Substituting DSHD for DSDD disks (or DS2D if you prefer)

Chuck Guzis cclist at
Sun Oct 25 23:44:04 CDT 2015

On 10/25/2015 09:19 PM, Eric Christopherson wrote:

> Also, do I always need to cover one hole on a 3.5" HD disk when using
> it in an HD-capable drive? Or does the disk or the OS notice it's
> been formatted as DD and then treat it accordingly?

In *most* applications, the extra hole in the HD floppy changes the 
operating parameters of the drive itself. (There are exceptions, notably 
on some IBM systems of the PS/2 variety).

Of course, on a DD-only drive, the drive is blind to the extra hole. 
One of the things you have to keep on eye peeled for when handling a 
bunch of 3.5" floppies--to read the disk on an HD drive, you need to 
cover the hole.


More information about the cctalk mailing list