10 Apr
2001
10 Apr
'01
1:11 p.m.
does anyone have a cable that has 50 pin SCSI on one side and a 50 pin male
centronics on the other side? I need to connect an alternate boot disk to my
VS 4000/60, and I don't want to mess with the existing drives, and it'll
only be temporary while I try to fix my mistake in VMS, so it won't be in a
box or anything...
10 Apr
10 Apr
2:17 p.m.
By 50 pin SCSI do you mean the 50 pin header on the drive? The 50 pin
Centronics IS SCSI-1 as far as I know. If you wish to go from a 50 pin
SCSI-1 (centronics) to a 50 pin female header (as what goes to the drive)
then just get a 50 conductor ribbon, then a female IDC/IDS header and an
IDC/IDS centronics connector. Use a workbench vise carefully to crimp them
down and make sure pin 1 of the header is connected to pin 1 of the
Centronics.
-----Original Message-----
From: owner-classiccmp(a)classiccmp.org
[mailto:owner-classiccmp@classiccmp.org]On Behalf Of Billy D'Augustine
Sent: Tuesday, April 10, 2001 5:12 PM
To: classiccmp(a)classiccmp.org
Subject: 50 pin SCSI to 50 pin centronics
does anyone have a cable that has 50 pin SCSI on one side and a
50 pin male
centronics on the other side? I need to connect an alternate boot
disk to my
VS 4000/60, and I don't want to mess with the existing drives, and it'll
only be temporary while I try to fix my mistake in VMS, so it
won't be in a
box or anything...
3:07 p.m.
I have an external SCSI drive, which I want to connect to the external SCSI
port of my VAX 4000/60. The SCSI drive has a 50 pin connector. The VAX has a
50 pin centronics female. I'd like a cable to go between the two.
My point in posting was to avoid having to construct a cable (which I've
done previously, and no longer have the cable), or purchase one at inflated
prices.
By 50 pin SCSI do you mean the 50 pin header on the
drive? The 50 pin
Centronics IS SCSI-1 as far as I know. If you wish to go from a 50 pin
SCSI-1 (centronics) to a 50 pin female header (as what goes to the drive)
then just get a 50 conductor ribbon, then a female IDC/IDS header and an
IDC/IDS centronics connector. Use a workbench vise carefully to crimp them
down and make sure pin 1 of the header is connected to pin 1 of the
Centronics.
4 p.m.
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
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,
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.
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
now-popular 80-position SCA. The popular name of "SCSI-II" connector has
become
associated with the really small, fragile, and highly impractical 50-position
type common on CDR's etc, though I've seen it applied to the 68-pin WIDE SCSI
connector also commonly called a SCSI-III connector (don't ask me why).
Does anybody really know what's what in this context. It would really be nice
if the standard would name these connectors, but, last time I looked, it hand't
yet.
Dick
----- Original Message -----
From: "Billy D'Augustine" <azog(a)azog.org>
To: <classiccmp(a)classiccmp.org>
Sent: Tuesday, April 10, 2001 6:07 PM
Subject: Re: 50 pin SCSI to 50 pin centronics
I have an external SCSI drive, which I want to connect
to the external SCSI
port of my VAX 4000/60. The SCSI drive has a 50 pin connector. The VAX has a
50 pin centronics female. I'd like a cable to go between the two.
My point in posting was to avoid having to construct a cable (which I've
done previously, and no longer have the cable), or purchase one at inflated
prices.
By 50 pin SCSI do you mean the 50 pin header on
the drive? The 50 pin
Centronics IS SCSI-1 as far as I know. If you wish to go from a 50 pin
SCSI-1 (centronics) to a 50 pin female header (as what goes to the drive)
then just get a 50 conductor ribbon, then a female IDC/IDS header and an
IDC/IDS centronics connector. Use a workbench vise carefully to crimp them
down and make sure pin 1 of the header is connected to pin 1 of the
Centronics.
11 Apr
11 Apr
9:52 a.m.
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11:16 a.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
12:06 p.m.
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1:17 p.m.
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(a)classiccmp.org
[mailto:owner-classiccmp@classiccmp.org]On Behalf Of Tony Duell
Sent: Wednesday, April 11, 2001 4:07 PM
To: classiccmp(a)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
2:53 p.m.
Anything's possible for the military establishment, but I'd not bet on it being
right more than 1 ppm. This connector family is not old enough, methinks, to be
in any military standards. After all, they still love those nearly $1k/each in
100k quanatity 38999-series connectors and they still require that the wire be
#16 and soldered. A reference in a military document doesn't make it right.
You need a Centronics document.
Dick
----- Original Message -----
From: "Russ Blakeman" <rhblake(a)bigfoot.com>
To: <classiccmp(a)classiccmp.org>
Sent: Wednesday, April 11, 2001 4:17 PM
Subject: RE: 50 pin SCSI to 50 pin centronics
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(a)classiccmp.org
[mailto:owner-classiccmp@classiccmp.org]On Behalf Of Tony Duell
Sent: Wednesday, April 11, 2001 4:07 PM
To: classiccmp(a)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
12 Apr
12 Apr
3:15 a.m.
On Wed, 11 Apr 2001, Tony Duell wrote:
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.
Oh, but then you lose a lot of fun. The Amiga DB25 serial port features
among others audio output on some pins. =)
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!
Try a DIN-13 for size.
