[BBC-Micro] Hard or Soft Sectored Drives

Pete Turnbull pete at dunnington.plus.com
Fri Dec 22 10:29:28 GMT 2006

On 22/12/2006 09:21, David Harper wrote:

> One can only guess here. I would suspect that Superform may format a whole 
> track at a time (as modern formatting programs do) if soft sectors are used. 
> Thus there is a single formatting action per track, possibly with no option 
> as to how many sectors are included. On the other hand, if the sectors are 
> hard then each sector will have to be formatted separately, waiting for the 
> index pulse each time, and so a sector counter will be needed.

Superform tries to tell the drive controller to use 17 sectors per track 
(IIRC) on soft-sectored disks, ie those where the controller in the disk 
allows raw track access or allows a Mode Select to change the number. 
On hard-sectored disks, I expect (but haven't looked at it for a while) 
it asks the drive how many sectors there are; this is typically not 
changeable on small hard disks (or if it is, it's just a function of 
whether the sectors are 256 bytes or 512).  The formatting is always 
done by a Format Track command.


Pete						Peter Turnbull
						Network Manager
						University of York

More information about the bbc-micro mailing list