| Fact: Raspberry Pi devices are sold as Model A and Model B. These are cultural references to the original models of the BBC Microcomputer. |
Functioning on a credit-card sized board, it is a bare-bones PC to which you can connect a TV, keyboard and mouse, and on which you will be able to surf the Web, play Full-HD movies and do almost anything you would want to on a "normal PC" - provided you have the initiative and patience to make it work.
An electronics enthusiast or hobbyist or even a student can easily make use of this computer to build a lot of things: Linux Desktop, Gaming Device, Home Media Center, the list goes on. As more of these boards are shipped out, you can hope to see an even greater variety of uses and functions being executed by the Raspberry Pi computer. And since all the code is open source, it makes it so much easier on the pocket.
The Tech behind it
The Raspberry Pi will run Linux kernel-based operating systems like Debian GNU/Linux, Fedora, Arch Linux, etc. Iceweasel, Calligra Suite, and Python are planned to be bundled with the Raspberry Pi.
Perhaps the most important thing that differentiates the Raspberry Pi is its computing power. This 25$ Single Board Computer (SBC) has as much oomph as the original XBOX did--demos showed the Raspberry Pi handling Quake 3 at 1080p. Now Quake 3 is a game that made even my Intel P3 choke back in 2000.
The Raspberry Pi runs on a 700Mhz ARM11 CPU supported by a Broadcom VideoCore IV GPU. This SBC has a total of 256MB SDRAM which it generously shared with the GPU. The board is powered by a 5 volt microUSB or GPIO header and consumes between 500mA (2.5W) and 700mA (3.5W) depending on the models. The SoC that hosts the CPU, GPU, DSP and SDRAM is from Broadcom (BCM2835).
Another thing to note about the Raspberry Pi is that it does not come with a real-time clock, so an OS must use a network time server, or ask the user for time information at boot time to get access to time and date info for file time and date stamping. However, a real time clock (such as the DS1307) with battery backup can be easily added via the I2C interface.
Arduino vs Raspberry Pi
Starting from the radically different naming schemes--masculine Italian name vs sweet fruit pie--both these boards are significantly different in a lot of things. For one, the Arduino is an open source single board microcontroller while the Raspberry Pi is a single board computer. Ask any electronics enthusiast and he will tell you why it is always better to take the Arduino if this is your first time dabbling with electronics. On the other hand, if you have already dipped your toes in this field you could go ahead for the Raspberry Pi. Below you can find a chart that compares the two boards. It should help you make a good decision if you are new to this field.
| Arduino | Raspberry Pi |
| Extremely easy to get working | Less easier to get working |
| A typical embedded system with easy-to-develop software | Complete computer running Linux |
| Support is available almost everywhere | Support is currently limited but should increase over time |
| More suitable for controlling hardware (robotics) | Features an extremely powerful GPU and can handle hi-def content |
| Umpteen different kits are available | Very few kits are available now |
| Low power consumption, capable of even microamps with very low clock | Comparatively higher power consumption that the Arduino |
| Verdict: While the Raspberry Pi is a great high performance option, the Arduino is a good general use board | |
Different Models
There are 2 models of Raspberry Pi currently featured at the foundation. The Model A is the base model that comes with a lower power profile and is less expensive.
The Model B is slightly more expensive and fully featured. It features an Ethernet port along with 2 USB ports in addition to all the features on Model A.
| | Model A | Model B |
| Price | $25 | $35 |
| SoC | Broadcom BCM2835 (CPU, GPU, DSP, SDRAM) | |
| CPU | 700 Mhz ARM11 Family | |
| GPU | Broadcom VideoCore IV 256MB(Shared) | |
| Memory | 256 MB SDRAM | |
| USB 2.0 Ports | 1 | 2 |
| Video Output | Composite RCA, HDMI | |
| Audio Output | 3.5mm Jack, HDMI | |
| Onboard Storage | SD/MMC/SDIO card slot | |
| Network | None | 10/100 Ethernet (RJ45) |
| Power Rating | 500 mA(2.5W) | 700mA (3.5W) |
Model B was launched first because the Raspberry Pi foundation saw a larger demand for those models.
Launch Plan
The first launch of Model Bs is aimed at software and hardware enthusiasts, makers, teachers and others who want to build exciting things with the Raspberry Pi before the official educational launch, which will happen later in 2012.
They have done this phased launch to ensure that when the Raspberry Pi is launched for the educational market there will already be a community of experienced people in place who would provide support for the newbies. This will also ensure that more mature software will be available for children to use.
