單一指令電腦(英語:one instruction set computer,OISC)也稱最簡指令集電腦(ultimate reduced instruction set computer,URISC),它是一種抽象電腦,該電腦只有一條指令[1][2][3]。巧妙地選取這一條指令,並且給予無限的資源,單一指令電腦就能成為和其他多指令電腦一樣的圖靈機[2]:55。在教學上,這種電腦被推薦來幫助理解電腦架構[2]:2[1]:327,同時,也能用它來研究電腦的結構模型[3]。
參考文獻
^ 1.01.1Mavaddat, F.; Parhami, B. URISC: The Ultimate Reduced Instruction Set Computer(PDF). Int'l J. Electrical Engineering Education (Manchester University Press). October 1988, 25 (4): 327–334 [2010-10-04]. (原始內容存檔(PDF)於2019-10-18).引文使用過時參數coauthors (幫助)
This paper considers "a machine with a single 3-address instruction as the ultimate in RISC design (URISC)". Without giving a name to the instruction, it describes a SBN OISC and its associated assembly language, emphasising that this is a universal (i.e., Turing-complete) machine whose simplicity makes it ideal for classroom use.