What is One instruction set computer?
A '''One Instruction Set Computer''' ('''OISC''') is an [[abstract]] [[computer]] that uses only one [[Instruction (computer science)|instruction]] (with no need for a [[machine language]] [[opcode]]). Such [[computer]]s are the extreme case or the logical conclusion of [[Reduced instruction set computer]]s, although the concept has been used only in [[academic]] [[Study circle|circles]], as a teaching aid like the URISC. The '''Ultimate RISC''' ('''URISC''') is the name given by [[research]]ers at the [[University of Waterloo]] in the city of [[Waterloo, Ontario|Waterloo]], [[Ontario]], [[Canada]], to their implementation of a single-instruction computer. URISC allows complete description of a fully functional [[computer]], in only a few pages. == References == * [http://catb.org/~esr/retro/ The Retrocomputing Museum] * [http://www.maxim-ic.com/products/microcontrollers/maxq/ MAXQ product line homepage] {{Webarchive|url=https://web.archive.org/web/20090728041600/http://www.maxim-ic.com/products/microcontrollers/maxq/ |date=2009-07-28 }} * [http://www.sccs.swarthmore.edu/users/06/adem/engin/e25/finale/ OISC Implementation with subleq] {{Webarchive|url=https://web.archive.org/web/20151121172708/http://www.sccs.swarthmore.edu/users/06/adem/engin/e25/finale/ |date=2015-11-21 }} * Univ. of Waterloo URISC: F. Mavaddat and B. Parhami, [http://www.ece.ucsb.edu/~parhami/pubs_folder/parh88-ijeee-ultimate-risc.pdf URISC: The Ultimate Reduced Instruction Set Computer], ''Int'l J. Electrical Engineering Education'', Vol. 25, No. 4, pp. 327-334, October 1988. * Univ. of Iowa Ultimate: [http://www.cs.uiowa.edu/~jones/arch/risc/ RISC] (Accessed November 2008). == Other websites == * [http://eigenratios.blogspot.com/2006/09/mark-ii-oisc-self-interpreter.html Mark II OISC Self-Interpreter] Possibly the first-ever OISC self-interpreter. * [http://bitstuff.blogspot.com/2007/02/subtract-and-branch-if-negative.html SBN Computer] * [http://mazonka.com/subleq/ SUBLEQ compiler and emulator] {{Webarchive|url=https://web.archive.org/w