5:39 a.m.
In an earlier discussion of the RS232 connectors used in various systems it was
pointed out that DEC used the DE9 before anybody thought of the PC/AT.
Considering the common usage of so few of the defined signals on the DB25 and
the rarity of the cases wherein more than half-a dozen of the signals are
needed, I think it's reasonable for a system that uses lots of serial ports to
use a small connector.
However, as scantily documented as the signal set in the 9-pin connector has
been, I think it was a poor choice for the PC/AT. You can bet, however, that
someone got a big raise for thinking up a way to get two ports out through a
backpanel where only one might otherwise have fit, just as someone probably did
for thinking up that "twisted cable" scheme for PC floppy and hard disks.
Dick
----- Original Message -----
From: "Iggy Drougge" <optimus(a)canit.se>
To: <classiccmp(a)classiccmp.org>
Sent: Thursday, April 12, 2001 6:15 AM
Subject: Re: 50 pin SCSI to 50 pin centronics
On Wed, 11 Apr 2001, Tony Duell wrote:
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.
Oh, but then you lose a lot of fun. The Amiga DB25 serial port features
among others audio output on some pins. =)
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!
Try a DIN-13 for size.
9:50 a.m.
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12:09 p.m.
Tony Duell wrote:
So presumably using an all-pins-wired cable to link it to some true RS232
device that happens to implement all the pins is a good way to let magic
smoke out...
I've actually seen a device that has a single DB25 with the stnadard set
of RS232 signals on the stnadard pins (1-8 and 20 I think), and a
TTL-level Centronics-like parallel port on the other pins. Now that is a
device that you certainly don't connect to just any RS232 port.
Same goes with SCSI. I heard a story where a Mac was connected to a RS-232
terminal
via the Mac's SCSI connector. Ouch! The motherboard stopped functioning after
some of the terminal's +/- 12 volts started flowing thru it.
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.
Oh, but then you lose a lot of fun. The Amiga DB25 serial port features
among others audio output on some pins. =)
12:43 p.m.
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3:28 p.m.
What this really says is that in order to connect two devices, you have to know
precisely what you're doing. That's hard, nowadays, when the mfg's documents
are printed in large type on a business card. Things have gone downhill.
Manufacturers don't provide documentation because nobody reads it.
Dick
----- Original Message -----
From: "Tony Duell" <ard(a)p850ug1.demon.co.uk>
To: <classiccmp(a)classiccmp.org>
Sent: Thursday, April 12, 2001 12:50 PM
Subject: Re: 50 pin SCSI to 50 pin centronics
So presumably using an all-pins-wired cable to link it to some true RS232
device that happens to implement all the pins is a good way to let magic
smoke out...
I've actually seen a device that has a single DB25 with the stnadard set
of RS232 signals on the stnadard pins (1-8 and 20 I think), and a
TTL-level Centronics-like parallel port on the other pins. Now that is a
device that you certainly don't connect to just any RS232 port.
I have done (and a DIN14, which is actually easier to wire than the
DIN13). I still think the mini DIN 9 is the worst to do (it was used on the
mouse port of the Archimedes, for instance), and the mini DIN 8 is only
slightly better than the 9 (and a lot worse than the DIN 13 and DIN 14).
-tony
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.
Oh, but then you lose a lot of fun. The Amiga DB25 serial port features
among others audio output on some pins. =) 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!
Try a DIN-13 for size.
13 Apr
13 Apr
9 a.m.
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1:57 p.m.
> What this really says is that in order to connect
two devices, you have
>to know
> precisely what you're doing. That's hard, nowadays, when the mfg's
>documents
> are printed in large type on a business card. Things have gone downhill.
Someplace in my "collection" I have a "smart" cable, just plug it in
and it
configures itself for just about anything DB25.
3:43 p.m.
New subject: Serial Interfacing (was: 50 pin SCSI to 50 pin centronics
On Fri, 13 Apr 2001, Mike Ford wrote:
Someplace in my "collection" I have a
"smart" cable, just plug it in and it
configures itself for just about anything DB25.
I'm sure that there exist many things for which those work. But nothing
that I've ever tried to use them for. I have ALWAYS had to make a cable,
except one time connecting a votrax to a TRS-80 model 2 using a mountain
hardware matrix switch.
--
Grumpy Ol' Fred cisin(a)xenosoft.com
7:19 p.m.
New subject: Serial Interfacing (was: 50 pin SCSI to 50 pin centronics
On Fri, 13 Apr 2001, Fred Cisin (XenoSoft) wrote:
On Fri, 13 Apr 2001, Mike Ford wrote:
I got my first one in the early '80s when the installation tech(?) was
unable to determine the appropriate jumpers to solder into the
programmable shunt to make the new DEST 'Workless Station' OCR reader
communicate with the S-100 system that it was connected to. Since he
had it working with the SmartCable (the original one with only one
switch) but not with the shunt, I told the sales type that I would keep
the '...Cable'. He agreed. Not long after, I replaced it after solving
the shunt problem.
Subsequently, I found another one (the two switch version) and now have
both. Handy gadgets for 'quick and dirty' one time connections!
- don
Someplace in my "collection" I have a
"smart" cable, just plug it in and it
configures itself for just about anything DB25.
