Initio INI-9100UW - Manual (Page 109)

12-5
SCO UNIX can not support different head mappings for each disk drive under
the same host adapter. The head mapping will be based on the setting
represented by target ID 0.
Drives with Multiple Operating Systems.
It is mandatory that the same head mapping be used across multiple operating
systems on one drive. However you can use different head mappings on
different drives with the exception of SCO UNIX. It is recommended that you
enable "DOS Space > 1GB" option if the capacity of your SCSI hard disk has
more than 1 GByte.