Qbus split I&D?

[Roe Peterson]

On Mar 16, 2015, at 7:58 AM, Noel Chiappa <jnc at mercury.lcs.mit.edu> wrote:

>> From: Pete Turnbull
> 
>> 2.9BSD doesn't need split I&D, but 2.11BSD does.
> 
> Doesn't 2.11 also need Supervisor mode (at least, for the networking code)?

Yep.  Netnix runs as a standalone task in supervisor mode.

> 
> Of course, there is not (AFAICR) any machine with split I&D but not
> Supervisor, so the question above is purely intellectual, not of practical
> consequence.


Nothing wrong with purely intellectual questions.

> (Unless you have an 11/xx with an Able ENABLE board! :-)

What is an ENABLE board?  Unibus, qbus?


> 
>    Noel