ProDOS 32MB limit?

[mkelsey@eecs.wsu.edu (Michael Kelsey (Journey finatic))]

For over two years now I have been heavily involved in the PC market, dis-
banding my Apple II usage when my ColorMonitor //e failed to turn on one
day.

Over this period I have acquired numerous hard drives ranging in size from
40MB to 100MB, all SCSI by nature.  The SCSI interface inside my Apple II
is an off-brand AEC low-cost solution that has the ability to recognize
a single hard drive as one two partitions, but nothing more despite the
hard drive size.  It will also recognize two separate hard drives, peaking
at 32MB per drive.

Effectively, I lose space when connecting a 100MB SCSI drive versus a 60MB
drive, imposed by the limitations of ProDOS.  The software provided with
the controller recognizes the size of the hard drive even though it spans
well above the 32MB limit. 

Knowing most SCSI controllers support up to seven devices, I have to wonder
if this controller physically supports this many devices, and if it would
be possible to directly register access the controller as opposed to using
the ROM block access.

Would a rewrite of the the ProDOS block routines help overcome this 32MB
limitation on an Apple //e?

Could a device driver be implemented to map more than two hard drives
to an unused slot? (i.e. slot 5 or slot 4?)  Would ProDOS detect a 
device driver conflict between the mouse I/O and the disk I/O if a
physical drive was mapped logically to slot 4?

Is there any means to discern whether the controller actually supports
more then two devices, i.e. a chipset to scrutinize?

It would appear the 32MB limitations are imposed by the operating system
seeing how block numbers may only be specified by a 16-bit number.

Has anyone else considered this thought, or researched this topic?

Thank you in advance!

/\/\ichael |<elsey
mkelsey@eecs.wsu.edu