Shuhaizar Daud

The effects of CPU load & idle state on embedded processor energy usage

Device power consumption is a serious design consideration especially for embedded systems. By reducing the power consumption of a particular system, we could effectively prolong the runtime of the system, allowing for longer operational condition of a particular system. Previous studies have suggested that the power characteristics of a modern embedded processor have since been improved with manufacturers implementation of better energy-focused designs. Implementation of hardware optimization such as better clock and power gating have been shown to produce better energy usage during on-load and off-load processing. In this paper we benchmarked the energy use of a modern embedded processor and study the effects of idling time to the processor and system energy usage. We have found that the processor energy use is significantly reduced in the instant that the processor goes idle during the execution process. The idling time during a processing timeslice allows the processor to use significantly less energy without explicitly depending on a frequency scaling algorithm to reduce energy consumption. This power saving feature directly implemented inside the processor hardware have the possibility to render software based frequency scaling algorithm and DVFS method to be less effective in reducing energy usage.

The effects of compiler optimisations on embedded system power consumption

Power consumption is a subject of serious consideration in embedded systems design because embedded systems are constrained to stringent power and energy requirements. The mission of lowering power consumption and energy usage of such systems is an important task to prolong their usage in real time situations. In this paper, we study the effects of compiler optimizations on embedded systems energy usage and power consumption in real time situations and the importance of running efficient binary codes in realizing a more power efficient, and better performing embedded system. Compiler optimizations at various levels involving different architectural features have been experimented and it is shown that architecture driven compiler optimizations have a better impact on reducing power consumption and energy usage in embedded system than blind code optimizations.

Web-based wireless data acquisition system using 32bit single board computer

The design and architecture of a Web-based wireless data acquisition system are presented. This system provides a Web interface for remote monitoring of sensors deployed which connected using wireless technology. The design utilizes the 32 bit single board computer as processor board to provide low cost and low power data acquisition system. Two main part of this system are Sensor Node (SN) and Web Server (WS). The SN is function as Data Acquisition Unit which contains processor board and connected to analog inputs while WS function as storage unit. The transmission of collected data between SN and WS is using 802.11b wireless network technology. This system is preferably deploy for large monitoring system such as for agriculture and environmental.

Improving system performance through operating system optimization on embedded devices platform

Implemented with a low speed CPU, small memory footprint, low static memory storage and developed specifically for low power requirement, small embedded devices are significantly affected by processing time. By cutting down processing time needed to complete a certain task, not only power consumption could be reduced, but it could also lead to greater system performance without the need to redevelop the current system. In this paper, we propose a system optimization technique through operating system optimization implemented during the OS compilation stages. Results obtained shows that a proper compiler optimization during the OS development stages could lead to a more than 100% speed increase on code execution performance, code loading sequences and library linking procedures. This greatly improves total system performance and reduces the time for a particular system to complete itspsila tasks and effectively reduces system turnover time without requiring a major overhaul on the software and hardware side.