Power Management System for Embedded RTOS: An Object Oriented Approach

Power management systems for embedded devices can be developed in operating system (OS) or in applications. If power management policy is applied in OS, then developers can concentrate only on application development. OS contains specific and accurate information about the various tasks being executed. Therefore, it is logical to place algorithms that place components not being used into lower power states. This can significantly reduce the energy consumption by the system. Real-time-operating-system (RTOS) has a comprehensive set of power management application programming interfaces (APIs) for both device drivers and applications within a power management component. In this paper, we provide abstracted concepts of a system power manager (PM), device power managers, and application power managers. We present relationship and interactions of these managers with each using Unified Modeling Language (UML) class diagrams, sequence diagrams and state charts. We recommend that PM must be implemented at operating system level in any embedded device. We also recommend the interfaces for interactions between PM and the devices power manager, as well as PM and application power manager. Device driver and application developers can easily use this object oriented approach to make the embedded system more power efficient, easy to maintain, and faster to develop