ARM provided the technical design for the BBC micro:bit, Technology Will Save Us was responsible for the device's appearance, Nordic Semiconductor donated the main Cortex-M0 microprocessor, while Freescale provided the accelerometer, magnetomer compass and another Cortex-M0 MCU to manage the device's micro USB connection. Crucially, element14 helped organise the device's manufacture and the sourcing of parts.
"We became aware of the project back in February and put forward a proposal to support with the design, cost optimisation and manufacturing," said Richard Curtin, global director of strategic alliance, element14. "We've managed other projects, designing and manufacturing development kits in our strategic alliance programme."
According to Curtin, the project highlights the work required to bring a new board to market.
"When we joined, there were a number of unknowns and element14 was invited to arbitrate between the needs of the working group and the practicalities of manufacture," he explained.
The initial design was amended significantly, according to Gary Atkinson, director of emerging technologies at ARM. "We wanted to make the device mbed compatible and to improve its connectivity. I think we came up with a more capable device as a result of the changes we made to the initial prototype."
"Our role was to take these prototypes and optimise them for mass manufacturing," Curtin noted.
Micro:bit's success will depend on its life beyond the initial rollout, so the partners worked to ensure that it was an affordable product, capable of creating a niche for itself in the growing education market.
"Because of our V-score process, which helps to strengthen the board and makes panel separation easier after assembly, we reduced the cost of the board significantly, without sacrificing the quality of the finish," said Curtin.
"The appearance of the board was also important. In most development kits, that is secondary to functionality. But as this board is aimed at children, it needed to be both functional and friendly and we worked hard with our partners to realise the manufacturing realities behind these design decisions," Curtin he added.
Cost optimisation is crucial to all successful board designs.
"In this case, the BBC was aiming to reduce the cost of the board to the point where it could be provided at zero cost to every 11 and 12 year old in the country. To assist in this, we worked with supplier partners to leverage economies of scale. While this is possible in higher volume production runs, with smaller projects it can be more difficult."
Finally, the project had to be manufacturable at scale.
"We had to find someone who could manufacture the board in the quantities required and within the aggressive timelines of the project," said Curtin, "and, in this case, we are working with IO Note in China.
"As the design was being created in the UK, initial prototypes were manufactured in the UK. This allowed the partners to test early prototypes, write the key software components, debug quickly and move onto the next stages of the design – quick turn manufacturing in practice."
Finally, mass production is set to start shortly and 1m boards will be in schools by the autumn.
"There are many layers to designing and manufacturing a new board," Curtin concluded, "but we have been able to turn an idea into reality in a matter of months."