The Raspberry Pi: A Technology Disrupter, and the Enabler of Dreams

The Raspberry Pi Foundation aims to promote the teaching of Computer Science and is inspired by devices such as the ZX81 and Spectrum [1], the first home computers from the 1980s, and government backed in-school devices such as the BBC Acorn [2]. The first Raspberry Pi device was released in February 2012 (Raspberry Pi 1 Model B, generation 1). It proved to be an immediate success, in part due to the low $35 price. By adding a few peripherals, which are not included (keyboard, mouse, monitor, SD storage), it is possible to quickly have a fully working computer running Raspbian, a Debian-based Linux operating system. It is often referred to as a Single Board Computer (SBC), meaning that it runs a full operating system and has sufficient peripherals (memory, CPU, power regulation) to start execution without the addition of hardware. The Raspberry Pi can support multiple operating system variants and only requires power to boot. Some Raspberry Pi versions can boot direct from network but generally file-system storage is required, for example a micro SD card. Although other Single Board Computers (SBC) existed before the Raspberry Pi, historically they targeted industrial platforms such as vending machines and are often referred to as development boards. The Raspberry Pi Foundation made the SBC accessible to almost anyone, introducing not just a low cost computer, but one that can bridge the gap to the physical world by exposing General Purpose Input-Output (GPIO) connection pins. The Raspberry Pi pin header can be controlled programmatically from the operating system and supports a range of features, e.g., USB, UART, SPI, I2C and Interrupts, which can be used to connect a huge variety of electronic components. This has led to the popularity of the Raspberry Pi, not only in education but with industry, hobbyists, prototype builders, gamers and the curious. It has enabled people to experiment in new ways, for example incorrectly connecting sensors to GPIO pins can result in a broken mainboard, this is less inconvenient if it is a Raspberry Pi but, catastrophic if it is the family PC. The increase in popularity of Cyber Physical Systems (CPS) and the Internet of Things (IoT) has renewed the demand for embedded systems, on a large scale, greatly benefiting the Raspberry Pi. This demand is driven by the desire to instrument and understand the fabric of human civilisations ranging from cities to forests, in order to gain insights and produce actions, for example Smart Cities, Smart Cars, Smart Homes. This is achieved by sensor networks and their communication systems, the main driver is the falling cost of hardware and improvements in performance. Some predictions state that there will be 50 billion IoT devices by 2020 [3] which, although probably an over estimate, demonstrates a huge demand and opportunity for SBC applications.