Path: utzoo!attcan!uunet!timbuk!cs.umn.edu!kksys!com50!chris
From: chris@com50.c2s.mn.org (Chris Johnson)
Newsgroups: comp.periphs.scsi
Subject: Re: SCSI cable
Message-ID: <1990Oct19.164911.24264@com50.c2s.mn.org>
Date: 19 Oct 90 16:49:11 GMT
References: <1990Oct17.022235.22598@tkou02.enet.dec.com>
Organization: Com Squared Systems, Inc.
Lines: 46

In article <1990Oct17.022235.22598@tkou02.enet.dec.com> furuta@tkov51.enet.dec.com (My name is Akihiro Furuta) writes:
>I want to hook up hard disks to Sparc Station. Sparc has SCSI II type 
>connector and hard disks on market usually have SCSI I type 50-pin Anphenor
>connector. Where can I buy such cables in US?
>
>Akihiro Furuta
>Digital Equipment Corp Japan

Sun calls the SCSI connectors on the rear of the SPARCstations a
micro-miniature SCSI connector.  These connectors have 50 pins.

I don't believe that the SCSI 2 specifications include that connector
as one of the standard connectors, but I could be wrong.  Does someone
have a copy of the spec. and would be willing to check?

I think it's probably a misnomer to call that connector a SCSI 2
connector.  Sun implements a few of the SCSI 2 command features in its
latest machines, but does not, for example, support fast or wide SCSI 2.

The connector on most SCSI hard disks is a dual-row 50 pin flat cable
connector, and it is indeed one of several connectors specified in the
SCSI 1 specification as being a standard connector.  A 50 pin
Centronics-style connector is another of the standard connectors.

I've heard that the Sun "micro-miniature SCSI" connectors are made by
Honda.  I've also been told that 3M now makes an equivalent connector.
AMP (Amphenol) also makes them, since they are on the cables I have
laying here.  I believe we bought the cables we have here from a
distributor called DataLink.  I would image many of the larger cable and
electronics parts distributors like Anthem, Americable, and Pioneer
would carry the connectors, but I don't know about any specific company.
And of course, Sun sells a micro-miniature to 50 pin D (conveniently
non-standard for SCSI) cable, and it's easy to get 50 pin D to 50 pin
dual row parts for conversion cables.

I can just imagine what all this connector conversion stuff does to
cable impedances being correct.

I'd certainly like to know if there is a company that sells a cable that
has the micro-miniature connector on one end and the dual row on the
other.


-- 
   ...Chris Johnson          chris@c2s.mn.org   ..uunet!bungia!com50!chris
 Com Squared Systems, Inc.   St. Paul, MN USA   +1 612 452 9522