Recipes for Raspberry Pi
This series of blogposts is intended as a beginners’ introduction to the Raspberry Pi computer.
Raspberry Pi is a credit card sized computer that plugs into a TV set and a keyboard. It is intended as an inexpensive way to allow children to learn about computing and programming. The computers themselves cost around £30, but you will also need a few peripherals to get started, including a keyboard and mouse, TV set, power supply and a SD memory card.
I bought my Raspberry Pi from Farnell/Element 14. It cost just under £30. Due to demand, the mini-computers were in short supply and it took about 2 months for me to receive it after ordering.
I bought a Raspberry Pi for a couple of reasons, first to get a low cost computer that my kids could use for accessing the Internet for their homework, and secondly out of interest in the technology and its uses.
The Pi comes without any additional peripherals or software. The operating system has to be downloaded from the Internet using another computer and loaded onto a compatible SD memory card.
- USB keyboard – £5 (Asda)
- USB mouse – £3 (Asda)
- Power supply with Micro USB connector 5V, 1000mA – £7 (Tiger)
- TV set with HDMI connector – £130 (Tesco)
- HDMI cable – £1 (Poundland)
- SD memory card – £12 (Asda)
It is important that a suitable power supply is used with the Raspberry Pi. A 5 volt 1 amp unit is recommended. I tried a unit that only provided 400 milliamps instead of 1 amp and I found that the mouse didn’t always work and the Pi was prone to crashing.
Having read a few posts on the Raspberry Pi forums I found that several people had experienced compatibility problems with certain high speed SD memory cards. I bought a Sandisk SDHC 8 GB (Class 4) which some people recommended and it has worked without problem. I’ve also tried a 4GB version of the same card, again without problem.
The Pi connects to a monitor or TV with a HDMI connector. You can buy a cheap 1 metre HDMI cable in Poundland. There is also a RCA video output which can be connected to older TV sets and some projectors, however I had some issues with this that I’ll explain in a later post.
The Pi comes as a bare circuit board with no cover, but several are available from different online suppliers ranging from around £5 – £15. As a temporary measure I made a Raspberry Pi case from Lego using some diagrams I found online.
There is a choice of operating systems for the Raspberry Pi, all variants of the open-source operating system called Linux. The operating system can be downloaded and installed on the SD memory card, or it is also possible to buy a memory card with the operating system preinstalled from some suppliers. The recommended operating system is a variant of Debian Linux and is downloaded from the official Raspberry Pi site, but other versions can also be installed depending on what you want to do with your Pi. For example RaspBMC turns a Pi into a media centre that can be used for playing videos and music and for accessing Youtube.
Installing the operating system didn’t prove very easy at first – there are several steps to follow, and the instructions aren’t always clear. This will be the subject of my next post on the Raspberry Pi.