The boot drive normally IS at ID=0, however.
That's a real convention
throughout the SCSI usage. I don't recall ever seeing a system that would
boot, say, from ID=4. Most PC's will promote the ID=1 device to the boot
rank, but not if ID=0 is present but manlfunctioning. YMMV, of course.
Actually, both of my Mac's that I keep running here boot from
something other than ID 0. On this machine for instance, the CD-ROM
is at 0 while the main hard disk is at 1 and normally it has any
number of other items on the bus such as CD-R and scanner and
occasionally an external hard disk. I swap SCSI stuff around a lot,
testing various things, so my SCSI ID numbers rarely stay fixed for
long. My SETI machine, which is the other Mac that runs constantly,
has it's CD-ROM at 0 and it's internal hard disk at 2. I do believe
some older Mac's, and most certainly the NeXT machines, require the
boot drive to be at 0 or 1.
Jeff
--
Collector of Classic Microcomputers and Video Game Systems:
Home of the TRS-80 Model 2000 FAQ File
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