[Info-vax] OT: IA-128 ???

[Neil Rieck]

On Oct 18, 11:41 am, VAXman-  @SendSpamHere.ORG wrote:
> In article <4adb2f09$0$275$14726... at news.sunsite.dk>, =?ISO-8859-1?Q?Arne_Vajh=F8j?= <a... at vajhoej.dk> writes:
>
>
>
> >glen herrmannsfeldt wrote:
> >> Arne Vajh?j <a... at vajhoej.dk> wrote:
> >> (big snip)
> >>> A VAX is 32 bit because the application use 32 bit virtual addresses.
> >>> Physical addresses is something else.
>
> >>> I can not comment on PDP-11.
>
> >>> I seem to recal that physical addresses of later VAX'es were bigger
> >>> than 32 bit, but 40 bit sounds too much - that would be 4 TB of RAM.
>
> >> I have sitting here the "VAX Architecture Reference Manual"
> >> which includes specifications for some VAX.
>
> >> The last one here is the 8800.  The "Physical address space" is,
> >> of course, 32 bits, but only 29 bits address installed memory.
> >> Above that is BI#0, multicast, boot ROM, reserved, node private space,
> >> reserved, node 0 through node 15, reserved, BI#1 through BI#3, and
> >> then more reserved.
>
> >> So up to 512MB of actual memory.
>
> >It was increased later.
>
> >Some googling indicate that I remember wrong the increase of
> >physical addressing was to 32 bits.
>
> >Source:
> >  http://labs.hoffmanlabs.com/node/131
>
> >Arne
>
> Late models of the VAX opened up the addressing to the full 32 bits.
> This meant that you could have as much as 3.5 GB of physical memory.
> 512MB of the address space was still reserved for I/O.  4GB - 512MB.
>
> --
> VAXman- A Bored Certified VMS Kernel Mode Hacker    VAXman(at)TMESIS(dot)ORG
>
>  http://www.quirkfactory.com/popart/asskey/eqn2.png
>
>   "Well my son, life is like a beanstalk, isn't it?"

We owned a 6430 with 256 MB but heard about 66x0 systems with 1 GB. We
also heard about 3.5 GB support on VAX 7000. Why do I bring this up?
Anyone with schematics for the XMI bus saw more than 32-bit addresses.
IIRC, there were at least 36-bits (maybe more).

Maybe someone with a better memory (no pun) than mind would like to
add two-bits worth.

NSR