Roger Smith <ACPS5788@Ryerson.CA> (02/27/91)
Hi,
I was wondering if anyone has information on How to read I.B.M Dos Disks or
AMIGA disks in an apple HD disk drive. I am thinking about writing a utility
similar to Apple File Exchange that would allow you to stick in an AMIGA disk
and copy files back and forth.
I discovered that amiga Floppies use MFM encoding and is similar to the format
used for IBM formatted floppies.
The FDHD (1.44MB) Drives include the capability to read and Write MFM
and GCR floppies . I think these routines are part of the File or Disk
Manager Routines.
Is this a pratical project? Why has there been no emphasis on reading other
disk formats besides DOS?
Any input on the subject would be appreciated.
Thanks Roger Smith
Ryerson Polytechnic
Ont. Canadajnmoyne@lbl.gov (Jean-Noel MOYNE) (03/02/91)
AmigaDOS and MS/Dos file-formats are quite differents, but
depending on what Apple's disk drive can do, it might be possible to read
Amiga disks off an Apple HD disk.
But for the moment they are other ways to transfer files between
the two machines: you can write very easily (no hardware required) MS/Dos
disks on an Amiga (720 Ko 3.5' format disks), and if you own AMax (the
Amiga Mac emulator) you can hook up a Mac drive to the Amiga, and write
Mac 800k disks.
Amiga's disk format has nothing special: 80 cylinders, 9
sectors/track. The only big difference with IBM disks is that there's no
gap between sectors, but only one gap at the beginning of the track, then
all the sectors stick together. If your drive can cope with that, then it
could be possible. But I'm not a disk specialist.
JNM
--
These are my own ideas (not LBL's)stevec@Apple.COM (Steve Christensen) (03/02/91)
ACPS5788@Ryerson.CA (Roger Smith) writes: > I was wondering if anyone has information on How to read I.B.M Dos Disks or > AMIGA disks in an apple HD disk drive. I am thinking about writing a utility >similar to Apple File Exchange that would allow you to stick in an AMIGA disk >and copy files back and forth. Reading DOS disks is easy: just ask the floppy driver to read the blocks from the disk. The more interesting part is interpreting what's on the disk so you know where all the files are. That's what Apple File Exchange does. > I discovered that amiga Floppies use MFM encoding and is similar to the format > used for IBM formatted floppies. Well, Amiga and DOS floppies both use MFM encoding, but as I understand it, the track formats are vastly different. > The FDHD (1.44MB) Drives include the capability to read and Write MFM >and GCR floppies . I think these routines are part of the File or Disk >Manager Routines. No, they're part of the floppy disk driver. Just as you could read/write GCR disks in the pre-FDHD drives, you can read/write both GCR and MFM with the FDHD drives (and associated hardware in the Mac). > Is this a pratical project? Why has there been no emphasis on reading other > disk formats besides DOS? Reading different disk formats gets to be an interesting task since you have to deal with different numbers of sectors per track, different sector sizes, different encodings. I would think that the reason support for DOS disks was added (and not others) is that DOS disks make up a high percentage of the 3.5" disks out there. steve -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Steve Christensen Never hit a man with glasses. stevec@apple.com Hit him with a baseball bat.