DSQD Drives (Was: RE: Diags/Boot image for Altos 580)

From: Fred Cisin <cisin_at_xenosoft.com>
Date: Sun Mar 17 13:57:08 2002

On Sun, 17 Mar 2002, Doc wrote:
> So, this means I can make disks from image with a vanilla 5.25 1.2M
> drive, on a Linux box, right? Assuming I have DSDD floppies and use the
> correct device (/dev/fd0D720) with dd?
Maybe. Does that driver successfully switch step independent of switching
density?
If so, it might work IFF it happens to be the same number of bytes per
sector and sectors per track. It might be, but I'm not going to get a
chance to look that up today.

> Alternatively, is there any reason I couldn't temporarily move the
> drive itself to a PC to build the disks?
With the right software,.. certainly.
For use in a PC with the stock PC cable, rejumper the drive to the second
drive select position (DS1 of 0/1/2, 2 of 1/2/3, B of A/B/C)
Lie to the CMOS and tell the PC that it is a 3.5" 720K.
You can test the drive then by putting a blank virgin 360K floppy in it
and formatting it as a 720K. (Note: a few people (Tony) have had
reliability problems using 360K blank diskettes as 720K, even though they
are spec'ed the same. It might be due to closer proximity to the
Greenwich meridian :-)
Received on Sun Mar 17 2002 - 13:57:08 GMT