Silabs/ARM co-operation adds power management API to mbed

March 13, 2015 // By Graham Prophet
A collaboration between Silicon Labs and ARM aims to “drive the future of low-power arm mbed IoT device platforms” - running mbed on Siliocn Labs EFM32 devices will accelerate deployment of energy-friendly Internet of Things applications, say the two companies.

The collaboration with ARM is to define and deliver the first power management application programming interfaces (API) for ARM mbed platforms. Adding power management APIs to mbed will bring energy efficiency to standards-based solutions optimised for ultra-low-power, battery-operated connected devices. The new APIs will enable the mbed community of more than 100,000 registered developers to optimise their mbed-enabled ARM Cortex-M architecture-based designs for the utmost energy efficiency and longer battery life.

In addition to enabling developers to manage processor and peripheral states, the mbed power management APIs are designed with real-world, low-energy application scenarios in mind. A new feature exposed by the APIs on Silicon Labs’ EFM32 Gecko microcontrollers (MCUs) automatically determines and enables the optimal sleep mode based on the MCU peripherals in use, which can dramatically reduce system-level energy consumption. Low-energy optimisation is achieved by enabling I/O operations to be executed in the background and by allowing those operations to continue even while the MCU core is in sleep mode or during other processing tasks.

The automatic selection of the optimal sleep mode, combined with low-energy, autonomous MCU peripherals, enables developers to significantly reduce the energy consumption of their IoT applications with minimal effort. For example, energy profiles of an application updating a clock display every second on a memory LCD – a common use case for IoT devices – have shown a current consumption reduction from 1.03 mA to 0.100 mA.

“The new power management APIs for ARM mbed make it possible for developers to create applications that take advantage of the low-power features of ARM Cortex-M based microcontrollers,” said Zach Shelby, vice president, IoT business marketing, ARM. “This is an important step toward enabling full energy-awareness in IoT devices, and it is one of the key building blocks for mbed OS that is due for public release later this year.”

Silicon Labs plans to provide mbed-enabled EFM32 Gecko starter kits in April 2015. Silicon Labs’ initial