Re: Apple II 3.5" Controller and SuperDrive problems...

[shack@onyx.southwind.net (Randy Shackelford)]

mkelsey@spam.eecs.wsu.edu wrote:

: I'm just guessing at this, but I believe that the mainboard on the inside
: of the drive housing is actually a bridge between the 800K or SuperDrive
: to enable drive eject and designate the drive as an Apple II viable
: drive.  Again, this is just a theory that I hope to prove correct 
: later on.

Yep, the daisychain logic board works the in use light and eject button,
allows daisychaining, and lets a IIgs and //c plus recognize it. Take it
out and you have the beige 800K essentially.

: One thing that Apple II 3.5" Drive controller states in the manual is
: that it is equipped with a 6502 and the SIWM chipset.  The Macintosh
: (older models) had at least the SIWM chipset on board.  Granted, the
: operating system handled disk inject/eject sequences, but it leads me
: to believe that in all reality, the mainboard underlying the drive in
: the IIgs housing is a "friendly" interface designed to facilitate older
: equipment.

Don't forget a 14 MHz oscillator which the SWIM needs to function.

: That would make me think that the Apple II Desktop would treat the disks
: just as it treats my QRAM //e volume, with a "hard drive" icon.  Instead
: it places a 3.5" icon for any of the disks.  Perhaps Apple II Desktop
: identifies the controller as a smart port, but doesn't know quite what
: to do beyond that.  I know for a fact that Apple II Desktop on a IIgs
: would eject the disks when dragged onto the trash.  Therefore, it leads
: me to believe that Apple II 3.5" Drive controller is identified as a
: smart port, but not as a smart port that Apple II Desktop recognizes.

Apple II Desktop uses a primitive, no longer supported device identification
process, namely the device ID nibble for each device in the device list.
Change the value for a device and you change the icon that appears.

: The only way I have found to format 720K disks on my //e is to take a
: blank MS-DOS 720K disk, copy blocks over from any other ProDOS volume
: to make an identifiable "ProDOS" volume, and then erase (not format)
: the volume with Copy II+.  Somehow when Copy II+ erases the disk, it
: queries the device as to the size and writes the appropriate table.
: Note that an erase of the disks will only erase the first few blocks
: on the disk and leaves the remaining sectors unscathed.

I wrote a program which writes a ProDOS directory and bit map to any disk
which can physically be written to. I call it a pseudoformat. Never tried
it on a 720K, I'll give it a try next time I have the IIgs on.
--
Offsite mail to this host gets nuked.