Half on, half off -- New CD-R drive and 512-byte blocks - test-drb@ccmp.vtda.org

9 Apr 2002

...
  From: Christopher Smith &lt;csmith(a)amdocs.com&gt;
 To: "Classiccmp (E-mail)" &lt;classiccmp(a)classiccmp.org&gt;
 Subject: Half on, half off -- New CD-R drive and 512-byte blocks
 Date: Tue, 9 Apr 2002 15:17:56 -0500 

 I just bought a new CD-RW drive -- a Sony CRX145s -- and am curious
 about whether it may read the 512-byte blocks necessary for using it
 as a backup boot device on my VAXen, Sparc, SGI, etc.

 Does anyone know whether this, or just for information, some other
 CD-RW unit, will do such a thing?

 Note that I do know that discs are written in 2048 byte blocks, and
 the answer won't affect its performance in writing disks on these
 systems.  I am also aware that doing this for the long term may 
 needlessly shorten the life of the drive.  As I said above, it is
 more for curiosity, and eventually I would like to know that in case 
 my RRD42 dies, I have a backup. :) 
A minute or two with Google led me to
<
http://sony.storagesupport.com/dlagreement.zulu?dlid=cdrw/downloads/Crx145s…
>
which is the manual for this drive.  Looking carefully I see that it has
5 pairs of configuration jumper pins.  Three for setting the SCSI ID,
one for termination, and one "test block do not jumper".  Your guess is
as good as anyone else's.

    carl
-- 
        carl lowenstein   marine physical lab   u.c. san diego
                                          clowenstein(a)ucsd.edu