I'm sure that there exist many things for which those work. But nothing
that I've ever tried to use them for. I have ALWAYS had to make a cable,
except one time connecting a votrax to a TRS-80 model 2 using a mountain
hardware matrix switch.
--
Grumpy Ol' Fred cisin(a)xenosoft.com
4:29 p.m.
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6:58 p.m.
On Fri, 13 Apr 2001, Mike Ford wrote:
RS-232 only.
- don
> What this
really says is that in order to connect two devices, you have
>to know
> precisely what you're doing. That's hard, nowadays, when the mfg's
>documents
> are printed in large type on a business card. Things have gone downhill.
Someplace in my "collection" I have a "smart" cable, just plug it in
and it
configures itself for just about anything DB25.
10:31 p.m.
On Fri, 13 Apr 2001, Mike Ford wrote:
RS-232 only.
Actually I think it is supposed to be smart enough to handle serial/modem,
and I don't know about current loop. I haven't tried it with SCSI either,
but stranger things have happened. I think its called a smart comm so
likely SCSI is out.
BTW this cable has NO SWITCHES, its all automatic via some internal
circuit. I forget if it has anythng fancy like LEDs, but definately no
switches or jumpers.
> What
this really says is that in order to connect two devices, you have
>to know
> precisely what you're doing. That's hard, nowadays, when the mfg's
>documents
> are printed in large type on a business card. Things have gone downhill.
Someplace in my "collection" I have a "smart" cable, just plug it in
and it
configures itself for just about anything DB25.
14 Apr
14 Apr
9:32 a.m.
On Sat, 14 Apr 2001, Mike Ford wrote:
By IQ TECHNOLOGIES of Bellevue WA?
- don
On Fri, 13 Apr
2001, Mike Ford wrote:
RS-232 only.
Actually I think it is supposed to be smart enough to handle serial/modem,
and I don't know about current loop. I haven't tried it with SCSI either,
but stranger things have happened. I think its called a smart comm so
likely SCSI is out.
BTW this cable has NO SWITCHES, its all automatic via some internal
circuit. I forget if it has anythng fancy like LEDs, but definately no
switches or jumpers.
> What
this really says is that in order to connect two devices, you have
>to know
> precisely what you're doing. That's hard, nowadays, when the mfg's
>documents
> are printed in large type on a business card. Things have gone downhill.
Someplace in my "collection" I have a "smart" cable, just plug it in
and it
configures itself for just about anything DB25.
12:46 p.m.
On Sat, 14 Apr 2001, Mike Ford wrote:
["Smart Cable" for "ANY DB25"]
Actually I think it is supposed to be smart enough to
handle serial/modem,
and I don't know about current loop. I haven't tried it with SCSI either,
but stranger things have happened. I think its called a smart comm so
likely SCSI is out.
Not just "likely", ABSOLUTELY!
When you are ready to try it for non RS232 stuff, such as parallel, SCSI,
current loop, etc., please do the experiments on something disposable,
such as a current "state of the art" PC, or using disposable ISA cards and
printers, etc. Please don't toast any classics.
Let's look at HOW you would design something like that to work. It does
NOT connect all 25 wires, so it CANNOT possibly work for SCSI, parallel,
etc. It attempts to come up with the right combinations of pins
1,2,3,4,5,6,7,8, and 20. 1 and 7 are ground (chassis and signal). It
needs to take pins 2 and 3 ("Transmit" and "Receive") and decide
whether
to send them straight through or cross them over. Then it needs to
figure out which ones of 4,5,6,8, and 20 need to be passed through, which
need to be crossed over with others, and which need to be looped back to
others on the same side.
A well designed circuit can do some wondrous things, but will still have
major limitations. Many of the weird corruptions of the RS232 standard
will not be supported. Hence, they would NOT work on the things that I
was trying to do.
For programmers with soldering irons (such as myself), "The RS232
Solution" by Joe Campbell from Sybex provides a good help towards getting
RS232 cabling to work.
BTW, there IS a documented fatality from the frustrations of serial
interfacing.
--
Grumpy Ol' Fred cisin(a)xenosoft.com
1:37 p.m.
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4:53 p.m.
New subject: FSOT: "Smart Cable"s (was: 50 pin SCSI to 50 pin centronics
I don't know anything about the "NO switch" model.
I have two different ones (FSOT) BOTH are labeled as being model SC817.
They are from IQ Technologies, 11811 NE 1st St, Bellevue WA 98005. Each
has a male connector at one end ("Computer") and a header for connection
of a cable at the other end ("Peripheral"). The docs mention an
alternative model with a female connector at the computer end (for the
"new" IBM PC?)
One (earliest?) has a two position slide switch and three red LEDs,
labelled 'M', 'T', and 'D' You are supposed to try both positions
of the
switch to find the one where 'M' and 'T' light, and 'D' flickers.
The other has a two position slide switch, a three position slide switch,
two green LEDs, one red LED, and two yellow (tri-state?) LEDs. You are
supposed to set the three position switch in the middle, and set the two
position switch so that both yellow lights glow; then, if one of the green
LEDs glows, slide the three position switch towards it. The red LED is
supposed to flicker.
> 1,2,3,4,5,6,7,8, and 20. 1 and 7 are ground
(chassis and signal). It
On Sat, 14 Apr 2001, Tony Duell wrote:
Is it known that's all it connects? That's not
even going to work with
some printers (see mu earlier messages about printers that use pin 11 as
'busy').
