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<p>Sir, I stand <b>corrected</b> and do humbly admit my errors. I
didn't see anything Orange on the mac.io website, so I just
assumed... I didn't go to the Facebook site because I won't have
a thing to do with their policies, stated or covert.</p>
<p>A memory surfaced and I realized that I was also completely wrong
about the 2020's networking capabilities, too. In 1979, DEC's
Federal Systems group had a 2020 on the ARPAnet and I used it to
send email to some of my pals at MIT LCS when I working 2nd and
3rd shift. So the hardware existed to communicate with an IMP and
MIT used it implement TCP/IP on ITS. This is simulated by the
KLH10 2020 implementation and that's how ITS communicates today.</p>
<p>Federal Systems was a real hike from manufacturing in Marlboro
where I used to hang out; three buildings away. It was also
notable for having mil-spec VT100's. Instead of plastic, they
were made out of very thick metal, I think maybe machined
aluminum. The cables where sheathed in metal and the connectors
were substantially enlarged and strengthened. The display glass
also had a dense metal screen in front of it. They really looked
like they could withstand a hand grenade and weighed a ton...
Well that's what I thought at the time, another alternative that
didn't occur to me until decades later was that all this just
could have been RF shielding.<br>
</p>
<p>I had left DEC and was at Columbia before the Internet role out,
so I don't know whether Tops-20 4.1, the last official release for
the 2020, supported TCP/IP. I just can't remember, darn it... I
know that Tops-20 5.0 supported TCP/IP AND that MRC was able to
port 5.0 to the 2020. LingLing was on the Internet from time to
time. That must have been some hack; by late version 3, it was
seen that the monitor was running out of address space and when
the hardware folks suggested eliminating the symbol table, the
monitor folks flipped as debugging would have been effectively
hatcheted.<br>
</p>
<div class="moz-cite-prefix">The solution for 4.1 was one of the
finest hacks I have ever heard of; while the 2020 doesn't support
extended addressing, it does support multiple address spaces, so
what they did was move all the symbols into a separate address
space. This was called 'hiding' symbols and I thought it was
great because it made them harder to smash. However, all of that
went out the window with 5.0, which fully supported extended
addressing.</div>
<div class="moz-cite-prefix">
<p>DEC completely walked away from the 2020 and symbol hiding for
the Tops-20 5.0 monitor. In fact, I remember an SPR response
scolding an acquaintance of mine for trying to turn symbol
hiding back on in 5.0. Basically, it was a corporate,
'Fuggetaboutit'. Pity; for user programs, Tenex and Tops-20 had
something called IDDT (Invisible DDT) which kept the symbols in
a completely different process space, effectively making them
impossible to smash, no matter how sick your program got.
Symbol hiding was cool. Not that I'm going to try figure out
how to turn it back on...</p>
<p>You know, I have been out to Pittsburgh a few times. In the
1980's, Columbia flew me out there so that I could learn about
CMU's modifications to LPTSPL to support the nearly entirely
awesome Xerox 9700. I was out there again about a year ago for
a conference. Still, that's a real hike... My relatives live
in near Elizabethtown, not quite spitting distance from three
mile island (!!), so that's another four hours to New Kensington
after they're done with me. Ouch... Oh well, never say
'never'...<br>
</p>
</div>
<div class="moz-cite-prefix">That's some pretty good swag you have
by the way; minor suggestion, in addition to the anti-VAXer
T-shirt, you might want to have another one that says the somewhat
subtle, "If it doesn't have 36 Bits, it isn't a Digital
computer". I did know some people who were so anti-VAX that they
positively would froth at the mouth. I could understand the
frothing, given what happened, but still, one prefers not wear
one's froth on their sleeve. It would have been a lot better for
everybody had there been more and better communication and less
NIH.<br>
</div>
<blockquote type="cite"
cite="mid:1a1d2fd0-b795-2cbd-75e6-b0db550f2c6d@neurotica.com">
<hr width="100%" size="2">
<pre class="moz-quote-pre" wrap="">On 4/23/20 12:20 AM, Dave McGuire wrote:
</pre>
<blockquote type="cite">
<hr width="100%" size="2">
<pre class="moz-quote-pre" wrap="">On 4/22/20 11:42 PM, Thomas DeBellis wrote:
Oh, I'm in Looooong Island, South Shore.
</pre>
</blockquote>
<pre class="moz-quote-pre" wrap="">
Ahhh, New Yawwwk. You should head out this way at some point.
</pre>
<blockquote type="cite">
<pre class="moz-quote-pre" wrap="">I actually have relatives not far from you in PA, but I hadn't gotten
around to noodging you yet for the distinct lack of 20's in your
collection. I mean, you have a 4341 yet no 20? Tisk, tisk...
</pre>
</blockquote>
<pre class="moz-quote-pre" wrap="">
You sir are misinformed. There are three KS10s here.
</pre>
<blockquote type="cite">
<pre class="moz-quote-pre" wrap="">Well, I'm pulling your leg a bit; a 20 is a seriously heavy lift. A KL
has three purposes in life: 1) Generate Heat, 2) Suck Power, 3) Run
winning code. A 2020 uses far less power, but doesn't have extended
addressing, so it is stuck at Tops-20 4.1, which leaves out a lot of
DECnet (and ARPAnet) stuff. Apparently, you can squeeze 5.0 in; MRC did
this, but that was MRC. Tops-20 is at version 7.0 now.
</pre>
</blockquote>
<pre class="moz-quote-pre" wrap="">
Indeed.
</pre>
<blockquote type="cite">
<pre class="moz-quote-pre" wrap="">And both of them are seriously cranky beasts that needed care and
feeding from trained service personnel; wire wrap and all that (yech).
Remember, it's not a mainframe unless you can't fit it in your house and
have to take out a second mortgage to pay for the electricity and tons
(60 for a 20) of air conditioning.
</pre>
</blockquote>
<pre class="moz-quote-pre" wrap="">
We're no strangers to cranky around here. ;)
</pre>
<blockquote type="cite">
<pre class="moz-quote-pre" wrap="">So Paul Allen had a KL based 20, which is now in the the Living Computer
museum. But that cost was apparently less than a rounding error
compared to what he was worth. A mere monetary blip, as it were.
</pre>
</blockquote>
<pre class="moz-quote-pre" wrap="">
Yep.
-Dave
</pre>
</blockquote>
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