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Re: My laser 128



D Finnigan <dog_cow@macgui.com> wrote:
> Bill Hicks wrote:
>> On Jan 10, 1:07�am, Michael J. Mahon <mjma...@aol.com> wrote:
>>> 
>>> Exactly. There was a short window when "single sided" disks were actually
>>> single sided.
>>> 
>>> And Apple's method of formatting is more tolerant of isolated surface
>>> imperfections than others.
>>> 
>>> -michael - NadaNet 3.1 and AppleCrate II:http://home.comcast.net/~mjmahon
>> 
>> When you init a disk does dos do any verification?
>> 
> 
> From reading some documentation on ProDOS, I got the impression that the
> ProDOS Filer utility does make an attempt at marking out bad blocks so that
> they won't be used to store data.

Nope. A disk either formats or it doesn't--there is no mechanism for
altering the track capacity. 

When formatting track 0, if it does not read back correctly, the track will
be reformatted in a different rotational phase, which can bypass isolated
media faults if they fall in sync areas. 

After a certain number of retries, it gives up. 

-michael - NadaNet 3.1 and AppleCrate II: http://home.comcast.net/~mjmahon