CD-ROM offer [ details on implementation ]

[Tom Glinos]

In article <1991Feb14.021900.8427 at odin.corp.sgi.com> olson at anchor.esd.sgi.com (Dave Olson) writes:
>In <9102131750.AA08632 at scripps.edu> jwk at SCRIPPS.EDU (John Kupec) writes:
>
>
>By the way, the CDROM drive(s) we end up supporting will have custom
>proms in the drive, in order to support booting from existing CPU
>proms.  The main change is to default to 512 byte blocks instead of
>2048, and secondarily to claim in the inquiry command that they are
>device type 0 (hard disk).  Re-powering the drive, or a SCSI bus reset
>will cause it to revert to the hard-disk mode (it has to do it on a bus
>reset for installs to work correctly after an init 0 without
>re-powering the CPU).
>

Why not change the boot proms on the CPU side instead?

Convince me that this would be more expensive than the charging scheme
that I see on the back of the CD-ROM jewel case.