Design and Implementation of eRTOS Real-time Operating Systems for Wearable Computers

웨어러블 컴퓨터를 위한 저전력 실시간 운영체제 eRTOS 설계 및 구현

  • 조문행 (충남대학교 컴퓨터공학과) ;
  • 최찬우 (충남대학교 컴퓨터공학과) ;
  • 이철훈 (충남대학교 컴퓨터공학과)
  • Published : 2008.09.28


In recent years, embedded systems have been expanding their application domains from traditional embedded systems such as military weapons, robots, satellites and digital convergence systems such as celluar phones, PMP(Portable Multimedia Player), PDAs(Personal Digital Assistants) to Next Generation Personal Computers(NGPCs) such as eating PCs, wearable computers. The NGPCs are network-based, human-centric digital information devices diverged from the traditional PCs used mainly for document writing, internet searching and database management. Wearable computers with battery capacity and memory size limitations have to use real-time operating systems with small footprints and low power management techniques to provide user's QoS in spite of hardware constraints. In this paper, we have designed and implemented a low-power RTOS (called eRTOS) for wearable computers. The implemented eRTOS has 18KB footprints and the dynamic power management and the device power management schemes are adapted in it. Experimental results with wearable computer applications show that the low power techniques could save energy up to 47 %.


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