I stand corrected; the docs obliquely mention "pin 11 or 19" (but only
mention them as being what the "print buffer full signal polarity switch
in the printer might be called" That reference to the switches in the
printer is the ONLY mention of individual RS232 signals.
ways (so that a cross between, say, 20 and 5 is
what's needed -- rememebr
that HP82164) then I can't see any easy way to automatically work out
what connections to make. I wish there was -- it would save me a few
hours with a breakout box sometimes.
Hmmm. that sounds like a task for a dedicated microcomputer, made from
say a Compaq luggable, with a program to try a lot of combinations and
sense which ones produce results. Then display/print a diagram of what
cable configuration worked in its simulation. It would be nice if the
"smart cable" were documented for "programmers with soldering irons"
as to
what cable to make to replace the device (they expect you to leave the
device in place).
Indeed. It sounds like another of those automatic
solutions that covers
the easy cases and makes a right mess of the complex ones. A lot of
modern products are like that....
In most cases, trying this device won't hurt anything. So using it to
solve the "easy cases" wouldn't be a problem.
My first experience with RS232 cabling (connecting a DTC300 daisy wheel
printer to a TRS-80 expansion interface) without any special tools took
weeks before I knew enough of what I was doing to get ink onto paper.
Thank you, Tony, for a reminder of how to proceed.
--
Grumpy Ol' Fred cisin(a)xenosoft.com
15 Apr
15 Apr
8:59 a.m.
New subject: FSOT: "Smart Cable"s (was: 50 pin SCSI to 50 pin centronics
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1:20 p.m.
New subject: FSOT: "Smart Cable"s (was: 50 pin SCSI to 50 pin centronics
On Sun, 15 Apr 2001, Tony Duell wrote:
But I can give you a dozen devices where that sort of
cable _won't_ work.
Thank you, but the "Smart Cables" haven't ever worked for any of the kinds
of things that I've needed, and another dozen devices added onto the stuff
that I already have wouldn't be much help - I need to get rid of a few
dozen cubic yards of stuff. I'm even having to [gasp!] get rid of
magazines and some books!
But I'm keeping almost all of my REAL breakout boxes. My favorite is a
lunch box sized one that has a row of dip switches for straight through
signals, jumper pads for crossing over, signal level meters, and a signal
generator that lets you set speed and number of bits and send a continuous
stream of four letter words!
--
Grumpy Ol' Fred cisin(a)xenosoft.com
1:33 p.m.
New subject: FSOT: "Smart Cable"s (was: 50 pin SCSI to 50 pin centronics
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8:51 p.m.
New subject: FSOT: "Smart Cable"s (was: 50 pin SCSI to 50 pin centronics
But I'm keeping almost all of my REAL breakout
boxes. My favorite is a
One of the swapmeets I go to had a guy last time with some of the nice
small units that have all 25 pins and a set of jumpers so that you can wire
the box any way you want to. Some how I forgot to buy a couple, and I have
been kicking myself ever since. I just hope they show up next time and I
won't hesitate.
14 Apr
14 Apr
1:44 p.m.
I hope you're joking, but if not, how did this occur? Electrocution? High
blood pressure due to frustration?
- Lanny
----- Original Message -----
From: Fred Cisin (XenoSoft) <cisin(a)xenosoft.com>
To: <classiccmp(a)classiccmp.org>
Sent: Saturday, April 14, 2001 7:16 PM
Subject: Re: 50 pin SCSI to 50 pin centronics
(snip)
BTW, there IS a documented fatality from the
frustrations of serial
interfacing.
--
Grumpy Ol' Fred cisin(a)xenosoft.com
7:50 p.m.
Probably bad advice, resulting in a shooting.
Dick
----- Original Message -----
From: "Lanny Cox" <chronic(a)nf.sympatico.ca>
To: <classiccmp(a)classiccmp.org>
Sent: Saturday, April 14, 2001 4:44 PM
Subject: Re: 50 pin SCSI to 50 pin centronics
I hope you're joking, but if not, how did this
occur? Electrocution? High
blood pressure due to frustration?
- Lanny
----- Original Message -----
From: Fred Cisin (XenoSoft) <cisin(a)xenosoft.com>
To: <classiccmp(a)classiccmp.org>
Sent: Saturday, April 14, 2001 7:16 PM
Subject: Re: 50 pin SCSI to 50 pin centronics
(snip)
BTW, there IS a documented fatality from the
frustrations of serial
interfacing.
--
Grumpy Ol' Fred cisin(a)xenosoft.com
6:39 p.m.
Lots of experience, yes, but expertise . . . well . . . not enough.
Dick
----- Original Message -----
From: "Fred Cisin (XenoSoft)" <cisin(a)xenosoft.com>
To: <classiccmp(a)classiccmp.org>
Sent: Monday, April 16, 2001 11:01 AM
Subject: Re: 50 pin SCSI to 50 pin centronics
On Sat, 14 Apr 2001, Richard Erlacher wrote:
Probably bad advice, resulting in a shooting.
VERY close guess!
Can we assume from that that you have lots of expertise with serial
interfacing?
--
Grumpy Ol' Fred cisin(a)xenosoft.com
14 Apr
14 Apr
2:44 p.m.
On Sat, 14 Apr 2001, Fred Cisin (XenoSoft) wrote:
BTW, there IS a documented fatality from the
frustrations of serial
interfacing.
