On 4/10/07, David Betz <dbetz at xlisper.com>
Thanks again! I have now successfully installed a
minimal RT-11 on
the RD54 of my PDP-11/73 system and it boots! Now I just have to
configure it with the programs I need (like DECUS C).
I guess RT-11 uses 512 byte blocks. My RD54 says
it holds around 64k
blocks. That's about 32mb.
That's the first partition.
What happened to the rest of the 150mb RD54?
It's still there, lurking.
Is it possible to put more than one partition on
the drive or
to convince RT-11 to use more than 32mb of the disk?
RT-11 uses, IIRC, 16-bit block pointers... 65536 x 512 bytes == 32MB,
the largest swath of a big drive it can grab in one chunk. I've never
personally run RT-11 with a disk over 32MB, so I don't know how it's
done, but I know it can be done. It might or might not depend on what
version of RT-11 you have. I *think* if you have MSCP support, you
always have the ability to have multiple partitions on your large
drives, but someone with experience on new(ish) hardware should chime
in. The largest machine I ever ran at home was an 11/23 with a couple
of RL drives. When I did use RT-11 on an 11/73 with a large disk, it
was under TSX-11, and without the docs in front of me, I'd hesitate to
quote technique from memory.
You have to use the LD driver. Myself I use a smaller drive as 32mb for
RT-11 is a very roomy disk. A Quantum D540(rd52) at 32mb is perfect, they
are also cooler and far more reliable. Another good choice is an St225
(rd31) at 20mb it's still large for a RT-11 system.
You should be able to find what you are looking for in
the RT-11 docs
for versions of RT-11 > 5.4, at least. Dunno about < 5.4.