[HECnet] Simplest PDP-11

[Johnny Billquist]

On 2019-02-04 00:14, Brian Hechinger wrote:
> What about the different CPUs?

You can essentially group them in to a few different groups.

But for anything able to run RSX-11M-PLUS, RSTS/E and BSD, we're 
essentially talking about the 11/70 class, which includes the 11/44, 
11/70 and all J11 based machines. They are pretty similar, but I guess 
the J11 is the slightly simpler one of them, if you really want to get 
down to it.

Oh, and any Qbus machine is easier than Unibus ones.

   Johnny

> 
> On Sun, Feb 3, 2019, 17:11 Johnny Billquist <bqt at softjar.se 
> <mailto:bqt at softjar.se> wrote:
> 
>     On 2019-02-03 22:42, Brian Hechinger wrote:
>      > On Sun, Feb 3, 2019, 16:15 Johnny Billquist <bqt at softjar.se
>     <mailto:bqt at softjar.se>
>      > <mailto:bqt at softjar.se <mailto:bqt at softjar.se>> wrote:
>      >
>      >     On 2019-02-03 22:02, Brian Hechinger wrote:
>      >      > What is the simplest PDP-11 CPU/peripheral design that is
>     capable of
>      >      > running RSX-11, RSTS/E or BSD?
>      >
>      >     Define "simple" please. :-)
>      >
>      >
>      > The easiest to implement with limited tools.
> 
>     If the size of the device driver is anything to go on, then roughly
>     ranked from easiest:
>     RK11
>     TC11
>     RP11
>     RL11
> 
>     Massbus in general I think can be done to work without too much
>     complexity. RK611 shouldn't be too bad, but do add a bit more stuff.
> 
>     But I think pretty much anything except MSCP is roughly similar in
>     complexity for someone implementing it.
> 
>         Johnny
> 
>      >
>      >      > Also, what is the minimum disk space needed to install those
>      >     operating
>      >      > systems? I have a plan. Probably not a good one but I'll
>     likely
>      >     learn a
>      >      > lot in the the process so it won't be a waste of time.
>      >
>      >     RSX-11M-PLUS can run from two RL02, if you just accept the pregen
>      >     system. But that's the smallest. If you want to build stuff,
>     something
>      >     like an RK07 is required, and that is 28 Megs. But I think it's
>      >     recommended that you have two. But that probably is for more
>     reasons
>      >     than just running the actual system (it is hard to do an
>     update if you
>      >     are running on an RK07, and the update media is an RK07).
>      >
>      >     RSX-11M definitely gets away with less. RSTS/E would be
>     similar, I
>      >     think, while BSD probably wants a little more.
>      >
>      >
>      > Ok, that's what I needed to know (more ballpark than anything
>     else is fine)
>      >
>      > Thanks!!
>      >
>      > -brian
> 
> 
>     -- 
>     Johnny Billquist                  || "I'm on a bus
>                                         ||  on a psychedelic trip
>     email: bqt at softjar.se <mailto:bqt at softjar.se>             || 
>     Reading murder books
>     pdp is alive!                     ||  tryin' to stay hip" - B. Idol
> 


-- 
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