Very cool project max1zzz! I'll be watching that thread too.
I know you're satisfied with 8.6, but this whole mystery of the floppy support piqued my interest. I did some more digging and I think I see what happened. I decompressed several versions of the Mac OS ROM file (thanks to the SheepShaver source code)--1.1.2, 1.1.5, and 1.2. Starting with version 1.2, they removed the .Sony and .MFMFloppy DRVRs from the Mac OS ROM file. I still see their names referenced in places, but the actual DRVRs are no longer there. It didn't affect earlier machines with floppy drives because they use their built-in ROM which still has the floppy drivers, but it definitely affected the iMac.
It does kind of raise the question...would it be possible to bring support back to newer Mac OS versions by adding an extension that installs the .Sony and .MFMFloppy DRVRs on New World machines? The other possibility might be to patch the very newest Mac OS ROM file to include those drivers. Unfortunately, I am not well-versed in classic Mac driver voodoo, but I have to believe it's possible.
I know you're satisfied with 8.6, but this whole mystery of the floppy support piqued my interest. I did some more digging and I think I see what happened. I decompressed several versions of the Mac OS ROM file (thanks to the SheepShaver source code)--1.1.2, 1.1.5, and 1.2. Starting with version 1.2, they removed the .Sony and .MFMFloppy DRVRs from the Mac OS ROM file. I still see their names referenced in places, but the actual DRVRs are no longer there. It didn't affect earlier machines with floppy drives because they use their built-in ROM which still has the floppy drivers, but it definitely affected the iMac.
It does kind of raise the question...would it be possible to bring support back to newer Mac OS versions by adding an extension that installs the .Sony and .MFMFloppy DRVRs on New World machines? The other possibility might be to patch the very newest Mac OS ROM file to include those drivers. Unfortunately, I am not well-versed in classic Mac driver voodoo, but I have to believe it's possible.