Mac Plus floppy interface

["Simon Biber" <simon@basilisk2.cjb.net>]

This is continuing on from a topic below...

I tried plugging my Apple 5.25" drive which works fine on a platinum IIe
into the drive expansion connector on the Mac Plus.

With it connected, the Mac sits at the flashing question mark while checking
for a disk in both the internal 3.5" and external 5.25" drives. Yes, the
light on the 5.25" drive flashes on and off, and it is looking for a disk to
start up off.

It's interesting that it doesn't try to boot off the hard disk when I have
the 5.25" drive connected, but just sits there checking each drive.

I then turned it off, removed the 5.25" drive, and restarted it, and it
booted off the hard disk immediately, no problems encountered.

Then I put the drive back in and started off a 3.5" floppy since it wouldn't
start from the hard disk with it in. The Mac desktop came up, then it tried
to read off the 5.25" drive. I get a "This disk is unreadable: Do you want
to initialize it? (Eject) (Initialize)" box. I attempted to initialise a
disk, it tried to do something on the drive, then said Initialise failed. I
say Eject, but the drive can't eject! So it just finds the disk again and
repeats the "This disk is unreadable" message, in an infinite loop.

It seems quite promising; is writing a driver to support this drive
feasible?

I wonder if it is possible to read a ProDOS disk from that drive on the Mac.
I also wonder if it is possible to format a 5.25" disk as a Mac disk on that
drive.

Simon.