Developer | BBC Learning, BBC R&D, ARM Holdings, Barclays, element14, NXP Semiconductors, Lancaster University, Microsoft, Samsung, Nordic Semiconductor, ScienceScope, Technology Will Save Us, Python Software Foundation |
---|---|
Type | Single-board microcontroller |
Release date | v1: 10 February 2016 [1] v2: 13 October 2020 [2] |
CPU | v1: Nordic nRF51822, 16 MHz ARM Cortex-M0 core, 256 KB Flash, 16 KB RAM [3] [4] v2: Nordic nRF52833, 64 MHz ARM Cortex-M4 core, 512 KB Flash, 128 KB RAM |
Connectivity | Bluetooth LE, MicroUSB, edge connector |
Website | microbit |
The Micro Bit (also referred to as BBC Micro Bit or stylized as micro:bit) is an open source hardware ARM-based embedded system designed by the BBC for use in computer education in the United Kingdom. It was first announced on the launch of BBC's Make It Digital campaign on 12 March 2015 [5] [6] with the intent of delivering 1 million devices to pupils in the UK. The final device design and features were unveiled on 6 July 2015 [7] whereas actual delivery of devices, initially planned for September 2015 to schools and October 2015 to general public, [8] began on 10 February 2016. [9] [10]
The device is described as half the size of a credit card [11] and has an ARM Cortex-M0 processor, accelerometer and magnetometer sensors, Bluetooth and USB connectivity, a display consisting of 25 LEDs, two programmable buttons, and can be powered by either USB or an external battery pack. [3] The device inputs and outputs are through five ring connectors that form part of a larger 25-pin edge connector. In October 2020, a physically nearly identical v2 board was released that features a Cortex-M4F microcontroller, with more memory and other new features.
The physical board measures 43 mm × 52 mm and, in its first production run [update] , [12] included:
I/O includes three ring connectors (plus one power one ground) which accept crocodile clips or 4 mm banana plugs [19] as well as a 25-pin edge connector with two or three PWM outputs, six to 17 GPIO pins (depending on configuration), six analog inputs, serial I/O, SPI, and I²C. [17] Unlike early prototypes, which had an integral battery, an external battery pack (AAA batteries) can be used to power the device as a standalone or wearable product. [4] [11] [15] Health and safety concerns, as well as cost, were given as reasons for the removal of the button battery from early designs. [20]
The available hardware design documentation consist of only the schematic and BOM distributed under the Creative Commons By Attribution license, no PCB layout is available. [21] [22] The compatible reference design by Micro:bit Educational Foundation, however, is fully documented.
v2, released on 13 October 2020, includes: [23]
In micro:bit v2, the reset button can be used to turn the board off by holding it for 3 seconds. [24] [25] [26]
There are three official code editors on the micro:bit foundation web site:
The Python programming experience on the Micro Bit is provided by MicroPython. [28] [29] Users are able to write Python scripts in the Micro Bit web editor which are then combined with the MicroPython firmware and uploaded to the device. Users can also access the MicroPython REPL running directly on the device via the USB serial connection, which allows them to interact directly with the Micro Bit's peripherals.
The Micro Bit was created using the ARM mbed development kits. The run-time system and programming interface utilize the mbed cloud compiler service to compile the user's code into a .UF2 file. The compiled code is then flashed onto the device using USB or Bluetooth connections. The device appears as a USB drive when connected to a computer, and code can be flashed dragging and dropping the .UF2 file. [18]
Other editors for the BBC micro:bit include:
Other programming languages for the BBC micro:bit include:
Operating systems which can be built for the BBC micro:bit:
The micro:bit was designed to encourage children to get actively involved in writing software for computers and building new things, rather than being consumers of media. [3] It was also designed to work alongside other systems (such as the Raspberry Pi [30] ) and build on BBC's legacy with the BBC Micro for computing in education. The BBC planned to give away the computer free to every Year 7 (ages 11 and 12) child in Britain starting from October 2015 - around 1 million devices. [4] [20] In advance of the roll-out an online simulator was made available to help educators prepare and some teachers were to receive the device in September 2015. [3] The device was planned to be on general sale by the end of 2015. [3] [31] However, problems delayed the launch until 22 March 2016. [8]
The BBC had a difficult decision to choose which year group would be the first to receive the free micro:bits, and the BBC's head of learning said that the reason they "plumped for Year 7, rather than Year 5, is it had more impact with that age group as they were more interested in using it outside the classroom". [31]
Planning for the project began in 2012 as part of the BBC Computer Literacy Programme, and by the time of the launch in July 2015 the BBC had taken on board 29 partners to help with the manufacturing, design, and distribution of the device. [32] [33] The BBC has said that the majority of the development costs were borne by the project partners.
The development of the Micro Bit is a product of a number of partners working with the BBC:
A prototype device and software stack created by BBC R&D, demonstrated in the initial announcement, [39] was used to test the proposition in schools, and to provide a reference specification for the partnership to build upon. [40]
After a successful roll-out of the micro:bit across the UK, the BBC handed over the future of the BBC micro:bit, and adoption in other parts of the world, to the newly formed, not-for-profit Microbit Education Foundation. [41] [42] The announcement was made on 18 October 2016 to a small group of journalists and educators at Savoy Place in London, [43] that included a review of the past year and their plans for the future. The transition from the BBC to the micro:bit Education Foundation moved the official home of the micro:bit from microbit.co.uk to microbit.org.
The BBC licensed the hardware technology as open source and allows it to be manufactured around the world for use in education. The foundation oversees this. [31] [32]
On 2 January 2018, it was announced that Gareth Stockdale from BBC Learning would succeed Zach Shelby as CEO of the Microbit Educational Foundation. [44]
The foundation is also providing a fully documented reference design of a device different from the marketed, but software compatible, with the intention of easing the independent development and manufacturing of micro:bit derived devices and products. [45] The reference design is open source hardware, but unlike the marketed device employing a CC BY 4.0 license it is distributed under the terms of the Solderpad Hardware Licence, Version 0.51. [46] The available design documentation for the reference design includes both schematic and circuit board layout in several EDA suite formats. [47]
On 13 October 2020, the Micro:bit Educational Foundation has announced a revised version of micro:bit. Available for the same price as the original micro:bit and sharing its general design, micro:bit v2 includes Nordic nRF52833 CPU (ARM Cortex-M4, 64 MHz, 128 KB RAM, 512 KB flash), and additionally a microphone, a speaker, a touch sensor, and power saving mode. [2]
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…we plugged them into a Nordic NRF51822 development kit, which uses the same chip as the micro:bit…
The BBC micro:bit is based on the mbed HDK. The target MCU is a Nordic nRF51822 with 16K RAM, 256K Flash. As well as the nRF51822 there's also an onboard accelerometer and magnetometer from Freescale.