[Coco] Formatting HD floppies w/ modified controller.

[Gene Heskett]

On Friday 07 October 2005 20:42, Robert Gault wrote:
>OK, just in case it might make a difference, I told format to use 135
>TPI and 80 tracks for the 3.5" disk. With the current v3.02.05 that
>means dmode dns=7, typ=21, and cyl=50. Format ran to completion with no
>errors creating $B40 sectors.
>
>I don't believe I have any way of actually determining the track density
>of a disk. Someone can let me know if there is readily available
>software that can do this, not just report a header value.

Dyson used to make a standard test disk, but I haven't seen one of them
puppies in 20 years, Robert.  It was also quite pricey, about 100 bucks. 
Made for the servicers of the drives, it contained tracks with such
things as azimuth wobble, tracks with lots of noise in the guard bands,
that sort of thing.  You could align a 40 track drive to an accuracy in
the micron range with it.  The one I saw was for 40 track (48 tpi) drives,
and I'd assume they also made one for the 80 track (96 tpi) stuff, but I
never had the pleasure of seeing one of those.

The biggest downfall for Dysons potential market was that you absolutely
couldn't convince the techs of the day that it couldn't be copied.  They
had no concept of the requirements of the drive that actually made that
disk, and I've seen techs trying to use copies and wondering why they
weren't seeing the stuff on the scope that the original disk could do.

-- 
Cheers, Gene
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
99.35% setiathome rank, not too shabby for a WV hillbilly
Yahoo.com and AOL/TW attorneys please note, additions to the above
message by Gene Heskett are:
Copyright 2005 by Maurice Eugene Heskett, all rights reserved.