Re: CMD MSCP SCSI problems? (again?)

[Johnny Billquist <bqt%softjar.se@localhost>]

On 2023-02-08 21:05, emanuel stiebler wrote:
> On 2023-02-08 12:51, Johnny Billquist wrote:
> > On 2023-02-08 18:43, emanuel stiebler wrote:
> > > On 2023-02-01 15:12, Johnny Billquist wrote:
> > > > On 2023-02-01 21:10, emanuel stiebler wrote:
> > > > > On 2023-02-01 14:55, Anders Magnusson wrote:
> > > > >
> > > > > > ragge@MacBook-Pro-2.local:/Users/ragge/old/nbsdvax/sys/arch/vax/compile/obj/GENERIC 
> > > > > >
> > > > > > [   1.0000000] MicroVAX 3800/3900
> > > > > > [   1.0000000] total memory = 255 MB
> > > > > > [   1.0000000] avail memory = 242 MB
> > > > >
> > > > > a MicroVAX 3800 with 256MByte?
> > > >
> > > > simh... :-)
> > >
> > > Out of the box like this, or did you have to change some code?
> >
> > Um. In simh:
> >
> >
> > Gru:bqt/vax% microvax3900
> >
> > MicroVAX 3900 simulator V4.0-0 Current        git commit id: 721e2f42
> > sim> set cpu 128
> > sim> show cpu
> > CPU     idle disabled, model=VAXserver 3900 (KA655), NOAUTOBOOT
> >          Implementing: Base Instruction Group
> >          Emulating: Packed-Decimal-String-Group 
> > Extended-Accuracy-Group Emulated-Only-Group
> >          128MB, HALT to SIMH
> > sim> set cpu 256
> > sim> show cpu
> > CPU     idle disabled, model=VAXserver 3900 (KA655), NOAUTOBOOT
> >          Implementing: Base Instruction Group
> >          Emulating: Packed-Decimal-String-Group 
> > Extended-Accuracy-Group Emulated-Only-Group
> >          256MB, HALT to SIMH
>
> I guess, I'm getting rusty. Didn't think CVAX supported that. But then, 
> it was a limitation of the KA655 (and their little memory boards)

Oh, I bet the CVAX didn't bring out that many address pins.
But that was just a physical limitation. Architecturally, all VAXen up 
until NVAX had the same 1G physical address limit, divided into 512M of 
memory and 512M of I/O space.

NVAX could in theory address 16G, although the actual implementations I 
think only had 32 address bits brought out. But that was what the 
revised page table would have allowed.

simh is obviously not limited by physical hardware details. :-)

  Johnny

--
Johnny Billquist                  || "I'm on a bus
                                  ||  on a psychedelic trip
email: bqt%softjar.se@localhost             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol