20 Jan
2023
20 Jan
'23
1:13 a.m.
On Jan 19, 2023, at 6:03 PM, Jim Brain via cctalk
<cctalk(a)classiccmp.org> wrote:
On 1/19/2023 3:38 PM, Paul Koning via cctalk wrote:
I see it as seeking out the community. Your point probably is about casting a
wider net to individuals, but I think asking an organization to help creates more comfort,
especially if you're talking about irreplaceable data like this. Given the age of the
disk and the expectation for errors, even if a single community member had been asked, I
doubt they would try to read it from Linux or similar. It's an option, yes, but not a
recommended one, since you might have limited reads available, and a flux read gives you
maximum data with minimum effort.
True. But if it is known to be a DEC (RX50) disk, reading it from Linux is a well known
standard thing to do. I have been doing it for more than 20 years, with RSTSFLX (writing,
too). Standard PC floppies have no trouble at all, you just have to set the mode to 10
sectors per track.
Earlier still I did the same in DOS, using INT13 programming under djgcc.
My point here is that the community is substantial and contains vast expertise on many
details of old machinery. So my guess is that an email to the list saying "hey, I
need to recover the contents of files on an RSX RX50 floppy, what is the easiest and most
reliable way to do that" would have produced several high quality anwers in a matter
of hours.
On Jan 19, 2023, at 4:31 PM, rar--- via cctalk
<cctalk(a)classiccmp.org> wrote:
Museum Staff Helps Exonerate David Veney
January 19, 2023, Hunt Valley, MD — Staff members of the System Source Computer Museum
recently completed a project that helped exonerate David Veney, wrongly convicted of rape
in 1997. In 2005, after Mr. Veney sought a new trial, the state found irregularities in
the prosecution, released Mr. Veney from prison, and declined to re-prosecute. ...
Wow. That is a marvelous story.
Just one comment: using the GreaseWeazle makes sense here, but other options would
include seeking out the help of the community. For example, 5.25 inch floppy drives are
widely available, and reading RX50 format on an ordinary drive in Linux is a trivial
exercise. Similarly, feeding the recovered device image to a SIMH instance would be easy
enough. The tricky task of translating the application data to readable text still
remains in any of those approaches, of course.
paul
Your SIMH thought makes a ton of sense. Not knowing
the effort here, I would assume once the flux image was available and with the lack of SW
to do much with the data available anyway, treating it like a raw data dump was probably
the most expedient option to get to the end goal.
I was thinking that having the OS interpret the file structure would take that part of
complexity away. At that point you're still left with the question of the application
data format, but details of on disk structure are covered this way.
paul
Jim
--
Jim Brain
brain(a)jbrain.com
www.jbrain.com