[comp.sys.amiga.tech] Mac format disk reading/writing on the amiga

glenn@extro.ucc.su.oz (G. Geers [ext 3241]) (07/12/89)

I am posting this for a friend. I'm a PC man myself.

Does anyone know if it is possible to read/write Macintosh format disks
on the amiga without purchasing a different disk drive ?
Is the Mac drive constant angular or linear velocity ? What about the
amiga drive ?
Is there PD software to do this ? C or M2 source would do nicely.

				Thanks in advance,
							Eric

Replies to:
glenn@extro.ucc.su.oz 
please

farren@well.UUCP (Mike Farren) (08/07/89)

glenn@extro.ucc.su.oz (G. Geers [ext 3241]) writes:
>
>Does anyone know if it is possible to read/write Macintosh format disks
>on the amiga without purchasing a different disk drive ?

No.  The Mac uses a scheme, halfway between CLV and CAV, involving 
changing the disk drive rotation speed in three bands on the disk.
The Amiga cannot do this, so you're out of luck.  There are more
specific reasons why not, but this argument got out of hand some years
ago, and I don't want to go into it now.  But I point out that the
folks at Central Point Software weren't able to do it after a LOT of
work, and I tend to take that as evidence supporting my position.

-- 
Mike Farren 				     farren@well.sf.ca.usa

rachamp@mbunix.mitre.org (Richard A. Champeaux) (08/07/89)

In article <13039@well.UUCP> farren@well.UUCP (Mike Farren) writes:
>glenn@extro.ucc.su.oz (G. Geers [ext 3241]) writes:
>>
>>Does anyone know if it is possible to read/write Macintosh format disks
>>on the amiga without purchasing a different disk drive ?
>
>No.  The Mac uses a scheme, halfway between CLV and CAV, involving 
>changing the disk drive rotation speed in three bands on the disk.
>
>-- 
>Mike Farren 				     farren@well.sf.ca.usa

Why do they do that?  It doesn't seem to let them pack any more onto the
disk since they only get 800k where the amiga gets 880k.

Rich Champeaux   (rachamp@mbunix.mitre.org)

* the following are extra useless line to force rn to accept my response. *
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johnhlee@cory.Berkeley.EDU (Vince Lee) (08/10/89)

>>Does anyone know if it is possible to read/write Macintosh format disks
>>on the amiga without purchasing a different disk drive ?

On the same subject, anybody heard of a clean way to do this with an
A-MAX?  Basically, what I need is something like MAC-to-DOS, but will
work with my AMAX hardware instead of CCS's box.  Transfer disks are
not an acceptable interface.  Also, is it possible/in-the-works to
allow me to use a mac drive as an Amiga device (r/w amiga disks) again
with AMAX hardware instead of MAC2DOS?

-Vince