[Simh] VAX 11/782 simulation [was: :Re: Pdp8 terminals]

[Hittner, David T (IS)]

Wasn't the VAX 11/782 and the Asymmetric model de-supported at some point during the life of VMS?

I seem to remember hearing (at a DECUS Symposium?) that existing 11/782 customers would have to separate them into two 11/780's and then cluster them to upgrade to the latest version of VMS.

Dave


-----Original Message-----
From: Simh [mailto:simh-bounces at trailing-edge.com] On Behalf Of Johnny Billquist
Sent: Wednesday, September 07, 2016 2:55 PM
To: Ray Jewhurst
Cc: simh at trailing-edge.com
Subject: EXT :Re: [Simh] Pdp8 terminals

Hi.

On 2016-09-07 19:00, Ray Jewhurst wrote:
> My apologies. To be honest I am very ignorant about of the science of 
> computers. I am disabled, cannot work but I am a total computer 
> history buff. I want to learn and know and experience as much as I can 
> and Simh is a major part of that. I  want to help where I can so 
> please excuse my occasionally confusion.

No worries. You never learn if you are afraid of making mistakes. 
However, if you are not rather experienced writing code, I think that implementing something like the VAX-11/782 might be quite a task... Not to mention that I don't know where you'd find a version of VMS that would support the machine.

Maybe find something a little simpler to start with? Like the talk about expanding the PDP-8 to more generic support for devices than the current implementation.

	Johnny

>
>
> On Sep 7, 2016 12:46 PM, "Johnny Billquist" <bqt at softjar.se 
> <mailto:bqt at softjar.se>> wrote:
>
>     The 11/782 are no more asynchronous than any multiprocessor system.
>
>     The A in ASMP stands for assymetric. As in, the second processor did
>     not run any kernel code, but is a slave processor to the primary
>     processor. It gets scheduled with user-land code to run, but any
>     trapping to the OS means it interrupts the main processor, who do
>     all the work.
>
>             Johnny
>
>     On 2016-09-07 18:23, Ray Jewhurst wrote:
>
>         I think you are like I am. I would like to see every DEC simulator
>         possible. Right now I am doing some preliminary research into the
>         feasibility of a VAX 11/782 which is an asynchronous dual processor
>         11/780.  I will need help because I am not a real experienced coder.
>
>