Reading Mac disks in PC

David F. Spencer dspencer at
Wed Feb 25 15:21:20 EST 1998

In article <EoJI02.J2K at>, bobf at PROBLEM_WITH_INEWS_GATEWAY_FILE (Bob
Funchess) wrote:

> > >>Does anyone know of freeware for reading Mac disks in PC?
> > >
> > >If you are talking about old information that was already written on
> > >Mac-formatted disks, the easiest is to use a Mac to read them and then
> > >rewrite the same information on PC-formatted disks.
> > This is the solution often offered and of no use if the user has a Mac
> > formatted disc containing data and only a PC to hand.
> > Try searching for mac and disk.
> Conversion programs for the PC will help if it's a high density (1.44M)
> disk.  If you've got an older double density (400K or 800K) disk, you'll
> need to find a Mac somewhere, since PC drive hardware isn't capable of
> dealing with those formats (double density 3.5" PC disks are 720K).

To clarify that last statement a bit, the drive per se is not the major
problem but rather the floppy drive controller chip.  Central Point
Software (the PC Tools folks) used to sell a piece of hardware called the
Deluxe Option Board which was installed in an ISA slot, with the floppy
drive ribbon cable running to this board first, then the drives were
connected to the DOB.  Using supplied software you could read the Mac 800K
diskette format, copy to PC disks, etc.  The board actually allowed you
(with CPS utilities) to see literally every byte on a floppy disk and
permitted the lowest possible level of disk editing. As far as I know the
DOB was never updated to handle 1.2 meg (HD 5.25) or 1.44 (HD 3.5) disks
and I assume hasn't been available for many years now.  (I bought that card
in about 1990 so I could read Mac floppies on my PC).

It is true that there isn't (and can't be) any software that reads Mac 800K
diskettes on a PC. The 1.4 meg (HD) drive was introduced on Macs 8 or 9
years ago but of course Macs can still read, write and format 800K
(although not 400K) disks so if you have one of those then you're out of
luck if you can't find a Mac.


David F. Spencer, PhD
Dept. Of Biochemistry
Dalhousie University
Halifax, Nova Scotia

dspencer at
dspencer at

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