[Simh] VAX 8600: Can't boot Quasijarus (tape or disk)

[Johnny Billquist]

On 2017-09-23 01:35, Mark Pizzolato wrote:
> On Friday, September 22, 2017 at 3:55 PM, Bob Eager wrote:
>> Oh, hang on. 'boot tq0' is surely not correct. You do 'boot cpu' and then
>> specify the boot device in a console command.
> 
> Actually, neither "boot cpu" , nor "boot tq0" are meaningful commands
> with the VAX8600 simulator.  There were no "naturally" or "DEC supported"
> bootable tape devices on the original VAX 8600 system and therefore there
> is no simulation of things which never worked.  In theory, someone could
> write a tape boot program and it could be loaded into the CPU memory and
> started execution, but I don’t know of any such program.

Correct. However, yes, there were "third party" tape booting. MtXiny 
manuals have the instructions on how to boot from the distribution tape 
on a VAX 8600, for example. (It has the procedure listed for all VAX-11 
models.)

> If you followed instructions regarding how Quasijarus was originally installed
> on a VAX 8600, then it should work the same as it did on the original hardware.
> I suspect that by the time Quasijarus was put together, the MicroVAX systems
> were prime targets for system installs, and no or very little effort was put into
> getting this stuff to work on the older VAX systems.

Quasijaurus is intentioanlly supporting the old models. So I would 
suspect an 8600 would work fine. Not so sure about "newer" VAXen, though.

But essentially, if the OP get as far as the boot program loading from 
rq, then he should be able to stop it there, and get the prompt in the 
boot. And from there, he can boot from tapes, or whatever.

But I guess this boils down to a lot more of understanding both Unix on 
VAXen, and the 8600 specifically. Also, the 8600 in simh is not totally 
working like the real machine. But I think it should work well enough 
for the OP needs.

   Johnny (who still occasionally runs a real 8650.)

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