RL02 version of UNIX6?

[william degnan]

>
>
> >>
> >>
> > So you're saying for a system with a MMU but no working EIS (removed for
> > now) and 64KW RAM (half populated M7891) you're suggesting which OS?  I
> > still have to research the best options, RSX-11M?
>
> I'm not sure there is one.  DEC OS designers typically would assume that
> they are dealing with non-broken systems.  Systems with MMU all have EIS,
> so an OS that requires an MMU would typically take advantage of EIS
> instructions.  That's the case in RSTS/E, for example.
>
> OSs designed for non-MMU systems would also typically assume no EIS,
> because they were intended for the entire PDP-11 family including 11/20 and
> the like.
>
> In other words, if you don't have an EIS that works, you're likely to be
> limited to no-MMU systems because those are likely to be the only ones
> whose authors avoided EIS instructions.
>
> There may be some mixed cases, an OS where the same basic system can be
> built for no-MMU as well as MMU configs.  If so, there might be a way to
> build an MMU=yes, EIS=no config.  Or it may come with EIS=no by default
> because some of its configs have to handle that and it's easier to do it
> consistenly.  Possibly RSX is such an OS; I don't know.
>
>         paul
>
>
>
OK.  Hopefully I can repair my EIS board then.  Otherwise it's RT-11.
b