14 Mar
2003
14 Mar
'03
9:03 a.m.
--- John Allain <allain(a)panix.com> wrote:
Question: How portable are PDP11 OS'es and
software?
If I had a copy of RSX11M for the 11/23 (which I don't) could
I port it to an 11/24 and a '/34? Similarly could this RSTS be
coaxed into an 11/34?
For the machines you mentioned, the only issue is one of
device drivers. If you want to port a SYSGENed RSX system
from a Qbus to a Unibus machine, I don't know if
that would
fly. If you have distribution media for RSX-11 and your
boot device (RL02, 9track, etc.) was compatible with the
target machine, no problem at all. When I was working with
RSX-11/M and M+ (c. 1984-1993), we got our distros on either
RL02 pack or 16MT9. Our 11/34 had a TS03 and we could put
a TU80 on the 11/24 if we had to, but since one wasn't on there
normally, that's why we went with RL02.
I never did RSTS installs personally (the owner did them), but
AFAIK, it's the same deal - porting a GENed system pack from
machine to machine might cause heartburn, depending on the
exact nature of the CPU (Split I&D, no Split I&D, Unibus, Qbus,
etc.), but the distro media should be able to install on anything
of the right generation with the right devices (i.e., don't
expect to install RSX-11/M 4.0 on a machine with a UDA-50 and
an RA-90... it's just an example; I don't have any foreknowledge
that it will work or can't work).
The critical test would be to get the SPD (Software Product Document?)
doc germain to the OS in question, down the version and patch level,
and compare the hardware list with what you want to install it on. In
broad general terms, most versions of RSX or RSTS should like the
11/24 and 11/34 with varying amounts of memory (256K should be enough
for older versions; you might need more for the most recent versions).
Massbus disks (attached to an RH-11), RK05 (RK11/RKV11), RK06/RK07
(RK611), RL02 (RL11/RLV11/RLV12) or third-party controllers meant to
imitate them will be safe bets. MSCP devices are likely to not be
recognized by older versions, but should be OK for something like
RSTS v9. Again, check the SPD.
Once you have a running system, it's all about the SYSGEN. Making
massive changes in the hardware (especially the boot disk controller)
may require a new SYSGEN, depending on how parsimonous you were the
first time around. Limited support means more memory for applications,
but less flexibility when it comes to simple upgrades.
That's about all I can think of off the top of my head. I haven't
actually used a PDP-11 for anything besides RT-11 or UNIX since about
1993, so I'm sure I've forgotten or misremembered something. Also,
my experience with RSX-11 and RSTS is limited to a few versions
and a narrow range of hardware, so if I've made a mistake, I'm sure
someone will chime in to correct me. :-)
-ethan
-ethan