在對矽晶片除錯過程中，事件觸發技術被應用於監測一個電路或系統的狀態。當一個核心或系統的狀態滿足用戶所指定的事件或條件時，一些預先被設定好的除錯動作將會被觸發，例如將電路目前的狀態記錄下來或暫停正常運作的電路並取出電路內部資料且存放於記憶設備中。然而傳統的事件觸發技術通常只能觀察到一些數量有限並且需要預先定義的觸發信號，而這些限制使得事件觸發技術缺少重組觸發事件的能力。而在本論文中，我們提出了一個應用於單晶片矽除錯的電路核心事件觸發機制，它透過最常用的測試設計(掃描鏈)來監測一個待除錯電路內部的狀態。這個機制提供了許多強大的除錯能力，包括提取的掃描鏈上的任何內容、將多個觸發事件合併成一個單一的觸發條件、檢查觸發事件的排序順序、檢測指定的觸發事件發生的次數並可指定的一個搜索範圍來進行除錯。而我們使用硬體的方式來實現上述所有能力，因此可以有效率地對矽晶片進行除錯。我們將電路核心事件觸發機制實現在之前所開發的單晶片除錯平台中並提供了一個圖形視窗界面的硬體除錯工具用來支援事件驅動的除錯程序。實驗結果說明了我們所提出的電路核心事件觸發機制可以很方便的設置中斷點並檢查感興趣的暫存器，讓對硬體除錯就像對軟體開發進行除錯一樣，在觸發條件滿足時暫停正常運作的待除錯電路;當系統暫停時使用者可以檢查待除錯電路核心內部的所有狀態；而當檢查完成之後該系統可以恢復到其暫停之前狀態，然後使用者可以設置下一個觸發條件或進行單步執行的除錯。

Event-trigger techniques have been used to monitor the state of a core or system during post-silicon debugging. When a user-specified event or condition is satisfied, a pre-defined debugging operation such as snapshotting the current states of the core under debug and pausing the normal operation to enable the dumping of storage devices will be activated. However, the traditional event-trigger techniques usually can only observe a limited number of pre-determined trigger signals. They also lack the capability to reorganize the trigger events. In this work, we propose a flexible inside-core event-trigger mechanism that allows one to monitor all the internal registers of a core under debug through the most commonly employed test facility, i.e., scan chains. This mechanism provides several powerful debugging capabilities, including extracting the contents of any register on the scan chains, combining multiple trigger events into a single trigger condition, examining the sequencing order of events, detecting the number of occurrences of specified events, and performing debugging process in a specified search range. All the above capabilities are implemented in a hardware manner. Thus the silicon-debug process can be carried out efficiently. We have incorporated the inside-core event-trigger mechanism into an SOC debug platform, and provided a graphic user interface tool to support the event-driven debugging process. Experimental results show that the proposed inside-core event-trigger mechanism can facilitate breakpoint setting, examining the registers of interest and pausing the normal operation when the trigger condition is satisfied. The user can then examine the internal states of the core under debug when the system is paused. After the examination, the system can be recovered to its state right before it is paused. Thus the user can set another trigger condition or execute a single-step debug process, just like the debug process for software development.

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