6 Jun
2007
6 Jun
'07
4:03 p.m.
On 6 Jun 2007 at 18:17, Dave Dunfield wrote:
I also don't find ED very relevant to archiving
vintage computer diskette
images - are there any systems in need of such attention that use ED as
their standard disk format?
I do have a few IBM PS/2 distros on ED. I am aware of a few
companies selling into the PS/2 market for whom 2.88M was the
distribution medium. The Teac drive that will handles these in
either media-sense or host-specified mode is the FD-235J.
IBM used (IIRC) host-side density control on much of the PS/2 line,
so you *could* format anything from 720K to 2.88M on a plain-Jane
DS2D disk. Maybe the result wasn't entirely reliable, but it could
be done.
The "right" media is a barium ferrite formulation and has the density
aperture closer to the bottom edge of the disk than do the DSHD
diskettes. If you stick one of these things in a 1.44MB-only drive,
it appears as a DS2D.
As far as "PC drives", those Mitsubishi/NEC 360RPM drives ran MS-DOS
2.10 on their host system (the flavor is sometimes called "DOS-V").
Diskettes were generally formatted as 8x2x1024x77 or 8x2x1024x80;
some of the CP/M formats used 256-byte sectors.
Even Windows NT running on a 9801 supported that format--as does (in
read-only mode) Windows XP/2000 today. As far as Microsoft back in
the day was concerned, the 9801 platform was a PC, just not a
"Western" PC. At one time, the 9801 platform owned something like
70% of the PC market in Japan.
Hope I got this all correct.
Cheers,
Chuck