3 Nov
2022
3 Nov
'22
4:55 p.m.
On Nov 3, 2022, at 7:38 PM, Fred Cisin via cctalk
<cctalk(a)classiccmp.org> wrote:
On Thu, 3 Nov 2022, Paul Koning via cctalk wrote:
Exactly, and that's what I did way back when, in my original implementation of
"flx" -- a utility for accessing RSTS file systems on a PC. Later I added a
Linux way to do that, which is very much simpler -- just a matter of setting the right
mode, either with the fdprm utility or just by issuing an ioctl. My current
"flx" is written in Python, it does that automatically when it sees a floppy
being accessed.
That version includes a small script to use just the floppy access routines, to make an
image copy of an RX50 either in physical sector order or RX50 logical order. Look on
svn://akdesign.dyndns.org/flx/trunk for the code. "rx50.py" is that tool; you
can also find in "fdprm" the configuration file for the fdprm utility to tell it
about "rx50" format.
paul
An example of a non-PC format 5.25 inch disk that
normal drives can read would be the DEC RX50 floppy, which has 10 sectors per track rather
than the PC standard 9 sectors. But a standard drive will read and write those just fine,
if it's told to use that format. I did that ages ago in DOS, but in the past 15 years
or so I've only used Linux for that job. It's a simple matter, you just need to
know what the format is.
'course MS-DOS/PC-DOS/WINDOWS can't understand anything other than its own very
limited selection of formats. Does Windoze 11 still understand the original 160K format
of PC-DOS 1.00?
...
But, with a little programming, such as dropping down to BIOS level, and calling INT13h,
you can read most others that use IBM/Western Digital sector and track structures
(generally becaause they used a WD or NEC FDC)
http://www.xenosoft.com/fmts.html is a list of some of the ones that I implemented in
XenoCopy-PC