15 Jun
2016
15 Jun
'16
1:45 p.m.
On Wed, 15 Jun 2016, ethan at 757.org wrote:
I'm not sure if it has anything to do with it, but
over on the early SGI
and Sun and NeXT stuff you had to change the block size on the CD-ROM to
get them to work.
Yeah, I think you mean the 2048 vs 512 byte block size. SGI's use a 512
byte size, IIRC. Folks were just talking about that a few weeks back, in
fact.
The early Toshiba drives had solder pads that could be
split open or
re-closed to change block sizes and such to get them to work on all of
the different hardware types.
Most SCSI-based Yamaha and Pioneer drives have a jumper you can set for
it. However, I tried this with my Pioneer SCSI CDROM and it still didn't
work. I guess if nobody knows I can figure out how to run a
debugger/syscall-profiler of some kind on MacOS 8.1 and fire up Disk Setup
and see what it's actually looking for. My guess is it's just checking to
make sure the SCSI vendor ID is "Apple" and then happily goes on with it's
job. However, I just don't know for sure yet.
I also don't know if altering a ROM image like that would have disastrous
effects if, for example, the ROM image is appended with a CRC32 checksum
that will fail once I flash it with a hacked image. I also am not sure if
I can find the right spot in the firmware image to do the byte-patch. Lots
of unknowns, so that's why I'm seeking the advice.
-Swift