And I hope you're going to follow up with the story :)
Sellam Ismail Vintage Computer Festival
------------------------------------------------------------------------------
International Man of Intrigue and Danger http://www.vintage.org
13 Apr
13 Apr
4:49 a.m.
On Thu, 12 Apr 2001, Tony Duell wrote:
So presumably using an all-pins-wired cable to link it to some true RS232
device that happens to implement all the pins is a good way to let magic
smoke out...
I suppose that might be the case, but I don't really think the
Commodore/Amiga engineers were stupid enough to place those outputs at
volatile positions.
According to HWB, they're at pins 11 and 18.
I have done (and a DIN14, which is actually easier to wire than the
DIN13). I still think the mini DIN 9 is the worst to do (it was used on the
mouse port of the Archimedes, for instance), and the mini DIN 8 is only
slightly better than the 9 (and a lot worse than the DIN 13 and DIN 14).
It's bad enough that there aren't any "shoes" for the cables, but the
density gives it a striking resemblance to a jungle.
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.
Oh, but then you lose a lot of fun. The Amiga DB25 serial port features
among others audio output on some pins. =) I've actually seen a device that has a single DB25
with the stnadard set
of RS232 signals on the stnadard pins (1-8 and 20 I think), and a
TTL-level Centronics-like parallel port on the other pins. Now that is a
device that you certainly don't connect to just any RS232 port.
What about those two-in-one DB 25 serial ports seen on SUNs and big-name
PCs?
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!
Try a DIN-13 for size.
9:17 a.m.
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10:07 a.m.
At 07:17 PM 4/13/01 +0100, Tony Duell wrote:
Oh, brilliant... Many serial printers (Epson, etc) have
the busy line on
pin 11. So plug that into an Amiga serial port with a straight-through
cable and you'll cook something in the sound circuitry.
Yes, and back in the day, I seem to remember that Amigans did.
The custom cable-making companies also did brisk business, due
to the odd serial port and video ports of the Amiga. I also
remember conflicts with scanners, where people would mistakenly
plug it into the parallel port when it belonged on a SCSI port
connector.
- John
4:13 p.m.
see below, plz.
----- Original Message -----
From: "John Foust" <jfoust(a)threedee.com>
To: <classiccmp(a)classiccmp.org>
Sent: Friday, April 13, 2001 1:07 PM
Subject: Re: 50 pin SCSI to 50 pin centronics
At 07:17 PM 4/13/01 +0100, Tony Duell wrote:
Since when do
serial printers have a BUSY line at all?
Dick
Oh, brilliant... Many serial printers (Epson, etc)
have the busy line on
pin 11. So plug that into an Amiga serial port with a straight-through
cable and you'll cook something in the sound circuitry.
Yes, and back in the day, I seem to remember that Amigans did.
The custom cable-making companies also did brisk business, due
to the odd serial port and video ports of the Amiga. I also
remember conflicts with scanners, where people would mistakenly
plug it into the parallel port when it belonged on a SCSI port
connector.
- John
4:26 p.m.
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4:51 p.m.
I've revisited the RS232 signal definitions and can't see one called
"busy". I
know about software handshaking, and even hardware handshaking, but I don't know
of a 'busy" signal. Which pin is that?
Dick
----- Original Message -----
From: "Tony Duell" <ard(a)p850ug1.demon.co.uk>
To: <classiccmp(a)classiccmp.org>
Sent: Friday, April 13, 2001 7:26 PM
Subject: Re: 50 pin SCSI to 50 pin centronics
Oh, most do. The really old ones (Teletypes, Decwriters, etc) don't --
they operate at a baud rate low enough that you can't send characters
too fast for them. But most more recent printers have some kind of
internal buffering and handshaking -- either software handshaking
(XON/XOFF, ETX/ACK) or hardware handshaking (Busy line, for example).
Epsons (and things emulating Epsons, and more recent DECwriters, like the
LA100) seem to put the busy signal on pin 11 (at RS232 levels, of
course). Some other makes (like my Apple LW2NT) use the normal lines
(RTS, DTR, etc) for this.
-tony
At 07:17 PM 4/13/01 +0100, Tony Duell wrote:
Since when do
serial printers have a BUSY line at all? Oh, brilliant... Many serial printers (Epson, etc)
have the busy line on
pin 11. So plug that into an Amiga serial port with a straight-through
cable and you'll cook something in the sound circuitry.
14 Apr
14 Apr
8:44 a.m.
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10:15 a.m.
Actually, I don't think the standard prohibits anything in terms of how the
lines are used. If you sneak power from one or another of them, that's fine. I
must have misunderstood what you wrote to say that there was a signal redefined
as BUSY, while there's no reason you can't use a signal on the DB25 for more or
less any purpose. There are some that are defined in a way that might
discourage you from using a signal as handshake or status signal, but there's
really no reason you have to use CTS or DTR in the usual way.
Dick
----- Original Message -----
From: "Tony Duell" <ard(a)p850ug1.demon.co.uk>
To: <classiccmp(a)classiccmp.org>
Sent: Saturday, April 14, 2001 11:44 AM
Subject: Re: 50 pin SCSI to 50 pin centronics
>
> I've revisited the RS232 signal definitions and can't see one called
"busy".
I
No, and you can't find one called 'mouse power' either, for all many
serial mice take their power from the RS232 port....
