Vincent Joguin wrote:
> "Michael J. Mahon" <mjmahon@aol.com> wrote in message news:<4KudnQFGkf0D6tDfRVn-vQ@comcast.com>...
> 
>>>He heeh, yes I agree - but if the current disk formats don't hold enough
>>>information about the disk formatting (for protected disks), then we may
>>>have no option.
>>
>>But the FDI format does not store "sufficient" information for all
>>protection methods, either.  In particular "soft bits" must be detected
>>and that requires multiple reads and bit comparisons.  This is _not_
>>a simple problem of "recording" what's read from the disk, since the
>>read mechanism can be a source of "data" as well.
>>
> 
> 
> The FDI format *does* store sufficient information for all protection
> methods.
> Each track is read about 50 times, then stored to a statistic-oriented
> format (you can read the FDISPEC.TXT file from the Disk2FDI archive
> for more information).
> 
> If you are talking about "unstable" bits caused by the floppy disk
> controller of the Apple 2 (more specifically its PLL), this is a
> matter of emulation, not of imaging. Hence why I said a good floppy
> disk drive emulation is not an easy task.

After reading the FDI spec, I agree--the low-level streams contain
enough information to allow a complete emulation.

Now the question becomes whether a critical mass of interest will
cause the confluence of 1) an accurate emulation, and 2) a suitable
assortment of FDI images of protected software.

Good luck!

-michael

New Applesoft BASIC interface for NadaNet networking!
Home page:  http://members.aol.com/MJMahon/