> I find 15 is typical for non-SCSI devices:

I think that 15 is what the scsipi stuff uses for ATAPI cdroms, that's where
mine are as well:
eros# cdrecord -scanbus
Cdrecord 1.10 (i386-unknown-netbsd1.5ZA) Copyright (C) 1995-2001 Jörg
Schilling
Using libscg version 'schily-0.5'
cdrecord: Warning: using inofficial libscg transport code version
(frueauf-scsi-bsd.c-1.40nb1 '@(#)scsi-bsd.c   1.40 01/03/18 Copyright 1997
J. Schilling').
scsibus15:
cdrecord: Warning: controller returns wrong size for CD capabilities page.
        15,0,0  1500) 'ASUS    ' 'CD-S500/A       ' '3.4H' Removable CD-ROM
        15,1,0  1501) 'PIONEER ' 'DVD-ROM DVD-104 ' '1.25' Removable CD-ROM
        15,2,0  1502) 'MATSHITA' 'CD-RW  CW-7585  ' '1.04' Removable CD-ROM

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