11 Apr
2001
11 Apr
'01
4:16 p.m.
The 50 pin with the hooks on the side is actually referred to as a
Centronics 50 pin, or SCSI-I (external SCSI as well on older machines before
SCSI-2 came along)
Most companies in the way back used either what was cheap or had specials
made up just to keep you coming to them for cables, connectors, etc. Why
does Apple had a different AUI port than anyone else? Why are there 9 pin
and 25 pin RS-232's.....Why is Apple's on an 8pin mini-din?
-----Original Message-----
From: owner-classiccmp(a)classiccmp.org
[mailto:owner-classiccmp@classiccmp.org]On Behalf Of Tony Duell
Sent: Wednesday, April 11, 2001 1:53 PM
To: classiccmp(a)classiccmp.org
Subject: Re: 50 pin SCSI to 50 pin centronics
What's causing all the confusion here is the nomenclature.
First of all,
there's only one Centronics connector
I've ever seen and that's
a 36-conductor
type. It was made for Centronics, which was at
one time, a
pretty good printer
Are you sure the 36 pin one was _made_ for Centronics? I've seen the 14,
24 and 50 pin ones on equipment a lot older than Centronics printers, and
I wouldn't be suprised if the 36 pin one wasn't used somewhere else as
well. Back then, it wasn't that common to have a custom connector made up
if there was a standard part that would do the job.
After all, 36 pins is not an ideal fit for the Centronics interface.
IIRC, there are some unassigned pins. If they were going to have it
custom-made, they could have had a 30 or 32 pin one made instead.
maker, though the Centronics line was pretty much
killed off by
the much better
and less costly substitutes imported for the PC
market some
years before there
even existed any notion of a standard for SCSI.
The old SCSI-1 uses a
50-position connector that looks like the Centronics type.
Prior to SCSI fame,
Sometimes. Sometimes (and this is in the standard IIRC), SCSI-1 used a
DD50 connector.
it was, and still is, widely used in the telecom
business. Not
being a telecom
type, I'm not aware of a generic name for
that type of connector.
Nor am I. HP called the 50 pin one a '50 pin Telco connector' at one
point. But I've never heard that name used for any of the smaller ones.
Over here the catalogues are split between 3 'generic' names for this
series of connectors :
'Centronics' (after the most popular use for the 36 pin one)
'IEEE-488' (after the most popular use for the 24 pin one)
'Amphenol' (after the company that IIRC first made them, even though they
make many other types of connector).
I tend to buy them by stock number :-)
SCSI, however, in its various versions, uses
connectors ranging from the
well-known and popular DB25 ( and a special smaller variant for
APPLEs ) to the
Well, the Mac+ used a normal DB25 for the SCSI port, just with a
different pinout to that which some other companies used at about the
same time...
-tony