我們在此提出一個可以減少8086嵌入式系統記憶體大小的方案。每一個指令中的欄位以一個代碼取代，此代碼先由arithmetic coding產生，再經由我們所提出的演算法重新編碼。而重新編碼是依據arithmetic coding編碼後的碼長來安排。一個重新編碼後的代碼，是由group codeword及offset組成。
重新編碼可以減少解碼單元中Content Address Memory的大小。我們設計一個即時解壓縮單元，把即將要被執行的程式解壓縮。因應解壓單元的需要，我們需要儲存一些解碼相關的資訊，然而這些資訊量是固定的。
因為程式壓縮的關係，可能導致被壓縮後程式不再儲存於原先規劃的記憶體位置中。因此一個Line Address Table將被用來做位置空間的轉換。
運用我們所提出的方案來壓縮8086程式，可達70﹪～75﹪的壓縮率。

We propose a method to reduce the size of memory usage in 8086 embedded applications. Each field in an instruction is substituted by a re-coded codeword. We use arithmetic coding algorithm to generate codeword first and re-code the codeword according to their length. A re-coded codeword is composed of a group codeword and an offset.
Re-coding can reduce the CAM (content address memory) size in decompression unit. We design a run-time decompression unit to decompress the compressed code on the-fly before execution. Several extra tables are used to keep the decompression information. The sizes of these tables are fixed.
The location of instruction branch target changes as a result of program compression. A LAT (Line Address Table) is used to translate the program address into the address of compressed instruction.
The compression ratio for some 8086 programs is about 70%~75% using our method.

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