When mixing narrow and wide devices you must only use the first eight
scsi ids. If you don't, scsi arbitration will not work correctly. The
scsi bus uses the data bits to arbitrate for the bus. A narrow device
does not see the upper eight arbitration bits and can fowl things up.
Your wide devices can still work in wide mode, but their addresses
should be set between 0 and 7 where the narrow devices can see them for
arbitration.
Other thoughts:
The Scsi arbitration priority is ordered as follows:
7,6,5,4,3,2,1,0,15,14,13,12,11,10,9,8, where 7 is granted the bus first.
This is one reason why many host adapter's id are set to 7. The other
reason is for a typical 0,1,... scan order. It might make sense to scan
from 7,6..0,15,14,..8 to make the more important devices first in the
device list.
<>< Lance.
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