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From: RAY@SRI-KL.ARPA
Newsgroups: mod.computers.vax
Subject: Re: physical address space on uVAX-II
Message-ID: <8601271951.AA19079@ucbvax.berkeley.edu>
Date: Mon, 27-Jan-86 14:29:16 EST
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Posted: Mon Jan 27 14:29:16 1986
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The Q-Bus can only map 4 meg of memory at one time. The uVAX-II uses
a separate bus, not the Q-Bus, for memory ( I believe the memory boards
get there power from the q-bus, however). Thus, you have a very similar
situation to the 78x class machines and their unibus dma transfers -
the actual memory on the machine is greater then the unibus's memory
mapping space.  

Ray
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