Raspberry Pi is a series of small single-board computers developed in the United Kingdom by the Raspberry Pi Foundation to promote teaching of basic computer science in schools and in developing countries. The original model became far more popular than anticipated, selling outside its target market for uses such as robotics. It does not include peripherals (such as keyboards and mice) and cases. However, some accessories have been included in several official and unofficial bundles. The organisation behind the Raspberry Pi consists of two arms. The first two models were developed by the Raspberry Pi Foundation. After the Pi Model B was released, the Foundation set up Raspberry Pi Trading, with Eben Upton as CEO, to develop the third model, the B+. Raspberry Pi Trading is responsible for developing the technology while the Foundation is an educational charity to promote the teaching of basic computer science in schools and in developing countries.
According to the Raspberry Pi Foundation, more than 5 million Raspberry Pis were sold by February 2015, making it the best-selling British computer. By November 2016 they had sold 11 million units, and 12.5m by March 2017, making it the third best-selling "general purpose computer". In July 2017, sales reached nearly 15 million. In March 2018, sales reached 19 million. Most Pis are made in a Sony factory in Pencoed, Wales. some are made in China or Japan.
All models feature a Broadcom SoC consisting if ARM compatible CPU with on-chip GPU, the VideoCore IV. CPU speed ranges from 700 MHz to 1.2 GHz for the Pi 3 and on board memory range from 256 MB to 1 GB RAM. SD cards are used to store the operating systems. Most boards have between one and four USB slots, HDMI composite video output and a 3.5 mm audio jack. Lower level output is provided by several GPIO pins which support common protocols like I²C. The recent B-models have an 8P8C Ethernet port and the Pi 3 and Pi Zero W have Wi-Fi 802.11n and Bluetooth on board.
The first generation of the board had 256 MB RAM, split equally between the CPU and the GPU. The next generation doubled the RAM whereas the third generation doubled it further. Raspberry Pi 3 Model B released in February 2016, consists of on-board Wi-Fi, Bluetooth and USB boot capabilities. These boards are priced between US$5–35. As of 28 February 2017, the Raspberry Pi Zero W was launched, which is identical to Pi Zero, but has the Wi-Fi and Bluetooth functionality of the Raspberry Pi 3 for US$10.
The first-generation boards used the Broadcom BCM2835 SoC consisting of a 700 MHz ARM1176JZF-S processor, VideoCore IV graphics processing unit (GPU), and RAM. Cache is sized at 16 KB for L1 and 128 KB for L2. L2 cache is primarily used by the GPU. The pi 2 uses the BCM2836 SoC with a 32-bit quad-core ARM Cortex-A7 processor clocked at 900 MHz, with 256 KB shared L2 cache. The 3rd iteration of the pi employs the BCM 2837 Soc which further ups the game with a 64-bit quad core ARM Cortex-A53 processor clocked at 1.2 GHz, with 512KB shared L2 cache. The spec sheet is evident to map the increase in performance over the years. At 700 Mhz, the CPU on the first-generation raspberry pi provides a performance like the 300 MHz Pentium II, which has increased drastically in the third generation. The third iteration of the raspberry pi is estimated at about 10 times the performance of the pi 1stgen. The CPU chips under 1 GHZ on the first and second generation allow for overclocking up to 1GHz. The pi 2 can also be overclocked to 1500 MHz with proper cooling, which goes down the drain in case the chip reaches 85 degree Celsius.
Raspbian has been the most popular among the operating systems due to the boost provided by the Raspberry Pi foundation. It is a Debian based Linux operating system easily available at the foundation website. Some of the popular operating systems are:
· Ubuntu MATE
· Kali Linux
· Ubuntu Core
· Windows 10 IoT Core
· RISC OS
· Arch Linux ARM
· Android Things
Uses Of Raspberry Pi:
- Desktop PC.
- Wireless Print Server.
- Media Center.
- Retro Gaming Machine.
- Mine craft Game Server.
- Robot Controller.
- Stop Motion Camera.
- Tablet & Phone.
- Web Sever & VPN.
1. You can install a fully fledged Operating System (eg Raspbian which is Linux-based or Windows IOT Core which is Windows based OS) and use it as a day to day computer.
2. The presence of GPIO (General Purpose Input Output pins) is what distinguishes a RPi from traditional computers. You can connect these pins to sensors and external components and interact with them programatically using a language such as Python. This allows you to build and prototype Internet of Things devices that can sense the real world.
3. Newer models like the RPi has wifi and bluetooth built in. This allows you to take projects into wireless mode easily.
1. There is not any fuse protection on the Rpi, so if you connect pins incorrectly, you can damage the board.
2. It is not as fast in terms of CPU processing speed nor does it have as much memory as traditional PC or laptops. But for $35, it packs quite a punch.
3. There is no built in analog to digital conversion on the GPIO pins like there is in Arduino. So you need to have an ADC chip to work with analog signals when you need more accuracy.