Re: 1571 images as G64

From: Pete Rittwage <>
Date: Wed, 29 May 2013 12:44:30 -0400 (EDT)
Message-ID: <>
On Wed, May 29, 2013 9:28 am, wrote:
> If I understand correctly the specs of the G64 format, it should be
> flexible enough to accommodate any (?) GCR based disk image data, even if
> it is signed as "GCR-1541". If that is correct then the question is - has
> anyone seen this being put into some use? Like GCR images of 1571 disks?
> Or Apple ][ (?)
> --

It's never been used for anything except single-sided Commodore disks, so
anything else would be non-standard.  It would make much more sense to
extend the header and make it G71 for 168-track double-sided disks to
prevent confusion.  However, there are less 1571 disks that have copy
protection and need GCR images than you can count on one hand, that I know

As for Apple, the specs aren't made for that. Technically, their GCR is
different than CBM- there is only one density, and the way the data is
constructed on the disk vs. what is read is odd (no sync marks per se,
every byte is a sync) AND they can have quarter-tracks.  To my knowledge,
there has never been any project to preserve original Apple floppies.

Pete Rittwage
C64 Preservation Project

       Message was sent through the cbm-hackers mailing list
Received on 2013-05-29 17:00:06

Archive generated by hypermail 2.2.0.