On Thu, Jan 23, 2014 at 5:50 PM, William Donzelli <wdonzelli at gmail.com> wrote:
It looks like I might have an extra RK05j available,
but first, a question:
I do not need another RK05J, but I will take a stab at your question...
Can a reasonable PDP-11/45 system be made using a
single RK05?
It's entirely dependent on your desired OS. I don't know how far back
one might go to find a suitably small RSTS version that fits in 2.5MB,
but many (most?) versions of RT-11 will fit in that much space, and
compared to a floppy install, an RK05-based RT-11 system will feel
quite zippy.
In the 1980s, we ran multi-user RSTS and RSX-11/M systems on a single
RL02 and in the same timeframe, I was running RT-11 on a single RL01
with lots of free space. It might be a "waste" of the resources of an
11/45 to run RT-11, but it will surely work.
If you have decided on what OS you would like to run on the 11/45, see
if you can find the SPD for it. That flyer will contain, among many
other facts, the minimally-supported disk configuration. You can
often squeeze things tighter than the SPD indicates (trimming
libraries, help files, less-common-used utilities, etc), but it's
likely that a vanilla install would fail if you try to undersize the
recommendations.
If I wanted to run a box with a single RK05, I'd also want removable
media, something other than the boot disk: RX floppies, TU58 tapes...
something, real or emulated, just to be able to migrate programs and
data on/off the machine. With enough RAM to run vtserver, it's not as
critical - you can keep RK05 images on a modern machine and dump/blow
your images from/to the same pack over and over.
-ethan