Re: Halt in boot menu

[Anders Magnusson <ragge%ludd.ltu.se@localhost>]

On 07/28/2012 09:02 PM, Thor Lancelot Simon wrote:
> On Sat, Jul 28, 2012 at 12:58:12PM -0600, Michael L. Hitch wrote:
> > On Sat, 28 Jul 2012, John Klos wrote:
> >
> > > The halt command in the boot menu on VAXen doesn't really halt -
> > > wouldn't halt more likely drop one into the boot ROM prompt? It
> > > reboots using the default boot device. Sounds like a reboot
> > > command to me.
> > >
> > > Would anyone mind if I changed this?
> >    Change it to say reboot, or change it so it actually halts?
> >
> >    Some models require special setup for the "console program mailbox"
> > to indicate whether the halt instruction will halt or reboot.  The
> > halt routine in /boot just executes the halt instruction without doing
> > any of the setup required to tell the console to actually halt.
> Right, some models have a physical switch that controls the action,
> like the 11/750; I can't remember whether it can be overriden by software.
It cannot.  In fact, all big VAXen control what to do via either a switch on
the front panel or by altering the cli script on the console processor.
This cannot be changed from the vax software.

But, the microvaxes have the opportunity to change this so it seems to be a
good idea to check the hw type to see whether it can be changed, and in
that case how.  Shouldn't add too many bytes to the boot program :-)

-- Ragge