Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.csd.uwm.edu!cs.utexas.edu!uunet!mcsun!hp4nl!philapd!ssp1!roelof From: roelof@idca.tds.PHILIPS.nl (R. Vuurboom) Newsgroups: comp.arch Subject: Re: Instruction (dis)continuation Summary: Instruction continuation discontination? Message-ID: <231@ssp1.idca.tds.philips.nl> Date: 25 Aug 89 18:21:08 GMT References: <1989Aug24.215104.156@mentor.com> Organization: Philips Telecommunication and Data Systems, The Netherlands Lines: 28 I've noticed that motorola has moved from instruction continuation (68010-30) to instruction restart (68040). So they no longer support virtual machines. (Must be the processors got tired of puking their insides all over the stack. :-) Quoting the 68030 manual: Instruction continuation is used to support virtual I/O devices in memory-mapped input/output systems. Control and data registers for the virtual are simulated in the memory map. An access to a virtual register causes a fault and the function of the register is emulated by software. Anybody know why this instruction discontinuation? Is virtual machine emulation a lovely idea whose time has come and gone? Or does it use too many hardware resources? I think some (all?) of the risc processors use instruction restart (mips if I remember correctly) so are we looking at the end of instruction continuation? -- I don't know what the question means, but the answer is yes... KLM - Koninklijke Luchtvaart Maatschappij => coneenclicker lughtfart matscarpie Roelof Vuurboom SSP/V3 Philips TDS Apeldoorn, The Netherlands +31 55 432226 domain: roelof@idca.tds.philips.nl uucp: ...!mcvax!philapd!roelof