低功率有限狀態機狀態編碼

Abstract

功率消耗在超大型積體電路設計上很重要，當然在指定有限狀態機的狀態 時也不可以忽視．在本論文中，提出了一個在有限狀態機的輸入之訊號機 率及轉換機率給定的情況下，計算有限狀態機的狀態機率及狀態轉換機率 的方法．利用我們的方法所計算出的狀態機率和用狀態轉換表模擬的結果 相較之誤差皆在百分之十以下，比以前的方法準確許多．此外，我們提出 了一個新的狀態指定的方法，先把加權圖內的重要加權找出來，將其二端 的狀態指定成距離為１．以達到降低狀態線轉換次數較低的要求．實驗數 據顯示，使用此方法可降低約8%狀態線轉換次數. Power consumption is now an important issue in VLSI design, so is in Finite State Machine (FSM) state assignment. In this thesis, a model of computing FSM's state probability with given input signal probability and transition densities has been proposed. The difference between the state transition probabilities calculated by our approach and those by exhaustive simulation is less than 10%. It is a significant improvement in comparison with former methods. Besides, we propose a new method for state assignment, which choose some representative edges from the weighting graph to be assigned as distance one to minimize state line transition counts. Experimental results show that this method has reduce more than 8% of state line transitions.