A Generic Middleware for External Peripheral State Retention in Transiently-Powered Sensor Systems

Abstract

Sensor systems powered by energy harvesting usually include batteries or supercapacitors which impact the system cost and size, need time to be charged and are not environmentally friendly. In recent years, designers have proposed a new concept called transient computing that aims to remove these energy storage units and retain the system's state between power outages, in order to cope with an unreliable energy source. However, existing approaches cannot retain the state of external peripherals or are specific to certain peripherals, i.e. they are not generic. This poster proposes a generic middleware, capable to retain the state of external peripherals that are connected to a microcontroller through SPI. The validation shows the proposed approach retains the peripheral configuration between power failures with a maximum time overhead of 15% when configuring the peripheral. However, this represents a 0.77% overhead for a complete example application, which is lower than that caused by existing approaches.