[Coco] Warning about 3.5" disk failure

[Mike Pepe]

Bob,

> Since both the PC and the Coco use the index as the sync for a start of 
> track, and the index is produced in the mechanism of the drive, altering 
> the relationship between the drive and the disk, means that the disk 
> becomes unreadable.

As I recall, I've covered the index hole on floppies lots of times. It 
does not affect reading or writing. Our drives our soft-sectored, the 
start of the track is determined by reading the track's data, and the 
index pulse has nothing to do with the actual reading and writing of the 
data.

It does affect formatting. You absolutely cannot format a disk unless 
the index is present.

Give it a shot, try some opaque tape over the index hole on a 5.25 
incher and see if the disk can be read. If not, my brain is faulty and 
it must be something else I'm thinking of.

-Mike