ptoper@obelix (Andy Nagy) (02/09/91)
A question: The maximum stated address space for the A3000 is a mere 1.75 GB. What is the rest of the 4GB address space of the 68030 used for? (A detailed anwer would be appreciated.) ------------------------------------------------------------------------------- Andy Nagy (ptoper@asterix.gaul.csd.uwo.ca) The University of Western Ontario, London, Canada
daveh@cbmvax.commodore.com (Dave Haynie) (02/13/91)
In article <2207@ria.ccs.uwo.ca> ptoper@obelix (Andy Nagy) writes: > The maximum stated address space for the A3000 is a mere 1.75 GB. > What is the rest of the 4GB address space of the 68030 used for? > (A detailed anwer would be appreciated.) Cheap-ass A3000 memory map: $ff010000-$ffffffff Reserved $ff000000-$ff00ffff Zorro III autoconfig block $80000000-$feffffff Reserved $10000000-$7fffffff Zorro III board space $08000000-$0fffffff Coprocessor slot board space $07000000-$07ffffff A3000 Fast RAM $01000000-$06ffffff Reserved (future motherboard space) $00f80000-$00ffffff ROM $00f00000-$00f7ffff Production diagnostic ROM space $00e90000-$00efffff Zorro II I/O space $00e80000-$00e8ffff Zorro II autoconfig block $00e00000-$00e7ffff Reserved $00b80000-$00dfffff Motherboard I/O and reserved space $00a00000-$00b7ffff Zorro II I/O space $00200000-$009fffff Zorro II memory space $00000000-$001fffff Chip RAM The regions in 24 bit space are essentially the same as on 68000 based Amigas, though the optional "Ranger" memory chunk starting at $00c00000 doesn't contain any memory, of course. -- Dave Haynie Commodore-Amiga (Amiga 3000) "The Crew That Never Rests" {uunet|pyramid|rutgers}!cbmvax!daveh PLINK: hazy BIX: hazy "What works for me might work for you" -Jimmy Buffett
ckp@grebyn.com (Checkpoint Technologies) (02/16/91)
In article <18881@cbmvax.commodore.com> daveh@cbmvax.commodore.com (Dave Haynie) writes: >Cheap-ass A3000 memory map: > >$10000000-$7fffffff Zorro III board space Fine. But just before that you list: >$80000000-$feffffff Reserved Holy cow - that's why only 1.75GB, because nearly 2GB are "reserved". Is this a real hardware restriction? Or are you just ruling that area "reserved" because of dumb-a** programmers (compilers?) who do signed comparisons on addresses? -- First comes the logo: C H E C K P O I N T T E C H N O L O G I E S / / \\ / / Then, the disclaimer: All expressed opinions are, indeed, opinions. \ / o Now for the witty part: I'm pink, therefore, I'm spam! \/