethernet jack on the Raspberry Pi being incorrectly substituted with an incompatible part. This led to some minor shipping delays, but all the Raspberry Pi boards were delivered within weeks of their due date. As a bonus, the foundation was able to upgrade the Model A Raspberry Pi to 256 MB of RAM instead of the 128 MB that was planned. This upgrade in memory size allowed the Raspberry Pi to perform even more amazing tasks, such as real-time image processing.

The Raspberry Pi is now manufactured in the United Kingdom, leading to the creation of many new jobs. The release of the Raspberry Pi was met with great fanfare, and the two original retailers of the Raspberry Pi - Premier Farnell and RS components-sold out of the first batch within minutes.

Not only Eben Upton is the founder of Raspberry Pi. The original founders of the Raspberry Pi Foundation except Eben Upton included:
■ Rob Mullins
■ Jack Lang
■ Alan Mycroft
■ Pete Lomas
■ David Braben

The organisation now consists of two parts:
■ Raspberry Pi (Trading) Ltd. performs engineering and sales, with Eben Upton as CEO.
■ The Raspberry Pi Foundation is the charitable and educational part.

The Raspberry Pi hardware

At the heart of Raspberry Pi is the powerful Broadcom BCM2835 "system on a chip". The BCM2835 is similar to the chip at the heart of almost every smartphone and set top box in the world that uses ARM architecture. The BCM2835 CPU on the Raspberry Pi runs at 700 MHz and its performance is roughly equivalent to a 300 MHz Pentium II computer that was available back in 1999. To put this in perspective, the guidance computer used in the Apollo missions was less powerful than a pocket calculator!!!The Raspberry Pi comes with either 256 MB or 512 MB, or 1GB(on Raspberry Pi 3) of RAM, depending on which model you buy. Hopefully, this will increase in future versions.
Block diagram of Raspberry Pi model B

Graphic capabilities

Graphics in the Raspberry Pi are provided by a BroadCom Videocore 4 3D GPU. The graphic performance of the graphics processing unit (GPU) is roughly equivalent to the Xbox, launched in 2011, which cost many hundreds of dollars. These might seem like very low specifications, but they are enough to play Quake 3 at 1080p and full HD movies.There are two ways to connect a display to the Raspberry Pi. The first is using a composite video cable and the second is using HDMI. The composite output is useful as you are able to use any old TV as a monitor. The HDMI output is recommended however, as it provides superior video quality. A VGA connection is not provided on the Raspberry Pi as it would be cost prohibitive. However, it is possible to use an HDMI to VGA/DVI converter for users who have VGA or DVI monitors.

The Raspberry Pi also supports an LCD touchscreen. An official version has not been released yet, although many unofficial ones are available. The Raspberry Pi Foundation says that they expect to release one this year.

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