RL02 version of UNIX6?
billdegnan at gmail.com
Fri Feb 3 15:03:08 CST 2017
> > 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.
OK. Hopefully I can repair my EIS board then. Otherwise it's RT-11.
More information about the cctech