Seriously, I guess such printers probably shouldn't be called 'RS232'
because they most definitely use some of the hardware handshake lines in
ways that the standard forbids. On the other hand, just about all 'RS232'
devices do that now.
It has become a de-facto standard to use RTS/CTS and/or DSR/DTR as
hardware handshake lines. In the sense that if you are transmitting, you
look at the state of the CTS input, and only transmit when it's asserted.
This _is_ contrary to the official RS232 standard, agreed.
If you do use RTS/CTS like that, it would be reasonable to call CTS a
READY or BUSY input (the only difference between those 2 for a printer is
the polarity).
> know about software handshaking, and even hardware handshaking, but I don't
know
of a
'busy" signal. Which pin is that?
If you want a silly answer : Pin 11. After all, that's where most
printers seem to put it.
I have just picked up the user manual for the DEC Letterprinter 210
(basically an LA100 in a different box!). There is a table (page 25 in my
edition) that is headed :
'The printer supports the folloing RS232C interface signals
Pin Source Name Function
[...]
11 Printer BUSY Restraint
[...] '
Now, I happen to know that is not part of the official RS232 spec, but it
certainly seems to be a de-facto standard...
Although, interestingly, the next section in the manual (setting the DIP
switches) includes the line :
'Set switch A-1 down for transmission restraint using the EIA BUSY
control line.'
So maybe it did later become part of an EIA spec?
-tony
11 Apr
11 Apr
12:11 p.m.
On Wed, 11 Apr 2001, Russ Blakeman wrote:
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)
What are colloquially referred to as Centronics connectors are, I
believe, properly called Ribbon connectors, derived from the name "Blue
Ribbon" that Amphenol gave them originally.
- don
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
2:46 p.m.
see below, plz.
Dick
----- Original Message -----
From: "Russ Blakeman" <rhblake(a)bigfoot.com>
To: <classiccmp(a)classiccmp.org>
Sent: Wednesday, April 11, 2001 2:16 PM
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)
I've seen that too, but the folks making the reference don't know their
butt
from a hot rock. Centronics never (at least as far as
I have seen) used that
common 50-pin version that looks like the 36-pin version they
had named after
their popular application. 20 years ago things were much clearer in this regard
because you didn't have idiots selling and advertising things they didn't
understand at all. Sadly, that's no longer the case.
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?
In the "way back" an apple was something you had in your lunch sack, not
on
your desktop. The evolution of the "Apple computer" coincides more or less
with
the beginning of the end of intelligible conversation about such matters. The
justification for such things was probably cost and size, but "real" AUI still
lives on a DA-15 connector. Back in those days, RS232C spelled out the signal
levels and the signal names, and their functions, though quite inadequately, and
it wasn't the EIA that authorized the use of the DE9 for RS232-compatible
communcation, thoguh I don't know why, in view of the fact that only DB25-pins
2,3, and 7 were required to get the job done. Even today, lots of people talk
about RS232 when they're really talking about asynchronous serial communciation.
-----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
3:45 p.m.
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8:59 p.m.
Well, that's certainly true. The EIA standard wouldn't spell out all those
signal name assignments if it didn't need them in the most general case.
However, in most cases, notably the popular DEC interfaces, it became common to
see just the three-wire hookup, probably because the DEC systems were tied to so
many terminals, often being front-enders, etc. That made for skinny cables that
didn't weigh as much nor did they take up as much space.
The first time I used a serial printer of my own, I found that the only way to
get around the all-too-common incompatibilities between printer handshake and
system handshake was to ignore the handshakes (i.e. turn them off) and make no
connections other than TxD, RxD, and Common.
more below ...
Dick
----- Original Message -----
From: "Tony Duell" <ard(a)p850ug1.demon.co.uk>
To: <classiccmp(a)classiccmp.org>
Sent: Wednesday, April 11, 2001 6:45 PM
Subject: Re: 50 pin SCSI to 50 pin centronics
> lives on a DA-15 connector. Back in those days,
RS232C spelled out the
signal
> levels and the signal names, and their functions,
though quite inadequately,
and
> it wasn't the EIA that authorized the use of
the DE9 for RS232-compatible
> communcation, though I don't know why, in view of the fact that only
DB25-pins
> 2,3, and 7 were required to get the job done.
Even today, lots of people
talk
Well, firstly, 2,3,7 are not always all you need. Synchronous interfaces
almost certainly need the clock signals (on 15, 17 and maybe 24?). You
might also need the modem control [1] lines, etc. There are many more
than 9 signals, so you can't always use a 9 pin connector.
And one reason for having a standard in the first place is so that (at
least in principle) any 2 devices meeting the standard can work together.
If some devices have a 9 pin connector and others have a 25 pin
connector, then you can't plug them together.
Yes, I know 'RS232 compatible' normally means a morning with schematics
and an afternoon with the breakout box working out how to link the darn
thing up. But that's because we're _all_ misusing the interface. It was
designed to link a teletype to a modem, and for that use, it seems to
work first time.
Sad but true ... The standard links the pins to the signal names, and sketchy
definitions of the signal functions, but doesn't even go so far as to define the
active state of the handshakes, thereby leaving much room for confusion.
[1] I have deliberately avoided calling them hardware handshake lines.
