Energy-aware software development for embedded systems in HW/SW co-design

Power constrains are becoming increasingly important for embedded systems, especially when considering mobile applications. These systems are characterized by the presence of a dedicated processor running application-specific software. Current approaches only focus on power optimization in one design domain, such as the hardware or the software one. However, to meet the tight power constrains, both have to be investigated in relation. This paper proposes a novel approach to support the software developing process which takes this relation into account. Based on hardware/software co-simulation, the power consumption of the hardware is annotated to the corresponding source code. Hence, the consumption of the system is directly visible during software refinements of the microcontroller. After each refinement cycle, an overall power optimization can be accomplished. The approach is applied to an example system which comprises the embedded software of a MSP430 microcontroller and its controlled external peripherals. Using the example, the potential of the approach is discussed. Moreover, the power annotation process is defined and the data exchange formats are specified. Therefore, the approach is also applicable to any other controller type.