Originally Posted by ancalimon
I would be very interested in doing this witchcraft
So this works by inserting one end of the cable to the PC?
How do you set computers to not to reset the bus at power-on or reset?
You have both computers on the SCSI bus, they don't have to be at the ends. Though if a SCSI card has hard-wired termination which can't be disabled (I think my GVP card is like that) it would need to be at the end.
Looking at pics of the A2091 and a couple of GVP controllers, they don't seem to have any way to select the controller's SCSI ID. You'd probably have more luck choosing a SCSI card for the PC that allows its ID to be changed. The PC card might have some utility that you run to change options; Adaptec cards use a program called SCSISelect. That can also be used to disable the card's SCSI bus reset.
The SCSI FAQ
has a section about sharing the bus. Also it seems the Siamese System
from HiQ Ltd. used a shared PC-Amiga SCSI bus.
It could/should be possible to have WinUAE running on the PC, booting from a local HDF but accessing the SCSI drive as a data drive. Copy lots of files to the SCSI drive then run DiskChange on the Amiga to make it recognise the updated drive contents. And similarly in reverse. You'd have to be very careful to always use DiskChange, otherwise the partition could become corrupted.