防篡改保護您的寶貴的基于MCU的系統IP

　　基于MCU的設計可以很容易地添加專門化和差異化的功能，通過編碼到設備的算法。一個新的扭曲舊的算法或一個全新的方法可以使成功的產品和失敗之間的區別。不幸的是，使用單片機也可以打開你的設計逆向工程，其中一個競爭對手竊取你的辛勤工作和你的創新的好處。當然，律師可以參與，也許報復，但往往只有在損害已經完成。一個更好的方法是保護您的設計免受常見的硬件篡改入侵，用于訪問您的代碼和竊取您寶貴的知識產權。

　　本文將介紹一些常見的硬件“黑客”的方法來獲取您寶貴的設計IP。新的MCU包括幾個關鍵的功能，可以用來放一些障礙來防止硬件篡改。這些防篡改保護設計技術可以成為MCU設計者的技術“技巧的一個重要組成部分。”

　　On-chip tamper prevention： supervisor mode

　　One of the more recent innovations in MCUs has been the inclusion of a feature that has been used in standard CPUs for many years. One of the earliest tamper-prevention features， separating the user-operating mode from the supervisor-operating mode （the supervisor mode is often associated with the operating-system mode in CPUs） has been showing up in MCU devices. This capability allows supervisory software to have privileged access to protected resources while limiting or eliminating access to less privileged user programs. This makes it much more difficult for a hacker to gain control of the system via user software code bugs. Even if a user bug can be used to gain control of the MCU， it will still be stuck in the user mode without access to the most important system elements related to configuration， programming， debugging， and system control.