Re: No kernel output on MicroVAX 3100-30

[Charles Dickman <chd%chdickman.com@localhost>]

On Thu, Sep 6, 2018 at 11:34 PM Erno Palonheimo <esp%iki.fi@localhost> wrote:
>
> On Thu, Sep 06, 2018 at 08:29:30PM -0400, Charles Dickman wrote:
> > On Thu, Sep 6, 2018 at 3:41 AM Erno Palonheimo <esp%iki.fi@localhost> wrote:
> > >
> > > On Sat, Sep 01, 2018 at 10:27:33AM +0200, Anders Magnusson wrote:
> > > > Den 2018-09-01 kl. 10:12, skrev Erno Palonheimo:
> > > > >On Sat, Sep 01, 2018 at 12:56:22AM +0200, Johnny Billquist wrote:
> > > > >>>Any ideas?
> >
> > What about memory size?
>
> 24 megabytes, shouldn't be a problem - and wasn't. I suppose 8.0 could
> run in 12 megabytes, possibly even 8.

8.0 boots fine on my VAXstation 4000 model 60 with 104MB.

8.0 does NOT boot on a VAXstation 3100 model 30 with 16MB. I was not
able to get it to net boot install.ram or the GENERIC kernel. Both
restart right after the loader progress lines showing sizes finishes.
There are problems on some machines (MVII and MVIII for sure) when the
kernel size gets close to 4MB. These machines have SG DMA maps only
capable of mapping 4MB. boot doesn't change the mapping, so everything
has to fit into the first 4MB. This may not be the problem Erno is
seeing, but it is a problem.

The 3100 does boot 1.6 from the disk after 15 years. That kernel is
only about 850k

-chuck