Re: 800k floppy on a Mac Classic II to transfer files to IIgs

[Greg Buchner <null@none.invalid>]

In article <1i5rott.1u0j73tk7d0pqN%dempson@actrix.gen.nz>,
 dempson@actrix.gen.nz (David Empson) wrote:

> Tristan Mumford <xtristan.xmumford@xgmail.xcom> wrote:
> 
> > The Classic seems to do a fair job of making floppies. I can't vouch for the
> > classic II though. As it has been said though, formatting on the IIgs first
> > does make a difference.
> 
> Regarding the formatting issue: there are two potential problems.
> 
> If you use a Mac which is "too new" to format the disk, its drive is not
> a real SuperDrive. Later Macs switched from the Sony mechanism used in
> the original SuperDrive to a cheaper one (made by Mitsubishi?). The way
> to tell them apart is whether the drive will "grab" a disk and pull it
> in when you insert it. If you have to manually push it all the way in,
> it is the newer/cheaper type, not a Sony SuperDrive.
> 
> The newer drive is not as accurate as the old one for handling the
> variable rotation speed used on the 400K and 800K GCR formats, so if you
> a format a 400K/800K disk in one of these drives, it may not work
> reliably. No problem for 720K or 1440K MFM formats, which use fixed
> rotation speed, but they need a SuperDrive and SuperDrive card on the
> IIgs. The newer drives can read 400K/800K well enough, and seem to be OK
> for writing as long as the disk was formatted in an older drive.

FWIW, the newer model Superdrive in my Quadra 650 writes 800K ProDOS 
disks that the drives hooked up to my IIGS read just fine.  This has 
been with preformatted 720K MS-DOS disks.  Same couldn't be said of the 
drive in my PowerMac 7500, which I seem to recall looks exactly the same.

Greg B.

-- 
Actual e-mail address is gregbuchner and I'm located at gmail.com