[geeks] SCA question

[Kurt Mosiejczuk]

On Wed, 17 Apr 2002, Greg A. Woods wrote:

> I don't think that's a requirement, but it's certainly an allowed
> possibility.  Most such drives are identified as "LVD/SE".   I've heard
> tell of LVD drives that don't do SE, at least not correctly enough to
> live on a bus with other SE drives.

Hmmm... I thought it was a requirement and just assumed some drive makers
skimped on it (not that drive manufacturers would EVER play fast and loose
with newer specifications).  And short of me digging through the SCSI
spec (which I really don't feel like), I don't think I'll have a
definitive answer.

> > The low-voltage part means that while they are busy realizing what's
> > going on, the magic smoke doesn't get let out of the other drives and/or
> > host adapter, as can happen with HVD =)

> No, that's just due to the fact the 'L' stands for "low" and means about
> 1vdc, which isn't enough to smoke something normally expecting 5vdc.  :-)

> (as opposed the the 'H' standing for "high" and meaning +/- 12vdc, which
> in one signal state means quite an unexpected voltage differential!)

Well, I guess by "means" I was explaining a nice feature of it, not really
the exact electrical signaling =p (hah, does iso-8859-1 have that?) =)


--Kurt