50 pin SCSI to 50 pin centronics

From: Richard Erlacher <edick_at_idcomm.com>
Date: Thu Apr 12 01:04:17 2001

Yes, but the Centronics ones didn't. I once owned a QUME or DIABLO daisywheel
printer that used a card-edge connector as one of its options. I also owned a
DIABLO that used the 50-pin Blue-Ribbon style connector as appears on most
5-button telephone cables. That one had both the serial and the parallel
interface on the one connector. None of these were labelled CENTRONICS,
however.

I'm not blaming anyone for being as confused about what the right nomenclature
for that 50-pin connector type is as I am, but I am still convinced it's NOT
Centronics.

Dick
----- Original Message -----
From: "Russ Blakeman" <rhblake_at_bigfoot.com>
To: <classiccmp_at_classiccmp.org>
Sent: Wednesday, April 11, 2001 8:00 PM
Subject: RE: 50 pin SCSI to 50 pin centronics


> Many of the older Tandy/Radio Shack printers used the header and card edge
> connectors, or serial, as well.
>
> > -----Original Message-----
> > From: owner-classiccmp_at_classiccmp.org
> > [mailto:owner-classiccmp_at_classiccmp.org]On Behalf Of Richard Erlacher
> > Sent: Wednesday, April 11, 2001 7:17 PM
> > To: classiccmp_at_classiccmp.org
> > Subject: Re: 50 pin SCSI to 50 pin centronics
> >
> >
> > I had a Radio Shack Quick Printer II, which, IIRC, was a narrow, roll-fed
> > electrostatic erosion printer that used aluminum-foil coated roll
> > paper about 5"
> > wide. I used it to label my parts cabinets. Being a repackaged
> > Centronics
> > printer, it had the usual 36-pin Centronics connector.
> >
> > Centronics was using that 36-pin connector before Radio Shack
> > ever contemplated
> > getting into the compuer business. It was on the Printronix P100
> > we had on our
> > Wang 2200 MVP back in '75. The very first time I ever saw a real parallel
> > printer cable that didn't use the Centronics standard 36-position
> > connector at
> > both ends was on a PC, in 1981. Prior to that, the "toy"
> > interface used by the
> > Apple II was the only non-homemade one I saw in use on a
> > commercial system.
> > That was understandable in view of the package size constraints, however.
> >
> > Dick
> > ----- Original Message -----
> > From: "Tony Duell" <ard_at_p850ug1.demon.co.uk>
> > To: <classiccmp_at_classiccmp.org>
> > Sent: Wednesday, April 11, 2001 5:51 PM
> > Subject: Re: 50 pin SCSI to 50 pin centronics
> >
> >
> > > >
> > > > The 50-position type was around for a long time, i.e. I
> > remember them back
> > in
> > > > the early '70's and they weren't new then, in use with
> > telecom gear. I've
> > no
> > > > idea whether the 36-position variety was made_for_Centronics,
> > but it's the
> > only
> > > > connector that I've ever seen used on a genuine Centronics parallel
> > interface,
> > >
> > > At the printer end, probably (although there were a _few_
> > pre-PC printers
> > > that used a card edge or a header plug for a Centronics-like
> > interface --
> > > the Radio Shack Quick Printer 2 was one such IIRC).
> > >
> > > At the computer end, there were many connectors used. Some
> > companies used
> > > the 36 pin Blue Ribbon (I believe that _is_ the correct name). Others
> > > used a header plug or a card edge, normally pinned out so that an IDC
> > > ribbon cable with no twists could be used to link it to the 36 pin
> > > connector at the printer end. Things like the 34 pin card edge
> > on the old
> > > TRS-80s, for example.
> > >
> > > > be it on a Centronics, Printronix, Okidata, (not the toys
> > found attached to
> > a
> > > > PC, but the real "line-printers" ) or whatever sort of printer. The
> > interface
> > > > used on the PC parallel port does not precisely conform to
> > the Centronics
> > >
> > > The PC printer port was designed to link to the 5152 printer which was a
> > > badge Epson IIRC. That's why the interface is not _exactly_ Centronics.
> > >
> > > > standard, and was the first one I saw using a different
> > connector. The
> > point is
> > > > that while the connector isn't exclusive to that interface,
> > the interface is
> > > > exclusively dedicated to that connector, to wit, it's still
> > what's used on
> > > > printers, even though everybody knows it's only going to be
> > attached via a
> > DB25
> > > > at the computer end.
> > >
> > > Round here it might be _anything_ at the computer end :-)
> > >
> > > > 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.
> > > > >
> > > > That's the one widely used by SUN. It's a better connector,
> > but since they
> > >
> > > And others. The Ill-fated PERQ AGW3300 (aka PERQ3a) has a DD50 SCSI
> > > connector on it.
> > >
> > > > didn't make a crimp-onto-ribbon-cable version until very late
> > in the game,
> > it
> > >
> > > For SCSI, I've neve seen anything bu the crimp-on IDC type. The
> > pinout of
> > > SCSI-1 using that connector was chosen so you could crimp a DD50 onto a
> > > normal SCSI ribbon cable and get the right connections.
> > >
> > > Of course this doens't mean the connector didn't come out
> > relatively late
> > > -- I have no idea when the IDC version of the DD50 was first produced.
> > >
> > > -tony
> > >
> > >
> >
>
>
Received on Thu Apr 12 2001 - 01:04:17 BST