need 720k 3 1/2" disks

From: Fred Cisin <cisin_at_xenosoft.com>
Date: Mon Jun 9 23:12:01 2003

On Mon, 9 Jun 2003, jamesd wrote:
> hi
> To answer your question a true DSDD 3 1/2" drive can't read a DSHD, because
> the media is differenent... so it can't read a disk formated in a DSHD
No, a "DSDD" can't read a DSHD because it is recorded at a higher density.
WHICH IS NOT THE DIRECTION THAT WE HAVE BEEN TALKING ABOUT!

The message that you just replied to was addressing the issue of whether
the 720K diskette could be formatted in an ordinary PC (specifically XP).

EVERY DSHD drive can read "DSDD" diskettes, so long as the disk controller
supports the lower (250K) data transfer rate, and the correct
software is present. That includes every disk controller that you have
ever seen, although Tony and a few others may have some that were
originally designed for 8" that do not support the lower rates.

> drive... i can't even boot my laptop to test if the reverse is true.
> By the way i also have an excepted an offer from a fellow list member to send
> me disks... witch i really appreciate...

NO manufacturer of a 3.5" HD drive has ever made an HD drive that
couldn't ALSO handle the lower density.

Yes, the media is different. The differences are: different chemical
coating to produce a slightly higher coercivity, and an extra hole in
the diskette to tell drives which diskette it is. Those are the ONLY
differences. NOTE: not all drives include the sensor to notice the disk
differences.

THEREFORE: as stated previously, the ability to FORMAT 720K in a 1.4M is
ONLY an issue of whether the SOFTWARE supports it, and if the harware is
"normal".
Received on Mon Jun 09 2003 - 23:12:01 BST