On Fri, Feb 04, 2005 at 07:21:59PM -0500, Gene Heskett wrote:
> Aha, LVD!  LVD is not compatible with the rest of the system unless 
> the rest of the system is also LVD.  It is two, completely seperate 
> signalling methods that just happen to use the same cabling.

Yes and no.  From the SCSI FAQ: "[ANSI] specified that if an LVD
device is designed properly, it can switch to S.E. [single-ended,
i.e. "normal", SCSI] mode and operate with S.E. devices on the
same bus segment."
  - http://h000625f788f5.ne.client2.attbi.com/scsi_faq/scsifaq.html#Generic099

So if you mix it with S.E., you lose its LVDness, e.g. you have
to stick to a S.E. bus length; but you shouldn't fry any
hardware.

HVD (high-voltage differential, i.e. the original differential
variant of SCSI) is another story completely!  That is indeed
flat-out incompatible with S.E. (and presumably with LVD too...)

--

|  | /\
|-_|/  >   Eric Siegerman, Toronto, Ont.        erics AT telepres DOT com
|  |  /
The animal that coils in a circle is the serpent; that's why so
many cults and myths of the serpent exist, because it's hard to
represent the return of the sun by the coiling of a hippopotamus.
	- Umberto Eco, "Foucault's Pendulum"