On Jul 26, 19:31, Bill Pechter wrote:
> > Several transceivers connected to the same cable allow several machines
> > to communicate. In a sense, the transceivers together with the coax
cable
> > form the hub.
> >
> > The T-pieces are, indeed passive (all 3 connectors connected in
parallel
> > in the obvious way), but they're not really the hub.
> >
> > -tony
>
> It's really that the hub doesn't exist on a bus network like 10Base2
> or 10Base5... all the Tee connectors are doing is replacing
> the vampire tap on thicknet...
> The thinnet "Transceiver" is really built on to the card on
> most PC's and is the same (basically) as the old thicknet
> transceiver attached to my Sun my Unix boxes -- they can go from
> Thinnet to Thicknet by swapping the N-Connector top to the
> BNC connector top. And thinnet can go to thicknet with just an N to BNC
> adapter -- but the max length and specs drop to thinnet specs.
>
> Hubs really distort the logical ethernet bus topology.
Not really. Logically, the innards of the hub are the bus. The ports are
the taps. Then, since the stations connected are typically some distance
away, you use an appropriate technology to get the cable to them, and
that's why there are additional transceivers (one on the host card, one on
the hub port) to drive the signal over a resonable distance. It certainly
changes the physical layout of course (short bus long drops instead of a
long bus with short drops).
> Now 10/100 switches really screw with it.
Those switches are just bridges, which have been around for decades (albeit
with fewer ports).
--
Pete Peter Turnbull
Network Manager
University of York
Uhhhh, my 11/750 has a standard normal-looking 3 prong standard-outlet
fitting plug.. It never has had a 30A twist-n-lock connector in all the time
I've owned it... Is this a bad thing?
Will J
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On Jul 27, 23:15, Tony Duell wrote:
> > On Jul 26, 18:38, Tony Duell wrote:
> > > There seems to be a 6522 (on the BBC side) with the ports connected
to
> > > the ports of the 8255. That seems to be on the Z80 bus.
> >
> > I've not looked at one for a while, but that makes more sense.
Presumably
> > the 6522 is mapped into the Beeb's 1MHz bus space.
>
> Don't you mean _Tube_ address space ? :-)
Er, yes, that was a typo, induced by trying to type 15 minutes of email in
a 5-minute slot :-)
In fact, part of the reason the Torch board causes Beebs to misbehave if
Torch's own code doesn't grab it and hide it, is that the 6522 is seen by
Acorn's Tube code (in the DNFS ROM) and Acorn's code will try to initialise
it (and gets it wrong, of course).
--
Pete Peter Turnbull
Network Manager
University of York
> >You forgot A/UX.
>
> Funny you should mention A/UX, I have my notebook full of original floppies
> sitting here by my desk waiting to have them all imaged and put on a CDR.
> Assuming all the floppies can be read, I plan to make a few extra CDRs.
All my copies of A/UX came on CD. In fact, A/UX led me to buy my first
CDROM drive.
--
Eric Dittman
dittman(a)dittman.net
> >I used to run A/UX on a II (later IIfx) and I liked it. I
> >didn't find it all that much slower than running the MacOS
> >straight. I can even remember playing Hellcats (I think
> >that was the name; it was a WWII flight simulator) under
> >A/UX and it was pretty smooth.
>
> Was the version you were running a C2 version? I was running A/UX 2.0/C2,
> it was painful.
No, I ran the standard version. Also, things greatly improved
with 3.0.
--
Eric Dittman
dittman(a)dittman.net
> >You forgot A/UX.
>
> That's where I first touched both UNIX and a Macintosh, trust me, it's best
> forgotten. Once that WIS Workstation was loaded with MacOS 7, it flew!
> Before that it was a dog, despite being based around a Mac IIfx.
I used to run A/UX on a II (later IIfx) and I liked it. I
didn't find it all that much slower than running the MacOS
straight. I can even remember playing Hellcats (I think
that was the name; it was a WWII flight simulator) under
A/UX and it was pretty smooth.
--
Eric Dittman
dittman(a)dittman.net
"David Williams" <dlw(a)trailingedge.com> wrote:
> that he has a ton of HP2000 manuals and a friend who has HP2000
> hardware he may be interested in parting with. I've wanted to work
> with some HP2000 stuff again since I left high school. All in all a
> good day. :-)
You want to inquire about software too. The hardware is mostly
HP2100-family stuff. The software is what makes it a time-shared
BASIC system, and turning that up would be a Really Good Thing.
-Frank McConnell
This has been a great day. First the Atari Portfolio and the BeBox.
Then I'm picking up a bunch of DEC stuff from Bill here on the list
but the thing that got me really excited is a co-work just told me
that he has a ton of HP2000 manuals and a friend who has HP2000
hardware he may be interested in parting with. I've wanted to work
with some HP2000 stuff again since I left high school. All in all a
good day. :-)
-----
"What is, is what?"
"When the mind is free of any thought or judgement,
then and only then can we know things as they are."
David Williams - Computer Packrat
dlw(a)trailingedge.com
http://www.trailingedge.com
I must say I was a bit surprised at how well done the show was. It wasn't
over-sensationalized at all. On the contrary, I thought it was very well
researched and did a good job of telling the stories and explaining the
technical stuff.
I was glad that they had more quotes from Jonathan Littman than from John
Markoff. Littman told Mitnick's story closer to what really was going on,
while Markoff stuck to his agenda of vilifying Mitnick, which he's spent
the better part of the last five years of his career doing. Markoff is
the kind of reporter I despise; one who attempts to make the news or mold
it in his view rather than simply report it.
But I don't think Mitnick's story is as rosy as he paints it either, and I
think he's spinning some revisionism on it. He's certainly got some
skeletons in his past that he's not owning up to.
Anyhoo, Draper's story is pretty much how I've heard it told before. He
really was just an unfortunate fall guy of sorts.
The warehouse where they filmed Draper is where my computers used to be
stored (well, a few still are, I'm not quite done moving yet :) There
were some shots of me typing on an Apple ][ (you may have noticed the
"CALL -151" on the screen at one point :) but you couldn't tell who it
was, just hands. The display of 1's and 0's that showed periodically was
generated on an Apple ][ as well (that is, by far, the acme of my career).
There was also some other stuff, like 6502 assembler scrolling by, and of
course the computers they showed rotating were all mine ;)
Well, that was fun. One to the next show: I'm providing some Altair
footage for a National Geographic special on computer history.
I'm also in the process of developing a documentary on the F14 flight
control computer, but that's a slow-going affair. Once the VCF's are over
for the year then I hope to kick that up into full gear.
Sellam Ismail Vintage Computer Festival
------------------------------------------------------------------------------
International Man of Intrigue and Danger http://www.vintage.org
On July 27, Bill Bradford wrote:
> Check out http://content.sunhelp.org/boards/
>
> Anybody know what these might be out of?
Definitely not DEC boards. Vaguely NCR-ish, but I'm really not
sure. Can you put up a closeup of the backplane-side card-edge
connectors?
-Dave McGuire
