以統一模型語言於嵌入式系統行程管理之分析

Abstract

由於VLSI技術不斷的快速發展，當Microprocessor的體積越便越小，價格越來越便宜的同時，市面上開始出現有Microprocessor〝嵌入〞的產品。舉凡PDA、手機、數位相機…等產品，皆可稱為嵌入式裝置。然而，這類的產品在軟體的需求上，大多必須具備高可靠度，效能要好，發展的時程短等特性。因此當我們發展一套嵌入式系統時，我們就必須考慮其架構是否具有彈性、合理以增加系統的穩定度及可靠度。而行程管理則與效能有著密不可分的關係，適當的行程管理方式將有助於提昇嵌入式系統的效能。 統一模型語言是一種標準語言，其用途在於塑模(Modeling)，也就是畫軟體藍圖。一套軟體系統的建構必須有適當的分析設計藍圖，因為軟體開發的過程絕對不是任意的、隨性的、且戰且走的、天馬行空的。因此在軟體開發的過程中必須將需求、分析、設計、實作、佈署等各項工作流程之構想與結果予以呈現，這就是軟體系統之塑模。 由於嵌入式系統的資源有限，行程管理可說是整個嵌入式系統效能的關鍵。在此篇論文我們將針對嵌入式系統的行程管理方法及軟體系統之塑模概念，做一系列詳細的分析與探討，利用統一模型語言來驗證行程管理方法的效能，以驗證其有效性。

Today, as microprocessors have become smaller and cheaper, more and more products have microprocessors “embedded” in them to make it “smart”. Such products are cell phone, PDA, digital camera…etc. Those embedded systems must respond to external events and cope with all unusual conditions without human intervention. However embedded computer applications are requiring more performance, higher reliability, stability, and lower development and maintenance costs. The Unified Modeling Language (UML) is a standard language for writing software blueprints. It is a graphical language for visualizing, specifying, constructing, and documenting the artifacts of a software-intensive system. A model provides the blueprints of a system. And we need to build models of complex system because we cannot comprehend such a system in its entirety and we can better understand the system we are developing. In this paper, we will discuss about the embedded real time system process scheduling, which is using UML-based to analyze it. The goal is proving RT UML Profile (RTP) can be used in analyze real time process scheduling. Base on our analysis, we demonstrate that UML is workable on embedded system process scheduling. And using UML to analyze real time system process scheduling can increase process-scheduling algorithm’s readability and reusability.