Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!cs.utexas.edu!samsung!uunet!motcid!king From: king@motcid.UUCP (Steven King) Newsgroups: comp.sys.amiga Subject: Re: Cost of Multitasking, another urban myth Message-ID: <2158@grape3.UUCP> Date: 8 Apr 90 03:37:56 GMT References: <3137@bingvaxu.cc.binghamton.edu> <1990Mar14.174048.2508@tc.fluke.COM> <16965@well.sf.ca.us> Organization: Motorola Inc. - Cellular Infrastructure Div., Arlington Heights, IL 60004 Lines: 23 In article <16965@well.sf.ca.us> farren@well.sf.ca.us (Mike Farren) writes: >kurt@tc.fluke.COM (Kurt Guntheroth) writes: >>>1. Hardware X is too primitive to support multitasking >> You can multitask on the Z80. I believe there was even a unix (the >> old system 3 flavor) that ran on a fancy Z80 board. > >I was part of a team that designed a multitasking, multiuser system in >1977 - it used 8085's, the slightly snazzier version of the 8080. Worked >like a charm. Multitasking - it's not just a good idea, it's an OLD good >idea. My current job at Motorola is to maintain and update the operating system and processor fault management on a cellular telephone switch. This system (designed back around '77 as well) consists of six multitasking Z80s tied together in a multiprocessing environment. Each Z80 has support hardware to give it an effective address space of 16 Megabytes. Don't ever let 'em tell you a processor is "too primitive" for *ANYTHING*! :-) -- ---------------------------------------------------+--------------------------- It's only impossible until it's done. | Steve King (708) 991-8056 | ...uunet!motcid!king | ...ddsw1!palnet!stevek