[Simh] autoboot

[Tim Pinkawa]

On 4/30/06, Villy Madsen <Villy.Madsen at shaw.ca> wrote:
> Autoboot when you start VAX
> i.e.  I want VAX to autoboot the cpu (If it can't already, then that
> shouldn't be hard to do)
> and then I want the 3900 console to autoboot.
>
> I'm reasonably sure that our old 4300 did - but I can say for sure - it was
> on a room UPS that had 3 hours capacity backed up by an autostart
> generator.
>
> I don't think that we ever had an unscheduled power outage...
>
> Villy

I got this from the Running VAX/VMS Under Linux Using SIMH guide by
Phillip Wherry (http://www.wherry.com/gadgets/retrocomputing/vax-simh.html).
Add this to your vax.ini:

; Uncomment the line below to enable auto-boot
dep bdr 0

>From the guide:
First, the line: dep bdr 0 is used to deposit the value 0 in the BDR
register. This register contains the boot jumper/switch flag used by
the VAX console ROM code. If bit 7 is high (i.e. if we'd instead said
"dep bdr 80"), the ROM will print the VAX console prompt (>>>) instead
of autobooting. For those who remember the VAX 11/7xx series machines,
setting BDR to 0 is the equivalent of setting the key switch to the
DISABLE position; setting BDR to 80 [hex] is like turning the key
switch to its ENABLE position.

Hope this helps,
Tim