50 pin SCSI to 50 pin centronics

From: Russ Blakeman <rhblake_at_bigfoot.com>
Date: Wed Apr 11 17:17:22 2001

I'll have to dig but it was always referenced as a CENTRONICS-36 or
CENTRONICS-50 in our MIL-STD books and HP manuals when I was a
missile/eleectronics tech in the AF, until 95 when I retired. I keep contact
with a former coworker in OK that works for a contractor for the ACM/ALCM
project office and he has tons of references in his office and might be able
to locate it and fax or attach a copy to me.

> -----Original Message-----
> From: owner-classiccmp_at_classiccmp.org
> [mailto:owner-classiccmp_at_classiccmp.org]On Behalf Of Tony Duell
> Sent: Wednesday, April 11, 2001 4:07 PM
> To: classiccmp_at_classiccmp.org
> Subject: Re: 50 pin SCSI to 50 pin centronics
>
>
> >
> > 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)
>
> Do you have a reference for that (note : after the long discussion we had
> a couple of weeks back on the D-connector names, I am not going to take
> 'Well %company call them that in the catalogues' as a reference)?
>
> > 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?
>
> We went through this a few weeks back, didn't we? As I understand it :
>
> The Apple AUI port is different partly because it uses a 5V supply rather
> than the 12V one on a standard AUI port. So I guess it makes sense to
> have a different connector. We can argue for months whether Apple should
> have stuck to the standards, though.
>
> IIRC, the RS232 standard specifies a 25 pin connector. So strictly there
> are no 9 pin RS232 ports. If you mean why do PC/AT machines have a DE9P
> for the serial port, it was because (a) 9 pins is enough for the active
> signals on said port and (b) you can fit a DE and a DB on a single PC
> bracket, so you could have a combined parallel/serial adapter card. Which
> IBM introduced with the PC/AT IIRC.
>
> And Apple used the 8 pin mini-DIN on the Mac+ and later because there
> wasn't room for the DE9 connector used on the earler Macs. Hardware
> hackers have been complaining ever since -- those mini-DINs are about the
> worst connectors in the world to wire!
>
> -tony
>
Received on Wed Apr 11 2001 - 17:17:22 BST