IIRC the standard is pretty clear about what you can do with them, and
hardware handshaking is not included. This makes sense in the original
application -- the RS232 link was between a terminal and a modem -- a
dumb modem with no internal data buffering or anything like that. The
device you wanted to tell to stop sending characters was the computer
connected to the modem at the other end of the line. The only way you
could do that was by sending signals -- characters -- over the telephone
line. You couldn't simply send a signal to the local modem, which is
what, of course, the control lines did. No, those lines were for things
like ensuring the modem was working, doing a half duplex turnaround, etc.
That's probably wise, and, in fact, wiser than most authors about this
subject.
Now, of course, we have a pretty good idea of how we expect those lines
to hehave -- as hardware handshake lines -- even though that is against
the standard. In fact when you find a device that uses them 'properly',
you might have a long day ahead of you making it work with just about any
other device out there.
Whenever I need a taste of humility, I get out my manuals for the HP 7585
plotter's serial interface and try to figure out how it's really supposed to
work. Though I've gotten it to work, I've never understood why it works the way
it appears to while the doc's say what they say.
-tony
12 Apr
12 Apr
9:42 a.m.
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3:13 a.m.
On Wed, 11 Apr 2001, Russ Blakeman wrote:
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)
I've got a fast SCSI-2 card with a Centronics 50 "SCSI-1" connector. Feels
really sturdy and heavy-duty.
11 Apr
11 Apr
2:37 p.m.
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,
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
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.
The 24-position type is used on HPIB, though I doubt there aren't other
applications. I've seen others as well, but nobody who's been around refers to
the 50-pin, 24-pin, or anything else other than the 36-pin version of this
particular connector series as a Centronics connector without risk of ridicule.
I think one U.S. manufacturer (Amphenol ???) made these under the "Blue Ribbon"
moniker, though I can't find any old enough connector catalogs to prove it.
more below ...
Dick
----- Original Message -----
From: "Tony Duell" <ard(a)p850ug1.demon.co.uk
To: <classiccmp(a)classiccmp.org
Sent: Wednesday, April 11, 2001 12:52 PM
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
the
My mistake ... I was thinking about their FD
connector, (?) or whatever it was,
some sort of almost-B-shell with only room for 19 pins.
> 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
> 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.
That's the one widely used by SUN. It's a better connector, but since
they
didn't make a crimp-onto-ribbon-cable version until very late in the game, it
was not adopted as the standard. I do believe it's in the standard by now,
though, and that some firms other than SUN are using it.
> 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
2:51 p.m.
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3:16 p.m.
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(a)p850ug1.demon.co.uk>
To: <classiccmp(a)classiccmp.org>
Sent: Wednesday, April 11, 2001 5:51 PM
Subject: Re: 50 pin SCSI to 50 pin centronics
point
is
SCSI
it
>
> 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 > 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
fame,
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,
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
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
3:35 p.m.
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5 p.m.
Many of the older Tandy/Radio Shack printers used the header and card edge
connectors, or serial, as well.
-----Original Message-----
From: owner-classiccmp(a)classiccmp.org
[mailto:owner-classiccmp@classiccmp.org]On Behalf Of Richard Erlacher
Sent: Wednesday, April 11, 2001 7:17 PM
To: classiccmp(a)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(a)p850ug1.demon.co.uk>
To: <classiccmp(a)classiccmp.org>
Sent: Wednesday, April 11, 2001 5:51 PM
Subject: Re: 50 pin SCSI to 50 pin centronics
SCSI-1
uses a
>
> 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 > > > 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
9:04 p.m.
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(a)bigfoot.com>
To: <classiccmp(a)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(a)classiccmp.org
[mailto:owner-classiccmp@classiccmp.org]On Behalf Of Richard Erlacher
Sent: Wednesday, April 11, 2001 7:17 PM
To: classiccmp(a)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(a)p850ug1.demon.co.uk>
To: <classiccmp(a)classiccmp.org>
Sent: Wednesday, April 11, 2001 5:51 PM
Subject: Re: 50 pin SCSI to 50 pin centronics
SCSI-1
uses a
>
> 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 > > > 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
9:02 p.m.
On Wed, 11 Apr 2001, Richard Erlacher wrote:
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.
Just to muddy the waters a tad, do not forget that Xerox used a 50-pin
Ribbon connector on some version of the Diablo 630 (IIRC) in what they
called their (A)ll (P)urpose (I)nterface - API - which included
parallel, serial, and I forget what all else.
- don
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(a)p850ug1.demon.co.uk>
To: <classiccmp(a)classiccmp.org>
Sent: Wednesday, April 11, 2001 5:51 PM
Subject: Re: 50 pin SCSI to 50 pin centronics
point
is
SCSI
it
>
> 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 > 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
fame,
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,
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
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
9:23 p.m.
The API had RS-232, 20 ma current loop, and parallel, all on the one connector.
I actually had a couple of those. I'm ashamed to admit I once owned and used
eight daisywheel printers in order to generate letter-quality output. I was too
cheap to buy a laser printer, and the "lotsa printers" got the work out. They
made "lotsa noise" too. I wonder how long it will be before I stop finding
spare logic boards, ribbons, and printwheels.
Dick
----- Original Message -----
From: "Don Maslin" <donm(a)cts.com>
To: <classiccmp(a)classiccmp.org>
Sent: Thursday, April 12, 2001 12:02 AM
Subject: Re: 50 pin SCSI to 50 pin centronics
On Wed, 11 Apr 2001, Richard Erlacher wrote:
<snip>
Just to muddy the waters a tad, do not forget that Xerox used a 50-pin
Ribbon connector on some version of the Diablo 630 (IIRC) in what they
called their (A)ll (P)urpose (I)nterface - API - which included
parallel, serial, and I forget what all else.
- don
> 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(a)p850ug1.demon.co.uk>
> To: <classiccmp(a)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
12 Apr
12 Apr
3:28 a.m.
Here's an interesting page from an online 1997 hardware book that might help
or hinder this "centronics" discussion...
http://www.viking.delmar.edu/courses/CIS312J/EBOOK/wrh19.htm#E69E399
11 Apr
11 Apr
5:15 p.m.
Billy D'Augustine wrote:
I have an external SCSI drive, which I want to connect
to the external SCSI
port of my VAX 4000/60. The SCSI drive has a 50 pin connector. The VAX has a
50 pin centronics female. I'd like a cable to go between the two.
Jerome Fine replies:
With all the comments about the types of centronics cables, did you find the
cable you want?
If not, I might be able to help, but you still have not specified the computer
end of the cable carefully enough. I assume that if both ends of the cable
were the same (50 pin centronics male - i.e. the external drive has the normal
50 pin centronics female), you would have said so. This type of cable is
almost always used to connect two external drives to each other and extend
the SCSI daisy chain since most external SCSI drives have two 50 pin
centronics female connectors. If hope that what I have said is not confusing.
I have a number of external Sony SMO S501 magneto optical drives and
one one occasion I wanted to connect four drives to the host adapter in the
computer. The cable to the first drive has a 50 pin centronics male connector
at the external drive end. The extension cable has two 50 pin centronics
connectors - one at each end - and is used to connect the first external drive
to the second external drive. Two more of these double ended cables (50 pin
centronics male at both ends) are then used to connect the 3rd and 4th external
drives.
The only cable that is different is the cable with the end attached to the host adapter.
Since this is not a closed up system (the side panels are always off), I just used
a cable with a 50 pin female header on the end and attached it directly to the
SCSI host adapter in the computer what has a 50 pin male header connection.
What you have not specified thus far is what the VAX connection consists of!
I presume it is a 50 pin connection. Is it centronics? Male or female? Is it a
header? Male or female? Is it something else. On most systems where a direct
connection is made to the host adapter (which often has a 50 pin male header
connection on the host adapter), a flat cable is used. If you need a shielded
round cable, you also need to specify that aspect as well. I am not trying to
be picky, but I can think of about 12 different cables that have a 50 pin male
centronics at one end and something else at the other end. Do you think you
could let us know exactly what you are looking for?
Sincerely yours,
Jerome Fine
10 Apr
10 Apr
2:22 p.m.
does anyone have a cable that has 50 pin SCSI on one
side and a 50 pin male
centronics on the other side? I need to connect an alternate boot disk to my
VS 4000/60, and I don't want to mess with the existing drives, and it'll
only be temporary while I try to fix my mistake in VMS, so it won't be in a
box or anything...
Does the 4000 use 50 pin scsi... the VaxStation3100 here's got a wierd
68pin.
I do have a 50pin centronix to 50 pin SCSI II micro connector.
You do mean the stuff used on Sun Sparcstation I and higher workstations
to go to scsi.
Bill
--
bpechter(a)monmouth.com | FreeBSD since 1.0.2, Linux since 0.99.10
Brainbench MVP | Unix Sys Admin since Sys V/BSD 4.2
Unix Sys.Admin. | Windows System Administration: "Magical Misery Tour"
3:29 p.m.
68 pin should be SCSI-2 I think
-----Original Message-----
From: owner-classiccmp(a)classiccmp.org
[mailto:owner-classiccmp@classiccmp.org]On Behalf Of Bill Pechter
Sent: Tuesday, April 10, 2001 6:22 PM
To: classiccmp(a)classiccmp.org
Subject: Re: 50 pin SCSI to 50 pin centronics
does anyone have a cable that has 50 pin SCSI on
one side and a
50 pin male
centronics on the other side? I need to connect
an alternate
boot disk to my
VS 4000/60, and I don't want to mess with the
existing drives, and it'll
only be temporary while I try to fix my mistake in VMS, so it
won't be in a
box or anything...
Does the 4000 use 50 pin scsi... the VaxStation3100 here's got a wierd
68pin.
I do have a 50pin centronix to 50 pin SCSI II micro connector.
You do mean the stuff used on Sun Sparcstation I and higher workstations
to go to scsi.
Bill
--
bpechter(a)monmouth.com | FreeBSD since 1.0.2, Linux since 0.99.10
Brainbench MVP | Unix Sys Admin since Sys V/BSD 4.2
Unix Sys.Admin. | Windows System Administration:
"Magical Misery Tour"
8:05 p.m.
68 pin should be SCSI-2 I think
It's usually wide scsi... but DEC used it for some wierd purpose on
non-wide stuff with their own pinout.
Bill
--
bpechter(a)monmouth.com | FreeBSD since 1.0.2, Linux since 0.99.10
Brainbench MVP | Unix Sys Admin since Sys V/BSD 4.2
Unix Sys.Admin. | Windows System Administration: "Magical Misery Tour"
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