Tandem BSC non autoboot controller

[amiman99]

It's been a while, but in A2000 with supra 2000 SCSI controller that did not autoboot for me, I used the boot disk "SupraBoot" from http://amiga.resource.cx/exp/search.pl?product=&company=supra&amiga=2000&intf=&cat=scsi&mid=&base=dec&pid=#s_wordsync
You can look at the startup-sequence to get some clues how they do it.
It's mostly assigns after the HD is recognized.