6 Sep
2007
6 Sep
'07
6:13 a.m.
On Wednesday 05 September 2007 11:47, der Mouse wrote:
I'm thinking 37...
[...] a 25-pin
D connector reminscent of the Mac "SCSI" connectors on
Mac Plus and other machines. [...]
Forgotten what the correct designation for those D-connectors is, and
wanted to get this out fast in case anyone wants it.
The 25-pin size - the one used for the MAC SCSI you refer to, the one
called for by the mechanical portion of the RS-232 spec, the one used
for peecee parallel ports - is DB.
Using pin count for that same pin spacing, the table is DA=15, DB=25,
DC=39 (I think), DD=50 (three rows), DE=9. The DE shell is also used
in a 15-pin variant ("VGA"), but the pins are spaced substantially
closer than in the DE-9. DA is probably best known for peecee joystick
connectors, but it also got used for AUI Ethernet back in the 10base5
days, before even 10base2, much less 10baseT. DC doesn't get used much
in my experience; I think I have a few SBus cards that use it for the
fat end of their octopus cables.
Didn't the original peecee's floppy adapter card have one of those on the
metal bracket to connect external floppy drives with? I had an external IBM
floppy drive a while back, pulled the drive out of the box to use for
something, and now I have this box with a little bitty switching power
supply in it and a short cable with one of those connectors on the end of
it...
DD was used by Sun for SCSI back in the Sun-2 and
Sun-3 era, and also got
used for IPI disks. DE is probably best known for peecee serial ports
and "VGA" video (a lot of people don't realize the shell size is the same
for those two), but I've seen it used for other things, such as Sun-3
monochrome video. I'm sure each size has plenty of other uses I know nothing
about, too.
Joystick ports on lots and lots of things, the c64, vic-20, Yamaha CX5,
Atari 2600 (?) game consoles, etc.
I don't know why they are out of order. I
speculate that someone
designed DA through DD, never expecting D-shell to get used for
anything under 15 pins, then had to tack on the 9-pin size later.
(Arguably they should have called it D@, but that would probably have
been too geeky. :)
:-)
There exist D-shell connectors of other sizes, like
the NeXT "black"
hardware video connector (which held something like 19 pins). I don't
know whether they have names in the DA..DE series; I suspect they have
no standard names because they're not standard sizes.
Didn't the Atari ST machines use something odd of the sort? I'm thinking it
had 23 pins but I've never actually seen one of those or worked with one.
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin