20 Nov
2010
20 Nov
'10
7:41 p.m.
> > > On Wed, Nov 17, 2010 at 2:51 PM, Rob
Jarratt
> > > <robert.jarratt at ntlworld.com>
> > > wrote:
> > > > It is failing at the stage of detecting the disks with an
> > > > "invalid block size" error.
> > > >
> > > > I am using a CR-506 CD-ROM drive and the disks I have are RZ56
> > > > and
> RZ57.
> > >
> > > Could this be an issue with the CD-ROM not supporting 512byte
blocks?
> > I
know that microVAXen need this to install VMS, perhaps this is
> > true with Ultrix also.
> >
> > With some drives you have to set a jumper to force it to 512byte
blocks.
>
> -chuck
I found the sector size jumper on the CD-ROM and took it off, that was would not boot off the CD at all. So I can only
conclude that the
jumper
was
right before and was already set to a 512-byte
sector size. So I think
the conclusion is that the CD-ROM drive should be OK.
Regards
Rob
This got me wondering: is the sector size purely determined by the CD-ROM
drive reading the CD? Looking at Wikipedia would suggest that on the disk the sectors are always 2048 bytes, which implies
that the 512 sector
size is
something done by the reading device.
Regards
Rob
I have discovered that I can install Ultrix on the DECstation 5000 Model 240
if I use an RRD43 drive. It failed to work with a Matsushita CR-506-B, a
Matsushita CR-508-B and a Sony CDU55S.
Regards
Rob