[Simh] NetBSD 5.1 on MicoVAX 3900 boot error

[Mark Pizzolato]

On Saturday, April 22, 2017 at 12:55 PM, Anders Magnusson wrote:
> Den 2017-04-22 kl. 18:01, skrev Mark Pizzolato:
> > [...]
> >> qt0 at uba0 csr 174440 vec 764 ipl 17
> >> qt0: delqa-plus in Turbo mode, hardware address 08:00:2b:d3:52:d9
> > [...]
> >
> > Thanks for checking this Peter.
> >
> > Meanwhile, since NetBSD 6.1.5 works, and NetBSD 5.x.x doesn't, these
> > questions arise:
> >     1) What is different in that driver between those NetBSD versions?
> I looked at the CVS logs and no bugfixes to the qt code.

That is VERY strange.  Simh v3.9 detects the DELQA-PLUS (DELQA-T) as
a DEQNA/DELQA and not as the turbo case.  So it uses qe vs qt.  The
4.x simulation has some better emulation of the support which allows
the different devices to be detected.  BOTH NetBSD 5.x and NetBSD 6.x
detect it as a turbo DELQA, 5.x crashes.  I'm going to look at what both
5.x and 6.x do during their device probes to see if there is a difference.
If all of the ways the device is being probed are the same, then 
the problem will lie somewhere else. 

> >     2) Why were these differences introduced?
> >     3) Are you sure the qt driver NetBSD 5.x.x truly worked on real hardware?
> I have had a 3900 using qt since loong time ago, running NetBSD 5 at last.
> Not around for me anymore though.
> >     4) If so, can we test that today (with real hardware)?
> >
> I might have a MV2 to test on, but not in the near future, so hopefully
> someone else on this list can try?

That would be useful...

Thanks.

- Mark