Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cs.utexas.edu!uunet!ncrlnk!ncrcae!hubcap!dawill
From: dawill@hubcap.clemson.edu (david williams)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Apple SCSI not compatible with standard SCSI?
Summary: Miniscribe drives double-ended?
Message-ID: <7215@hubcap.clemson.edu>
Date: 28 Nov 89 03:08:17 GMT
References: <24105@cup.portal.com> <15450001@hpdml93.HP.COM>
Organization: Clemson University, Clemson, SC
Lines: 22

In article <15450001@hpdml93.HP.COM>, stephen@hpdml93.HP.COM (Stephen Holmstead) writes:
> Just a warning to people who want to get rid of 50 pin SCSI connectors
> (eg. Apple Computer):  Half of the pins on a 50 pin connector are
> grounds ONLY on a single-ended SCSI device.  On differential SCSI
> devices, all 50 pins are used.  When Apple went to a 25 pin SCSI port,
> they made a statement that do not want to consider anything but a
> single-ended SCSI device.  In the *REAL* world, people use 50 pins for
> both single-ended and differential drives, thus creating a 'standard'
> (heaven forbit if Apple ever used a 'standard' cable!). :-)
> 

     Hummm.  I am in the process of hacking together a 50pin-to-25pin connector
for a StarDrive I recently got.  The target drive (my roomate's) is a miniscribe
8425S.  Is this drive differential?  If not, how often is differential drive
used in the REAL world?  I have a feeling that this would only be used on 
really high-end drives, much as professional audio uses balanced connectors, and
consumer stuff only uses single-ended.

               Dave Williams
                 dawill@hubcap.clemson.edu
                     DAVE...DAVe...DAve...Dave...dave
                        "You think I'd really tell you what I'm up to?"