-----Original
Message-----
From: cctalk-bounces at
classiccmp.org
[mailto:cctalk-bounces at
classiccmp.org] On Behalf Of Ethan Dicks
Sent: donderdag 3 mei 2007 16:50
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: Can disks be copied using only one RL02 drive?
Henk thinks creating a RAM disk would work, and
copy files
but I don't know anything about RT-11.
That might work, but I don't think you can use RT-11 to write
the system area when fiddling packs like that. If you had a
different boot medium, floppy, say, you could treat the RL02
drive as a data volume, then it wouldn't matter. The RL02
just becomes another drive at that point.
-ethan
Charles did not tell completely what I suggested, but since
I am not sure how to do it either, I would like to know ...
I also suggested the obvious ones, get the 2nd drive connected
and do some kludge work on the READY/UNIT indicator/plug.
Since Charles' 11/23+ has 4 Mb of memory ... I remember I once
had a visitor (some 5 years go!) who showed me how to use the
extra memory (core) in my 11/35 as a "RAM disk".
I don't remember which RT11 command(s?) he used, but creating
a RAM disk is definitely possible! So, if you copy the system
files that you need to run RT11 to the RAM disk *and* you can
boot RT11 from that RAM disk, you can use the rest of the RAM
disk space to copy a few files from the RL02 disk, swap the RL02
disk and copy the files from RAM to disk, etc.
You need the RAM disk for RT11 too, because you can not simply
swap the RL02 disk, because RT11 is running from it!
Ethan did point that out.
So, here is the question I have. After creating the RAM disk,
and copying the necessary system files to the RAM disk, is it
possible to *boot* from the RAM disk, like .BOOT dev:RT11FB.SYS ?
And what would "dev" be? I also would like to know what commands
create the RAM disk
Jerome Fine replies:
I have been busy with family for the whole week.
I quick answer. The ram disk can be over 7000 blocks
and is called VM0: and uses either VM.SYS under RT11FB.SYS
or VMX.SYS under RT11XM.SYS (if you want to minimize
usage, use only one or the other). That probably leaves
more than sufficient space for an RT-11 binary distribution
if you know how to set up an LD: (logical disk). If
you don't, ask some more questions!
Basically, just INIT VM:, copy the minimum files to
VM: and BOOT VM:RT11XM - you don't need to
COPY/BOOT VM:RT11XM.SYS VM:
after which you can set up an LD:, etc. and copy the
distribution RL02 to the LD: followed by making a duplicate
back to a third scratch pack. I strongly recommend that you
don't ever write on the distribution pack.
Ask more RT-11 questions if you need additional instructions.
It really is very easy with a 4 MByte memory under RT-11 to
set up the needed VM: of a sufficient size and have only
a single RL02 drive.
Sincerely yours,
Jerome Fine
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