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<p>I can't remember now, but I believe the KA was de-supported from
Tops-10 in the 6.00 series monitor at some point.</p>
<p>What I recall was that WPI had a version of Tops-10 that was
later than 6.03B to where the KA support had been dropped. They
managed to put the KA back in and this is what we ran. I <i>think</i>
this may have been 6.05. WPI also had an odd feature of a 'third'
segment, but I couldn't imagine what that means nor how they did
that; I was really starting to focus on Tops-20 at the time.</p>
<p>I don't remember when SMP showed up, but I'm pretty sure it would
have been in some 600 series monitor.<br>
</p>
<div class="moz-cite-prefix">
<p>I had been wondering what the user section count was for the
SC30/40. The KL can do 5 bits (32 of them), which gets you 8 MW
virtual, which is twice the maximum physical memory. The TOAD
can do 12 bits (4096), which gets you 1 GW. I recall that the
SC was "in between", but I can't remember that particular
virtual limit.</p>
</div>
<div class="moz-cite-prefix">I had thought that the TOAD (or some
version) could do more than 32 KW physical.<br data-mce-bogus="1">
</div>
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cite="mid:244554644.131045.1634684852551.JavaMail.zimbra@stupi.com">
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<hr width="100%" size="2">On 10/19/21 7:07 PM, Peter
Lothberg wrote:<br>
<br>
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Fotnode, MRC gave me the BBN pager from Sails KA, and I later
gave it to LCM, together with 3 KA's and the BBN pager and
the boards for the KA to connect to the pager. In the late
80's we also did build a ITS-pager for the KA.<br
data-mce-bogus="1">
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<div><br data-mce-bogus="1">
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<div>One of the KA's we brought up 6.03A on in 2019. Ralph Gorin
pushed the "read-in" button for that event.<br
data-mce-bogus="1">
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<div><br data-mce-bogus="1">
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<div>The SC30/SC40 can do "KI-Style" Tops10 10 pager and
"KL-Style" Tops 20 paging. The Toad is 'special' it has a lot
of the KC10 fetures and don't do any "KI style" things and has
32MW of memory.<br data-mce-bogus="1">
</div>
<div><br data-mce-bogus="1">
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<div>-P<br data-mce-bogus="1">
</div>
<div><br>
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<hr id="zwchr" data-marker="__DIVIDER__">
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<blockquote style="border-left:2px solid
#1010FF;margin-left:5px;padding-left:5px;color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;"><b>From:
</b>"tommytimesharing" <a class="moz-txt-link-rfc2396E" href="mailto:tommytimesharing@gmail.com"><tommytimesharing@gmail.com></a><br>
<b>To: </b>"hecnet" <a class="moz-txt-link-rfc2396E" href="mailto:hecnet@Update.UU.SE"><hecnet@Update.UU.SE></a><br>
<b>Sent: </b>Tuesday, October 19, 2021 6:53:31 PM<br>
<b>Subject: </b>Re: [HECnet] A2RTR downtime<br>
</blockquote>
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<blockquote style="border-left:2px solid
#1010FF;margin-left:5px;padding-left:5px;color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;">
<p>I understand your point here and you are--of
course--correct, yet one hesitates to term Tops-20 (TWENEX
) paging as being a variant of the BBN pager (or better
TENEX).<br>
</p>
<div class="moz-cite-prefix">The BBN pager was <i>far</i>
more capable then the both the KI and KL pagers. The KL
pager was more capable than the KI, but this didn't put it
quite in the same league as the BBN pager in terms of
functionality.</div>
<div class="moz-cite-prefix">
<p>This is most visible in what <font size="4"
face="monospace">RPACS%</font> (Read PAge ACess)
returns (or fails to return) and what <font size="4"><tt>SPACS%</tt></font>
(Set PAge ACess) does (or fails to do). On the KL, the
only access bit you can set is whether the page is
writable (this includes Copy-On-Write). You cannot:</p>
<ol>
<li>Clear all bits and thus set a page 'No Access'; it
will still be there</li>
<li>Set a page Write-only</li>
<li>Set a page Execute-Only<br>
</li>
</ol>
<p>Case 1. is necessary for implementing guard pages which
are (IMHO) one of the very most effective hardware based
debugging tools around. You really want "Explode on
Reference" to catch stray reads AND stores. If you
whack the page, then all that happens the next time you
touch it is it 're-materializes'.</p>
<p>Case 2 is great for increasing the security of certain
communications paradigms.</p>
<p>For 1., you can solve it in two convoluted ways. First,
you can hook the page creation interrupt and determine
whether you are creating something you ought not. You
can also actually implement "Explode on Reference" by
mapping 1+ the last page of a locked file. If you then
try to touch that page, it will fail because creating
the page in memory involves creating it in the (locked)
backing store. I discovered this by mistake when
looking for a guard page implementation for my FTP
server.</p>
<p>2. Has no real solution, but paged mode IPCF% is
probably good enough.</p>
<p>3. is partly solved by setting the file execute only,
but this is highly restricted and does not work if a
program is multi-process (I.E., forks). Thus, I can not
use it in the FTP server nor can it be used in the
Tops-20 TELNET client.<br>
</p>
<p>BBN repeatedly tried to get DEC to take their pager,
but DEC never went for it. I don't remember what was
designed for the Jupiter or was implemented for the
SC-40 or TOAD. </p>
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<pre class="moz-quote-pre">On 10/18/21 10:03 PM, Robert Armstrong wrote:
<blockquote><pre class="moz-quote-pre"><pre class="moz-quote-pre">T10 in the last incarnation(s) could use the KL10 paging
</pre></pre></blockquote>
Umm.. TOPS-10 could always use the "KL10 paging". TOPS10 ran on the KL from day 1.
The thing is, the KL had different microcode for TOPS-10 paging and TOPS-20 paging. The hardware didn't change. TOPS-10 paging was the same as the KL10 paging, which was implemented in hardware. TOPS-20 paging (or rather, TWENEX paging) was some variant of the BBN pager that was originally attached to a KA10 way back when.
Bob
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