能源消耗是嵌入式及行動式系統設計的重要考量，軟體控制功率管理是一個比硬體控制更有彈性的能源管理方法，然而以往的研究均只針對處理器或只針對週邊裝置作能源管理之研究，使得整個系統的功率消耗未被全盤考量。本論文提出一可以同時降低處理器及週邊裝置之功率消耗的排程演算法，其特點為根據系統的利用率來決定處理器之速度，使系統利用率低的時候可以用較低功率的運算速度節省能源的消耗，另一方面也去偵測週邊裝置的使用狀況，在不使用週邊裝置時，儘可能地關閉週邊裝置的電源或降低其電源消耗。此排程演算法可以很容易實作於即時作業系統中，使得系統電源不僅可以有效地運用，系統內的工作亦可以在設定之執行期限內執行完畢。本論文也以eCOS的架構為例說明系統如何建立功率管理介面及框架，使得設計功率管理時，可以有一致性的介面。

　　Energy consumption is an important design issue of embedded systems and portable devices. In achieving effective power management, software- controlled approach is usually more flexible than hardware-controlled approach. However, past researches only focused on the power management of either processor or device; power consumption of the whole system is not considered at all. This thesis presents a scheduling algorithm which takes into account the power consumption of both processor and devices. It has the feature of deciding speed of processor according to the system utilization such that it can use low power computing speed to reduce power consumption when system utilization is low. On the other hand, it also detects the usage of devices; it will shutdown the power of devices when device is idle. This scheduling algorithm can be implemented easily in real time operating system, such that power is comsumed more efficiently while tasks in the system can meet their deadline requirements. We also use the architecture of eCos to demonstrate how to build a power management interface and framework, such that it has the same interfaces when designing power management functionality.

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