Strange Teledisk question

[Chuck Guzis]

On 06/23/2018 04:53 PM, Fred Cisin via cctalk wrote:

> I had hoped that Chuck would have an answer.
> 
> If you have two disks that are nominally the same, and one works and the
> other doesn't, then there is obviously something different.
> 
> If the sector contents are the same, then the next step would be to
> examine the headers, gaps, and addressmarks.
> 
> For example,
> if the gap after index pulse, before the first sector ofeach track is
> too short, then it may not be able to read the sector header of the
> first sector.  (A serious and common problem with NEC-style FDC, not
> usually a prolem with WD-style FDC)
> 
> Do you have a way to examine the raw track encoding?
> I used a track read with a WD 179x (slightly modified "Trakcess" on
> TRS80 Model 3), and "TE" with the Central Point Option Board.

Find a copy of Anadisk and see what it reports regarding sector
ordering.  Also, you might try "sector" mode with the "Diagnostic Read"
function, though that requires a bit of knowledge.

Another thing to try is to grab a copy of Dave Dunfield's ImageDisk
utility and see if it gets the copy right.  You could also image both
disks and compare the images.

TeleDisk has a lot of "special case" code.

People still have diskette drives?

--Chuck