Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10 5/3/83; site watcgl.UUCP Path: utzoo!watmath!watcgl!dmmartindale From: dmmartindale@watcgl.UUCP (Dave Martindale) Newsgroups: net.unix-wizards Subject: Re: VAX-11/780 Memory Message-ID: <520@watcgl.UUCP> Date: Thu, 23-Jun-83 00:50:41 EDT Article-I.D.: watcgl.520 Posted: Thu Jun 23 00:50:41 1983 Date-Received: Thu, 23-Jun-83 02:05:47 EDT References: <26922@linus.UUCP> Organization: U of Waterloo, Ontario Lines: 18 From my understanding of how the memory is remapped when the Interleave Enable bit is turned on (it appears that sequential locations from each controller remain in order but alternate, like a perfect cut and shuffle of a card deck at the quadword level) I can't see how UNIX could survive turning on the interleave bit once it had already been loaded into non-interleaved memory. The bootloader could do it more easily - it could make a copy of itself that would reassemble properly when interleaving was turned on, and then very carefully enable interleaving and jump to the new code. The simplest, and ugliest way would be to simply have the *boo.cmd files on the floppy that boot the machine stuff the appropriate numbers into the memory controllers to set their base addresses and enable interleaving. Anyone out there with interleaved memory on a 780 who can tell us what you do? For 750's, can you even put multiple memory controllers on them? If so, are they able to do interleaving? Dave Martindale