Re: Hardware musings

["Michael J. Mahon" <mjmahon@aol.com>]

Andy McFadden wrote:
> Charlie <charlieDOTd@vereyezon.net> wrote:
>
> > > I wonder why that is... maybe the index hole, the pc drive relies on the 
> > > index to pass?
> >
> > Yes at least it needs the index pulse with Disk2FDI although I don't know if 
> > it is really used to do anything other than get the process started. 
> > Disk2FDI uses some pretty interesting tricks to get an MFM drive to read GCR 
> > disks.
>
>
> The signal from the index hole is one of the streams recorded in the .FDI.
>
> I haven't looked at the code in a while, but I believe it's used to find
> the start and length of the track.

That's a good way to handle it.

But a PC floppy controller--and maybe the drive itself--requires a
stream of index pulses just to believe that a floppy is inserted.

-michael

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