由於奈米製程的進步，VLSI也進入奈米製程，進入奈米製程之後，chip中線與線的距離相當的短，在一些異常的環境下，chip的線路會產生短暫的錯誤，在這種情形下我們要將錯誤偵測出來，在這篇論文中，我們使用Reed Solomon code來幫助我們進行錯誤的偵測，Reed Solomon code是一個強大的錯誤偵測工具，在偵測階段，Reed Solomon code會產生16-bits的Parity Symbol，這些16-bits的Parity Symbol會被嵌入到記憶體來降低記憶體的overhead，Reed Solomon code的偵測計算也相當地簡單，處理器不需等待錯誤偵測完畢才進行執行的動作，Reed Solomon code不僅是一個強大的錯誤偵測工具，也有很強大的錯誤修復能力，在VLIW的容錯領域中，尚未被提出擁有錯誤修復的容錯系統，在這篇論文中，我們也會利用Reed Solomon code來幫助錯誤修復，Reed Solomon code的錯誤修復是以symbol計量，在此篇論文中我們分別實作one-symbol recovery 和two-symbol recovery來比較他們的錯誤修復能力。

In this paper, we base on data computing blocks (DCBs) and Reed Solomon code watchdog technology to implement VLIW watchdog processor. There are 16-bits parity symbol will be computed by Reed Solomon code watchdog scheme. These generated signatures are embedded into the instruction memory and then used to do the run time error checking. In this paper, the processor degradation can be improved by doing the whole block error checking after the branch instruction, the fault detection latency is improved by doing the intermediate error checking at the R-type instruction, and the memory overhead is reduced by storing the parity symbol to the R-type instruction. The experimental results show that the proposed watchdog has very high error detection coverage and shortest error detection latency to detect either single fault or multi-faults, no matter what the fault is transient or intermittent. In VLIW fault tolerance, error recovery has not been proposed. Reed Solomon code has good recovery ability. In this paper, we also implement recovery ability in the watchdog. The symbol which Reed Solomon code defines is a measure of recovery. We implement one-symbol recovery and two-symbol recovery and compare the recovery ability. The experiment result shows that two-symbol recovery is better than one-symbol recovery.

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