Xref: utzoo comp.misc:3539 comp.sys.misc:1709 comp.os.cpm:1759 Path: utzoo!utgpu!attcan!uunet!steinmetz!davidsen From: davidsen@steinmetz.ge.com (William E. Davidsen Jr) Newsgroups: comp.misc,comp.sys.misc,comp.os.cpm Subject: Re: Z-80 Unix? Keywords: z-80 unix Message-ID: <12207@steinmetz.ge.com> Date: 23 Sep 88 18:36:00 GMT References: <278@pte.UUCP> <6288@xanth.cs.odu.edu> <2906@mipos3.intel.com> <704@tetra.NOSC.MIL> Reply-To: davidsen@crdos1.UUCP (bill davidsen) Distribution: na Organization: General Electric CRD, Schenectady, NY Lines: 19 In article <704@tetra.NOSC.MIL> budden@tetra.nosc.mil.UUCP (Rex A. Buddenberg) writes: | 2. What are implications for the follow-on Z-80 derivative chips | like HD64180 and Z-280? How portable are we here? If you can make | things work in a 64k RAM space, life ought to get easier if you can | lay hands on more RAM... Somehow sounds like an awkward fit though | until you get hardware memory management to take a lot of the load off | your code...muse,muse,muse. I hacked CP/M to live in an alternate memory bank (actually I ran it in the 2nd bank and had a faker in the main memory). Using that technique you could get more memory for UNIX and possibly run a lot more of it. That would allow you to have multiple processes, too, since there would be virtually no swap overhead. I don't know about i/o, I can't think of any *cheap* way to do it into an unselected bank. -- bill davidsen (wedu@ge-crd.arpa) {uunet | philabs}!steinmetz!crdos1!davidsen "Stupidity, like virtue, is its own reward" -me