Subject: Re: DUA7 on KDA50
To: Boris Gjenero <bgjenero@undergrad.math.uwaterloo.ca>
From: Arno Griffioen <arno@usn.nl>
List: port-vax
Date: 01/29/1998 08:33:03
> > SDI is a funky balanced-serial, phase-encoded horror. It was designed
> > that way so that there would be no charge buildup at either end. I
> 
> Why would anybody do such a thing?   Was this just an experiment in
> twisted design or was there a good reason?

Distance is what I would guess at. 

>From the rolled-up loop of SDI cable in the cabinet of my 3600 I guess
I could put a disk-cabinet a few meters away and still have some cable left..
Good for grouping disk-cabinets and CPU cabinets together.

Remember, those RA8x (and older) drives are 'rather large' in physical 
dimensions, so you need an interface that doesn't freak out at 2 meters 
cable length or so... (or much, much less in the case of a certain 
brain-dead PC drive interface type.. Hint: start's with an 'I' and
ends with 'DE' ;-)


								Bye Arno.

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