On Thu, 31 May 2001, Gunther Schadow wrote:

> > > > out the '92 (I think), but this's got me stumped.  Can the two ports
> > > be
> > > > bonded together, for twice the thruput?
> > >
> > > No.  Is there a sequencing cable/plug on the back?  Won't go without it.
> > 
> > Got one on the RA82.  Didn't see anything similar on the '92, tho.  But
> > the '92 boots.
> 
> Woops??? What's that? You can only hook a single SDI drive to a two
> board KDB50 controller gear? This sound's a bit of a waste! Did I 
> misunderstand something?

Think you did. The power sequencing cable is to prevent several RA8x
drives from spinning up at the same time on power on, since the power
consumption will blow the fuses. The RA9x drives are much nicer to your
power bills, so they don't have any power sequencing cables.

In short, the sequencing sable is only used for spin-up
sequencing. Without it, a RA8x drive will not spin up, but it has no other
function.

You can have up to four drives on a KDB-50 I'd guess, but to answer the
other posters question, no, you cannot hook both ports to different
controllers and double the data rate. The drive will only talk to one port
at a time, and the other will be on hold. You also need software that is
aware of the feature and will release the port when not talking to the
drive, so that the other port can have a go. Most systems *don't* do
this. Finally, if you did have a system that did this, you'd also have to
disable all disk caching if two different systems accessed the disk and
one of them have write access.

	Johnny

Johnny Billquist                  || "I'm on a bus
                                  ||  on a psychedelic trip
email: bqt@update.uu.se           ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol